JP2010214859A - Mold for nanoimprinting and manufacturing method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for nanoimprinting which enables forming of a highly precise and fine pattern for a resin for nanoimprinting, with a mold release layer having excellent releasability and durability and almost no adverse effect on uneven pattern dimensions, formed on the uneven pattern surface of the mold for nanoimprinting, as well as a method for manufacturing the mold for nanoimprinting. <P>SOLUTION: This mold for nanoimprinting 10 has an uneven pattern 12 which is formed on the surface of the substrate 11 and covered by the mold release layer 13. In addition, at least, the surface of the uneven pattern comprises a silicon oxide film and a metallic oxide film. The mold release layer 13 comprises a mold release agent, i.e. an amphiphatic silane coupling agent, and is formed of a monomolecular film with the hydrophobic group of the mold release agent orientated on the opposite side of the uneven pattern side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a nanoimprint mold in which a mold release process is performed on the surface of a concavo-convex pattern of a mold used for nanoimprint, and a method for producing the same.

  In recent years, especially for semiconductor devices, high-speed operation and low power consumption operation are required due to further progress in miniaturization, and high technology such as integration of functions called system LSIs is required. Under such circumstances, the lithography technology that is necessary for producing the pattern of the semiconductor device has become very expensive as the exposure apparatus and the like as the pattern becomes finer, and the price of the mask used therefor also becomes expensive. Yes.

  On the other hand, the nanoimprint method proposed by Chou et al. At Princeton University in 1995 is attracting attention as a fine pattern formation technology having a high resolution of about 10 nm, although the apparatus price and the materials used are low (non- (See Patent Document 1 and Patent Document 1).

  In the nanoimprint method, a fine pattern is formed by pressing a mold (also called a template, stamper, or mold) with a nanometer-size uneven pattern on the surface in advance against the resin that is formed on the surface of the workpiece. Is a technique for processing a workpiece using a resin with a pattern formed as a resist mask. Once the mold is made, the nanostructure can be easily and repeatedly molded, resulting in high throughput and economics, and because it is a nano-processing technology with little harmful waste, not only semiconductor devices in recent years, Application to various fields is expected.

  In such a nanoimprint method, a thermal nanoimprint method in which a concavo-convex pattern is transferred by heat using a thermoplastic resin, or a photo nanoimprint method in which a concavo-convex pattern is transferred by light using a photocurable resin (see, for example, Patent Document 2) ) Etc. are known.

  Molds used in the nanoimprint method are required to have pattern dimension stability, chemical resistance, processing characteristics, and the like. Taking the case of the optical nanoimprint method as an example, quartz glass is generally used. However, a mold made of quartz glass or the like has low releasability from the resin that is the pattern transfer material, and the resin adheres to the mold side when the mold is peeled off from the resin on which the transfer pattern is formed. There was a problem that the pattern accuracy was liable to be reduced. For this reason, as a method for improving the releasability, a method of applying and forming a thin film of a release agent such as a fluororesin on the surface of the concave / convex pattern of the mold has been proposed (for example, see Patent Document 3). Patent Document 3 describes a mold in which an organosilicon series monomolecular film (SAM; Self Assembled Monolayer) is formed as a release layer on a hard layer by vapor deposition or dipping.

JP-T-2004-504718 JP 2002-93748 A JP 2008-68612 A

S. Y. Chou et. al. , Science, vol. 272, p. 85-87, April, 1996.

However, as described in Patent Document 3 above, a conventional film formed by vapor deposition, dipping or spin coating of a silane coupling agent release agent is a molecular film even if it is a monomolecular film. The orientation was poor and the packing of the molecules was also scattered. Therefore, in the conventional film, the adhesive force and frictional force between the mold at the time of mold release and the applied nanoimprint resin are increased and the releasability is poor, and there is still a resin drawing defect formed on the surface of the workpiece. The problem of being easily generated has not been solved.
On the other hand, when an inorganic film is used as a release layer, it cannot be used for nano-level patterning because the thickness of the release layer increases and the pattern dimensions change significantly, and it deteriorates after imprinting. When the film is peeled off and then attached again, there is a problem that costs are increased.

