JP2008155357A - Structural body and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for easily manufacturing a fine structural body including a metal layer and the structural body manufactured by the manufacturing method. <P>SOLUTION: This structural body is formed on a substrate 1 by performing at least a process for forming a coating film 21 including the metal layer formed by electroless plating on a surface of a template 11 provided on the substrate 1 and a process for removing a part or all of the template 11 in a state of leaving a part or all of the coating film 21. Alternatively, the structural body is formed on the substrate 1 by performing at least a process for forming the coating film 21 including the metal layer formed by electroless plating on the surface of the template 11 provided on the substrate 1 and a process for removing a part of the coating film 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a structure including at least a metal layer, and a structure manufactured by the manufacturing method.

In recent years, a technique for manufacturing a fine structure has been actively researched and developed because it is expected to be applied to various fields. For example, structures with nanometer-sized structures (nanomaterials), which have different physical and chemical properties from the corresponding bulk materials, are attracting considerable attention from both basic and applied research aspects. . For example, a nanomaterial having a hollow three-dimensional structure such as a cylinder is expected to be useful in various fields including inclusion chemistry, electrochemistry, materials, biomedicine, sensors, catalysts, separation techniques, and the like. In addition, since the technology for producing a line-shaped fine pattern is directly related to the production and high integration of an integrated circuit, research and development is being actively conducted in the semiconductor field and the like.
As a conventional method for manufacturing a fine structure, a technique called a mold method, a method using a lithography method, and the like are known. For example, Non-Patent Document 1 discloses a nanomaterial having a spherical capsule-type hollow three-dimensional structure by dispersing template fine particles in a solution, coating the surface of the template fine particles with a thin film, and then removing the template fine particles. A manufacturing method has been proposed.
Further, the present applicants coated the nanopattern-formed template surface with a metal oxide film or a composite film of a metal oxide and an organic compound, and finally removed the template to form a nanostructure. The method of manufacturing a body is proposed (refer to patent documents 1 and 2).

As a method for producing a metal microstructure, (1) a method of forming a fine pattern on a metal layer by a lithography method, and etching the metal layer using the fine pattern as a mask, and (2) a method of forming by a lithography method. A method of performing metal plating on a fine pattern is known.
Advanced Materials, 13 (1), 11-22 (2001) JP 2005-205584 A JP 2006-297575 A

However, in the conventional method, a structure having at least a part of a nanometer-sized structure (nanostructure), for example, a metal layer having a thickness of about nanometers to several tens of nanometers is created. It ’s difficult. For example, in the above method (1), it is very difficult to form a nano-sized fine pattern itself. Even if it can be formed, the etching resistance of the fine pattern is low, and etching with a metal substrate is difficult. The selectivity becomes a problem, and it is difficult to obtain a fine structure. In the method (2), as in the case (1), it is very difficult to form a fine pattern, and it is also difficult to perform plating on such a fine pattern. In particular, a structure having a large aspect ratio (ratio of height to width), such as a line-like or columnar structure, is held in a self-supporting manner on the substrate, that is, from the substrate without support. It is extremely difficult to form an upright state.
This invention is made | formed in view of the said situation, Comprising: It aims at providing the manufacturing method which can manufacture the fine structure containing a metal layer easily, and the structure manufactured by this manufacturing method.

In order to achieve the above object, the present invention employs the following configuration.
That is, the first aspect of the present invention includes a step of forming a coating film including a metal layer formed by electroless plating on at least the surface of a mold provided on a substrate; A structure manufacturing method is characterized in that a structure is formed on the substrate by performing a step of removing a part or all of the template while leaving a part or all of the template.
The second aspect of the present invention includes a step of forming a coating film including a metal layer formed by electroless plating on at least a surface of a mold provided on a substrate, and a part of the coating film The structure is formed on the base material by performing the step of removing the structure.
A third aspect of the present invention is a structure manufactured by the structure manufacturing method of the first aspect or the second aspect.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method which can manufacture the fine structure containing a metal layer easily, and the structure manufactured by this manufacturing method can be provided.

≪Structure manufacturing method≫
The structure production method of the first aspect of the present invention (hereinafter sometimes referred to as the production method (1) of the present invention) is carried out by electroless plating on at least the surface of the mold provided on the substrate. A step of forming a coating film including a metal layer to be formed (hereinafter referred to as a coating film forming step), and removing a part or all of the mold while leaving a part or all of the coating film. The structure is formed on the base material by performing the step of performing (mold removing step).

Hereafter, each process and the material used there are demonstrated in detail.
<Base material, mold>
In the production method (1) of the present invention, first, a base material provided with a mold is prepared.
The type of substrate is not particularly limited as long as a mold can be formed thereon. For example, from a metal such as silicon, copper, chromium, iron, and aluminum, an inorganic material such as glass, titanium oxide, silica, and mica. Typically, a base material made of an organic compound such as an acrylic plate, polystyrene, cellulose, cellulose acetate, or phenol resin is used. The base material may be provided with an organic or inorganic antireflection film on the surface thereof.
In particular, when performing electroless plating, it is difficult to form a metal layer on the surface of the substrate, and a metal layer is selectively formed on the mold surface (excellent plating selectivity), so that the silicon substrate, graphite, Teflon (Registered trademark), acrylic plate, polystyrene, phenol resin, and the like are suitable as the base material.
The size, shape, etc. of the substrate are not particularly limited. The base material does not necessarily have a smooth surface, and base materials of various materials and shapes can be appropriately selected. For example, a substrate having a curved surface, a flat plate having a concavo-convex shape, and various shapes such as a flake shape can be used.

The mold is not particularly defined unless it deviates from the gist of the present invention. For example, a mold produced by lithography, a mold produced by contact printing, a mold produced by imprinting, a mold produced by mechanical microfabrication, LIGA (lithography, electroplating and mold molding (Lithographie Galvanformung und Abforming), a beam drawing mold, etc. Among these, a mold prepared by a lithography method is preferable.
Moreover, as a casting_mold | template, you may employ | adopt the casting_mold | template which carries out a physical process and / or a chemical process to the surface of the above casting_mold | templates. Examples of the physical treatment and / or chemical treatment include polishing, adhesion operation such as forming a thin film on the surface, plasma treatment, solvent treatment, chemical decomposition of the surface, heat treatment, stretching treatment, and the like.

The shape and size of the mold may be appropriately set according to the shape and size of the structure to be obtained, and is not particularly limited.
Specific examples of the shape of the mold include, for example, rectangular shapes, cylinders, holes, lines and their network structures and branch structures, polygons and their composite / repetitive structures, circuit structures such as those found in integrated circuits, and lattice shapes. Can be adopted.
For example, when trying to obtain a line-shaped structure, it is preferable to form a line pattern having a rectangular cross section as a mold. In this case, as will be described later, a coating film is formed on the surface of the mold, and after removing the upper end of the coating film, the mold is removed, so that only the side wall portion of the coating film remains on the substrate. . As a result, a structure having a line shape (a line in which the width is the thickness of the coating film and the height is the height of the remaining side wall portion) is formed on the base material.
For example, when obtaining a cylinder (cylinder) -like structure, it is preferable to form a hole pattern or a columnar pattern as a mold. In this case, as will be described later, a coating film is formed on the surface of the mold, and after removing the upper end of the coating film, the mold is removed, so that only the side wall portion of the coating film remains on the substrate. . As a result, a cylinder-shaped structure having the same outer diameter as the inner diameter of the hole is obtained.

  The material for forming the mold (mold forming material) is not particularly limited, and a material suitable for the pattern forming method may be appropriately selected. Hereinafter, the mold forming material preferably used in the present invention will be described.

[Mold forming material]
In the present invention, as a material for forming a template (template forming material), a template forming material containing an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, a template excellent in strength, shape and the like can be formed. Moreover, it is easy to form a nano-sized template. In addition, there is an advantage that a mold formed using such a mold forming material can be easily removed by etching with hydrogen gas or the like.
As said organic compound, what is generally used as a base-material component of the film forming material can be utilized. Here, the “base material component” is an organic compound having a film forming ability.
The organic compounds are roughly classified into low molecular weight organic compounds having a molecular weight of 500 or more and 2,000 or less (hereinafter referred to as low molecular compounds) and high molecular weight compounds having a molecular weight of more than 2000. As the low molecular weight compound, a non-polymer is usually used. As the polymer compound, a resin (polymer, copolymer) is usually used, and in that case, a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used as the “molecular weight”. . Hereinafter, when the term “resin” is simply used, the molecular weight is 2000 or more.

Especially as said organic compound, since it is easy to form a metal layer on the casting_mold | template surface, what has a hydrophilic group is preferable.
As the hydrophilic group, at least one selected from the group consisting of a hydroxyl group, a carboxy group, a carbonyl group, an ester group, an amino group, and an amide group is preferably used. Of these, hydroxyl groups (particularly alcoholic hydroxyl groups or phenolic hydroxyl groups), carboxy groups, and ester groups are more preferred. Among these, at least one selected from the group consisting of a carboxy group, an alcoholic hydroxyl group, and a phenolic hydroxyl group is preferable.
When the organic compound is a polymer compound, the hydrophilic group is preferably 0.2 equivalents or more, and more preferably 0.5 to 0.8 equivalents. In the case where the polymer compound is composed of a structural unit having a hydrophilic group and other structural units, the former structural unit is 20 mol% or more, more preferably 50 to 80 mol%. Means.
When the organic compound is a low molecular compound, the hydrophilic group preferably has 1 to 20 equivalents, more preferably 2 to 10 equivalents, per molecule of the low molecular compound. Here, for example, “having 1 to 20 equivalents of hydrophilic group per molecule” means that 1 to 20 hydrophilic groups are present in one molecule.

As a template forming method, as described above, the lithography method is preferably used.
In the lithography method, a resist composition that is a material having radiation sensitivity is used. The resist composition is not particularly limited, and any resist composition proposed so far may be appropriately selected and used. Resist compositions include a positive type in which alkali solubility increases upon exposure and a negative type in which alkali solubility decreases upon exposure. In the present invention, a positive resist composition is particularly preferable.

As a resist composition, since it is excellent in sensitivity, resolution, etc., a base component (A) (hereinafter referred to as (A) component) whose alkali solubility is changed by the action of an acid, and an acid is generated upon exposure. A chemically amplified resist composition containing an acid generator component (B) (hereinafter referred to as component (B)) is preferred.
There is no restriction | limiting in particular as a chemically amplified resist composition, It can select suitably from many chemically amplified resist compositions proposed until now and can use it. The chemically amplified resist composition includes a base component (A ′) whose alkali solubility is changed by the action of an acid (hereinafter referred to as “component (A ′)”) and an acid generator that generates an acid upon irradiation with radiation. What contains a component (B ') (henceforth (B') component) is common.

When the chemically amplified resist composition is a negative resist composition, as the component (A ′), a base material component whose alkali solubility is reduced by the action of an acid is used. Furthermore, a crosslinking agent is blended.
In such a negative resist composition, when an acid is generated from the component (B ′) by exposure, crosslinking occurs between the component (A ′) and the crosslinking agent by the action of the acid, and the component (A ′) is an alkali. Changes from soluble to insoluble in alkali. Therefore, when an organic film (resist film) obtained by applying the negative resist composition on a substrate is selectively exposed, the exposed portion turns to alkali-insoluble while the unexposed portion is alkali-soluble. Therefore, only the unexposed portion is removed by alkali development, and a resist pattern (template) is formed.
As the component (A ′) of the negative resist composition, an alkali-soluble resin is usually used. As the alkali-soluble resin, α- (hydroxyalkyl) acrylic acid, or lower of α- (hydroxyalkyl) acrylic acid is used. A resin having a unit derived from at least one selected from alkyl esters is preferable because it can form a good resist pattern with little swelling. Note that α- (hydroxyalkyl) acrylic acid includes acrylic acid in which a hydrogen atom is bonded to the α-position carbon atom to which the carboxy group is bonded, and a hydroxyalkyl group (preferably having 1 carbon atom) in the α-position carbon atom. One or both of [alpha] -hydroxyalkylacrylic acids to which (5) hydroxyalkyl groups) are attached.
As the crosslinking agent, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

When the chemically amplified resist composition is a positive resist composition, as the component (A ′), a base material component having an acid dissociable, dissolution inhibiting group and increasing alkali solubility by the action of an acid is used. .
Such a positive resist composition is insoluble in alkali before exposure. When an acid is generated from the component (B ′) by exposure, the acid dissociable, dissolution inhibiting group is dissociated by the action of the acid, and the component (A ′) Changes to alkali-soluble. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the positive resist composition on the base material is selectively exposed, the exposed portion turns into alkali-soluble, while the unexposed portion becomes alkaline. Since it remains insoluble and does not change, only the exposed portion is removed by alkali development, and a resist pattern is formed.
The acid dissociable, dissolution inhibiting group has an alkali dissolution inhibiting property that makes the entire component (A ′) before exposure insoluble in alkali, and simultaneously dissociates by the action of an acid generated from the component (B ′) after exposure, and (A ') A group that changes the entire component to alkali-soluble. The acid dissociable, dissolution inhibiting group is not particularly limited, and may be any one used in a chemically amplified positive resist composition.

As the (A ′) component of the positive resist composition, the following (A′-1) component and / or (A′-2) component is more preferable. The hydrophilic group may also serve as an acid dissociable, dissolution inhibiting group.
-(A'-1) component: Resin which has an acid dissociable, dissolution inhibiting group.
-(A'-2) component: a low molecular compound having an acid dissociable, dissolution inhibiting group.
Hereinafter, preferred embodiments of the component (A′-1) and the component (A′-2) will be described more specifically.

