CN111752093A

CN111752093A - Method for forming semiconductor structure

Info

Publication number: CN111752093A
Application number: CN202010221722.5A
Authority: CN
Inventors: 翁明晖; 訾安仁; 张庆裕; 林进祥; 刘朕与
Original assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Current assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Priority date: 2019-03-28
Filing date: 2020-03-26
Publication date: 2020-10-09
Anticipated expiration: 2040-03-26
Also published as: CN111752093B; TW202036160A; TWI743720B

Abstract

A method for forming a semiconductor device structure is provided herein. The method includes forming a material layer on a substrate and forming a photoresist layer on the material layer. The photoresist layer includes an inorganic material and an adjuvant. The inorganic material includes a plurality of metal cores and a plurality of first linking groups, and the first linking groups are bonded to the metal cores. The method includes exposing a portion of the photoresist layer. The photoresist layer includes an exposed region and an unexposed region. In the exposed areas, the adjuvant reacts with the first linking group. The method includes removing unexposed regions of the photoresist layer using a developer to form a patterned photoresist layer. The developer includes a ketone-based solvent having formula (a), or an ester-based solvent having formula (b).

Description

Method for forming semiconductor structure

Technical Field

The present invention relates to a memory device, and more particularly, to a nonvolatile memory device and a method of manufacturing the same.

Background

Semiconductor devices are used in various electronic applications such as personal computers, mobile phones, digital cameras, and other electronic devices. Semiconductor devices are typically fabricated by sequentially depositing layers of insulating or dielectric, conductive, and semiconductive materials on a semiconductor substrate, and patterning the layers using a photolithographic process to form circuit elements and devices on the semiconductor substrate. Many integrated circuits are typically fabricated on a single semiconductor wafer, and individual dies are singulated by cutting between the integrated circuits along dicing lines. The individual dies are typically packaged separately, for example, in a multi-chip module, or other type of package.

However, these advances have increased the complexity of integrated circuits in processing and fabrication. As feature sizes continue to shrink, processes continue to become more difficult to perform. Therefore, it has become a challenge to form reliable semiconductor devices in smaller and smaller sizes.

Disclosure of Invention

An embodiment of the invention discloses a method for forming a semiconductor structure, which includes: forming a material layer on the substrate; forming a photoresist layer over the material layer, wherein the photoresist layer comprises an inorganic material and an adjuvant, wherein the inorganic material comprises a plurality of metal cores and a plurality of first linking groups, and wherein the first linking groups are bonded to the metal cores; exposing a portion of a photoresist layer, wherein the photoresist layer includes an exposed region and an unexposed region, and in the exposed regionThe adjuvant reacts with the first linking group; and removing the unexposed regions of the photoresist layer using a developer to form a patterned photoresist layer, wherein the developer comprises a ketone-based solvent, an ester-based solvent, or a combination thereof, wherein the ketone-based solvent has a substituted or unsubstituted C₆-C₇The cyclic ketone, ester-based solvent has formula (b):

wherein R is₃Is straight-chain or branched C₁-C₅Alkyl, or straight or branched C₂Alkoxy radical, and R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₃-C₆An alkoxy group.

An embodiment of the invention discloses a method for forming a semiconductor structure, which includes: forming a material layer on the substrate; forming a bottom layer on the material layer; forming a middle layer on the bottom layer; forming a photoresist layer over the intermediate layer, wherein the photoresist layer comprises an inorganic material having a plurality of metal cores and a plurality of first linking groups, wherein the first linking groups are bonded to the metal cores; forming a modification layer below or above the photoresist layer, wherein the modification layer comprises an auxiliary agent; performing an exposure process to expose a portion of the photoresist layer, wherein the adjuvant reacts with the first linking group during the exposure process; and developing the photoresist layer using a ketone-based solvent or an ester-based solvent to form a patterned photoresist layer, wherein the ketone-based solvent has a substituted or unsubstituted C₆-C₇The cyclic ketone, ester-based solvent has formula (b):

An embodiment of the invention discloses a method for forming a semiconductor structure, which includes: forming a material layer on the substrate; forming a bottom layer on the material layer; forming a middle layer on the bottom layer; forming a photoresist layer over the intermediate layer, wherein the photoresist layer comprises an inorganic material and an adjuvant, wherein the inorganic material comprises a plurality of first linking groups bonded to the plurality of metal cores, and the adjuvant comprises a plurality of second linking groups; performing an exposure process to expose a portion of the photoresist layer, wherein the second linking group reacts with the first linking group during the exposure process; removing a portion of the photoresist layer using an ester-based solvent to form a patterned photoresist layer, wherein the ester-based solvent has formula (b):

wherein R is₃Is straight-chain or branched C₁-C₅Alkyl, or straight or branched C₂Alkoxy radical, and R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₃-C₆An alkoxy group; removing a portion of the intermediate layer using the patterned photoresist layer as a mask to form a patterned intermediate layer; and removing a portion of the bottom layer using the patterned intermediate layer as a mask to form a patterned bottom layer.

Drawings

The disclosure is fully disclosed in the following detailed description in conjunction with the accompanying drawings. It should be noted that the drawings are not necessarily drawn to scale in accordance with common practice in the industry. In fact, the dimensions of the elements may be arbitrarily increased or reduced for clarity of illustration.

Fig. 1A-1D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Fig. 2A-2C are schematic cross-sectional views of stages in the formation of a semiconductor structure, according to some embodiments of the present invention.

Fig. 3A is a schematic diagram of the chemical structure of a photoresist layer before an exposure process is performed, in accordance with some embodiments.

Fig. 3B is a schematic diagram of the chemical structure of a photoresist layer after an exposure process is performed, in accordance with some embodiments.

Fig. 4A-4D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Fig. 5A-5E are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Fig. 6A-6G are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Figures 7A-7F are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Figures 8A-8D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention.

Wherein the reference numerals are as follows:

10 mask

12 inorganic material

14 adjuvant

16A compound

102 substrate

104 material layer

104a patterned material layer

105 doped region

106 bottom layer

106a patterned underlayer

108 intermediate layer

108a patterned intermediate layer

109 decorative layer

109a patterned modification layer

110 photoresist layer

110a patterned photoresist layer

120: three layer photoresist layer

122 metal core

124 first linking group

172 exposure process

174 ion implantation process

180 developing process

182 cleaning process

L₁A first linking group

L₂A second linking group

L₃A third linking group

P1 first spacing

T₁A first thickness

T₂The second thickness

Detailed Description

The following disclosure provides many different embodiments or examples for implementing different features (features) of the present disclosure. The following disclosure describes specific examples of components and arrangements thereof to simplify the description. Of course, these specific examples are not intended to be limiting. For example, if the specification states a first element formed on or above a second element, that is, embodiments that may include the first element in direct contact with the second element, embodiments may include additional elements formed between the first and second elements, such that the first and second elements may not be in direct contact. In addition, the same reference numbers and/or designations may be reused for the different examples disclosed below. These iterations are for simplicity and clarity and are not intended to limit the particular relationship between the various embodiments and/or configurations discussed.

Various variations of the embodiments are described below. Like element numerals are used to identify like elements throughout the various views and depicted embodiments. It should be understood that additional operational steps may be provided before, during, or after the method described, and that in other embodiments of the method described, some of the steps described may be replaced or omitted.

The advanced photolithography processes, methods, and materials described in embodiments of the present invention may be used in a variety of applications, including fin-type field effect transistors (finfets). For example, the fins may be patterned by the methods described in the embodiments to provide a tighter pitch between features, and the methods described herein may be well suited for use herein. In addition, the spacers used to form the fins of the finfet may also be processed as described in the examples.

Embodiments of semiconductor structures and methods of forming the same are provided below. Fig. 1A-1D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The method may be used in a number of applications, such as fin field effect transistor (FinFET) device structures.