  Therefore, the present invention has been made in view of the above problems. That is, the object of the present invention is to provide a highly accurate and fine resin for nanoimprinting, which has a release layer that has excellent releasability and durability and hardly affects the size of the unevenness pattern on the surface of the unevenness pattern of the nanoimprinting mold. It is providing the mold for nanoimprint which can form pattern of this, and its manufacturing method.

  In order to solve the above problems, a nanoimprint mold according to the invention of claim 1 is a nanoimprint mold having a concavo-convex pattern on a substrate surface, and the concavo-convex pattern is covered with a release layer. At least the surface is a silicon oxide film or a metal oxide film, and the release layer comprises a release agent of an amphiphilic silane coupling agent, and the hydrophobic group of the release agent is defined as the uneven pattern side. It is formed by a monomolecular film oriented on the opposite side.

  A nanoimprint mold according to the invention of claim 2 is the nanoimprint mold according to claim 1, wherein the release layer is formed by polymerizing and / or crosslinking the monomolecular film. It is what.

  A nanoimprint mold according to a third aspect of the present invention is the nanoimprint mold according to the second aspect, wherein the mold release agent has at least one polymerized functional group.

  The nanoimprint mold according to the invention of claim 4 is the nanoimprint mold according to claim 3, wherein the polymerizable functional group is vinyl group, epoxy group, diene group, diacetylene group, acrylic group, methacryl group, isocyanate. It is a functional group of any one of the groups.

  The nanoimprint mold according to the invention of claim 5 is the nanoimprint mold according to any one of claims 1 to 4, wherein the surface tension of the hydrophobic group of the release agent is 25 mN / m or less. It is characterized by being.

  A nanoimprint mold according to a sixth aspect of the present invention is the nanoimprint mold according to any one of the first to fifth aspects, wherein the hydrophobic group has fluorine.

  According to a seventh aspect of the present invention, there is provided a method for producing a mold for nanoimprinting, wherein a substrate surface has an uneven pattern, at least the surface of the uneven pattern is made of a silicon oxide film or a metal oxide film, and the uneven pattern is covered with a release layer. A method for producing a mold for nanoimprinting, comprising: developing a release agent of an amphiphilic silane coupling agent on a water surface to form a monomolecular film; and forming the hydrophobic group of the monomolecular film with the irregularities And a step of orienting it on the opposite side of the pattern side and transferring the monomolecular film onto the concave-convex pattern of the mold to form a release layer.

  The method for producing a nanoimprint mold according to the invention of claim 8 is the method for producing a nanoimprint mold according to claim 7, wherein the hydrophobic group of the monomolecular film is oriented on the side opposite to the concavo-convex pattern side, After the step of transferring the monomolecular film onto the concavo-convex pattern of the mold, the monomolecular film transferred onto the concavo-convex pattern is polymerized and / or cross-linked by heating, ultraviolet rays or ionizing radiation, and a release layer. The process of including is characterized by including.

  The method for producing a nanoimprint mold according to the invention of claim 9 is a method for producing a nanoimprint mold according to claim 7 or claim 8, wherein the mold release agent is spread on a water surface to form a monomolecular film. And the step of transferring the monomolecular film onto the concavo-convex pattern of the mold is characterized by the Langmuir-Blodget method.

  A method for producing a mold for nanoimprint according to the invention of claim 10 is characterized in that, in the method for producing a mold for nanoimprint according to claim 9, the Langmuir-Blodgett method is a horizontal adhesion method. .

  The method for producing a mold for nanoimprinting according to the invention of claim 11 is the method for producing a mold for nanoimprinting according to claim 10, wherein the horizontal adhesion method submerges the mold in advance under the water surface, After the agent is spread on the water surface to form a monomolecular film, the mold is gradually levitated to transfer the monomolecular film onto the concavo-convex pattern.