[(A′-1) component]
Examples of the component (A′-1) include a resin having a structural unit having an acid dissociable dissolution inhibiting group, and in particular, a structural unit having an acid dissociable dissolution inhibiting group and a structural unit having a hydrophilic group. Resins are preferred.
The proportion of the structural unit having the acid dissociable, dissolution inhibiting group in the resin is preferably 20 to 80 mol% with respect to the total amount of all structural units constituting the resin. Is more preferable, and 30 to 60 mol% is more preferable.
The proportion of the structural unit having the hydrophilic group in the resin is preferably 20 to 80 mol%, more preferably 20 to 70 mol%, based on the total amount of all the structural units constituting the resin. 20 to 60 mol% is more preferable.
Preferably, the structural unit having a hydrophilic group is a structural unit having a carboxy group, an alcoholic hydroxyl group or a phenolic hydroxyl group, more preferably an acrylic acid, methacrylic acid or an alcoholic hydroxyl group (α-lower alkyl). A unit derived from an acrylate ester and hydroxystyrene.

More specifically, as the component (A′-1), a novolak resin having an acid dissociable, dissolution inhibiting group, a hydroxystyrene resin, an (α-lower alkyl) acrylate resin, and a structural unit derived from hydroxystyrene And a copolymer resin containing a structural unit derived from (α-lower alkyl) acrylic ester is preferably used.
In the present specification, the “hydroxystyrene-based resin” is a resin that includes a structural unit derived from hydroxystyrene or an ester thereof and does not include a structural unit derived from an (α-lower alkyl) acrylate ester. is there. The “(α-lower alkyl) acrylic ester resin” includes a structural unit derived from (α-lower alkyl) acrylic ester and does not include a structural unit derived from hydroxystyrene or an ester thereof. It is.
The “structural unit derived from hydroxystyrene” is a structural unit formed by cleaving an ethylenic double bond of hydroxystyrene or α-lower alkylhydroxystyrene, and may hereinafter be referred to as a hydroxystyrene unit. “Α-lower alkylhydroxystyrene” indicates that the lower alkyl group is bonded to the carbon atom to which the phenyl group is bonded.
“(Α-Lower alkyl) acrylic acid” refers to one or both of acrylic acid (CH ₂ ═CH—COOH) and α-lower alkylacrylic acid.
α-Lower alkyl acrylic acid refers to one in which a hydrogen atom bonded to a carbon atom to which a carbonyl group in acrylic acid is bonded is substituted with a lower alkyl group.
“(Α-Lower alkyl) acrylic acid ester” is an ester derivative of “(α-lower alkyl) acrylic acid” and represents one or both of acrylic acid ester and α-lower alkyl acrylic acid ester.
The “structural unit derived from (α-lower alkyl) acrylic acid ester” is a structural unit formed by cleavage of an ethylenic double bond of (α-lower alkyl) acrylic acid ester. -Lower alkyl) acrylate structural unit. “(Α-lower alkyl) acrylate” refers to one or both of acrylate and α-lower alkyl acrylate.
In the “structural unit derived from α-lower alkylhydroxystyrene” and the “structural unit derived from α-lower alkyl acrylate ester”, the lower alkyl group bonded to the α-position has 1 to 5 carbon atoms. An alkyl group, preferably a linear or branched alkyl group, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group Etc. Industrially, a methyl group is preferable.

  The resin suitable as the component (A′-1) is not particularly limited, and examples thereof include the following components (A′-11) and (A′-12).

"(A'-11) component"
The component (A′-11) is a resin having a structural unit having a phenolic hydroxyl group and a structural unit having an acid dissociable, dissolution inhibiting group, and the resin has an alkali-insoluble structural unit as necessary. May be.
Examples of the structural unit having a phenolic hydroxyl group include the following structural unit (a′1).
Examples of the structural unit having an acid dissociable, dissolution inhibiting group include the following structural unit (a′2) and structural unit (a′3).
Examples of the alkali-insoluble constituent unit include the following constituent (a′4).

..Structural unit (a'1)
The structural unit (a′1) is a structural unit derived from hydroxystyrene, and is preferably a structural unit represented by the following general formula (I ′).

（式中、Ｒは水素原子、炭素数１〜５のアルキル基、ハロゲン原子またはハロゲン化アルキル基を示す。）

(In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom or a halogenated alkyl group.)

Specific examples of the alkyl group for R include lower linear chains such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. Or a branched alkyl group. Examples of the halogen atom for R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the halogenated alkyl group for R include groups in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms have been substituted with the halogen atoms.
R is preferably a hydrogen atom or a lower alkyl group, and most preferably a hydrogen atom or a methyl group in terms of industrial availability.
The description of R is the same below.
The bonding position of —OH to the benzene ring is not particularly limited, but the position 4 (para position) described in the formula is preferred.

The structural unit (a′1) can be used alone or in combination of two or more.
In the component (A′-11), the proportion of the structural unit (a′1) is preferably 40 to 80 mol% with respect to the total amount of all structural units constituting the component (A′-11). More preferably, it is 50-75 mol%. By setting it as 40 mol% or more, the solubility with respect to an alkali developing solution can be improved, and the improvement effect of a pattern shape is also acquired. The balance with other structural units can be taken by setting it as 80 mol% or less.

..Structural unit (a'2)
The structural unit (a′2) is represented by the following general formula (II ′).

（式中、Ｒは上記と同じであり、Ｘは酸解離性溶解抑制基を示す。）

(In the formula, R is the same as above, and X represents an acid dissociable, dissolution inhibiting group.)

X is, for example, an alkyl group having a tertiary carbon atom, wherein the tertiary carbon atom of the tertiary alkyl group is bonded to the ester group [—C (O) O—]. And a cyclic acetal group such as a tetrahydropyranyl group and a tetrahydrofuranyl group.
As X, those other than the above can be arbitrarily used from the acid dissociable, dissolution inhibiting groups used in the chemically amplified positive resist composition.

  As the structural unit (a′2), for example, those represented by general formula (III ′) shown below are preferred.

In the formula, R is the same as described above, and R ¹¹ , R ¹² , and R ¹³ are each independently an alkyl group (which may be linear or branched. Preferably, it is an alkyl group having 1 to 5 carbon atoms. ). Or, among R ¹¹ , R ¹² and R ¹³ , R ¹¹ may be a lower alkyl group, and R ¹² and R ¹³ may be bonded to form a monocyclic or polycyclic aliphatic cyclic group. . The aliphatic cyclic group preferably has 5 to 12 carbon atoms.

Here, in the present specification and claims, “aliphatic” is a relative concept with respect to aromatics, and means a group, a compound, or the like that does not have aromaticity. The “aliphatic cyclic group” indicates a monocyclic group or polycyclic group having aromaticity.
In the aliphatic cyclic group, the basic ring structure excluding the substituent may be a group consisting of carbon and hydrogen (aliphatic hydrocarbon group), and on the ring skeleton of the aliphatic hydrocarbon group. It may be an aliphatic heterocyclic group in which a carbon atom is substituted with a heteroatom.
The aliphatic hydrocarbon group may be saturated or unsaturated, but is usually preferably saturated. Specific examples of the aliphatic hydrocarbon group include a group in which one or more hydrogen atoms have been removed from a monocycloalkane; one or more hydrogen atoms have been removed from a polycycloalkane such as a bicycloalkane, tricycloalkane, or tetracycloalkane. The group etc. can be illustrated. Specifically, a group obtained by removing one or more hydrogen atoms from a monocycloalkane such as cyclopentane or cyclohexane, or one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom. In these groups, some or all of the hydrogen atoms may be substituted with a substituent (for example, a lower alkyl group, a fluorine atom or a fluorinated alkyl group).

When R ¹¹ , R ¹² and R ¹³ do not have an aliphatic cyclic group, for example, it is preferable that R ¹¹ , R ¹² and R ¹³ are all methyl groups.
In the case where any of R ¹¹ , R ¹² and R ¹³ has an aliphatic cyclic group, when the aliphatic cyclic group is a monocyclic aliphatic cyclic group, as the structural unit (a′2), For example, those having a cyclopentyl group or a cyclohexyl group are preferred.
When the aliphatic cyclic group is a polycyclic alicyclic group, preferred examples of the structural unit (a′2) include those represented by the following general formula (IV ′).

［式中、Ｒは上記と同じであり、Ｒ^１４はアルキル基（直鎖、分岐鎖のいずれでもよい。好ましくは炭素数１〜５のアルキル基である。）］

[Wherein, R is the same as above, and R ¹⁴ is an alkyl group (which may be linear or branched. Preferably, it is an alkyl group having 1 to 5 carbon atoms.]]

  Moreover, what is represented by the following general formula (V ') as a thing which has an acid dissociable, dissolution inhibiting group containing a polycyclic aliphatic cyclic group is also preferable.

［式中、Ｒは上記と同じであり、Ｒ^１５、Ｒ^１６は、それぞれ独立にアルキル基（直鎖、分岐鎖のいずれでもよい。好ましくは炭素数１〜５のアルキル基である。）である。］

[Wherein, R is the same as described above, and R ¹⁵ and R ¹⁶ are each independently an alkyl group (which may be linear or branched, preferably an alkyl group having 1 to 5 carbon atoms). is there. ]

The structural unit (a′2) can be used alone or in combination of two or more.
In the component (A′-11), the proportion of the structural unit (a′2) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, and still more preferably 10 to 35 mol%.

..Structural unit (a'3)
The structural unit (a′3) is represented by the following general formula (VI ′).

（式中、Ｒは上記と同じであり、Ｘ’は酸解離性溶解抑制基を示す。）

(In the formula, R is the same as above, and X ′ represents an acid dissociable, dissolution inhibiting group.)

X ′ is, for example, a tertiary alkyloxycarbonyl group such as a tert-butyloxycarbonyl group or a tert-pentyloxycarbonyl group; a tertiary alkyloxycarbonyl group such as a tert-butyloxycarbonylmethyl group or a tert-butyloxycarbonylethyl group. Tertiary alkyloxycarbonylalkyl group; Tertiary alkyl group such as tert-butyl group and tert-pentyl group; Cyclic acetal group such as tetrahydropyranyl group and tetrahydrofuranyl group; Alkoxyalkyl such as ethoxyethyl group and methoxypropyl group Group and the like. Among these, a tert-butyloxycarbonyl group, a tert-butyloxycarbonylmethyl group, a tert-butyl group, a tetrahydropyranyl group, and an ethoxyethyl group are preferable.
As X ′, those other than the above can be arbitrarily used from the acid dissociable, dissolution inhibiting groups used in the chemically amplified positive resist composition.
In the general formula (VI ′), the bonding position of the group (—OX ′) bonded to the benzene ring is not particularly limited, but the position 4 (para position) shown in the formula is preferable.

The structural unit (a′3) can be used alone or in combination of two or more.
In the component (A′-11), the proportion of the structural unit (a′3) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, and still more preferably 10 to 35 mol%.

..Structural unit (a'4)
The structural unit (a′4) is represented by the following general formula (VII ′).

（式中、Ｒは上記と同じであり、Ｒ^４’は低級アルキル基を示し、ｎ’は０または１〜３の整数を示す。）

(In the formula, R is the same as above, R ^{4 ′} represents a lower alkyl group, and n ′ represents 0 or an integer of 1 to 3).

The lower alkyl group for R ^{4 ′} may be either a straight chain or a branched chain, and preferably has 1 to 5 carbon atoms.
n ′ represents 0 or an integer of 1 to 3, and is preferably 0.

The structural unit (a′4) can be used alone or in combination of two or more.
In the component (A′-11), the proportion of the structural unit (a′4) is preferably 1 to 40 mol%, and more preferably 5 to 25 mol%. By setting it to 1 mol% or more, the effect of improving the shape (particularly improvement of film loss) is enhanced, and by setting it to 40 mol% or less, it is possible to balance with other structural units.

In the component (A′-11), the structural unit (a′1) and at least one selected from the group consisting of the structural unit (a′2) and the structural unit (a′3) are essential, and optionally (A′4) may be included. In addition, a copolymer having all these structural units may be used, or a polymer or a mixture with any one or more of these structural units may be used. Or these may be combined.
Further, the component (A′-11) can optionally contain components other than the structural units (a′1), (a′2), (a′3), and (a′4). It is preferable that the proportion of the structural unit is 80 mol% or more, preferably 90 mol% or more (100 mol% is most preferred).

As the component (A′-11), in particular, “any one of the copolymers having the structural units (a′1) and (a′3), or a mixture of two or more of the copolymers” Or “any one of the copolymers having the structural units (a′1), (a′2) and (a′4), or a mixture of two or more of the copolymers”, respectively. A mixed or mixed mode is most preferable because an effect can be easily obtained. Moreover, it is preferable also from the point of heat resistance improvement.
In particular, a mixture of polyhydroxystyrene protected with a tertiary alkyloxycarbonyl group and polyhydroxystyrene protected with a 1-alkoxyalkyl group is preferred. When such mixing is performed, the mixing ratio (mass ratio) of each polymer (polyhydroxystyrene protected with a tertiary alkyloxycarbonyl group / 1-polyhydroxystyrene protected with 1-alkoxyalkyl group) is, for example, 1/9 to The ratio is 9/1, preferably 2/8 to 8/2, and more preferably 2/8 to 5/5.