Referring to fig. 1A, a substrate 102 is provided. The substrate 102 may be made of silicon or other semiconductor material. In some embodiments, the substrate 102 is a wafer. Alternatively or additionally, the substrate 102 may comprise other elemental semiconductor materials, such as germanium (Ge). In some embodiments, the substrate 102 is made of a compound semiconductor or an alloy semiconductor, for example, silicon carbide, gallium arsenide, indium arsenide, or indium phosphide, silicon germanium carbide, gallium arsenide phosphide, or gallium indium phosphide. In some embodiments, substrate 102 comprises an epitaxial layer. For example, the substrate 102 has an epitaxial layer on a bulk semiconductor (bulk) substrate.

Some device components may be formed on the substrate 102. Such device elements include transistors (e.g., Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), Complementary Metal Oxide Semiconductor (CMOS) transistors, Bipolar Junction Transistors (BJTs), high-voltage transistors (high-voltage transistors), high-frequency transistors (high-frequency transistors), p-channel and/or n-channel field effect transistors (PFETs/NFETs), etc.), diodes, and other suitable elements. Various processes may be performed to form device components, such as deposition, etching, implantation, photolithography, annealing, and/or other suitable processes.

The substrate 102 may include various doped regions, such as p-type wells or n-type wells. P-type dopants (e.g., boron or boron difluoride (BF)) can be used₂) And/or n-type dopants (e.g., phosphorus or arsenic) to dope the doped regions. In some other embodiments, the doped regions may be formed directly on the substrate 102.

The substrate 102 also includes isolation structures (not shown). The isolation structures are used to define and electrically isolate various devices formed in the substrate 102 and/or on the substrate 102. In some embodiments, the isolation structure includes a Shallow Trench Isolation (STI) structure, a local oxidation of silicon (LOCOS) structure, or other suitable isolation structure. In some embodiments, the isolation structure comprises silicon oxide, silicon nitride, silicon oxynitride, fluorine-doped silicate glass (FSG), or other suitable material.

Thereafter, according to some embodiments of the present invention, a material layer 104 is formed on the substrate 102, and a photoresist layer 110 is formed on the material layer 104. In some embodiments, the photoresist layer 110 includes an inorganic material 12, an adjuvant (adjuvant) 14, and a solvent. The inorganic material 12 and adjuvant 14 are uniformly distributed in the solvent. The structures of the inorganic material 12 and the adjuvant 14 will be described in detail below. In some embodiments, the material layer 104 or the photoresist layer 110 are each independently formed via a deposition process, which may include, for example, a spin-on coating (spin-on) process, a Chemical Vapor Deposition (CVD) process, a Physical Vapor Deposition (PVD) process, and/or other suitable deposition processes.

Next, as illustrated in fig. 1B, according to some embodiments of the invention, a mask 10 is formed on the photoresist layer 110, and an exposure process 172 is performed on the photoresist layer 110 to form an exposed region and an unexposed region.

The radiant energy of the exposure process 172 may include 248nm generated by krypton fluoride (KrF) excimer laser (eximer laser)A beam of light, a 193nm beam of light generated by an argon fluoride (ArF) excimer laser, a beam of light generated by fluorine (F)₂) An excimer laser produces a 157nm beam, or extreme ultra-violet (EUV) light, for example, having a wavelength of about 13.5 nm.

After the exposure process 172, a post-exposure-baking (PEB) process is performed. In some embodiments, the post-exposure bake process comprises a heating process using microwave or infrared lamps. In some embodiments, the post-exposure bake process is performed at a temperature range of about 70 ℃ to about 250 ℃. In some other embodiments, the post-exposure bake process is performed for a duration in a range from about 20 seconds to about 240 seconds. It should be noted that, since the microwave or infrared lamp heating process can uniformly supply heat, the photoresist layer 110 can be uniformly baked at a specific temperature by using the microwave or infrared lamp heating process. By providing heat uniformly, the chemical reaction in the photoresist layer 110 can be made to react quickly. Thus, the heating time of the baking process can be reduced to less than 30 seconds.

Fig. 3A is a schematic diagram of the chemical structure of a photoresist layer prior to performing an exposure process 172 according to some embodiments.

In some embodiments, the photoresist layer 110 includes an inorganic material 12, an adjuvant 14, and a solvent. The inorganic material 12 and adjuvant 14 are uniformly distributed in the solvent. The inorganic material 12 includes a plurality of metal cores 122 and a plurality of first linking groups (L)₁)124, wherein the first linking group (L)₁)124 are bonded to the metal core 122. In some embodiments, the first linking group (L)₁)124 are chemically bonded to the metal core 122. The chemical bond of the chemical bond may be a single bond or a conjugated bond. Adjuvant 14 may include a Photo Acid Generator (PAG), a quencher (Q), a cross-linker, a photobase generator (PBG), or a combination thereof. In some embodiments, the weight proportion of adjuvant 14 relative to solvent is in the range of about 0.1 wt% to about 10 wt%. If the weight ratio of the adjuvant 14 with respect to the solvent is less than 0.1 wt%, it may not increase the cross-linking between the inorganic material 12 and the adjuvant 14The reaction rate of the coupling reaction. If the weight proportion of adjuvant 14 relative to the solvent is greater than 10 wt.%, other undesirable chemical reactions may occur. For example, if the amount of adjuvant 14 is too large, the melting point of the inorganic material 12 may decrease. Once the melting point of the inorganic material 12 is lowered, the heat resistance of the inorganic material 12 to the baking temperature will be lowered and the performance of the photoresist layer 110 will be deteriorated.

In some embodiments, the metal core 112 is formed from a metal, such as tin (Sn), indium (In), antimony (Sb), or other suitable material. In some embodiments, the first linking group 124 comprises an aliphatic or aromatic group, unbranched or branched, cyclic or acyclic, saturated with hydrogen or oxygen or halogen and having 1-9 carbons (C)₁-C₉) E.g., alkyl, olefin, benzene. In some embodiments, the first linking group 124 is configured to provide radiation sensitivity (radiosensitivity). In some embodiments, the first linking group 124 has one hydroxyl (-OH) group and the second linking group L₂Has one hydroxyl group (-OH), and the two hydroxyl groups react with each other to undergo hydrolysis. In some other embodiments, the first linking group (L)₁)124 have a carbon-carbon double bond (alkene) or a carbon-carbon triple bond (alkyne), and a second linking group L₂With a first linking group (L)₁)124 to perform an addition reaction (addition reaction). In some other embodiments, the first linking group (L)₁)124 has a carbonyl group (C ═ O) or an imino group (C ═ N), and the second linking group L2 is linked to the first linking group (L)₁)124 to perform an addition reaction.

In some embodiments, the adjuvant 14 includes a second linking group L₂And a third linking group L₃Wherein the second linking group L₂And a third linking group L₃May react with the first linking group 124 on the metal core 122. With the aid of the adjuvant 14, one of the metal cores 122 bonds to the other metal core 122 to form the compound 16, and the compound 16 has a size larger than that of each of the metal cores 122.

In some particular embodiments, the solvent includes Propylene Glycol Methyl Ether Acetate (PGMEA), Propylene Glycol Monomethyl Ether (PGME), 1-ethoxy-2-propanol (1-ethoxy-2-propanol, PGEE), gamma-butyrolactone (GBL), Cyclohexanone (CHN), Ethyl Lactate (EL), methanol, ethanol, propanol, n-butanol, acetone, Dimethylformamide (DMF), Isopropanol (IPA), Tetrahydrofuran (THF), methyl isobutyl carbinol (MIBC), n-butyl acetate (n-butyl acetate, ba), 2-heptanone (2-heptanone, MAK), or a combination thereof.