  According to the mold for nanoimprinting of the present invention, the mold release agent is densely formed with good orientation as a monomolecular film on the uneven pattern surface of the nanoimprinting mold to provide a mold release layer and durability. It is possible to obtain a nanoimprint mold capable of forming a fine resin pattern with high accuracy, which can reduce the pull-out defect of the nanoimprint resin applied and formed on the surface of the work material, with little effect on the uneven pattern dimensions. it can.

  According to the method for producing a mold for nanoimprinting of the present invention, an expensive large-scale facility is not required for forming a release layer, and the release layer is an organic monomolecular film. In this case, the release layer can be easily peeled off and regenerated as a release layer by re-forming the monomolecular film, which is advantageous in terms of cost.

It is a partial section schematic diagram showing an example of a mold for nanoimprinting of the present invention. It is a figure explaining the adhesion work of a mold and an imprint resist. It is a schematic diagram explaining the force which acts on the resist for imprint on a mold surface. It is a schematic diagram which shows an example of the state by which the monomolecular film of the mold release agent was formed on the uneven | corrugated pattern of synthetic quartz. It is a schematic diagram which shows one Embodiment of the mold for nanoimprint of this invention by LB method (vertical dipping method). It is a schematic diagram which shows one Embodiment of the mold for nanoimprint of this invention by LB method (horizontal adhesion method). It is a schematic diagram which shows other embodiment of the mold for nanoimprint of this invention by LB method (horizontal adhesion method).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Mold for nanoimprint)
FIG. 1 is a partial cross-sectional schematic view showing an example of a nanoimprint mold of the present invention. In FIG. 1, a nanoimprint mold 10 has a concavo-convex pattern 12 on one surface of a substrate 11, at least the surface of the concavo-convex pattern 12 is a silicon oxide film or a metal oxide film, and the concavo-convex pattern 12 is a release layer 13. The release layer 13 is made of a release agent of an amphiphilic silane coupling agent, and the hydrophobic group of the release agent is oriented on the imprint side opposite to the uneven pattern side. The monomolecular film is formed by polymerization and / or crosslinking.

  The substrate 11 is a member that holds the uneven pattern 12. In the present invention, the material constituting the substrate 11 is not particularly limited, and examples of the semiconductor material include silicon (Si), and examples of the metal material include aluminum (Al) and tungsten. (W), tantalum (Ta), copper (Cu), and the like. Furthermore, optically polished synthetic quartz glass, soda glass, fluorite, calcium fluoride and the like can be mentioned. The board | substrate 11 and the uneven | corrugated pattern 12 may be the same material, and what joined different material may be sufficient as it. Whichever material is used, in the present invention, in order to cause the surface of the concave / convex pattern 12 to react with the silane coupling agent, at least the surface of the concave / convex pattern 12 needs to be a silicon oxide film or a metal oxide film. Become. Synthetic quartz glass as a substrate material has been used as a photomask substrate and has a stable quality, and can have a light-transmitting structure in which the substrate 11 and the concavo-convex pattern 12 are integrated. This is more preferable because a concavo-convex pattern can be formed.

The release layer 13 in the present invention is composed of a release agent of an amphiphilic silane coupling agent. Specific examples of the hydrophilic group possessed by the silane coupling agent used in the present invention include, for example, Si—OCH ₃ , Si—OC ₂ H ₅ , Si—OH at a portion bonded to the substrate side in the molecule. And those having a functional group such as Si-OCl are preferred. When a highly hydrophilic functional group is at the end of the release agent molecule, the molecule is adsorbed to the substrate with the reactive end facing the substrate and the hydrophobic organic chain facing the outside. These functional groups are thought to adsorb by causing a chemical reaction with oxygen in the oxide film of the concavo-convex pattern of the substrate, as shown in the following formula (Formula 1). Since molecular adsorption requires a chemical reaction between the substrate and the terminal functional group, once the surface of the uneven pattern of the substrate is covered with organic molecules to form a monomolecular film, the molecular Adsorption does not occur. As a result, an organic monomolecular film in which molecules are closely gathered and aligned is formed. Examples of such a monomolecular film include a Langmuir Blodget film (LB film).