"(A'-12) component"
The component (A′-12) is an (α-lower alkyl) acrylate resin having an acid dissociable, dissolution inhibiting group, and is derived from, for example, an (α-lower alkyl) acrylate ester containing an acid dissociable, dissolution inhibiting group. And a resin having the structural unit (a′5).
In the component (A′-12), when the acid dissociable, dissolution inhibiting group is dissociated by the acid generated from the component (B ′), a carboxy group is generated, and the alkali solubility is increased. Further, the presence of the generated carboxy group facilitates the formation of a metal layer on the resist pattern.

..Structural unit (a'5)
As the acid dissociable, dissolution inhibiting group, for example, a resin for resist compositions of ArF excimer laser can be appropriately selected and used from among many proposed ones. In general, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group of (α-lower alkyl) acrylic acid, or a cyclic or chain alkoxyalkyl group is widely known.
Here, the “group that forms a tertiary alkyl ester” is a group that forms an ester by substituting the hydrogen atom of the carboxy group of acrylic acid. That is, it shows a structure in which the tertiary carbon atom of a chain-like or cyclic tertiary alkyl group is bonded to the oxygen atom at the terminal of the carbonyloxy group [—C (O) —O—] of the acrylate ester. In this tertiary alkyl ester, when an acid acts, a bond is cut between an oxygen atom and a tertiary carbon atom.
The tertiary alkyl group is an alkyl group having a tertiary carbon atom.
Examples of the group that forms a chain-like tertiary alkyl ester include a tert-butyl group and a tert-pentyl group.
Examples of the group that forms a cyclic tertiary alkyl ester include those exemplified in the “acid dissociable, dissolution inhibiting group containing an alicyclic group” described later.

The “cyclic or chain alkoxyalkyl group” forms an ester by substituting a hydrogen atom of a carboxy group. That is, a structure is formed in which the alkoxyalkyl group is bonded to the terminal oxygen atom of the carbonyloxy group [—C (O) —O—] of the acrylate ester. In such a structure, the bond between the oxygen atom and the alkoxyalkyl group is broken by the action of the acid.
Examples of such cyclic or chain alkoxyalkyl groups include 1-methoxymethyl group, 1-ethoxyethyl group, 1-isopropoxyethyl, 1-cyclohexyloxyethyl group, 2-adamantoxymethyl group, 1-methyladamant Examples thereof include a xymethyl group, a 4-oxo-2-adamantoxymethyl group, a 1-adamantoxyethyl group, and a 2-adamantoxyethyl group.

As the structural unit (a′5), a structural unit containing an acid dissociable, dissolution inhibiting group containing a cyclic group, particularly an aliphatic cyclic group, is preferable.
Here, “aliphatic” and “aliphatic cyclic group” are as defined above.
The aliphatic cyclic group may be monocyclic or polycyclic, and can be appropriately selected and used from among many proposed, for example, ArF resists. From the viewpoint of etching resistance, a polycyclic alicyclic group is preferred. The alicyclic group is preferably a hydrocarbon group, and particularly preferably a saturated hydrocarbon group (alicyclic group).
Examples of the monocyclic alicyclic group include groups in which one hydrogen atom has been removed from a cycloalkane. Examples of the polycyclic alicyclic group include groups in which one hydrogen atom has been removed from bicycloalkane, tricycloalkane, tetracycloalkane and the like.
Specifically, examples of the monocyclic alicyclic group include a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic group include groups in which one hydrogen atom has been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Among these, an adamantyl group obtained by removing one hydrogen atom from adamantane, a norbornyl group obtained by removing one hydrogen atom from norbornane, a tricyclodecanyl group obtained by removing one hydrogen atom from tricyclodecane, and tetracyclo A tetracyclododecanyl group obtained by removing one hydrogen atom from dodecane is preferred industrially.

More specifically, the structural unit (a′5) is preferably at least one selected from the following general formulas (I ″) to (III ″).
In addition, a unit derived from an (α-lower alkyl) acrylic acid ester having a cyclic alkoxyalkyl group as described above, specifically a 2-adamantoxymethyl group, 1-methyladamant Aliphatic polycyclic alkyloxy lower alkyl (α which may have a substituent such as xymethyl group, 4-oxo-2-adamantoxymethyl group, 1-adamantoxyethyl group, 2-adamantoxyethyl group, etc. -Lower alkyl) It is preferably at least one selected from units derived from acrylic acid esters.

［式（Ｉ”）中、Ｒは上記と同じであり、Ｒ^１は低級アルキル基である。］

[In the formula (I ″), R is the same as above, and R ¹ is a lower alkyl group.]

［式（ＩＩ”）中、Ｒは上記と同じであり、Ｒ^２及びＲ^３はそれぞれ独立に低級アルキル基である。］

[In the formula (II ″), R is the same as defined above, and R ² and R ³ are each independently a lower alkyl group.]

［式（ＩＩＩ”）中、Ｒは上記と同じであり、Ｒ^４は第３級アルキル基である。］

[In the formula (III ″), R is the same as above, and R ⁴ is a tertiary alkyl group.]

In formulas (I ″) to (III ″), the hydrogen atom or lower alkyl group for R is the same as described above for R.
The lower alkyl group for R ¹ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, and an isobutyl group. , A pentyl group, an isopentyl group, a neopentyl group, and the like. Among these, a methyl group and an ethyl group are preferable because they are easily available industrially.
The lower alkyl group for R ² and R ³ is preferably each independently a linear or branched alkyl group having 1 to 5 carbon atoms. Of these, the case where R ² and R ³ are both methyl groups is industrially preferred. Specific examples include structural units derived from 2- (1-adamantyl) -2-propyl acrylate.

R ⁴ is a chain-like tertiary alkyl group or a cyclic tertiary alkyl group. Examples of the chain-like tertiary alkyl group include a tert-butyl group and a tert-pentyl group, and the tert-butyl group is industrially preferable.
The cyclic tertiary alkyl group is the same as that exemplified in the aforementioned “acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group”, and includes a 2-methyl-2-adamantyl group, 2-ethyl- A 2-adamantyl group, 2- (1-adamantyl) -2-propyl group, 1-ethylcyclohexyl group, 1-ethylcyclopentyl group, 1-methylcyclohexyl group, 1-methylcyclopentyl group and the like can be mentioned.
The group —COOR ⁴ may be bonded to the 3 or 4 position of the tetracyclododecanyl group shown in the formula, but the bonding position cannot be specified. Similarly, the carboxy group residue of the acrylate structural unit may be bonded to the position 8 or 9 shown in the formula.

The structural unit (a′5) can be used alone or in combination of two or more.
In the component (A′-12), the proportion of the structural unit (a′5) is preferably 20 to 60 mol% with respect to the total of all the structural units constituting the component (A′-12). 30-50 mol% is more preferable, and 35-45 mol% is the most preferable. A pattern can be obtained by setting it to the lower limit value or more, and balancing with other structural units can be achieved by setting the upper limit value or less.

In addition to the structural unit (a′5), the component (A′-12) preferably further has a structural unit (a′6) derived from an acrylate ester having a lactone ring. The structural unit (a′6) is effective in increasing the adhesion of the resist film to the base material or increasing the hydrophilicity with the developer. Further, the coating film formed on the pattern has high adhesion to the pattern.
In the structural unit (a′6), a lower alkyl group or a hydrogen atom is bonded to the α-position carbon atom. The lower alkyl group bonded to the α-position carbon atom is the same as described for the structural unit (a′5), and is preferably a methyl group.
Examples of the structural unit (a′6) include a structural unit in which a monocyclic group composed of a lactone ring or a polycyclic cyclic group having a lactone ring is bonded to the ester side chain portion of the acrylate ester. At this time, the lactone ring indicates one ring containing an —O—C (O) — structure, and this is counted as the first ring. Therefore, here, in the case of only a lactone ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure.
Examples of the structural unit (a′6) include a monocyclic group obtained by removing one hydrogen atom from γ-butyrolactone, and a polycyclic group obtained by removing one hydrogen atom from a lactone ring-containing bicycloalkane. Is mentioned.
More specifically, the structural unit (a′6) is preferably at least one selected from, for example, the following general formulas (IV ″) to (VII ″).

［式（ＩＶ”）中、Ｒは上記と同じであり、Ｒ^５、Ｒ^６は、それぞれ独立に、水素原子または低級アルキル基である。］

[In formula (IV ″), R is the same as defined above, and R ⁵ and R ⁶ each independently represents a hydrogen atom or a lower alkyl group.]

［式（Ｖ”）中、Ｒは上記と同じであり、ｍは０または１である。］

[In the formula (V ″), R is the same as above, and m is 0 or 1.]

［式（ＶＩ”）中、Ｒは上記と同じである。］

[In the formula (VI ″), R is as defined above.]

［式（ＶＩＩ”）中、Ｒは上記と同じである。］

[In the formula (VII ″), R is the same as above.]

In formula (IV ″), R ⁵ and R ⁶ each independently represents a hydrogen atom or a lower alkyl group, preferably a hydrogen atom. In R ⁵ and R ⁶ , the lower alkyl group is preferably A linear or branched alkyl group having 1 to 5 carbon atoms, such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. Industrially, a methyl group is preferable.

Among the structural units represented by the general formulas (IV ″) to (VII ″), the structural unit represented by (IV ″) is inexpensive and industrially preferable, and among the structural units represented by (IV ″) R is a methyl group, R ⁵ and R ⁶ are hydrogen atoms, and the position of the ester bond between the methacrylic acid ester and γ-butyrolactone is α-methacryloyloxy-γ-butyrolactone, which is the α-position on the lactone ring. Most preferred.
The structural unit (a′6) can be used alone or in combination of two or more.
In the component (A′-12), the proportion of the structural unit (a′6) is preferably 20 to 60 mol% with respect to the total of all the structural units constituting the component (A′-12), and 20 to 50. More preferred is mol%, and most preferred is 30 to 45 mol%. Lithographic characteristics are improved by setting the value to the lower limit value or more, and balance with other structural units can be achieved by setting the upper limit value or less.

The component (A′-12) includes a polar group-containing polycyclic group in addition to the structural unit (a′5) or in addition to the structural units (a′5) and (a′6). It is preferable to have a structural unit (a′7) derived from an acrylate ester.
The structural unit (a′7) increases the hydrophilicity of the entire component (A′-12), increases the affinity with the developer, improves the alkali solubility in the exposed area, and improves the resolution. Contribute. In addition, a coating film having high adhesion to the pattern can be formed.
In the structural unit (a′7), a lower alkyl group or a hydrogen atom is bonded to the α-position carbon atom. The lower alkyl group bonded to the α-position carbon atom is the same as described for the structural unit (a′5), and is preferably a methyl group.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and an amino group, and a hydroxyl group is particularly preferable.
As the polycyclic group, among the aliphatic cyclic groups exemplified in the above-mentioned “acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group” which is the unit (a′5), from the polycyclic ones It can be appropriately selected and used.
The structural unit (a′7) is preferably at least one selected from the following general formulas (VIII ″) to (IX ″).

［式（ＶＩＩＩ”）中、Ｒは上記と同じであり、ｎは１〜３の整数である。］

[In formula (VIII ″), R is the same as described above, and n is an integer of 1 to 3.]

R in the formula (VIII ″) is the same as R in the above formulas (I ″) to (III ″).
Among these, those in which n is 1 and the hydroxyl group is bonded to the 3-position of the adamantyl group are preferable.

［式（ＩＸ”）中、Ｒは上記と同じであり、ｋは１〜３の整数である。］

[In formula (IX ″), R is the same as described above, and k is an integer of 1 to 3.]

  Among these, those in which k is 1 are preferable. Moreover, it is preferable that the cyano group has couple | bonded with 5-position or 6-position of the norbornyl group.

The structural unit (a′7) can be used alone or in combination of two or more.
In the component (A′-12), the proportion of the structural unit (a′7) is preferably 10 to 50 mol% with respect to the total of all the structural units constituting the component (A′-12). More preferably, mol% is more preferable, and 20-35 mol% is further more preferable. Lithographic characteristics are improved by setting the value to the lower limit value or more, and balance with other structural units can be achieved by setting the upper limit value or less.

  In the component (A′-12), the total of these structural units (a′5) to (a′7) is preferably 70 to 100 mol% with respect to the total of all the structural units, 80 to More preferably, it is 100 mol%.

The component (A′-12) may contain a structural unit (a′8) other than the structural units (a′5) to (a′7).
The structural unit (a′8) is not particularly limited as long as it is another structural unit that is not classified into the structural units (a′5) to (a′7).
For example, a structural unit containing a polycyclic aliphatic hydrocarbon group and derived from an (α-lower alkyl) acrylate is preferable. The polycyclic aliphatic hydrocarbon group is appropriately selected from, for example, polycyclic ones among the aliphatic cyclic groups exemplified in the aforementioned “acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group”. Can be used. In particular, at least one selected from a tricyclodecanyl group, an adamantyl group, a tetracyclododecanyl group, a norbornyl group, and an isobornyl group is preferable in terms of industrial availability. The structural unit (a′8) is most preferably an acid non-dissociable group.
Specific examples of the structural unit (a′8) include those having the following structures (X ″) to (XII ″).

（式中、Ｒは上記と同じである。）

(In the formula, R is the same as above.)

（式中、Ｒは上記と同じである。）

(In the formula, R is the same as above.)