In some embodiments, the photoacid generator (PAG) comprises a cation and an anion. In some embodiments, the cation comprises formula (I) or (II). In some embodiments, the anion comprises formula (III), (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI), or (XII).

In some embodiments, the quencher (Q) comprises formula (XIII), (XIV), (XV), (XVI), (XVII), (XVIII), (XIX), (XX), or (XXI).

In some embodiments, the crosslinker comprises formula (XXII), (XXIII), (XXIV), (XXV), (XXVI), (XXVII), (XXVIII), (XXIX) or (XXX).

In some embodiments, the photobase generator (PBG) comprises formula (XXXI), (XXXII), (XXXIII), (XXXIV), (XXXV), (XXXVI), (XXXVII), (XXXVIII), or (XXXIX), (XL), (XLI), or (XLII).

Fig. 3B is a schematic diagram of the chemical structure of the photoresist layer after performing an exposure process 172 according to some embodiments. It is noted that the adjuvant 14 serves to assist the crosslinking reaction between adjacent metal cores 122 after the exposure process 172. More specifically, the second linking group L of the adjuvant 14₂And a third linking group L₃Reacts with the first linking group 124 on the metal core 122, thereby forming a chemical bond between the inorganic material 12 and the adjuvant 14. The chemical bond of the chemical bond may be a single bond or a conjugated bond. More specifically, the chemical bond is formed at the second linking group L of the adjuvant 14₂With a first linking group (L)₁)124 and a third linking group L formed in the adjuvant 14₃With a first linking group (L)₁) 124.

During the exposure process 172, adjacent first linking groups L bonded to different metal cores 122₁Can react with each other by performing a crosslinking reaction. Having a metal core 122 and a first linking group (L)₁) The inorganic material 12 of 124 is used to enhance the radiation absorption of the exposure process 172. For example, inorganic materials based on indium (In based) or tin (Sn based) have good absorption for far ultraviolet light with a wavelength of 193nm and extreme ultraviolet light with a wavelength of 13.5 nm. Before the exposure process 172 is performed, there is one between adjacent first bonding agents L1Distance. In order to increase the reaction rate of the crosslinking reaction, an adjuvant 14 is added to the photoresist layer 110. The auxiliary agent 14 can shorten the distance between the adjacent metal cores 122, and therefore, the second linking group L at the auxiliary agent 14₂And a third linking group L₃With the aid of (a) one of the first linking groups (L) located on the first metal core 122₁)124 can be linked to one of the first linking groups (L) located on the second metal core 122₁) 124. It is noted that the crosslinking reaction between adjacent metal cores 122 is improved by the addition of the adjuvant 14.

In a comparative example, the photoresist layer 110 includes the inorganic material 12 and a solvent, but does not include the adjuvant 14 described above. In this comparative example, the crosslinking reaction between the adjacent metal cores 122 has a first reaction rate. In some embodiments, the photoresist layer 110 includes the inorganic material 12 and the adjuvant 14, and the solvent. The crosslinking reaction between adjacent metal cores 122 has a second reaction rate. One of the metal cores 122 is bonded to the other metal core 122 by the addition of the adjuvant 14. The reaction rate of the crosslinking reaction between the adjacent metal cores 122 is increased with the aid of the adjuvant 14. The second reaction rate is greater than the first reaction rate with the aid of the adjuvant 14.

Next, as shown in fig. 1C, the photoresist layer 110 is developed by performing a developing process 180 to form a patterned photoresist layer 110a according to some embodiments of the invention. Compound 16 is formed in photoresist layer 110. Compound 16 is formed by reacting inorganic material 12 with adjuvant 14. A portion of the metal core 122 reacts with the adjuvant 14, but another portion of the metal core 122 remains in the photoresist layer 110. In other words, compound 16 is linked through the first linking group L₁A second linking group L₂And a third linking group L₃And is formed of an inorganic material 12 and an adjuvant 14.

There are two types of development processes: a Positive Tone Definition (PTD) process and a Negative Tone Definition (NTD) process. The positive tone development process uses a positive tone developer (positive tone developer), which generally refers to a developer that selectively dissolves and removes exposed portions of a photoresist layer. The negative tone development process uses a negative tone developer (negative tone developer), which generally refers to a developer that selectively dissolves and removes unexposed portions of the photoresist layer 110. In some embodiments, the Positive Tone Development (PTD) developer is an aqueous base developer, such as, for example, tetra alkyl ammonium hydroxide (TMAH).

The developing process 180 is performed by using a developer. The developer has high hydrophobicity and low dipole momentum (dipole momentum). In some embodiments, the dipole momentum of the developer used in the development process 180 is in the range of about 0.8 debye to about 4 debye. If the dipole momentum is less than 0.8 debye, the solubility of the unexposed portions of the photoresist layer 110 may be too low and may not completely remove unwanted photoresist residues in the unexposed portions (the unexposed portions should be completely removed). If the dipole momentum is greater than 4 debye, the solubility of the exposed portions of the photoresist layer 110 may be too high, the exposed portions of the photoresist layer 110 may be over developed (the exposed portions should remain), and the shape of the exposed portions may crack or neck.

In some embodiments, the Negative Tone Development (NTD) process developer comprises a ketone-based solvent, an ester-based solvent, or a combination thereof. In some embodiments, the negative tone development process developer includes a ketone-based solvent, and the ketone-based solvent has a total number of carbon atoms in a range of 5 to 15. In some embodiments, the ketone-based solvent has formula (a):

wherein R is₁Is straight-chain or branched C₁-C₅Alkyl radical, and R₂Is straight-chain or branched C₃-C₉An alkyl group.

In some embodiments, the ketone-based solvent does not include 2-heptanone. In some embodiments, the ketone-based solvent is not 2-heptanone.

Tables 1 through 9 show some examples of ketone-based developers according to some embodiments of the present invention. As shown in Table 1, the ketone-based solvent has the formula (a) wherein R₁Is CH₃，R₂Is straight-chain or branched C₄-C₉An alkyl group. In some embodiments, the ketone-based solvent has formula (a), wherein R is₁Is CH₃，R₂Is branched C₅An alkyl group. For example, the ketone-based solvent is 5-methyl-2-hexanone. In some embodiments, the ketone-based solvent has formula (a), wherein R is₁Is CH₃，R₂Is straight chain C₆An alkyl group. For example, the ketone-based solvent is 2-octanone.

TABLE 1

As shown in Table 2, the ketone-based solvent has formula (a) wherein R₁Is C₂H₅，R₂Is straight-chain or branched C₄-C₈An alkyl group. In some embodiments, the ketone-based solvent has formula (a), wherein R is₁Is C₂H₅，R₂Is straight chain C₄An alkyl group. For example, the ketone-based solvent is 3-heptanone.

TABLE 2

As shown in Table 3, the ketone-based solvent has formula (a) wherein R₁Is straight chain C₃H₇，R₂Is straight-chain or branched C₃-C₇An alkyl group.

TABLE 3

As shown in Table 4, the ketone-based solvent has formula (a) wherein R₁Is branched C₃H₇，R₂Is straight chain C₄-C₆An alkyl group.

TABLE 4

As shown in Table 5, the ketone-based solvent has formula (a) wherein R₁Is branched C₄H₉，R₂Is branched C₄-C₆An alkyl group.

TABLE 5

As shown in Table 6, the ketone-based solvent has formula (a) wherein R₁Is branched C₅H₁₁，R₂Is straight chain C₄-C₅An alkyl group.

TABLE 6

As shown in Table 7, the ketone-based solvent has formula (a) wherein R₁Is branched C₃H₇，R₂Is C₃H₇。

TABLE 7

As shown in Table 8, the ketone-based solvent has formula (a) wherein R₁Is CH₃Or C₃H₇，R₂Is straight-chain or branched C₃-C₅An alkyl group.