Examples of the hydrophobic group possessed by the amphiphilic silane coupling agent used in the present invention include an alkyl group represented by CH ₃ (CH ₂ ) _n — and fluoromethyl represented by CF ₃ (CF ₂ ) _n —. Group, epoxy group and the like (n = 0, 1,...).

  The film thickness of the release layer formed in the present invention is determined by the type of the monomolecular film, but is usually in the range of about 1 nm to 5 nm. Accordingly, it is possible to extremely reduce the influence on the uneven pattern size of the mold by forming the release layer. The film thickness can be measured with an atomic force microscope (AFM).

Here, the adhesiveness indicating the degree of release between the mold and the imprinting resin (hereinafter referred to as resist) will be described. FIG. 2 is an explanatory diagram for obtaining the adhesion work between the mold and the resist. The uneven pattern on the drawing is omitted. In FIG. 2, 21 indicates a mold, 22 indicates a resist, and 23 indicates air. As shown in FIG. 2A, the change in free energy required to separate the unit areas of the mold 21 and the resist 22, which are two contacting media, as shown in FIG. 2B is shown. The adhesion work W ₁₃₂ is expressed by the following formula (1) in consideration of the atmosphere.
W ₁₃₂ = W ₁₂ + W ₃₃ −W ₁₃ −W ₂₃ (1)
Here, W ₁₂ : work of adhesion between the mold and the resist interface, W ₃₃ : work of cohesion in the atmosphere, W ₁₃ : work of adhesion between the mold and the air interface, and W ₂₃ : work of adhesion between the resist and the air interface.

Also, in the atmosphere, if the interface energy between the mold and the atmosphere is γ _{mold / air} , the interface energy between the resist and the atmosphere is γ _{resist / air} , and the interface energy between the mold and the resist is γ _{mold / resist} , An adhesion work W ₁₃₂ (denoted as W _{mold / air / resist} ) for separating the _resist is expressed by the following formula (2).
W _{mold / air / resist} = γ _{mold / air} + γ _{resist / air} −γ _{mold / resist} … (2)

In vacuum, if the mold interface energy is γ _mold and the resist interface energy is γ _resist , the adhesion work W ₁₂ (W _{mold / resist} ) for separating the resist from the mold surface is expressed by the following equation (3). expressed.
W _{mold / resist} = γ _mold + γ _resist −γ _{mold / resist} (3)

On the other hand, the phenomenon between the imprinting resin (resist) and the solid surface of the mold is simply expressed by the degree of wetting of the resist on the solid surface. FIG. 3 is a schematic diagram for explaining the force acting on the resist on the mold surface. As shown in FIG. 3, when the resist 32 is formed on the surface of the mold 31, the wettability, i.e. hydrophilic, with respect to the contact angle representing the degree of hydrophobicity, the surface energy of the mold is the same reference numerals as in FIG. 2 gamma _mold When the interface energy between the mold and the resist is γ _{mold / resist} , the resist surface energy is γ _resist , and the contact angle is θ, the force relationship indicated by the three arrows is balanced, and the following Young-Dupre Equation (4) holds.
γ _mold = Γ _resist cosθ + γ _{mold / resist} (4)

From the above formulas (3) and (4), the adhesion work W _{mold / resist} is expressed by the following formula (5). Therefore, if γ _resist and θ are known, the adhesion work W _{mold / resist} for separating the resist from the mold surface can be obtained. γ _resist and θ can be obtained by measurement.
W _{mold / resist} = γ _resist (1 + cosθ) (5)

Therefore, in order to easily separate the resist from the mold surface, it is necessary to reduce the adhesion work W _{mold / resist} from Equation (5), that is, to use a material having a small _resist surface energy γ _resist (surface tension). (4) To reduce the surface energy γ _mold of the mold, for example, a release layer having a low surface energy may be provided on the mold surface. The surface tensions of typical solvents, resins and functional groups are known and are shown in Table 1.