（式中、Ｒは上記と同じである。）

(In the formula, R is the same as above.)

  When the structural unit (a′8) is included, the proportion of the structural unit (a′8) in the component (A′-12) is based on the total of all structural units constituting the component (A′-12). 1-25 mol% is preferable and 5-20 mol% is more preferable.

  The component (A′-12) is preferably a copolymer having at least the structural units (a′5), (a′6) and (a′7). As such a copolymer, for example, a copolymer comprising the structural units (a′5), (a′6) and (a′7), the structural units (a′5), (a′6), Examples thereof include a copolymer comprising (a′7) and (a′8).

The component (A′-1) can be obtained by polymerizing the monomer related to the structural unit by a known method. For example, the monomer related to each structural unit can be obtained by polymerizing by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).
The component (A′-1) is preferably 30000 or less, more preferably 20000 or less, and preferably 12000 or less, in terms of mass average molecular weight (polystyrene conversion mass average molecular weight by gel permeation chromatography, hereinafter the same). Further preferred. The lower limit may be more than 2000, and is preferably 4000 or more, and more preferably 5000 or more, from the viewpoint of suppressing pattern collapse and improving resolution.

[(A′-2) component]
As the component (A′-2), a low molecular compound having an acid dissociable, dissolution inhibiting group and a hydrophilic group is preferable. Specifically, a compound in which a part of hydrogen atoms of a hydroxyl group of a compound having a plurality of phenol skeletons is replaced with an acid dissociable, dissolution inhibiting group.
The acid dissociable, dissolution inhibiting group is not particularly limited, and examples thereof include those similar to those exemplified as the acid dissociable, dissolution inhibiting group for X or X ′.
The component (A′-2) is, for example, a part of the hydrogen atom of the hydroxyl group of a low molecular weight phenol compound known as a sensitizer or heat resistance improver for non-chemically amplified g-line or i-line resists. Those substituted with an acid dissociable, dissolution inhibiting group are preferred, and any of them can be used arbitrarily.
Examples of such low molecular weight phenol compounds include the following.
Bis (4-hydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl) propane, 2- (2,3,3) 4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-trihydroxyphenyl) propane, tris (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dimethylphenyl) -2- Hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4- Hydroxy-2,5-dimethylphenyl) -3,4-dihydroxyphenylmethane, bis (4-hydroxy-3-methylphenol) Nyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -3 , 4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene, phenol, m-cresol, p-cresol or xylenol And 2,3,4 nuclei of formalin condensates of phenols and the like. Of course, it is not limited to these.

<(B ′) component>
As the component (B ′), any conventionally known acid generator for chemically amplified resists can be appropriately selected and used. Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, and poly (bissulfonyl) diazomethanes. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  Specific examples of the onium salt acid generator include diphenyliodonium trifluoromethanesulfonate, (4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, bis (p-tert-butylphenyl) iodonium trifluoromethanesulfonate, and triphenylsulfonium trifluoromethanesulfonate. (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, (4-methylphenyl) diphenylsulfonium nonafluorobutanesulfonate, (p-tert-butylphenyl) diphenylsulfonium trifluoromethanesulfonate, diphenyliodonium nonafluorobutanesulfonate, bis (p -Tert-Butylphenyl) iodonium nonafluorobutans Honeto include triphenylsulfonium nonafluorobutanesulfonate. Of these, onium salts having a fluorinated alkyl sulfonate ion as an anion are preferable.

  Examples of oxime sulfonate compounds include α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -phenylacetonitrile, α -(Trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (propylsulfonyloxyimino) -p-methylphenylacetonitrile, α- (methyl Sulfonyloxyimino) -p-bromophenylacetonitrile and the like. Of these, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile is preferred.

  Specific examples of the diazomethane acid generator include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (2, 4-dimethylphenylsulfonyl) diazomethane and the like.

As the component (B ′), one type of acid generator may be used alone, or two or more types may be used in combination.
(B ') The usage-amount of a component shall be 1-20 mass parts with respect to 100 mass parts of (A') component, Preferably it is 2-10 mass parts. By setting it to be equal to or higher than the lower limit value of the above range, pattern formation is sufficiently performed.

<Optional component>
In the chemically amplified resist composition, a nitrogen-containing organic compound (D ′) (hereinafter referred to as “(D ′)”) is further added as an optional component in order to improve the pattern pattern shape, the stability over time. Can be blended.
Since a wide variety of components (D ′) have already been proposed, any known one can be used. However, amines, particularly secondary lower aliphatic amines and tertiary lower aliphatic amines, can be used. preferable.
Here, the lower aliphatic amine refers to an alkyl or alkyl alcohol amine having 5 or less carbon atoms, and examples of the secondary or tertiary amine include trimethylamine, diethylamine, triethylamine, di-n-propylamine, Tri-n-propylamine, tripentylamine, diethanolamine, triethanolamine, triisopropanolamine and the like can be mentioned, and tertiary alkanolamines such as triethanolamine and triisopropanolamine are particularly preferable.
These may be used alone or in combination of two or more.
The component (D ′) is usually used in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the component (A ′).

In addition, in the chemically amplified resist composition, an organic carboxylic acid is further added as an optional component for the purpose of preventing sensitivity deterioration due to the blending with the component (D ′) and improving the pattern shape, stability of placement and the like. Alternatively, phosphorus oxo acid or a derivative thereof (E ′) (hereinafter referred to as (E ′) component) can be contained. In addition, (D ') component and (E') component can also be used together, and any 1 type can also be used.
As the organic carboxylic acid, for example, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Phosphorus oxoacids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester and other phosphoric acid or derivatives thereof such as phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid- Like phosphonic acids such as di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester and derivatives thereof, phosphinic acids such as phosphinic acid, phenylphosphinic acid and their esters Among these, phosphonic acid is particularly preferable.
The component (E ′) is usually used at a ratio of 0.01 to 5.0 parts by mass per 100 parts by mass of the component (A ′).

  If desired, the chemically amplified resist composition may further contain miscible additives such as an additional resin for improving the performance of the coating film of the resist composition, a surfactant for improving the coating property, A dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent and the like can be appropriately contained.

The chemically amplified resist composition can be produced by dissolving the material in an organic solvent (S ′) (hereinafter referred to as (S ′) component).
As the component (S ′), any component can be used as long as it can dissolve each component to be used to form a uniform solution, and any one of conventionally known solvents for resist compositions can be used. Two or more types can be appropriately selected and used.
Specific examples include lactones such as γ-butyrolactone, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isopentyl ketone, 2-heptanone, ethylene glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene Polyhydric alcohols such as glycol monoacetate, propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol, or monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether of dipropylene glycol monoacetate and derivatives thereof And cyclic ethers such as dioxane, methyl lactate, ethyl lactate (EL), Methyl, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, may be mentioned methyl methoxypropionate, and esters such as ethyl ethoxypropionate. Among these, PGMEA, EL, and propylene glycol monomethyl ether (PGME) are preferable. These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
The amount of the component (S ′) used is not particularly limited, but is used in such an amount that the chemically amplified resist composition becomes a liquid having a concentration that can be applied onto the substrate.

  In the present invention, a radiation sensitive composition other than the chemically amplified resist composition may be used. Examples of the radiation-sensitive composition include resist compositions containing alkali-soluble resins such as novolak resins and hydroxystyrene resins and photosensitive components such as naphthoquinonediazide group-containing compounds. The resist composition may contain a sensitizer as necessary.

[Method of forming mold by lithography method]
In the case of using the above template forming material, a lithography method is preferably used for forming the template because a fine pattern can be formed with high accuracy.
Formation of a template by lithography can be performed by a conventionally known procedure. For example, when a chemically amplified resist composition is used, it can be performed as follows.
First, a resist composition is applied onto a substrate with a spinner or the like, and pre-baked (post-apply bake (PAB)) for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of 80 to 150 ° C. A film is formed. The thickness of the resist film cannot be generally limited, but can be determined in the range of several tens of nm to several μm, and preferably in the range of 100 to 800 nm.
Next, the resist film is selectively exposed using a commercially available exposure apparatus or the like, and then subjected to PEB (post-exposure heating) for 40 to 120 seconds, preferably 60 to 60 ° C. under a temperature condition of 80 to 150 ° C. Apply for 90 seconds. Subsequently, this is developed using an alkali developer, for example, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide. In this way, a template (resist pattern) can be obtained.

The exposure light source is not particularly limited, and may be appropriately selected and used according to the resist composition to be used. Specifically, it depends on the light absorption of the applied metal oxide nanomaterial forming composition, the film thickness of the metal oxide nanomaterial forming composition, the size of the template structure to be drawn, etc. However, in general, it can be appropriately selected within the range of far ultraviolet region of 300 nm or less, extreme ultraviolet ray of several nm, and X-ray region. For example, KrF, ArF, electron beam, EUV (Extreme Ultraviolet extreme ultraviolet light: wavelength of about 13.5 nm), X-ray, etc. are used. For example, when using the above chemically amplified resist composition, ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), electron beam, X-ray, soft X-ray, etc. preferable. On the other hand, in the case of a radiation sensitive composition other than the chemical amplification type, it is preferable to use an electron beam because a fine pattern of 200 nm or less can be formed.

The processing conditions for forming the template by the lithography method are not limited to the above, and are appropriately set according to the composition of the template forming material to be used.
Further, the template forming method is not limited to the lithography method. For example, an imprint method (a method using a fine structure created by transferring a structure to another substrate by pressing a substrate that has been finely processed in advance) can be used. The imprint method can be applied regardless of whether the mold forming material has radiation sensitivity or not.

<Hydrophilic treatment>
In the present invention, it is preferable to subject the mold surface to a hydrophilic treatment before forming a metal layer on the mold surface by electroless plating in the next step. By performing the hydrophilic treatment, the hydrophilicity of the mold surface is improved (activated), and a metal layer can be formed on the surface with high adhesion and high density by electroless plating. Moreover, it becomes easy to introduce a catalyst for electroless plating on the surface of the mold in the coating film forming step described later. Therefore, a coating film having a shape in which the shape of the mold is accurately copied or transferred can be formed.
As the hydrophilization treatment, a conventionally known method can be used, and examples thereof include oxygen plasma treatment, ozone oxidation treatment, acid-alkali treatment, and chemical modification treatment. Among these, oxygen plasma treatment is preferable because the treatment time is short and simple. Further, by performing the oxygen plasma treatment, not only the activation of the template surface but also the treatment conditions can be adjusted to adjust the height of the template and thus the height of the structure to be formed. For example, the longer the processing time of the oxygen plasma processing, the lower the mold height, and a finer structure can be obtained.
For example, when oxygen plasma treatment is used, the pressure during the oxygen plasma treatment is preferably 1.33 to 66.5 Pa (10 to 50 mtorr), and more preferably 13.3 to 26.6 Pa (100 to 200 mtorr). Moreover, 5-500W is preferable and the plasma output at the time of an oxygen plasma process has more preferable 5-50W. Further, the treatment time during the oxygen plasma treatment is preferably 1 to 30 seconds, and more preferably 2 to 5 seconds. The temperature of the oxygen plasma treatment is preferably -30 to 300 ° C, more preferably 0 to 100 ° C, and most preferably room temperature (5 to 40 ° C). The plasma apparatus used for the oxygen plasma treatment is not particularly limited. For example, a PE-2000 plasma etcher (Plasma etcher) manufactured by South Bay (South Bay Technology, USA) can be used.

<Coating film formation process>
In this step, a coating film including a metal layer formed by electroless plating is formed on the surface of the mold.
[Metal layer]
Electroless plating is performed by bringing a plating solution containing ions of a predetermined metal species into contact with the mold surface and reducing the ions (precipitating the metal), thereby forming the predetermined metal species. A metal layer is formed.
When the target metal species is a metal species that is difficult to directly electrolessly plate (for example, a noble metal such as gold), an electroless plating is performed in advance using a metal species (for example, nickel) that has a higher ionization tendency than the metal species. By forming a metal layer by the method, and then substituting the metal species of the metal layer with a target metal species, a metal layer of the target metal species can be easily formed.
The electroless plating metal species is not particularly limited, and those generally used as electroless plating metal species can be used. For example, gold, silver, copper, nickel, cobalt, tin, platinum group (palladium Platinum, rhodium, ruthenium) and the like. Among these, since plating technology is generally established, at least one selected from the group consisting of gold, silver, copper, nickel and cobalt is preferable.
In this invention, since it is desirable that it is a metal with electroconductivity, it is preferable that the metal which comprises a metal layer is at least 1 sort (s) selected from the group which consists of gold | metal | money, silver, and copper. That is, it is preferable to have any one or more of a gold layer, a silver layer, and a copper layer as the metal layer.
As the metal constituting the metal layer, cobalt is also preferable because a ferromagnetic structure can be obtained.
Reduction of ions of the metal species can be performed by a known method. Specific examples include a method of using a catalyst for reduction reaction (a catalyst in electroless plating), a method of replacing a metal having a higher ionization tendency than a plating metal, and the like.