TABLE 8

In some embodiments, the ketone-based solvent is a substituted or unsubstituted C₆-C₇Cyclic ketones wherein the substituents are hydrogen, alkyl. More specifically, as shown in table 9, in some embodiments, the cyclic ketone has at least one hydrogen atom substituted with C₁-C₃Alkyl substitution, e.g. methyl (-CH)₃) Ethyl (-C)_2H5) Isopropyl (-C)₃H₇) Or n-propyl (-C)₃H₇)。

TABLE 9

In some embodiments, the developer includes an ester-based solvent, and the ester-based solvent has a total number of carbon atoms in a range from 5 to 14. In some embodiments, the ester-based solvent has formula (b):

Tables 10-15 show some examples of ester-based solvents, according to some examples of the present invention. As shown in Table 10, the ester-based solvent has the formula (b) wherein R₃Is CH₃，R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₂-C₆An alkoxy group.

Watch 10

As shown in Table 11, the ester-based solvent has formula (b), wherein R₃Is C₂H₅，R₄Is straight-chain or branched C₄An alkyl group.

TABLE 11

As shown in Table 12, the ester-based solvent has formula (b), wherein R₃Is C₃H₇，R₄Is straight-chain or branched C₃-C₄An alkyl group.

TABLE 12

As shown in Table 13, the ester-based solvent has formula (b), wherein R₃Is C₄H₉，R₄Is straight-chain or branched C₂-C₄An alkyl group.

Watch 13

As shown in Table 14, the ester-based solvent has formula (b), wherein R₃Is C₅H₁₀，R₄Is straight chain C₂An alkyl group.

TABLE 14

As shown in Table 15, the ester-based solvent has formula (b), wherein R₃Is C₂H₅O，R₄Is straight-chain or branched C₂-C₃An alkyl group.

Watch 15

As illustrated in fig. 1C, in some embodiments, a negative tone development process is performed, leaving exposed regions of the photoresist layer 110, and unexposed regions of the photoresist layer 110 are removed by a ketone-based solvent. After the exposure process 172 is performed, the exposed regions of the photoresist layer 110 become more hydrophilic, and thus, the unexposed regions of the photoresist layer 110 are removed using a ketone-based solvent. Furthermore, compound 16 has a larger average molecular weight than inorganic materials, and thus compound 16 cannot be easily dissolved in an organic solvent. Thus, exposed regions of the photoresist layer 110 may remain while unexposed regions of the photoresist layer 110 are removed.

The Critical Dimension (CD) of the patterned photoresist layer 110a is determined by the radiation energy of the exposure process and the developer of the development process. The radiation dose is used to induce a crosslinking reaction between the inorganic material 12 and the adjuvant 14. High radiation doses will cause a high degree of crosslinking reaction. Therefore, the radiation dose should be increased to obtain a larger critical dimension of the patterned photoresist layer 110 a. However, higher radiation doses may result in higher costs. In order to reduce the cost of the exposure process, the unexposed regions of the photoresist layer 110 of the embodiments of the present invention are removed by using a more hydrophobic ketone-based solvent. Compound 16 in the exposed areas becomes hydrophilic and is not easily removed by the hydrophobic ketone-based solvent. Thus, the critical dimension of the exposed region of the photoresist layer 110 may be increased by using a hydrophobic ketone-based solvent.

In one comparative example, the ketone solvent is 2-heptanone. The ketone-based solvents as described in tables 1 to 9 of the present invention were higher in hydrophobicity compared to 2-heptanone of this comparative example. Thus, the exposed regions of the photoresist layer 110 are not removed by using a hydrophobic ketone-based solvent. Embodiments of the present invention provide a simple method to obtain larger critical dimensions of the patterned photoresist layer 110a without increasing the radiation dose of the exposure process. In some embodiments, the radiation dose is reduced by about 5% to about 10%.

In some embodiments, the developer further comprises water, and the proportion of water relative to the developer is in the range of about 0.01 wt% to about 3 wt%. Water is used as a catalyst during the crosslinking reaction between the inorganic material 12 and the adjuvant 14. If the crosslinking reaction does not proceed to completion during the exposure process, water added in the developer during the development process may contribute to the crosslinking reaction. Note that the amount of water is not so large that the polarity of the developer is not significantly affected by water.

In some embodiments, the developer further comprises a surfactant. The surfactant is to increase solubility and reduce surface tension on the material layer 104. In some embodiments, the ratio of surfactant to developer is in the range of about 0.01 wt% to about 1 wt%. In some embodiments, the surfactant comprises formula (b), formula (c), formula (d), formula (e), formula (f), or formula (g) below, n represents an integer. In the formulae (b), (C), (d) and (e), R is hydrogen or straight chain C₁-C₂₀An alkyl group. In the formulae (f) and (g), R₁Is hydrogen or straight chain C₁-C₂₀Alkyl radical, R₂Is hydrogen or straight chain C₁-C₂₀Alkyl, PO represents-CH₂-CH₂-O-and EO represents-CH₃-CH-CH₂-O-。

In some embodiments, the step of removing the non-exposed regions of the photoresist layer using a ketone-based developer is operated at a temperature range of about 10 ℃ to about 80 ℃. An advantage of having the temperature of the developer within the above range is that the solubility of the photoresist layer is reduced and thus the exposed areas of the photoresist layer may remain more.

The exposed region of the photoresist layer 110 has a plurality of protruding structures. In some embodiments, there is a first pitch P1, this first pitch P1 being the distance between the left sidewall surface of the first protruding structure and the left sidewall surface of the second protruding structure. In some embodiments, the first pitch P1 is about 10nm to about 40 nm.

Thereafter, as shown in fig. 1D, a portion of the material layer 104 is removed by performing an etching process and using the patterned photoresist layer 110a as a mask. In this way, the patterned material layer 104a is formed.

The etching process includes a number of etching operations. The etching process may be a dry etching process or a wet etching process. Thereafter, the patterned photoresist layer 110a is removed. In some embodiments, the patterned photoresist layer 110a is removed by a wet etching process including an alkaline solution, and the alkaline solution is tetraalkylammonium hydroxide. In some other embodiments, the patterned photoresist layer 110a is removed by a wet etching process including a Hydrogen Fluoride (HF) solution.

The adjuvant 14 in the photoresist layer 110 serves to enhance the absorption energy of the photoresist layer 110 during the exposure process 172. The radiant energy of the exposure process 172 can be reduced to about 3 millijoules (mJ) to about 20 millijoules (mJ) with the aid of the adjuvant 14. Furthermore, the Line Width Roughness (LWR) of the photoresist layer 110 is improved by about 3% to about 40%. In addition, Critical Dimension Uniformity (CDU) is also improved by about 3% to about 40%. Therefore, the development resolution is improved.

Again, by using a hydrophobic ketone-based solvent, the unexposed regions of photoresist layer 110 are removed, but the exposed regions of photoresist layer 110 are not removed. The dose of euv radiation is reduced because of the use of ketone-based solvents. Thus, a larger critical dimension of the patterned photoresist layer 110a can be obtained without increasing the radiation dose of the exposure process. Thereby improving the throughput of forming semiconductor device structures.

Fig. 2A-2C are schematic cross-sectional views of stages in the formation of a semiconductor structure, according to some embodiments of the present invention. The methods described in the embodiments of the present invention may be used in a variety of applications, such as finfet device structures. The processes and materials used to form the semiconductor device structure illustrated in fig. 2A-2C may be the same as or similar to those used to form the semiconductor device structure illustrated in fig. 1A-1D, and will not be repeated here.

As shown in fig. 2A, a patterned photoresist layer 110a is formed by performing a developing process 180. However, some residue from the unreacted inorganic material 12 or adjuvant 14 is not removed by the development process 180. The patterned photoresist layer 110a has a protruding bottom. The bottom of the protrusion may affect the subsequent patterning process.