  As a preferred embodiment of the present invention, in order to further increase the mechanical strength of the dense monomolecular film with uniform orientation transferred onto the concavo-convex pattern, a transfer agent having a polymerization functional group is used for transfer. The obtained monomolecular film of the release agent can be polymerized and / or crosslinked by heating, ultraviolet rays or ionizing radiation to form a release layer. The release agent used in the present embodiment preferably has at least one polymerization functional group, and the polymerizable functional group is a vinyl group, an epoxy group, a diene group, a diacetylene group, an acrylic group, a methacryl group, or an isocyanate group. Of these, a silane coupling agent having any functional group is preferred.

Examples of the silane coupling agent having a vinyl group include vinyltrimethoxysilane, vinyltriethoxysilane, vinyldimethoxysilane, and vinyltrichlorosilane. Examples of the silane coupling agent having a diene group include butadiene / trimethoxysilane. Examples of the silane coupling agent having an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycine. Examples thereof include sidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropyltriethoxysilane. Examples of the silane coupling agent having an acrylic group include 3-acryloxypropyltrimethoxysilane. Examples of the silane coupling agent having a methacryl group include γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, and the like. Is mentioned. The silane coupling agent having an isocyanate group, for example, include compounds represented by _{(OC 2 H 5) 3 Si} -CH 2 -C (NCO) H- (CH 2) 15 -CH 3. Examples of the silane coupling agent having a diacetylene group include compounds represented by CH ₃ — (CH ₂ ) ₈ —CC—CC— (CH ₂ ) ₅ —Si (OCH ₃ ) ₃ .

Furthermore, as described above, in the present invention, a release agent that reduces the surface energy of the release layer is preferable, and specifically, the surface tension of the hydrophobic group of the release agent is 25 mN / m or less. A release agent is preferred. This is because when the surface tension exceeds 25 mN / m, the releasability between the mold and the imprint resist decreases during imprinting. Furthermore, as shown in Table 1, the hydrophobic group of the release agent is more preferably a fluorine group. The fluorine group has a low surface tension, for example, the difluoromethyl group (—CF ₂ H) is 15 mN / m, and the trifluoromethyl group (—CF ₃ ) is 6 mN / m. FIG. 4 is a schematic diagram showing an example of a state in which a monomolecular film of a release agent having a fluoroalkyl group is formed on an uneven pattern of synthetic quartz.

As a release agent for an amphiphilic silane coupling agent having a fluorine group, a release agent having a fluoroalkyl group is preferable. For example, CF ₃ Si (OCH ₂ CH ₃ ) ₃ , CF ₃ (CF ₂ ) _{5 CH 2 CH 2 Si (OCH 2} CH 3) 3, CF 3 (CH 2) such as ₅ Si (OCH _{3) 3} can be exemplified.

  The above silane coupling agent is dissolved in a solvent such as a halogenated aliphatic solvent such as methylene chloride, chloroform, trifluoroethane, etc. to give a solution of a predetermined concentration, and is developed on the water surface as described later. A monomolecular film can be formed by the LB method.

  In the nanoimprint mold of the present invention, since the release layer is a monomolecular film, the release layer can be a uniform and dense layer, and the uneven pattern portion can be formed uniformly and with high definition. It becomes possible.

  Since the release layer of the present invention is formed of an organic monomolecular film, the release layer is peeled off from the mold by treating a film deteriorated after imprinting with a chemical solution containing an organic solvent or a chemical solution containing an alkali. It is easy to form a new monomolecular film again, and there is an advantage that the release layer can be re-created at a low cost.

(Manufacturing method of nanoimprint mold)
The method for producing a mold for nanoimprinting of the present invention has a concavo-convex pattern on one surface of a substrate, at least the surface of the concavo-convex pattern is made of a silicon oxide film or a metal oxide film, and the concavo-convex pattern is covered with a release layer. It is a method for producing a mold for nanoimprinting, a step of developing a release agent of an amphiphilic silane coupling agent on the water surface to form a monomolecular film, and the uneven pattern side of the hydrophobic group of the monomolecular film And a step of orienting it on the opposite side and transferring the monomolecular film onto the concavo-convex pattern of the mold to form a release layer.