In the present invention, it is preferable to perform the electroless plating after introducing a catalyst for electroless plating onto the surface of the mold. Since the catalyst promotes the reduction reaction of metal ions in contact with the mold surface as the core of electroless plating, a metal layer can be efficiently formed on the mold surface with high plating selectivity.
As a catalyst in electroless plating, metal fine particles, thin films, and the like are generally used. The type of metal used as a catalyst varies depending on the type of metal species used, and usually, a metal that is the same as the metal species used or more easily ionized is used as the catalyst.
As a specific example, for example, when the metal species is silver, a silver catalyst is mainly used. When the metal species is copper, a silver catalyst or a copper catalyst is mainly used. When the metal species is nickel, cobalt, gold, or the like. Palladium catalyst, tin catalyst, etc. are mainly used. As a catalyst, 1 type may be used independently and 2 or more types may be used together.
Introduction of the catalyst to the surface of the template can be performed by a known method. For example, an aqueous solution of a metal salt (for example, silver nitrate, metal chloride, etc.) serving as a catalyst is brought into contact with the template surface to adsorb the salt onto the template surface, and the salt is reduced. Thereby, metal fine particles can be introduced into the mold surface.

  1 type may be sufficient as the metal layer contained in a coating film, and 2 or more types may be sufficient as it. For example, the metal layer may have a composite layer (for example, a silver / copper composite layer made of a silver layer and a copper layer) formed by laminating two or more metal layers made of different metals. A structure in which the above metal layers are stacked via other layers (for example, a metal oxide layer, an organic / metal oxide composite layer, etc. described later) may be employed.

What is necessary is just to set the thickness of a metal layer suitably according to the dimension of the structure to form.
In the present invention, the thickness of the entire coating film is preferably 150 nm or less, more preferably 120 nm or less, still more preferably 100 nm or less, and particularly preferably 80 nm.
The lower limit of the thickness is not particularly limited, but is preferably 1 nm or more, more preferably 10 nm or more, considering the strength of the structure, self-supporting property on the substrate, coating uniformity of electroless plating, and the like. More preferably, it is 30 nm or more.

[Other layers]
The coating film may be composed of only the metal layer, or may include a layer other than the metal layer.
The layer other than the metal layer is not particularly defined unless departing from the gist of the present invention. For example, a metal oxide layer, an organic / metal oxide composite layer, an organic compound layer, and an organic / inorganic composite One or more selected from the group consisting of layers can be mentioned, and preferred are a metal oxide layer and an organic / metal oxide composite layer. 1 type may be sufficient as the said other layer contained in a coating film, and 2 or more types may be sufficient as it.
Among these, a layer containing an oxide of a metal such as silicon (metal silicon), titanium, zirconium, hafnium is preferable. In particular, it is preferable that the thin film is made of silica because it is suitable for various thin films such as an etching resistant material and an insulating film used for manufacturing a semiconductor element and a liquid crystal element.

For these other layers, a known thin film forming method such as a surface sol-gel method, an alternate adsorption method, a spin coating method, a dip coating method, an LB method (Langmuir-Blodget method), a CVD method (chemical vapor deposition method) or the like is used. Can be formed.
Further, as a material for forming these other layers, a portion corresponding to the organic component of the organic / metal oxide composite thin film in which the organic component is molecularly dispersed as described in JP-A-2002-338211 is removed. A thin film material of an amorphous metal oxide having a structured structure, a thin film layer of a polymer presenting a hydroxyl group or a carboxy group on the surface described in International Publication No. WO03 / 095193, and the hydroxyl group or the carboxy group. Thus, a thin film material composed of a metal oxide thin film layer or an organic / metal oxide composite thin film layer that is coordinated or covalently bonded to the polymer thin film layer can be preferably used. In addition, metal oxide thin films, organic compound thin films, and composites thereof described in JP-A-10-249985, JP-A-2005-205584, JP-A-2006-297575, and the like can also be preferably used.

The organic substance used in the thin film is preferably a polyanion and / or polycation which is a polymer having a charge, and the polyanion has a functional group capable of being negatively charged, such as polyglutamic acid, sulfonic acid, sulfuric acid and carboxylic acid. Preferred examples include polystyrene sulfonic acid (PSS), polyvinyl sulfate (PVS), dextran sulfate, chondroitin sulfate, polyacrylic acid (PAA), polymethacrylic acid (PMA), polymaleic acid, and polyfumaric acid. Among these, polystyrene sulfonic acid (PSS) and polymaleic acid are particularly preferable. On the other hand, the polycation has a positively charged functional group such as a quaternary ammonium group or an amino group, such as polyethyleneimine (PEI), polyallylamine hydrochloride (PAH), polydiallyldimethylammonium chloride ( Preferred examples include PDDA), polyvinyl pyridine (PVP), polylysine and the like. Among these, polyallylamine hydrochloride (PAH) and polydiallyldimethylammonium chloride (PDDA) are particularly preferable.
Furthermore, not only the polycation / polyanion described above, but a polymer compound having a hydroxyl group or a carboxy group such as polyacrylic acid, polyvinyl alcohol, polypyrrole, polysaccharides such as starch, glycogen, alginic acid, carrageenan, agarose, polyimide, phenol resin, Polyamides such as polymethyl methacrylate and acrylamide, polyvinyl compounds such as vinyl chloride, styrene polymers such as polystyrene, polythiophene, polyphenylene vinylene, polyacetylene, and derivatives and copolymers of these polymers can also be widely used.
In addition, organic small molecules can be widely used as long as they can cover the template surface, and preferred examples include surfactant molecules having long-chain alkyl, long-chain thiols, and halides. Furthermore, it has molecular recognition such as aminotriazine, cyclic imide (cyanuric acid, barbituric acid, thiobarbituric acid, thymine, etc.), guanidinium, carboxy group, phosphate group, etc. that form a network structure by hydrogen bonding. A molecule having a plurality of functional groups can also be used.
Furthermore, conductive polymers, functional polymer ions such as poly (aniline-N-propanesulfonic acid) (PAN), various deoxyribonucleic acids (DNA) and ribonucleic acids (RNA), proteins, oligopeptides, pectin, etc. It is also possible to use a charged polysaccharide or a charged biopolymer.
Furthermore, in order to increase the mechanical strength of the organic thin film, a thin film strength improving operation by a crosslinking treatment with a crosslinking material, heat, electricity, chemical treatment, or the like can be used as appropriate.

When the other layer is formed by a surface sol-gel method, for example, according to the method described in JP-A-2002-338211, a functional group that reacts with a metal compound having an alkoxy group (hereinafter sometimes referred to as “metal alkoxide”). It can be formed by repeatedly immersing in the metal alkoxide solution on the surface of the template on which the group is exposed. A metal oxide thin film is formed from a solution by stepwise adsorption of a metal alkoxide. The thickness of the metal oxide thin film fabricated by this method is controlled with nanometer level accuracy. The ultrathin metal oxide film is a thin film formed based on polycondensation of metal alkoxide, and the template coating accuracy can be handled up to the molecular level. Accordingly, a mold structure having a nanometer level shape is accurately copied.
In addition to the metal alkoxide, a metal oxide film can be formed by a similar method using a metal compound capable of generating a hydroxyl group by hydrolysis. Examples of the metal compound include a metal compound having an isocyanate group, a metal compound having a halogen atom, and a metal compound having a carbonyl group.

Examples of the metal alkoxide include titanium butoxide (Ti (O—nBu) ₄ ), zirconium propoxide (Zr (O—nPr) ₄ ), aluminum butoxide (Al (O—nBu) ₃ ), niobium butoxide (Nb (O -NBu) ₅ ), metal alkoxide compounds other than rare earth metals such as silicon tetramethoxide (Si (O-Me) ₄ ), boron ethoxide (B (O-Et) ₃ ); lanthanide isopropoxide (Ln (O— iPr) ₃ ), metal alkoxide compounds of rare earth metals such as yttrium isopropoxide (Y (O-iPr) ₃ ); double alkoxide compounds such as barium titanium alkoxide (BaTi (OR ⁶⁰ ) _X3 ) R ⁶⁰ 'is a lower alkyl group of 1 to 5 carbon atoms, _{X 3} is an integer from 2 to 4 There); methyltrimethoxysilane _{(MeSi (O-Me) 3} ), such as diethyl diethoxy silane _{(Et 2 Si (O-Et} ) 2), having two or more alkoxy groups, and other than an alkoxy group Examples thereof include metal alkoxide compounds having an organic group; metal alkoxide compounds having a ligand such as acetylacetone and having two or more alkoxy groups.
Further, fine particles of alkoxide sol or alkoxide gel obtained by adding a small amount of water to the metal alkoxides and partially hydrolyzing and condensing them can also be used.
Furthermore, a binuclear or cluster type alkoxide compound having a plurality of or plural kinds of metal elements such as titanium butoxide tetramer (C ₄ H ₉ O [Ti (OC ₄ H ₉ ) ₂ O] ₄ C ₄ H ₉ ) In addition, a polymer based on a metal alkoxide compound cross-linked one-dimensionally through an oxygen atom is also included in the metal alkoxides.

Examples of the metal compound having an isocyanate group include compounds having two or more isocyanate groups represented by the general formula “M (NCO) _X0 ” (M is a metal atom, where X ₀ is 2 to 4). Integer). Specifically, tetraisocyanate silane (Si (NCO) ₄ ), titanium tetraisocyanate (Ti (NCO) ₄ ), zirconium tetraisocyanate (Zr (NCO) ₄ ), aluminum triisocyanate (Al (NCO) ₃ ), etc. Can be mentioned.
As the metal compound having a halogen atom, the general formula “M (X ₁ ) _{n ″} ” (M is a metal atom, X ₁ is a kind selected from a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, n "Is an integer of 2 to 4), and a halogenated metal compound having 2 or more (preferably 2 to 4) halogen atoms is exemplified. The compound having a halogen atom may be a metal complex. Specific examples include tetrachlorotitanium (TiCl ₄ ), tetrachlorosilane (SiCl ₄ ), etc. Further, examples of the metal complex include cobalt chloride (CoCl ₂ ).
Examples of the metal compound having a carbonyl group include metal carbonyl compounds such as titanium oxoacetyl acetate (TiO (OCOCH ₂ COCH ₃ ) ₂ ) and pentacarbonyl iron (Fe (CO) ₅ ), and multinuclear clusters thereof.

Among these, since a metal oxide film having particularly high activity and high etching resistance can be easily formed without particularly performing heat treatment, two or more isocyanate groups and / or halogen atoms (preferably 2 to 4) silicon compounds are preferred.
The number of silicon in one molecule of the silicon compound may be 1 or 2 or more, preferably 1. Especially, the compound represented by the following general formula (w-1) is preferable.
SiW _a (w-1)
In the formula (w-1), a is an integer of 2 to 4, and is preferably 4.
W is an isocyanate group (NCO group) or a halogen atom, and a plurality of W may be the same or different from each other.
The halogen atom of W is the same as the halogen atom in the metal compound having a halogen atom, and is preferably a chlorine atom. Among these, an isocyanate group is preferable.

<Mold removal process>
In this step, part or all of the template is removed while leaving part or all of the coating film. At this time, at least part of the coating film remains on the substrate as it is, and the remaining coating film constitutes part or all of the structure.
As a method for removing the template, conventionally known methods for removing the template can be widely adopted. In particular, from the viewpoint of ease of control, it is preferably carried out by at least one treatment method selected from the group consisting of plasma, ozone oxidation, elution and firing, and more preferably plasma treatment.

The processing method and processing conditions in the case of using plasma processing can be appropriately determined according to the components of the template to be removed.
For example, the time, pressure, output, and temperature during the plasma treatment can be appropriately determined according to the type, size, plasma source, and the like of the component to be removed.
As the plasma source for the plasma treatment, various gases such as oxygen gas, hydrogen gas, and nitrogen gas can be used. Among these, oxygen plasma treatment using oxygen gas or hydrogen plasma treatment using hydrogen gas is preferable, and hydrogen plasma treatment is particularly preferable because oxidation of the formed metal structure can be prevented.
For example, when oxygen plasma treatment is used, the pressure during the oxygen plasma treatment is preferably 1.33 to 66.5 Pa (10 to 500 mtorr), and more preferably 13.3 to 26.6 Pa (100 to 200 mtorr). It is. The plasma output during the oxygen plasma treatment is 5 to 500 W, preferably 10 to 50 W. The treatment time during the oxygen plasma treatment is 5 minutes to several hours, preferably 5 to 60 minutes. The temperature of the oxygen plasma treatment is a low temperature, preferably -30 to 300 ° C, more preferably 0 to 100 ° C, and most preferably room temperature (5 to 40 ° C). The plasma apparatus used for the oxygen plasma treatment is not particularly limited. For example, a PE-2000 plasma etcher (Plasma etcher) manufactured by South Bay (South Bay Technology, USA) can be used.
For example, when hydrogen plasma treatment is used, the pressure during the hydrogen plasma treatment is preferably 1.33 to 66.5 Pa (10 to 500 mtorr), and more preferably 13.3 to 26.6 Pa (100 to 200 mtorr). It is. The plasma output during the hydrogen plasma treatment is 5 to 500 W, preferably 10 to 50 W. The treatment time during the hydrogen plasma treatment is suitably 5 minutes to several hours, preferably 5 to 60 minutes. Moreover, the temperature of hydrogen plasma treatment is low temperature, Preferably it is -30-300 degreeC, More preferably, it is 0-100 degreeC, Most preferably, it is room temperature (5-40 degreeC). The plasma apparatus used for the hydrogen plasma treatment is not particularly limited. For example, a PE-2000 plasma etcher (Plasma etcher) manufactured by South Bay (South Bay Technology, USA) can be used.