As illustrated in fig. 2B, to remove unwanted residues, a cleaning process 182 may be performed on the patterned photoresist layer 110a as needed. The cleaning process 182 is configured to remove residues that are not completely removed by the developing process 180. In some embodiments, the development process 180 operates for a time in the range of about 15 seconds to about 150 seconds. In some embodiments, the cleaning process 182 operates for a time in the range of about 15 seconds to about 150 seconds.

The cleaning process 182 includes using a rinsing solvent. In some embodiments, the rinse solvent comprises a developer and an additive, wherein the developer comprises, for example, a ketone-based solvent as shown in tables 1-9 or an ester-based solvent as shown in tables 10-15. In some other embodiments, the rinse solvent is made primarily of the developer used in the development process 180, the difference between the rinse solvent and the developer being an additive. In some embodiments, the rinse solvent is different from the developer used in the development process 180, and the rinse solvent includes an amide, alcohol, ether, or glycol (diol) solvent.

The additives used in the rinse solvent in the cleaning process 182 include an acid, and this acid has a pka in the range of-4 to 8. The concentration of the additive in the rinse solvent in the cleaning process 182 is in the range of about 100ppm to about 50000 ppm.

In some embodiments, the additives used in the cleaning process 182 include formic acid, acetic acid, propionic acid, chloroacetic acid, dichloroacetic acid, trichloroacetic acid, butyric acid, valeric acid, oxalic acid, maleic acid, acrylic acid, hydrochloric acid, nitric acid, boric acid, sulfuric acid, carbonic acid, phosphoric acid, hydrofluoric acid, and the like,Hypochlorous acid, trifluoroacetic acid, hydrogen peroxide (H)₂O₂) Tetra-n-butylammonium fluoride (TBAF), or a combination thereof.

In some embodiments, the additive used in the cleaning process 182 is tetra-n-butylammonium fluoride. In some embodiments, the additive used in the cleaning process 182 is acetic acid. In some other embodiments, the additive used in the cleaning process 182 is oxalic acid.

Fig. 4A-4D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The methods described in the embodiments of the present invention may be used in a variety of applications, such as finfet device structures. The processes and materials used to form the semiconductor device structures illustrated in fig. 4A-4D may be the same as or similar to those used to form the semiconductor device structures illustrated in fig. 1A-1D, and will not be repeated here.

As shown in fig. 4A, a modification layer 109 is formed on the material layer 104, and a photoresist layer 110 is formed on the modification layer 109. The finish 109 includes an adjuvant 14. The adjuvant 14 may include a photoacid generator (PAG), a matting agent (Q), a crosslinking agent, or a photobase generator (PBG). The materials of adjuvant 14 are described in detail above and will not be repeated here for the sake of brevity. The photoresist layer 110 includes an inorganic material 12 and a solvent. The inorganic material 12 is uniformly distributed in the solvent. The inorganic material 12 includes a plurality of metal cores 122 and a plurality of first linking groups (L)₁)124, and a first linking group (L)₁)124 are bonded to the metal core 122.

The photoresist layer 110 has a first thickness T₁The modifying layer 109 has a second thickness T₂. In some embodiments, the first thickness T₁Greater than the second thickness T₂. In some embodiments, the first thickness T₁Relative to the second thickness T₂The ratio of (a) is in the range of about 5% to about 20%.

Thereafter, as illustrated in fig. 4B, according to some embodiments of the present invention, a mask 10 is formed on the photoresist layer 110, and an exposure process 172 is performed on the photoresist layer 110 to form an exposed region and an unexposed region.

After the exposure process 172, the second linking group L of the adjuvant 14₂And a third linking group L₃To the first linking group (L) on the metal core 122₁)124 react to form a plurality of chemical bonds between the inorganic material 12 and the adjuvant 14. The chemical reaction between adjacent metal cores 122 is accelerated with the aid of the adjuvant 14. Compound 16 is formed in photoresist layer 110, wherein the size of compound 16 is greater than the size of one of metal cores 122. More specifically, compared to having the first linking group (L)₁)124, compound 16 has a larger average molecular weight.

Next, as shown in fig. 4C, according to some embodiments of the invention, the photoresist layer 110 and the modification layer 109 are developed by performing a developing process 180 to form a patterned photoresist layer 110a and a patterned modification layer 109 a. In some embodiments, the photoresist layer 110 and the modifying layer 109 are developed simultaneously. In some embodiments, the photoresist layer 110 is patterned before the modifying layer 109 is patterned. In some embodiments, compound 16 is closer to the interface between modification layer 109 and photoresist layer 110 than inorganic material 12.

In some embodiments, a negative tone development process is performed, leaving exposed regions of the photoresist layer 110, and unexposed regions of the photoresist layer 110 are removed by a developer. After the exposure process 172 is performed, the exposed regions of the photoresist layer 110 become more hydrophilic, and thus, the unexposed regions of the photoresist layer 110 are removed using an organic solvent.

In some embodiments, the Negative Tone Development (NTD) process developer comprises a ketone-based solvent, an ester-based solvent, or a combination thereof. The ketone-based solvent has a total number of carbon atoms in the range of 5 to 15. In some embodiments, the ketone-based solvent has formula (a):

wherein R is₁Is straight-chain or branched C₁-C₅Alkyl radical, R₂Is straight-chain or branched C₃-C₉An alkyl group. Detailed examples of the ketone-based solvent are described in tables 1 to 9. In some embodiments, the developer comprises 3-heptanone, 4-heptanone, 2-octanone, 5-methyl-2-hexanone, 2, 4-dimethyl-3-pentanone, or a combination thereof.

In some embodiments, the Negative Tone Development (NTD) process developer includes an ester-based solvent, and the ester-based solvent has a total number of carbon atoms in a range of 5 to 14. In some embodiments, the ester-based solvent has formula (b):

wherein R is₃Is straight-chain or branched C₁-C₅Alkyl, or straight or branched C₂Alkoxy radical, and R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₃-C₆An alkoxy group. Detailed examples of the ester-based solvent are described in tables 10 to 15. In some embodiments, the developer is an ester-based solvent, and the ester-based solvent is a co-solvent (co-solvent) comprising 30 wt% to about 75 wt% butyl acetate and 25 wt% to about 70 wt% 1-methoxy-2-propanol acetate.

In some embodiments, the patterned photoresist layer 110a may be subjected to a cleaning process 182 as needed to remove unwanted residues. The cleaning process 182 includes using a rinsing solvent. In some embodiments, the rinse solvent includes a developer and an additive, where the developer includes, for example, a ketone-based solvent or an ester-based solvent.

Thereafter, as shown in fig. 4D, a portion of the material layer 104 is removed by performing an etching process and using the patterned photoresist layer 110a and the patterned modifying layer 109a as a mask. In this way, the patterned material layer 104a is formed. Thereafter, the patterned photoresist layer 110a is removed.

Fig. 5A-5E are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The methods described in the embodiments of the present invention may be used in a variety of applications, such as finfet device structures. The processes and materials used to form the semiconductor device structures illustrated in fig. 5A-5E may be the same as or similar to the processes and materials used to form the semiconductor device structures illustrated in fig. 1A-1D, and will not be repeated here.

As shown in fig. 5A, a modification layer 109 is formed on the photoresist layer 110. The finish 109 includes an adjuvant 14. Adjuvant 14 may include a photoacid generator, a quencher, a cross-linking agent, or a photobase generator. The materials of adjuvant 14 have been described in detail above and are omitted herein for brevity. The photoresist layer 110 includes an inorganic material 12 and a solvent. The inorganic material 12 is uniformly distributed in the solvent. The inorganic material 12 includes a plurality of metal cores 122 and a plurality of first linking groups (L)₁)124, wherein the first linking group (L)₁)124 are bonded to the metal core 122.