  Furthermore, as a preferable embodiment of the present invention, after the step of transferring the monomolecular film onto the concave / convex pattern of the mold, the monomolecular film transferred onto the concave / convex pattern is polymerized and / or polymerized by heating, ultraviolet rays or ionizing radiation. A step of crosslinking to form a release layer.

  In the above manufacturing method, an embodiment of a step of developing a mold release agent on a water surface to form a monomolecular film and a step of transferring the monomolecular film onto an uneven pattern of a mold will be described.

  In the method for producing a mold for nanoimprinting according to the present invention, the step of developing the release agent on a water surface to form a monomolecular film, and the step of transferring the monomolecular film onto the uneven pattern of the mold include Langmuir This is based on the Blodgett method (hereinafter referred to as LB method).

(First embodiment)
In the case of the LB method, a vertical dipping method and a horizontal adhesion method are employed. This embodiment is a case by the vertical immersion method. First, a mold substrate having a concavo-convex pattern on one surface of the substrate and having at least the surface of the concavo-convex pattern made of a silicon oxide film or a metal oxide film is prepared.

  FIG. 5 is an example showing a method of forming the LB film by the vertical immersion method. As shown in FIG. 5 (a), a monomolecular film composed of a hydrophobic group 51 and a hydrophilic group 52 of organic molecules as release agents was formed on the water surface of the lower layer water 53, and a piston pressure 54 was applied to the water surface. In this state, when the substrate 55 having an oxide film on the surface of the concavo-convex pattern of the mold is immersed and pulled up perpendicularly to the liquid surface with the concavo-convex pattern side facing the monomolecular film side, the monomolecular film of the release agent is The hydrophilic group 52 surface is transferred to the substrate 55 side (FIG. 5B), and the hydrophobic group 51 of the monomolecular film of the release agent is opposite to the uneven pattern side on the uneven pattern surface of the mold. A monomolecular film oriented in the direction is formed (FIG. 5C).

  Next, the monomolecular film of the release agent transferred onto the concavo-convex pattern is polymerized and / or crosslinked by heating, ultraviolet rays or ionizing radiation to form a release layer. In the mold according to the manufacturing method of this embodiment, the hydrophobic group of the release agent monomolecular film is densely formed with good orientation on the outermost surface of the concavo-convex pattern, so that the releasability from the nanoimprint resist is good, and the concavo-convex pattern High-precision imprinting can be performed with almost no influence on the dimensions.

(Second Embodiment)
As shown in FIG. 6, the present embodiment is an example showing a method for forming an LB film by a horizontal deposition method. As in the first embodiment, a mold substrate having a concavo-convex pattern on one surface of the substrate and having at least the surface of the concavo-convex pattern made of a silicon oxide film or a metal oxide film is prepared.

  As shown in FIG. 6 (a), a piston pressure 64 is applied to a monomolecular film composed of a hydrophobic group 61 and a hydrophilic group 62 of an organic molecule formed on the water surface partitioned by the first partition 66, so that the hydrophobic group of the organic molecule A monomolecular film composed of 61 and a hydrophilic group 62 is formed on the water surface. Next, when the second partition 67 is moved to a portion opposite to the portion that contacts the first partition 66 of the substrate 65, and the mold substrate 65 is brought into horizontal contact with the monomolecular film from above (FIG. 6B), The monomolecular film in contact with the hydrophilic surface of the mold substrate 65 is inverted to attach the hydrophilic group 62 to the surface of the substrate 65 (FIG. 6C). Next, the substrate 65 is pulled up, and a mold substrate having a release layer formed of a monomolecular film in which the hydrophobic group 61 of the monomolecular film of the release agent is oriented on the opposite side of the uneven pattern side is formed on the uneven pattern surface. It is manufactured (FIG. 6D).