  The conditions for using the ozone oxidation treatment can be appropriately determined according to the component of the mold to be removed and the apparatus to be used. For example, the pressure during the ozone oxidation treatment is suitably in the range of atmospheric pressure to 13.3 Pa (100 mTorr), preferably in the range of 133.3 to 133333.3 Pa (0.1 to 100 torr). The ozone oxidation treatment time can be several minutes to several hours, preferably 5 to 60 minutes. The treatment temperature is room temperature to 600 ° C., preferably room temperature to 400 ° C.

  As conditions for using the elution treatment, a known elution method can be appropriately employed depending on the components of the template to be removed. For example, when the template is formed using a template-forming material containing an organic compound having a molecular weight of 500 or more, the template can be eluted by using an organic solvent such as methanol, ethanol, and acetone. it can.

  The treatment conditions when the firing treatment is used are preferably 100 to 1000 ° C., preferably 300 to 500 ° C. in the air atmosphere, and 30 seconds to several hours, preferably 1 to 60 minutes. In addition, when using a base material that is easily oxidized such as silicon, it is preferable to perform a baking treatment in a nitrogen atmosphere in order to prevent the base material from being oxidized. The conditions for the firing treatment in nitrogen are the same as in the air atmosphere.

  At this time, the mold may be completely removed or a part thereof may be removed. When removing a part, it is preferable to remove 1 to 99% of the whole, and it is more preferable to remove 5 to 95%. When a part of the template is removed in this way, the resulting structure is obtained as a coating film-template complex containing a part of the template. The structure may be used as it is or may be further processed.

Further, when a plurality of molds are provided, the steps of removing these molds may be performed simultaneously or separately. When performing separately, it is preferable to remove sequentially from the inner side or lower side.
Furthermore, when a plurality of templates are provided, it is not necessary to remove all the templates, and all of them may be completely removed or only a part of them may be removed. When removing a part, it is preferable to remove 1 to 99% of the whole, and it is more preferable to remove 5 to 95%. When a part of the template is removed in this way, the structure is obtained as a coating film-template complex partly including the template, but the nanostructure in such a state may be used as it is. .

When the coating film includes, in addition to the metal layer, a layer containing an organic compound (for example, the organic / metal oxide composite layer) as another layer, in the template removal step, the organic layer is removed simultaneously with the removal of the template. Part or all of the organic compound in the layer containing the compound can be removed.
When part or all of the organic compound is removed, a structure in which a part corresponding to the organic compound is removed is formed. That is, a structure having voids corresponding to the molecular shape of the removed organic compound is formed.
Specifically, for example, a) a structure in which a portion corresponding to the organic compound contained in the organic / metal oxide composite layer is left as it is, and b) an organic compound contained in the organic / metal oxide composite layer. A structure having a gap in the vicinity of the portion to be centered; c) a portion corresponding to the organic compound contained in the organic / metal oxide composite layer or the vicinity thereof is a void; For example, a structure in which the parts are connected to each other to form a mesh.
A structure having such voids can be used, for example, as a permeable membrane selective to a molecular structure.
If necessary, a step of removing the organic compound in the organic / metal oxide composite layer may be provided separately from the template removing step. For example, a process of performing processing such as plasma, ozone oxidation, elution, and baking under processing conditions different from the mold removal process may be provided.

<The process of removing a part of coating film>
In this invention, it is preferable to perform the process of removing a part of said coating film before the said template removal process.
In this case, the coating film is preferably removed so that a part of the mold is exposed. Thereby, the mold can be easily removed by etching or the like.

Further, after the template removal step, a step of removing a part of the coating film may be performed. In particular, in the template removal step, after removing a part of the template, a part of the coating film is removed. Is preferably removed.
In the present invention, when a part of the coating film is removed after the part of the template is removed, the coating film is preferably removed so that a part of the template is exposed. Thereby, the mold can be easily removed by etching or the like.

As a method for removing a part of the coating film, any method can be used as long as it can process the metal layer, considering the type of material constituting the coating film, and considering the type of the mold as necessary. Any known method may be employed. Examples of the known method include etching, chemical treatment, physical peeling, and polishing. Among these, etching is preferable because it has few processing steps and is simple, and dry etching using argon, oxygen, or the like is particularly preferable.
The ratio of the coating film to be removed is not particularly limited, and is preferably 1 to 99% of the whole, and more preferably 5 to 95% of the whole.

The step of removing a part of the coating film is not particularly limited, but it is preferable to remove one plane including a part of the coating film. In this case, the one plane may be parallel to the substrate, may be perpendicular, or may have an appropriate angle of inclination. Of course, it is needless to say that other removal methods may be used.
In this step, it is particularly preferable to remove the upper end portion of the coating film. In particular, when a mold having a rectangular longitudinal cross-section, for example, a rectangular line structure, a hole structure, a cylindrical structure, or the like is used as the casting mold, the top surface (referred to as the upper surface in this specification) among the coating films provided on the surface. It is preferable to remove the upper end including
As a specific example, for example, when a mold having a hole structure is used, a coating film is formed on the mold surface, the upper end of the coating film is removed, and then the mold is removed. Only the side wall portion of the coating film remains. As a result, a cylinder-shaped structure having the same outer diameter as the inner diameter of the hole is obtained.
For example, when a rectangular line structure is used as a mold, a coating film is formed on the surface of the mold, and after removing the upper end portion of the coating film, the mold is removed. Only the side wall portion remains. As a result, a structure having a line shape (a line in which the width is the thickness of the coating film and the height is the height of the remaining side wall portion) is formed on the base material. The structure has a self-supporting property.
In addition, the height of the structure to be formed can be adjusted by adjusting how much the upper end portion is removed. For example, the greater the removal amount of the upper end portion of the coating film, the lower the height of the structure to be formed, and a finer structure can be obtained.
As described above, when the upper end portion of the coating film is removed and the side wall portion of the coating film is used, a nano-level structure can be easily obtained without using a very fine template.

  In the present invention, part of the coating film may be removed and part or all of the template may be removed continuously or simultaneously. For example, when a rectangular cross-section mold is used as a rectangular cross-section mold, the top surface of the coating film is removed by one etching process, and the upper end of the side wall of the coating film and the inner side thereof are subsequently removed. Part or all of the mold can be removed.

  As described above, a structure composed of a part or all of the coating film or a part or whole of the coating film and a part of the template is formed on the substrate.

Hereinafter, although preferred embodiment of the manufacturing method (1) of this invention is described along drawing, it cannot be overemphasized that other embodiment is not excluded.
“First Embodiment”
FIG. 1 shows a flowchart of the first embodiment.
In this embodiment, first, a mold 11 having a rectangular line structure is formed on the substrate 1 (1-1). Next, a catalyst (metal fine particles) 15 is introduced onto the surface of the mold 11 (1-2). And the electroless plating is given to the surface of the casting_mold | template 11, and the coating film 21 which consists of one metal layer is formed (1-3). Next, the upper end part of the coating film 21 is removed on a surface parallel to the base material to expose the mold 11 (1-4). At this time, a part of the mold 11 may be removed together with the upper end portion of the coating film 21. Finally, the mold 11 is removed. If it does so, only the side wall part 21a of the coating film 21 will remain on the base material 1, and a fine structure will be formed (1-5).

In this embodiment, the dimension of the structure obtained can be controlled by controlling the film thickness of the coating film 21 in the step of providing the coating film 21 on the surface of the mold 11. And by determining the shape of the mold 11 as appropriate, an extremely fine structure can be manufactured. For example, a nanostructure composed of a coating film having a width of several nanometers to several tens of nanometers can be obtained. Moreover, the control of the width is easy.
Furthermore, in the present embodiment, a high aspect ratio structure can be formed on the substrate in an upright state with excellent self-supporting properties. In the present embodiment, the structure can be formed with a high aspect ratio of, for example, an aspect ratio (height / width) of 5/1 or more, and further 10/1 or more. The upper limit of the aspect ratio is preferably (height / width) of 300/1 or less, more preferably 100/1 or less, and particularly preferably 10/1 or less, considering self-supporting properties on the substrate.

  Note that the mold 11 for coating the coating film 21 is not necessarily fine, and may be, for example, a centimeter order structure. By appropriately setting the conditions for forming the coating film 21 and the conditions for removing the template 11, a nanostructure can be produced in the same manner as described above. That is, a structure having a width on the order of nanometers can be produced.

“Second Embodiment”
FIG. 2 is a flowchart of the second embodiment. This embodiment is an example of forming a structure composed of two metal layers.
In this embodiment, first, the mold 11 is formed on the substrate 1 (2-1), and the first metal layer 22 is formed on the surface of the mold 11 (2-2). Next, the second metal layer 23 is formed on the surface of the first metal layer 22 (2-3). As a result, a coating film (composite film) having a laminated structure of the first metal layer 22 and the second metal layer 23 is formed on the surface of the mold 11. At this time, one of the first metal layer 22 and the second metal layer 23 may be a layer other than the metal layer.
Next, the upper end portion of the composite film is removed on a plane parallel to the base material to expose the mold 11 (2-4). At this time, a part of the mold 11 may be removed together with the upper end portion of the composite film. Finally, the mold 11 is removed. If it does so, only the side wall part (22a and 23a) of a composite film will remain on the base material 1, and a fine structure will be formed (2-5).

In the above embodiment, the step of removing the upper end portion of the coating film and the step of completely removing the template are performed separately, but these may be performed simultaneously.
In the above embodiment, the template is completely removed, but a part may be removed and a part may be left.
In the above embodiment, the template is removed after removing a part of the coating film. However, a part or all of the template may be removed before removing the coating film. In such a case, the template can be removed by elution, firing or the like. Usually, since the metal layer formed by electroless plating is a porous film, the template can be removed by, for example, performing the elution process described above and dissolving the template with an organic solvent.
In the above embodiment, a part of the coating film is removed. However, in the manufacturing method (1) of the present invention, a part of the coating film may not be removed. In this case, for example, when a template having a rectangular line structure is employed as in the above-described embodiment, the resulting structure has a U-shaped cross section. A tunnel structure is formed thereon.

The method for producing a structure according to the second aspect of the present invention (hereinafter sometimes referred to as the production method (2) of the present invention) is carried out by electroless plating at least on the surface of a mold provided on a substrate. A structure is formed on the substrate by performing a step of forming a coating film including a metal layer to be formed and a step of removing a part of the coating film.
The production method (2) of the present invention does not require the “template removal step” in the production method (1) of the present invention, but the “process for removing part of the coating film”. It is different from the manufacturing method (1) of the invention.
In the production method (2) of the present invention, the step of forming the coating film and the step of removing a part of the coating film are respectively the “coating film forming step” in the production method (1) of the present invention. And “the step of removing a part of the coating film”.

In the production method (2) of the present invention, it is preferable to perform a step of removing a part or all of the template before and / or after removing a part of the coating film.
This step can be performed in the same manner as the “template removal step” in the production method (1) of the present invention.
In the production method (2) of the present invention, the “template removal step” is not an essential step, but a finer structure can be obtained by performing this step.

According to the manufacturing method (1) or (2) of the present invention, a fine structure including a metal layer can be easily manufactured. For example, on a substrate, a nanostructure composed of a film having a width of several nanometers to several hundred nanometers, for example, a nanostructure having a height of 5 to 500 nm and a width of 2 to 100 nm, A nanostructure having a height of 10 to 300 nm and a width of 1 to 50 nm can be easily produced.
Such nanostructures are expected to be applied to various fields such as electronic devices, magnetic devices, molecular sensors, metal catalysts, actuators, separating agents, adsorbents, and polarizing films.

≪Structure≫
The structure of the present invention is produced by the production method (1) or (2) of the present invention.
The shape of the structure is not particularly limited. As a specific example, for example, a line, a cylinder or other three-dimensional structure, a network structure, a composite structure, a repeating structure, or the like can be adopted.
Since the production method (1) or (2) of the present invention can easily produce a nanostructure as described above, the structure of the present invention is preferably a nanostructure.

(Example 1: Production of silver nanoline)
First, a template was formed by the following procedure by lithography.
A positive resist composition for KrF excimer laser (trade name: TDUR-P015, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied onto an 8-inch silicon wafer substrate by spin coating, and prebaked at 90 ° C. for 90 seconds. Thus, a resist film having a thickness of 400 nm was formed. The resist film is exposed through a mask pattern using a KrF excimer laser exposure machine NSR-S205 (NA = 0.75) manufactured by Nikon, and post-baked (PEB) under conditions of 110 ° C. for 90 seconds. Thereafter, the resist pattern (template) was formed by developing for 60 seconds using an aqueous 2.38 mass% tetramethylammonium hydroxide solution.
The shape of the mold was a rectangular line structure having a width of about 600 nm and a height of about 400 nm.