Thereafter, as shown in fig. 5B, according to some embodiments of the invention, a mask 10 is formed on the modification layer 109, and an exposure process 172 is performed on the modification layer 109 and the photoresist layer 110.

After the exposure process 172, the second linking group L of the auxiliary 14 in the modification layer 109₂And a third linking group L₃Reacts with the first bonding groups 124 on the metal core 122 in the photoresist layer 110, thereby forming a plurality of chemical bonds between the inorganic material 12 and the adjuvant 14.

Thereafter, as shown in fig. 5C, according to some embodiments of the invention, the modification layer 109 is developed by performing the first developing process 180 to form the patterned modification layer 109 a. In addition, a portion of the photoresist layer 110 is also removed. In some embodiments, a negative tone development process is performed to leave exposed regions of modification layer 109 and remove unexposed regions of modification layer 109 by a ketone-based solvent, an ester-based solvent, or a combination thereof. Detailed examples of the ketone-based solvent are described in tables 1 to 9. In some embodiments, the developer comprises 3-heptanone, 4-heptanone, 2-octanone, 5-methyl-2-hexanone, 2, 4-dimethyl-3-pentanone, or a combination thereof. Detailed examples of the ester-based solvent are described in tables 10 to 15. In some embodiments, the developer is an ester-based solvent, and this ester-based solvent is a co-solvent comprising 30 wt% to about 75 wt% butyl acetate and 25 wt% to about 70 wt% 1-methoxy-2-propanol acetate.

Next, as shown in fig. 5D, according to some embodiments of the invention, the photoresist layer 110 is developed by performing a second developing process 181 to form a patterned photoresist layer 110 a. Compound 16 is closer to the interface between modification layer 109 and photoresist layer 110 than metal core 122.

Next, as shown in fig. 5E, a portion of the material layer 104 is removed by performing an etching process and using the patterned photoresist layer 110a and the patterned modifying layer 109a as a mask. In this way, the patterned material layer 104a is formed. Then, the patterned photoresist layer 110a and the patterned modifying layer 109a are removed.

Fig. 6A-6G are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The methods described in the embodiments of the present invention may be used in a variety of applications, such as finfet device structures. The processes and materials used to form the semiconductor device structure illustrated in fig. 6A-6G may be the same as or similar to those used to form the semiconductor device structure illustrated in fig. 1A-1D, and will not be repeated here.

As shown in fig. 6A, a tri-layer photoresist (tri-layer photoresist) layer 120 is formed on the material layer 104 on the substrate 102. The three-layer photoresist layer 120 includes a bottom layer 106, an intermediate layer 108, and a photoresist layer 110. The three-layer photoresist layer 120 is used to pattern the underlying material layer 104 and is subsequently removed.

A bottom layer 106 is formed over the material layer 104. The bottom layer 106 may be a first layer of a three-layer photoresist layer 120 (also referred to as a three-layer photoresist). The bottom layer 106 may comprise a material that is patternable and/or has anti-reflection (anti-reflection) properties. In some embodiments, the bottom layer 106 is a bottom anti-reflective coating (BARC) layer. In some embodiments, the underlayer 106 comprises a carbon backbone polymer (carbon backbone polymer). In some embodiments, the bottom layer 106 is formed of a silicon free (Si free) material. In some other embodiments, the bottom layer 106 comprises a novolac resin (novolac resin), for example, a chemical structure having a plurality of phenol units (phenol units) bonded together. In some embodiments, the bottom layer 106 is formed by a spin-on process, a chemical vapor deposition process, a physical vapor deposition process, and/or other suitable deposition processes.

Thereafter, an intermediate layer 108 is formed on the bottom layer 106, and a photoresist layer 110 is formed on the intermediate layer 108. In some embodiments, the bottom layer 106, the intermediate layer 108, and the photoresist layer (or top layer) 110 are referred to as a three-layer photoresist layer 120. The intermediate layer 108 may have a composition that provides anti-reflective properties and/or hard mask (hard mask) properties for a lithographic process. In addition, the middle layer 108 is designed to provide etch selectivity relative to the bottom layer 106 and the photoresist layer 110. In some embodiments, the intermediate layer 108 is formed of silicon nitride, silicon oxynitride, or silicon oxide. In some embodiments, the intermediate layer 108 includes a silicon-containing inorganic polymer. In some embodiments, the photoresist layer 110 includes a chemical structure as illustrated in fig. 3A.

Next, as shown in FIG. 6B, according to some embodiments of the invention, an exposure process (not shown) is performed on the photoresist layer 110 to form an exposed region and an unexposed region. Thereafter, the photoresist layer 110 is developed by a developer to form a patterned photoresist layer 110 a. In some embodiments, the developer is a ketone-based solvent. Detailed examples of the ketone-based solvent are described in tables 1 to 9. In some embodiments, the developer comprises 3-heptanone, 4-heptanone, 2-octanone, 5-methyl-2-hexanone, 2, 4-dimethyl-3-pentanone, or a combination thereof. In some embodiments, the developer is an ester-based solvent. Detailed examples of the ester-based solvent are described in tables 10 to 15. In some embodiments, the developer is an ester-based solvent, and this ester-based solvent is a co-solvent comprising 30 wt% to about 75 wt% butyl acetate and 25 wt% to about 70 wt% 1-methoxy-2-propanol acetate. After the exposure process, compound 16 is formed in photoresist layer 110.

In some embodiments, the patterned photoresist layer 110a may be subjected to a cleaning process as needed in order to remove unwanted residues. The cleaning process includes the use of a rinse solvent. In some embodiments, the rinse solvent includes a developer and an additive, where the developer includes, for example, a ketone-based solvent or an ester-based solvent.

Thereafter, as illustrated in fig. 6C, the patterned intermediate layer 108a is formed by removing a portion of the intermediate layer 108 using the patterned photoresist layer 110a as a mask, according to some embodiments of the present invention. In this manner, the pattern of the patterned photoresist layer 110a is transferred to the intermediate layer 108.

A portion of the intermediate layer 108 is removed by a dry etch process, a wet etch process, or a combination thereof. In some embodiments, the etch process comprises a plasma etch process, and this plasma etch process uses a fluorine-containing etchant, e.g., CF₂、CF₃、CF₄、C₂F₂、C₂F₃、C₃F₄、C₄F₄、C₄F₆、C₅F₆、C₆F₆、C₆F₈Or a combination of the foregoing.

Thereafter, as shown in fig. 6D, the patterned photoresist layer 110a is removed according to some embodiments of the present invention. In some embodiments, the patterned photoresist layer 110a is removed by a wet etching process or a dry etching process. In some embodiments, the patterned photoresist layer 110a is removed by a wet etch process including an alkaline solution, wherein the alkaline solution is tetraalkylammonium hydroxide.

Next, as illustrated in fig. 6E, the patterned bottom layer 106a is formed by removing a portion of the bottom layer 106 using the patterned middle layer 108a as a mask according to some embodiments of the invention. In this manner, the pattern of the patterned intermediate layer 108a is transferred to the bottom layer 106.

Thereafter, as illustrated in fig. 6F, a portion of the material layer 104 is doped by performing an ion implantation process 174 and using the patterned middle layer 108a and the patterned bottom layer 106a as masks, according to some embodiments of the invention. As such, the doped region 105 is formed in the material layer 104. P-type dopants (e.g., boron or boron difluoride (BF)) can be used₂) And/or n-type dopants (e.g., phosphorus or arsenic) to dope the doped region 105. Thereafter, the patterned middle layer 108a and the patterned bottom layer 106a are removed.