(Third embodiment)
FIG. 7 is an example of another embodiment showing a method of forming an LB film by the horizontal adhesion method. As in the first embodiment, a mold substrate having a concavo-convex pattern on one surface of the substrate and having at least the surface of the concavo-convex pattern made of a silicon oxide film or a metal oxide film is prepared.

  In the case of the horizontal adhesion method of the present embodiment, as shown in FIG. 7, the mold substrate 75 is previously submerged under the surface of the lower layer water 73, and then the water surface of the lower layer water 73 partitioned by the first partition wall 76. A piston pressure 74 is applied to the organic molecules of the release agent formed above to form a monomolecular film composed of hydrophobic groups 71 and hydrophilic groups 72 of the organic molecules on the water surface (FIG. 7A). Next, the substrate 75 is gradually levitated 78 and brought into horizontal contact with the monomolecular film to attach the hydrophilic group 72 to the substrate 75, and then opposite to the portion of the substrate 75 that contacts the first partition wall 76. The second partition wall 77 was moved to the portion (FIG. 7B), the substrate 75 was pulled up, and the hydrophobic group 71 of the monomolecular film of the release agent was oriented on the opposite side of the uneven pattern side on the uneven pattern surface. A mold substrate on which a monomolecular film is formed is produced (FIG. 7C). The horizontal adhesion method has the effect of avoiding deformation due to the flow of the monomolecular film.

  Next, the monomolecular film of the release agent transferred onto the concavo-convex pattern is polymerized and / or crosslinked by heating, ultraviolet rays or ionizing radiation to form a release layer. In the mold according to the manufacturing method of the present embodiment, the hydrophobic group of the release agent monomolecular film is densely formed with good orientation, good releasability, excellent print durability, and uneven pattern dimensions, as in the first embodiment. High-precision imprinting can be performed without substantially affecting the image quality.

  The LB method used in the production method of the present invention can obtain an organic thin film of molecular order, can control the molecular orientation and molecular arrangement, and can easily form a hetero film in which different molecules are arranged alternately. It has advantages such as being possible, and being able to form a film at room temperature and normal pressure.

  The LB film used in the present invention is not significantly different from the self-assembled monomolecular film (SAM) described in Patent Document 3 in terms of form if it is formed on a substrate. The formation method and the advanced two-dimensional molecular packing properties (high orientation and high order) resulting from the formation method have features that are not found in self-assembled monolayers. That is, the LB film-forming molecule is first developed on the gas-liquid interface, and the developed film is condensed by the trough to be changed into a monomolecular film as a highly packed condensed film. In the present invention, this highly oriented, highly ordered monomolecular film is transferred onto the substrate, and preferably, the monomolecular film transferred onto the concavo-convex pattern is polymerized and / or crosslinked by heating, ultraviolet rays or ionizing radiation. Thus, a strong release layer is obtained, and a mold for nanoimprinting having excellent release properties and durability is obtained.

Example 1
One surface of the optically polished synthetic quartz substrate was patterned to prepare an imprint mold substrate provided with concave and convex line & space patterns having a concave line pattern width of 40 nm, a depth of 40 nm, and a pitch of 80 nm. On the other hand, a methoxysilane compound (formula 2) having an epoxy group as a releasing agent for the silane coupling agent was dissolved in chloroform to obtain a 5 × 10 ⁻⁴ M / l solution. This was developed on the water surface, and a monomolecular film was formed on the mold substrate at a surface pressure of 40 mN / m by the LB method horizontal adhesion method shown in FIG. Next, the mold substrate on which the monomolecular film was formed was heat-dried on a hot plate at 80 ° C. for 5 minutes. Next, the entire surface of the monomolecular film on the mold substrate was irradiated with ultraviolet rays from a high-pressure mercury lamp, and the monomolecular film was polymerized / crosslinked to form a release layer.