A silicon wafer substrate having a rectangular line structure having a width of about 600 nm and a height of about 400 nm formed as described above is subjected to oxygen plasma treatment (pressure 24 Pa, power 10 W, treatment time 3 seconds, treatment temperature 25 ° C.) and a mold. The surface of was activated.
Next, after being immersed in 10 ml of an aqueous silver nitrate solution (1M) for 5 minutes, it was immersed in deionized water for 1 minute and dried in a nitrogen gas stream. Next, the substrate was immersed in 10 ml of an aqueous sodium borohydride solution (10 mM) for 1 minute, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream. By performing this series of operations five times, fine silver particles (catalyst) were introduced onto the template surface.
Next, aqueous ammonia (0.2 M) was added to 5 ml of an aqueous silver nitrate solution (0.15 M) until the brown precipitate disappeared (about 5 ml) to prepare a silver nitrate / ammonia mixed aqueous solution. 1 ml of this solution was mixed with 1 ml of glucose solution (water: methanol = 7: 3; glucose concentration: 0.7 g / l), and the substrate prepared in the previous operation was immersed (solution temperature 25 ° C., immersion time 5 minutes). Then, silver electroless plating was performed to form a silver thin film on the mold surface.
The electroless-plated substrate was subjected to an etching process using argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 1 minute) using an RIE apparatus, and the upper surface portion of the silver thin film was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (hydrogen plasma etching; pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.), and the mold was removed. By the above operation, a silver nanoline structure composed of the side surface portion of the silver thin film was formed on the substrate.

This silver nanoline was examined with a scanning electron microscope. FIG. 3 shows a scanning electron microscope image of the silver nanoline. FIG. 3A is a longitudinal sectional perspective view, and FIG. 3B is a partially enlarged view of FIG.
As shown in FIG. 3, it was recognized that silver nanolines having a line width of about 60 nm and a height of about 300 nm were formed on the substrate. Moreover, this silver nanoline has a high aspect ratio with respect to line width, and it turns out that a silver line is hold | maintained by self-support.

(Example 2: Production of copper nanoline)
As in Example 1, an oxygen plasma treatment (pressure 24 Pa, power 10 W, treatment time 3 seconds, treatment temperature 25 ° C.) was applied to a silicon wafer substrate on which a rectangular line structure having a width of about 600 nm and a height of about 400 nm was formed. The surface of the template was activated.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, an appropriate amount of a 0.1 mol / l sodium hydroxide aqueous solution is added to about 90 ml of a mixed aqueous solution containing copper chloride, boric acid, disodium ethylenediaminetetraacetate, and dimethylamine borane at the following final concentrations. The pH was adjusted to 7.0 and water was added to bring the total solution to 100 ml. The final concentration of each component is copper chloride (0.05M), boric acid (0.1M), disodium ethylenediaminetetraacetate (0.05M), dimethylamine borane (0.1M). The substrate was immersed in this solution (solution temperature: 50 ° C., immersion time: 10 minutes), and copper electroless plating was performed to form a copper thin film on the mold surface.
The electroless-plated substrate is etched with argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 1 minute, treatment temperature 25 ° C.) using an RIE apparatus, and the upper surface portion of the copper thin film Was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.) to remove the mold. With the above operation, a copper nanoline structure consisting of the side surface portion of the copper thin film was formed on the substrate.

This copper nanoline was examined with a scanning electron microscope. FIG. 4 shows a scanning electron microscope image of this copper nanoline. 4A is a longitudinal sectional perspective view, and FIG. 4B is a partially enlarged view of FIG.
As shown in FIG. 4, it was recognized that a copper nanoline having a line width of about 60 nm and a height of about 300 nm was formed on the substrate. Moreover, this copper nanoline has a high aspect ratio with respect to line width, and it turns out that the copper line is hold | maintained by self-support.

(Example 3: Production of silver / copper composite nanoline)
As in Example 1, an oxygen plasma treatment (pressure 24 Pa, power 10 W, treatment time 3 seconds, treatment temperature 25 ° C.) was applied to a silicon wafer substrate on which a rectangular line structure having a width of about 600 nm and a height of about 400 nm was formed. The surface of the template was activated.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, silver electroless plating was performed in the same manner as in Example 1 to form a silver thin film on the mold surface.
Next, copper electroless plating was performed in the same manner as in Example 2 to form a copper thin film on the silver thin film. As a result, a silver / copper composite thin film was formed on the mold surface.
This electroless-plated substrate is subjected to an etching process using an RIE apparatus (gas flow rate 30 sccm, pressure 10 pa, power 300 W, processing time 2 minutes, processing temperature 25 ° C.), and a silver / copper composite thin film The upper surface portion of was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.) to remove the mold. By the above operation, a silver / copper composite nanoline structure composed of side portions of the silver / copper composite thin film was formed on the substrate.

This silver / copper composite nanoline was examined with a scanning electron microscope. FIG. 5 shows a scanning electron microscope image of the silver / copper composite nanoline. Fig.5 (a) is a longitudinal cross-sectional perspective view, (b) is the elements on larger scale of (a).
As shown in FIG. 5, it was confirmed that a silver / copper composite nanoline having a line width of about 120 nm and a height of about 300 nm was formed on the substrate. It can also be seen that the silver / copper composite nanoline is held in a self-supporting manner.

(Example 4: Production of silver cylinder)
A hole structure (mold) having an inner diameter of about 600 nm and a height of about 400 nm was formed on a silicon wafer substrate in the same manner as in Example 1 except that the mask pattern used was changed.
The silicon wafer substrate on which the hole structure was formed was subjected to oxygen plasma treatment (pressure 24 Pa, power 10 W, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, silver electroless plating was performed in the same manner as in Example 1 to form a silver thin film on the mold surface.
The electroless-plated substrate was subjected to an etching process using argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 1 minute) using an RIE apparatus, and the upper surface portion of the silver thin film was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.) to remove the mold. The silver cylinder structure which consists of a side part of a silver thin film was formed on the board | substrate by the above operation.

This silver cylinder was examined with a scanning electron microscope. FIG. 6 shows a scanning electron microscope image of this silver cylinder. FIG. 6 is a longitudinal sectional view of one silver cylinder.
As shown in FIG. 6, it was recognized that a silver cylinder having a peripheral wall thickness of about 60 nm and a height of about 300 nm was formed on the substrate.

(Example 5: Production of copper cylinder)
In the same manner as in Example 4, a silicon wafer substrate on which a hole structure having an inner diameter of about 600 nm and a height of about 400 nm was formed was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) and a mold. The surface of was activated.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, copper electroless plating was performed in the same manner as in Example 2 to form a copper thin film on the mold surface.
The electroless-plated substrate is etched with argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 1 minute, treatment temperature 25 ° C.) using an RIE apparatus, and the upper surface portion of the copper thin film Was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.) to remove the mold. The copper cylinder structure which consists of a side part of a copper thin film was formed on the board | substrate by the above operation.

This copper cylinder was examined with a scanning electron microscope. FIG. 7 shows a scanning electron microscope image of this copper cylinder. FIG. 7 is a longitudinal sectional view of one copper cylinder.
As shown in FIG. 7, it was recognized that a copper cylinder having a wall thickness of about 60 nm and a height of about 300 nm was formed on the substrate.

(Example 6: Manufacture of silver / copper composite cylinder)
In the same manner as in Example 4, a silicon wafer substrate on which a hole structure having an inner diameter of about 600 nm and a height of about 400 nm was formed was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) and a mold. The surface of was activated.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, silver electroless plating was performed in the same manner as in Example 1 to form a silver thin film on the mold surface.
Next, copper electroless plating was performed in the same manner as in Example 2 to form a copper thin film on the silver thin film. As a result, a silver / copper composite thin film was formed on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 2 minutes, treatment temperature 25 ° C.) using a RIE apparatus, and a silver / copper composite thin film The upper surface portion of was removed. Subsequently, the substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes, treatment temperature 25 ° C.) to remove the mold. With the above operation, a silver / copper composite cylinder structure composed of side portions of the silver / copper composite thin film was formed on the substrate.

This silver / copper composite cylinder was examined with a scanning electron microscope. FIG. 8 shows a scanning electron microscope image of this silver / copper composite cylinder. FIG. 8 is a longitudinal sectional view of one silver / copper composite cylinder.
As shown in FIG. 8, it was recognized that a silver / copper composite cylinder having a peripheral wall thickness of about 120 nm and a height of about 300 nm was formed on the substrate.

(Example 7: Production of silver nanoline (height reduction))
First, a template was formed by the following procedure by lithography.
A positive resist composition for KrF excimer laser (trade name: TDUR-P015, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied onto an 8-inch silicon wafer substrate by spin coating, and prebaked at 90 ° C. for 90 seconds. Thus, a resist film having a thickness of 700 nm was formed. The resist film is exposed through a mask pattern using a KrF excimer laser exposure machine NSR-S205 (NA = 0.75) manufactured by Nikon, and post-baked (PEB) under conditions of 110 ° C. for 90 seconds. Thereafter, the resist pattern (template) was formed by developing for 60 seconds using an aqueous 2.38 mass% tetramethylammonium hydroxide solution.
The shape of the mold was a rectangular line structure having a width of about 400 nm and a height of about 700 nm.

A silicon wafer substrate having a rectangular line structure with a width of about 400 nm and a height of about 700 nm formed as described above is subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 4 minutes, treatment temperature 25 ° C.) to form a rectangle. The height of the line structure was reduced to about 200 nm.
Next, in the same manner as in Example 1, fine silver particles (catalyst) were introduced onto the mold surface.
Next, silver electroless plating was performed in the same manner as in Example 1 to form a silver thin film on the mold surface.
The electroless-plated substrate is etched with argon gas (gas flow rate 30 sccm, pressure 10 Pa, power 300 W, treatment time 1 minute, treatment temperature 25 ° C.) using an RIE apparatus, and the upper surface portion of the silver thin film Was removed. Subsequently, this substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes), and the mold was removed. The silver nanoline structure which consists of a side part of a silver thin film was formed on the board | substrate by the above operation.

This silver nanoline was examined with a scanning electron microscope. FIG. 9 shows a scanning electron microscope image of the silver nanoline. Fig.9 (a) is a longitudinal cross-sectional perspective view, (b) is the elements on larger scale of (a).
As shown in FIG. 9, it was confirmed that silver nanolines having a line width of about 60 nm and a height of about 150 nm were formed on the substrate.

(Example 8: Production of silver nanoline single wire, conductivity evaluation)
A rectangular line structure mold having a width of about 5 mm and a height of about 600 nm in the same manner as in Example 7 except that the mask pattern to be used was changed on a silicon wafer substrate covered with a SiO ₂ thermal oxide film having a surface of 500 nm. Formed. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, after being immersed in 10 ml of an aqueous silver nitrate solution (1M) for 3 minutes, it was immersed in deionized water for 1 minute and dried in a nitrogen gas stream. Next, the substrate was immersed in 10 ml of an aqueous sodium borohydride solution (10 mM) for 1 minute, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream. This series of operations was performed three times.
Next, aqueous ammonia (0.2 M) was added to 5 ml of an aqueous silver nitrate solution (0.15 M) until the brown precipitate disappeared (about 5 ml) to prepare a silver nitrate / ammonia mixed aqueous solution. 1 ml of this solution was mixed with 1 ml of glucose solution (water: methanol = 7: 3; glucose concentration 0.7 g / l), and the substrate prepared in the previous operation was immersed (solution temperature 25 ° C., immersion time 2 minutes) Silver electroless plating was performed to form a silver thin film on the mold surface.
The electroless-plated substrate was subjected to an etching process using argon gas (gas flow rate 30 sccm, pressure 10 pa, power 300 W, treatment time 50 seconds) using an RIE apparatus, and the upper surface portion of the silver thin film was removed. Subsequently, this substrate was subjected to etching treatment with hydrogen gas (pressure 27 Pa, power 50 W, treatment time 40 minutes), and the mold was removed. The silver nanoline which consists of a side part of a silver thin film by the above operation was obtained.

This silver nanoline was examined with a scanning electron microscope. FIG. 10 shows a scanning electron microscope image (longitudinal sectional perspective view) of the silver nanoline. As shown in FIG. 10, silver nanolines having a line width of about 40 nm and a height of about 300 nm were formed on the substrate.
Further, both ends of the silver nanoline were connected to a gold fine wire with a silver paste, and the gold fine wire was connected to a potentiostat (manufactured by Princeton Applied Research, trade name: PARSTAT 2263) to examine electrical conductivity. The result is shown in FIG.
From the above results, it was confirmed that the silver nanoline had a high aspect ratio with respect to the line width and high electrical conductivity.

(Example 9: Production of nickel nanoline (height reduction))
A rectangular line structure mold having a width of about 400 nm and a height of about 700 nm was formed on a silicon wafer substrate in the same manner as in Example 7. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 minutes, treatment temperature 25 ° C.) to reduce the height of the rectangular line structure to about 500 nm.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, about 10 ml of a mixed aqueous solution containing nickel chloride (0.13 M), anhydrous trisodium citrate dihydrate (0.034 M), and dimethylamine borane (0.025 M) was prepared. The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a nickel thin film on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 10 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, this substrate was subjected to an etching process using oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The nickel nanoline which consists of a side part of a nickel thin film was obtained by the above operation.

This nickel nanoline was examined with a scanning electron microscope. FIG. 12 shows a scanning electron microscope image of the nickel nanoline. 12A is a longitudinal sectional perspective view, and FIG. 12B is a partially enlarged view of FIG.
As shown in FIG. 12, it was recognized that nickel nanolines having a line width of about 30 nm and a height of about 500 nm were formed on the substrate. The nickel nanoline has a high aspect ratio with respect to the line width, and it can be seen that the nickel nanoline is held in a self-supporting manner.