Figures 7A-7F are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The methods described in these embodiments may be used in a variety of applications, such as finfet device structures. Some of the processes and materials used to form the semiconductor device structures illustrated in fig. 7A-7F may be the same as or similar to some of the processes and materials used to form the semiconductor device structures illustrated in fig. 6A-6G, and will not be described again.

As shown in fig. 7A, a three-layer photoresist layer 120 is formed on the material layer 104. The intermediate layer 108 includes the adjuvant 14, and the adjuvant 14 is distributed in the solvent of the intermediate layer 108. Adjuvant 14 may include a photoacid generator, a quencher, a cross-linking agent, or a photobase generator. The photoresist layer 110 includes an inorganic material 12 and a solvent. The inorganic material 12 includes a first linking group (L)₁)124, and a first linking group (L)₁)124 are bonded to the metal core 122.

Thereafter, as illustrated in fig. 7B, according to some embodiments of the present invention, a mask 10 is formed on the photoresist layer 110, and an exposure process 172 is performed on the intermediate layer 108 and the photoresist layer 110.

After the exposure process 172, the second linking group L of the adjuvant 14 located in the intermediate layer 108₂And a third linking group L₃Reacts with the first bonding groups 124 on the metal core 122 in the photoresist layer 110, thereby forming a plurality of chemical bonds between the inorganic material 12 and the adjuvant 14. The reaction rate of the chemical reaction between the adjacent metal cores 122 is enhanced with the aid of the adjuvant 14.

Thereafter, as shown in fig. 7C, the photoresist layer 110 is developed by performing a developing process to form a patterned photoresist layer 110a according to some embodiments of the invention. Compound 16 is formed in photoresist layer 110. Compound 16 is formed by reacting inorganic material 12 with adjuvant 14. In some embodiments, the developer is a ketone-based solvent, an ester-based solvent, or a combination thereof. Detailed examples of the ketone-based solvent are described in tables 1 to 9. In some embodiments, the developer comprises 3-heptanone, 4-heptanone, 2-octanone, 5-methyl-2-hexanone, 2, 4-dimethyl-3-pentanone, or a combination thereof. Detailed examples of the ester-based solvent are described in tables 10 to 15. In some embodiments, the developer is an ester-based solvent, and this ester-based solvent is a co-solvent comprising 30 wt% to about 75 wt% butyl acetate and 25 wt% to about 70 wt% 1-methoxy-2-propanol acetate.

Thereafter, as illustrated in fig. 7D, the patterned intermediate layer 108a is formed by removing a portion of the intermediate layer 108 using the patterned photoresist layer 110a as a mask, according to some embodiments of the present invention. In this manner, the pattern of the patterned photoresist layer 110a is transferred to the intermediate layer 108. Thereafter, the substrate 102 is processed in a manner similar to that illustrated in fig. 6D to 6G. As a result, as shown in fig. 7F, a doped region 105 is formed in the material layer 104.

Figures 8A-8D are schematic cross-sectional views of stages in the formation of a semiconductor structure, in accordance with some embodiments of the present invention. The methods described in these embodiments may be used in a variety of applications, such as finfet device structures. Some of the processes and materials used to form the semiconductor device structures illustrated in fig. 8A-8D may be the same as or similar to those used to form the semiconductor device structures illustrated in fig. 6A-6G, and will not be described again.

As illustrated in fig. 8A, according to some embodiments of the present invention, a modification layer 109 is formed on the three-layer photoresist layer 120.

Next, as shown in fig. 8B, according to some embodiments of the invention, an exposure process (not shown) is performed on the modification layer 109 and the photoresist layer 110. After that, the modification layer 109 and the photoresist layer 110 are sequentially developed by two developers to form a patterned modification layer 109a and a patterned photoresist layer 110 a.

Thereafter, as shown in fig. 8C, according to some embodiments of the present invention, the patterned intermediate layer 108a is formed by removing a portion of the intermediate layer 108 using the patterned photoresist layer 110a and the patterned modifying layer 109a as a mask. In this manner, the pattern of the patterned photoresist layer 110a is transferred to the intermediate layer 108. Thereafter, the substrate 102 is processed in a manner similar to that illustrated in fig. 6D to 6G. As a result, as shown in fig. 8D, a doped region 105 is formed in the material layer 104.

Some embodiments for forming semiconductor device structures are provided herein. A material layer is formed on the substrate, and a photoresist layer is formed on the material layer. The photoresist layer includes an inorganic material and an adjuvant, and the inorganic material includes a plurality of metal cores and a plurality of first connecting groups, wherein the first connecting groups are bonded to the metal cores. The adjuvant comprises a plurality of second linking groups L₂And a plurality of third linking groups L₃. The second linking group L of the auxiliary agent is formed after the exposure process is performed on the photoresist layer₂And the third linking group L₃The first linking group L with the inorganic material₁Reacting to form a compound, whereinThe size of the compound is greater than the respective size of each metal core. The above-mentioned adjuvant can accelerate the first linking group L₁A second linking group L₂And a third linking group L₃Cross-linking reaction between them. In addition, a ketone-based solvent, an ester-based solvent, or a combination thereof is used to remove the unexposed regions of the photoresist layer. Since an auxiliary agent is added to the photoresist layer and a hydrophobic ketone-based solvent is used, the radiation energy of the exposure process can be reduced. Further, Line Width Roughness (LWR) of the photoresist layer is improved. Therefore, improvement in Line Critical Dimension Uniformity (LCDU) is achieved.

In some embodiments, methods of forming semiconductor structures are provided. The method includes forming a material layer on a substrate and forming a photoresist layer on the material layer. The photoresist layer includes an inorganic material and an adjuvant, and the inorganic material includes a plurality of metal cores and a plurality of first connecting groups, wherein the first connecting groups are bonded to the metal cores. The method includes exposing a portion of the photoresist layer, the photoresist layer including exposed and unexposed regions, and the adjuvant reacting with the first linking group in the exposed regions. The method also includes removing the unexposed region of the photoresist layer using a developer to form a patterned photoresist layer. The developer includes a ketone-based solvent, an ester-based solvent, or a combination thereof, wherein the ketone-based solvent has a substituted or unsubstituted C₆-C₇A cyclic ketone, the ester-based solvent having the formula (b):

In some embodiments, R₃Is CH₃，R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₂-C₆An alkoxy group.

In some embodiments, R₃Is C₂H₅，R₄Is straight-chain or branched C₄An alkyl group.

In some embodiments, R₃Is C₃H₇，R₄Is straight-chain or branched C₃-C₄An alkyl group.

In some embodiments, R₃Is C₄H₉，R₄Is straight-chain or branched C₂-C₄An alkyl group.

In some embodiments, R3 is C₅H₁₀R4 is linear C₂An alkyl group.

In some embodiments, R3 is C₂H₅O，R₄Is straight-chain or branched C₂-C₃An alkyl group.

In some embodiments, the auxiliary includes a plurality of second linking groups, and the second linking groups react with the first linking groups during the exposure process to form a plurality of chemical bonds between the auxiliary and the inorganic material.

In some embodiments, the step of removing the unexposed regions of the photoresist layer using a developer is performed at a temperature in a range of about 10 ℃ to about 80 ℃.

In some embodiments, the method further comprises: after the developer is used, a rinsing process is performed on the photoresist layer using a rinsing solvent.

In some embodiments, the rinsing solvent includes the developer and an additive, and the additive includes an acid.

In some embodiments, the acid comprises formic acid, acetic acid, propionic acid, chloroacetic acid, dichloroacetic acid, trichloroacetic acid, butyric acid, valeric acid, oxalic acid, maleic acid, acrylic acid, hydrochloric acid, nitric acid, boric acid, sulfuric acid, carbonic acid, phosphoric acid, hydrofluoric acid, hypochlorous acid, trifluoroacetic acid, or combinations thereof.