  Imprinting is performed using a mold substrate provided with a release layer obtained by polymerizing / crosslinking a monomolecular film by the above-mentioned LB method, and a highly accurate and fine imprinting resin (resist) pattern is formed on the surface of the workpiece. As a result, it was possible to continuously form a pattern without a resist drawing defect.

(Comparative Example 1)
Similarly to Example 1, an imprint mold substrate provided with a line & space pattern by patterning one surface of a synthetic quartz substrate was prepared. Next, the same silane coupling agent methoxysilane compound chloroform solution as in Example 1 was used to form a self-assembled monolayer on the mold substrate.
When imprinting was performed using a mold substrate provided with the above self-assembled monomolecular film, a resist pull-out defect immediately occurred on the surface of the workpiece, and subsequent printing was impossible.

10 Nanoimprint mold 11 Substrate 12 Concavity and convexity pattern 13 Release layer 21, 31 Mold 22, 32 Resist 23 Air 51, 61, 71 Hydrophobic groups 52, 62, 72 Hydrophilic groups 53, 63, 73 Lower layer water 54, 64, 74 Piston Pressure 55, 65, 75 Mold substrate 66, 76 First partition 67, 77 Second partition 78 Levitation

Claims (11)

In the mold for nanoimprint having a concavo-convex pattern on the substrate surface, and the concavo-convex pattern is covered with a release layer,
At least the surface of the concavo-convex pattern is a silicon oxide film or a metal oxide film,
The release layer is composed of a release agent of an amphiphilic silane coupling agent, and is formed of a monomolecular film in which the hydrophobic group of the release agent is oriented on the side opposite to the uneven pattern side. A mold for nanoimprinting, characterized by being.   The mold for nanoimprinting according to claim 1, wherein the release layer is formed by polymerizing and / or crosslinking the monomolecular film.   The mold for nanoimprint according to claim 2, wherein the release agent has at least one or more polymerization functional groups.   4. The nanoimprint according to claim 3, wherein the polymerizable functional group is any one of a vinyl group, an epoxy group, a diene group, a diacetylene group, an acrylic group, a methacryl group, and an isocyanate group. Mold.   The nanoimprint mold according to any one of claims 1 to 4, wherein the surface tension of the hydrophobic group of the release agent is 25 mN / m or less.   The mold for nanoimprinting according to any one of claims 1 to 5, wherein the hydrophobic group has fluorine. A method for producing a mold for nanoimprinting having a concavo-convex pattern on a substrate surface, wherein at least the surface of the concavo-convex pattern is made of a silicon oxide film or a metal oxide film, and the concavo-convex pattern is covered with a release layer,
Developing a release agent of an amphiphilic silane coupling agent on the water surface to form a monomolecular film;
Orienting the hydrophobic group of the monomolecular film on the side opposite to the concave / convex pattern side, transferring the monomolecular film onto the concave / convex pattern of the mold, and forming a release layer;
A method for producing a mold for nanoimprinting, comprising: After the step of orienting the hydrophobic group of the monomolecular film on the side opposite to the concave / convex pattern side and transferring the monomolecular film onto the concave / convex pattern of the mold,
A step of polymerizing and / or crosslinking the monomolecular film transferred onto the concavo-convex pattern with heating, ultraviolet rays or ionizing radiation to form a release layer;
The manufacturing method of the mold for nanoimprints of Claim 7 characterized by the above-mentioned.   The step of developing the mold release agent on a water surface to form a monomolecular film and the step of transferring the monomolecular film onto an uneven pattern of the mold are performed by a Langmuir Blodget method. A method for producing a mold for nanoimprinting according to claim 7 or 8.   The method for producing a mold for nanoimprinting according to claim 9, wherein the Langmuir Blodgett method is a horizontal adhesion method.   In the horizontal adhesion method, the mold is submerged in advance under the water surface, and the mold release agent is spread on the water surface to form a monomolecular film, and then the mold is gradually levitated to form the monomolecular film. The method for producing a mold for nanoimprint according to claim 10, wherein the method is a method of transferring onto a concavo-convex pattern.

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