(Example 10: Production of cobalt nanoline (height reduction), magnetic evaluation)
A rectangular line structure mold having a width of about 400 nm and a height of about 700 nm was formed on a silicon wafer substrate in the same manner as in Example 7. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 minutes, treatment temperature 25 ° C.) to reduce the height of the rectangular line structure to about 500 nm.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, 2M aqueous sodium hydroxide solution was added to about 10 ml of a mixed aqueous solution containing a predetermined amount of cobalt sulfate heptahydrate, anhydrous trisodium citrate dihydrate, dimethylamine borane, ammonium sulfate, phosphoric acid and sodium tartrate dihydrate. An appropriate amount was added to adjust the solution pH to 9.0, and water was added to make the total amount of the solution 20 ml. The final concentration of each component is cobalt sulfate heptahydrate (0.1M), anhydrous trisodium citrate dihydrate (0.05M), dimethylamine borane (0.025M), ammonium sulfate (0.2M), phosphorus Acid (0.06M), sodium tartrate dihydrate (0.2M). The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a cobalt thin film on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 8 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, this substrate was subjected to an etching process using oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The cobalt nanoline which consists of a side part of a cobalt thin film by the above operation was obtained.

The cobalt nanoline was examined with a scanning electron microscope. FIG. 13 shows a scanning electron microscope image (longitudinal sectional perspective view) of this cobalt nanoline. As shown in FIG. 13, cobalt nanolines having a line width of about 30 nm and a height of about 300 nm were formed on the substrate.
Moreover, the magnetic measurement of this cobalt nanoline was performed with the superconducting magnetic flux quantum interferometer (SQUID). The result is shown in FIG.
From the above results, it was confirmed that the cobalt nanoline has a high aspect ratio with respect to the line width and has ferromagnetism.

(Example 11: Production of gold nanoline (height reduction))
A rectangular line structure mold having a width of about 400 nm and a height of about 700 nm was formed on a silicon wafer substrate in the same manner as in Example 7. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 minutes, treatment temperature 25 ° C.) to reduce the height of the rectangular line structure to about 500 nm.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, about 10 ml of a mixed aqueous solution containing nickel chloride (0.13 M), anhydrous trisodium citrate dihydrate (0.034 M), and dimethylamine borane (0.025 M) was prepared. The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a nickel thin film on the mold surface. Further, this substrate was immersed in an aqueous solution of gold displacement plating (Hitachi Kasei Co., Ltd., trade name: HSG-500, water: HGS-500 = 9: 1) containing potassium cyanide gallate (0.024M) (solution temperature 70 C., immersion time 8 minutes), gold displacement plating was performed, and the nickel thin film on the mold surface was replaced with a gold thin film.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 3 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, it was immersed in an aqueous nitric acid solution (30 vol%) to remove nickel remaining without being replaced. Further, this substrate was etched with oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The gold nanoline which consists of a side part of a gold thin film by the above operation was obtained.

This gold nanoline was examined with a scanning electron microscope. FIG. 15 shows a scanning electron microscope image of this gold nanoline. FIG. 15A is a longitudinal sectional perspective view, and FIG. 15B is a partially enlarged view of FIG.
As shown in FIG. 15, it was recognized that gold nanolines having a line width of about 30 nm and a height of about 400 nm were formed on the substrate. The gold nanoline has a high aspect ratio with respect to the line width, and it can be seen that the nickel nanoline is retained in a self-supporting manner.

(Example 12: Production of nickel nanocylinder)
A hole structure mold having a width of about 500 nm and a height of about 600 nm was formed on a silicon wafer substrate in the same manner as in Example 7 except that the mask pattern used was changed. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, about 10 ml of a mixed aqueous solution containing nickel chloride (0.13 M), anhydrous trisodium citrate dihydrate (0.034 M), and dimethylamine borane (0.025 M) was prepared. The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a nickel thin film on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 10 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, this substrate was subjected to an etching process using oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The nickel nanocylinder which consists of a side part of a nickel thin film by the above operation was obtained.

The nickel nanocylinder was examined with a scanning electron microscope. FIG. 16 shows a scanning electron microscope image of the nickel nanocylinder. FIG. 16A is a longitudinal sectional perspective view, and FIG. 16B is a partially enlarged view of FIG.
As shown in FIG. 16, it was confirmed that nickel nanocylinders having a line width of about 50 nm and a height of about 500 nm were formed on the substrate.

(Example 13: Production of cobalt nanocylinder, magnetic evaluation)
A mold having a hole structure having a width of about 500 nm and a height of about 600 nm was formed on a silicon wafer substrate in the same manner as in Example 12. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, 2M aqueous sodium hydroxide solution was added to about 10 ml of a mixed aqueous solution containing a predetermined amount of cobalt sulfate heptahydrate, anhydrous trisodium citrate dihydrate, dimethylamine borane, ammonium sulfate, phosphoric acid and sodium tartrate dihydrate. An appropriate amount was added to adjust the solution pH to 9.0, and water was added to make the total amount of the solution 20 ml. The final concentration of each component is cobalt sulfate heptahydrate (0.1M), anhydrous trisodium citrate dihydrate (0.05M), dimethylamine borane (0.025M), ammonium sulfate (0.2M), phosphorus Acid (0.06M), sodium tartrate dihydrate (0.2M). The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a cobalt thin film on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 8 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, this substrate was subjected to an etching process using oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The cobalt nanocylinder which consists of a side part of a cobalt thin film was obtained by the above operation.

The cobalt nanocylinder was examined with a scanning electron microscope. FIG. 17 shows a scanning electron microscope image (longitudinal sectional perspective view) of the cobalt nanocylinder. As shown in FIG. 17, cobalt nanocylinders having a line width of about 30 nm and a height of about 500 nm were formed on the substrate.
Moreover, the magnetic measurement of this cobalt nanocylinder was performed with a superconducting magnetic flux quantum interferometer (SQUID). The result is shown in FIG. From the result, it was confirmed that the cobalt nanocylinder has ferromagnetism.

(Example 14: Production of cobalt nano-elliptical cylinder)
A mold having an elliptical hole structure having a major axis of about 4000 nm, a minor axis of about 600 nm, and a height of about 500 nm was formed on a silicon wafer substrate in the same manner as in Example 12 except that the mask pattern used was changed. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, 2M aqueous sodium hydroxide solution was added to about 10 ml of a mixed aqueous solution containing a predetermined amount of cobalt sulfate heptahydrate, anhydrous trisodium citrate dihydrate, dimethylamine borane, ammonium sulfate, phosphoric acid and sodium tartrate dihydrate. An appropriate amount was added to adjust the solution pH to 9.0, and water was added to make the total amount of the solution 20 ml. The final concentration of each component is cobalt sulfate heptahydrate (0.1M), anhydrous trisodium citrate dihydrate (0.05M), dimethylamine borane (0.025M), ammonium sulfate (0.2M), phosphorus Acid (0.06M), sodium tartrate dihydrate (0.2M). The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a cobalt thin film on the mold surface.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 8 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, this substrate was subjected to an etching process using oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. The cobalt nano ellipse ring which consists of the side part of a cobalt thin film was obtained by the above operation.

  The cobalt nanoelliptical cylinder was examined with a scanning electron microscope. FIG. 19 shows a scanning electron microscope image (longitudinal sectional perspective view) of the cobalt nanocylinder. As shown in FIG. 19, it was recognized that a cobalt nano-elliptical cylinder having a line width of about 30 nm and a height of about 400 nm was formed on the substrate.

(Example 15: Production of gold nano-elliptical cylinder)
On the silicon wafer substrate, an elliptical hole structure mold having a major axis of about 4000 nm, a minor axis of about 600 nm, and a height of about 500 nm was formed in the same manner as in Example 14. The substrate was subjected to oxygen plasma treatment (power 10 W, pressure 24 Pa, treatment time 3 seconds, treatment temperature 25 ° C.) to activate the surface of the mold.
Next, it was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.005M) and tin chloride (0.022M) for 2 minutes, then immersed in deionized water for 1 minute, and dried in a nitrogen gas stream. Next, the substrate was immersed in 30 ml of a mixed aqueous solution of hydrochloric acid (0.0005M) and palladium chloride (0.0015M) for 5 minutes, then immersed in deionized water for 1 minute, and the substrate was dried with a nitrogen gas stream.
Next, about 10 ml of a mixed aqueous solution containing nickel chloride (0.13 M), anhydrous trisodium citrate dihydrate (0.034 M), and dimethylamine borane (0.025 M) was prepared. The substrate was immersed in this solution (solution temperature 70 ° C., immersion time 20 seconds) to form a nickel thin film on the mold surface. Furthermore, this board | substrate was immersed in the gold substitution plating aqueous solution (Hitachi Kasei, brand name: HSG-500, water: HGS-500 = 9: 1) containing potassium cyanide metallide (0.024M) (solution temperature 70 degreeC). , Immersion time 8 minutes), gold displacement plating was performed to replace the nickel thin film on the mold surface with the gold thin film.
This electroless-plated substrate is subjected to an etching process using argon and CF ₄ mixed gas (argon flow rate 30 sccm, CF ₄ flow rate 5 sccm, pressure 2 pa, power 100 W, treatment time 3 minutes) using an RIE apparatus. The upper surface portion of the thin film was removed. Subsequently, it was immersed in an aqueous nitric acid solution (30 vol%) to remove nickel remaining without being replaced. Further, this substrate was etched with oxygen gas (pressure 24 Pa, power 10 W, treatment time 4 minutes), and the mold was removed. By the above operation, a gold nano-elliptical cylinder composed of the side surface portion of the gold thin film was obtained.

  The gold nanoelliptical cylinder was examined with a scanning electron microscope. FIG. 20 shows a scanning electron microscope image (longitudinal sectional perspective view) of the gold nanocylinder. As shown in FIG. 20, it was recognized that a gold nanoelliptical cylinder having a line width of about 30 nm and a height of about 400 nm was formed on the substrate.

It is the schematic which shows the 1st Embodiment of this invention. It is the schematic which shows the 2nd Embodiment of this invention. It is the scanning electron microscope image (a) of the structure obtained in Example 1, and its partial enlarged view (b). It is the scanning electron microscope image (a) of the structure obtained in Example 2, and its partial enlarged view (b). It is the scanning electron microscope image (a) of the structure obtained in Example 3, and its partial enlarged view (b). 6 is a scanning electron microscope image of the structure obtained in Example 4. FIG. 6 is a scanning electron microscope image of the structure obtained in Example 5. FIG. 7 is a scanning electron microscope image of the structure obtained in Example 6. FIG. It is the scanning electron microscope image (a) of the structure obtained in Example 7, and its partial enlarged view (b). 10 is a scanning electron microscope image of the structure obtained in Example 8. FIG. 12 is a graph showing the results of evaluating the conductivity of the structure obtained in Example 8. It is the scanning electron microscope image (a) of the structure obtained in Example 9, and its partial enlarged view (b). 10 is a scanning electron microscope image of the structure obtained in Example 10. FIG. 10 is a graph showing the magnetic evaluation results of the structure obtained in Example 10. It is the scanning electron microscope image (a) of the structure obtained in Example 11, and its partial enlarged view (b). It is the scanning electron microscope image (a) of the structure obtained in Example 12, and its partial enlarged view (b). 14 is a scanning electron microscope image of the structure obtained in Example 13. FIG. 10 is a graph showing the magnetic evaluation results of the structure obtained in Example 10. It is the scanning electron microscope image (a) of the structure obtained in Example 14, and its partial enlarged view (b). It is the scanning electron microscope image (a) of the structure obtained in Example 15, and its partial enlarged view (b).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Base material, 11 ... Mold, 21 ... Coating film, 22 ... 1st metal layer, 23 ... 2nd metal layer

Claims (15)

  At least a step of forming a coating film including a metal layer formed by electroless plating on the surface of the mold provided on the substrate, and leaving the part of or all of the coating film, the mold The structure is formed on the substrate by performing a step of removing a part or all of the structure.   The method of manufacturing a structure according to claim 1, wherein a step of removing a part of the coating film is performed before removing a part or all of the template.   The method of manufacturing a structure according to claim 1 or 2, wherein a step of removing a part of the coating film is performed after removing a part or all of the template.   The method of manufacturing a structure according to claim 3, wherein a step of removing a part of the coating film is performed after removing a part of the template.   The method for producing a structure according to any one of claims 2 to 4, wherein a part of the coating film to be removed is an upper end portion of the coating film.   By performing at least a step of forming a coating film including a metal layer formed by electroless plating on a surface of a mold provided on a substrate, and a step of removing a part of the coating film A method for producing a structure, comprising forming a structure on the substrate.   The method for manufacturing a structure according to claim 6, wherein a part of the coating film to be removed is an upper end portion of the coating film.   The method for producing a structure according to claim 6 or 7, wherein a step of removing a part or all of the template is performed before and / or after removing a part of the coating film.   The method for producing a structure according to any one of claims 1 to 8, wherein the electroless plating is performed after introducing a catalyst in the electroless plating on the surface of the mold.   The method for producing a structure according to any one of claims 1 to 9, wherein a hydrophilic treatment is performed on a surface of the mold before forming the metal layer.   The method for manufacturing a structure according to claim 10, wherein the hydrophilization treatment is an oxygen plasma treatment.   The method for producing a structure according to any one of claims 1 to 11, wherein the metal constituting the metal layer is at least one selected from the group consisting of gold, silver, copper, nickel, and cobalt.   The method for producing a structure according to any one of claims 1 to 12, wherein the template is made of a template-forming material containing an organic compound having a molecular weight of 500 or more.   The method for manufacturing a structure according to claim 13, wherein the template forming material is a resist composition.   The structure manufactured by the manufacturing method of the structure as described in any one of Claims 1-14.

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