In some embodiments, methods of forming semiconductor structures are provided. The method includes forming a material layer on a substrate and forming a bottom layer on the material layer. The method also includes forming an intermediate layer over the bottom layer and forming a photoresist layer over the intermediate layer. The photoresist layer includes an inorganic material having a plurality of metal cores and a plurality of first linking groups, wherein the first linking groups are bonded to the metal cores. The method further includes forming a modification layer below or above the photoresist layer, wherein the modification layer includes an auxiliary agent. The method further includes performing an exposure process to expose a portion of the photoresist layer, during which the adjuvant reacts with the first linking group. The method includes developing the photoresist layer using a ketone-based solvent or an ester-based solvent having a substituted or unsubstituted C to form a patterned photoresist layer₆-C₇A cyclic ketone, the ester-based solvent having the formula (b):

In some embodiments, the method further comprises: developing the modification layer to form a patterned modification layer; patterning the intermediate layer using the patterned photoresist layer as a mask to form a patterned intermediate layer; removing the patterned photoresist layer and the patterned modifying layer; and patterning the bottom layer using the patterned intermediate layer as a mask to form a patterned bottom layer.

In some embodiments, the method further comprises: after using the ketone-based solvent or the ester-based solvent, the photoresist layer is subjected to a rinsing process, wherein the rinsing process includes a rinsing solvent.

In some embodiments, the rinsing solvent comprises an additive, and the additive comprises formic acid, acetic acid, propionic acid, chloroacetic acid, dichloroacetic acid, trichloroacetic acid, butyric acid, valeric acid, oxalic acid, maleic acid, acrylic acid, hydrochloric acid, nitric acid, boric acid, sulfuric acid, carbonic acid, phosphoric acid, hydrofluoric acid, hypochlorous acid, trifluoroacetic acid, or a combination thereof.

In some embodiments, the method further comprises: after exposing the portion of the photoresist layer, forming a compound in the exposed area of the photoresist layer, wherein the compound is made of the metal core, the second linking group and the first linking group, and the compound is not removed by the ketone-based solvent.

In some embodiments, methods of forming semiconductor structures are provided. The method includes forming a material layer on a substrate and forming a bottom layer on the material layer. The method includes forming an intermediate layer on the bottom layer and forming a photoresist layer on the intermediate layer. The photoresist layer includes an inorganic material including a plurality of first linking groups bonded to a plurality of metal cores and an adjuvant including a plurality of second linking groups. The method also includes performing an exposure process to expose a portion of the photoresist layer, wherein the second linking group reacts with the first linking group during the exposure process. The method includes removing a portion of the photoresist layer using an ester-based solvent to form a patterned photoresist layer, wherein the ester-based solvent has formula (b):

The method includes removing a portion of the intermediate layer using the patterned photoresist layer as a mask to form a patterned intermediate layer, and removing a portion of the bottom layer using the patterned intermediate layer as a mask to form a patterned bottom layer.

In some embodiments, the method further comprises: after using the ester-based solvent, performing a rinsing process on the photoresist layer, wherein the rinsing process includes a rinsing solvent, and the rinsing solvent includes the ester-based solvent and an additive.

The foregoing outlines features of many embodiments so that those skilled in the art may better understand the aspects of the present embodiments. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention. Various changes, substitutions, and alterations can be made hereto without departing from the spirit and scope of the invention.

Although the present invention has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method of forming a semiconductor structure, comprising:

forming a material layer on a substrate;

forming a photoresist layer over the material layer, wherein the photoresist layer comprises an inorganic material and an adjuvant, wherein the inorganic material comprises a plurality of metal cores and a plurality of first linking groups, and wherein the plurality of first linking groups are bonded to the plurality of metal cores;

exposing a portion of the photoresist layer, wherein the photoresist layer includes an exposed region and an unexposed region, and in the exposed region, the auxiliary reacts with the plurality of first linking groups; and

removing the unexposed region of the photoresist layer using a developer to form a patterned photoresist layer, wherein the developer comprises a ketone-based solvent, an ester-based solvent, or a combination thereof, wherein the ketone-based solvent has a substituted or unsubstituted C₆-C₇A cyclic ketone, the ester-based solvent having formula (b):

2. The method according to claim 1, wherein the auxiliary agent comprises a plurality of second linking groups, and the plurality of second linking groups react with the plurality of first linking groups during the exposure process to form a plurality of chemical bonds between the auxiliary agent and the inorganic material.

3. The method according to claim 1, wherein the step of removing the unexposed regions of the photoresist layer using a developer is performed at a temperature in a range from about 10 ℃ to about 80 ℃.

4. The method of forming a semiconductor structure of claim 1, further comprising:

after the developer is used, a rinsing process is performed on the photoresist layer using a rinsing solvent.

5. A method of forming a semiconductor structure, comprising:

forming a material layer on a substrate;

forming a bottom layer on the material layer;

forming a middle layer on the bottom layer;

forming a photoresist layer on the intermediate layer, wherein the photoresist layer comprises an inorganic material having a plurality of metal cores and a plurality of first connecting groups, wherein the plurality of first connecting groups are bonded to the plurality of metal cores;

forming a modifying layer below or above the photoresist layer, wherein the modifying layer comprises an auxiliary agent;

performing an exposure process to expose a portion of the photoresist layer, wherein the adjuvant reacts with the plurality of first linking groups during the exposure process; and

developing the photoresist layer using a ketone-based solvent or an ester-based solvent to form a patterned photoresist layer, wherein the ketone-based solvent has a substituted or unsubstituted C₆-C₇A cyclic ketone, the ester-based solvent having formula (b):

6. The method of forming a semiconductor structure of claim 5, further comprising:

developing the modified layer to form a patterned modified layer;

patterning the intermediate layer using the patterned photoresist layer as a mask to form a patterned intermediate layer;

removing the patterned photoresist layer and the patterned modifying layer; and

the bottom layer is patterned using the patterned middle layer as a mask to form a patterned bottom layer.

7. The method of forming a semiconductor structure of claim 5, further comprising:

after using the ketone-based solvent or the ester-based solvent, a rinsing process is performed on the photoresist layer, wherein the rinsing process includes a rinsing solvent.

8. A method of forming a semiconductor structure, comprising:

forming a material layer on a substrate;

forming a bottom layer on the material layer;

forming a middle layer on the bottom layer;

forming a photoresist layer on the intermediate layer, wherein the photoresist layer comprises an inorganic material and an adjuvant, wherein the inorganic material comprises a plurality of first connecting groups bonded to a plurality of metal cores, and the adjuvant comprises a plurality of second connecting groups;

performing an exposure process to expose a portion of the photoresist layer, wherein the second linking groups react with the first linking groups during the exposure process;

removing a portion of the photoresist layer using an ester-based solvent to form a patterned photoresist layer, wherein the ester-based solvent has formula (b):

wherein R is₃Is straight-chain or branched C₁-C₅Alkyl, or straight or branched C₂Alkoxy radical, and R₄Is straight-chain or branched C₂-C₆Alkyl, or straight or branched C₃-C₆An alkoxy group;

removing a portion of the intermediate layer using the patterned photoresist layer as a mask to form a patterned intermediate layer; and

a portion of the bottom layer is removed using the patterned middle layer as a mask to form a patterned bottom layer.

9. The method of forming a semiconductor structure of claim 8, further comprising:

after exposing the portion of the photoresist layer, forming a compound in an exposed region of the photoresist layer, wherein the compound is made up of the plurality of metal cores, the plurality of second linking groups, and the plurality of first linking groups, and the compound is not removed by the ketone-based solvent.

10. The method of forming a semiconductor structure of claim 8, further comprising:

after the ester-based solvent is used, a rinsing process is performed on the photoresist layer, wherein the rinsing process includes a rinsing solvent, and the rinsing solvent includes the ester-based solvent and an additive.