A resin composition and a method for patterning a photoresist using the same

Abstract

The present invention relates to a resin composition comprising the following components: (A) alkali-soluble resin, 10 to 30 wt%; (B) solvent, 70 to 90 wt%, preferably 75 to 85 wt%; (C) surfactant, 0.005 to 0.5 wt%, preferably 0.01 to 0.4 wt%; (D) adhesion aid, 0.01 to 20 wt%, preferably 0.1 to 15 wt%, more preferably 0.1 to 10 wt%, the sum of the components being 100 wt%. It also relates to a method for patterning a photoresist using the resin composition. The resin composition, as a bottom sacrificial layer photoresist, can precisely control the undercut width by controlling the alkali-solubility rate after development, and thus by setting the development time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photoresist, in particular to a photoresist for bottom sacrificial layer, and the present application also relates to a method for patterning using the photoresist for bottom sacrificial layer, and a method for precisely controlling the photoetching window by controlling the developing time of the photoresist for bottom sacrificial layer. BACKGROUND

[0002] In the process of semiconductor manufacturing, metal patterns are usually used to make the leads and electrodes of the device, and the metal patterns are usually formed by the method of photoetching and then wet etching or dry etching. However, some metals are difficult to be patterned by wet etching or dry etching, and the chemicals used for etching these metal patterns will corrode other parts of the semiconductor device. Therefore, a lift-off process is usually used to make the patterns of these metals.

[0003] In the lift-off process, a photoresist mask with a corresponding pattern is first made on the substrate of the metal, then a metal film is evaporated or sputtered on the photoresist mask, and finally the photoresist mask and the metal layer on it are removed by a stripping solution, so as to obtain the desired metal pattern. During the lift-off process, the photoresist has an absorption effect on light, and the light energy obtained by the photoresist from the surface to the bottom layer gradually decreases during the exposure process, resulting in a gradual decrease in the developing speed from the surface to the bottom layer. After development, the sidewall of the photoresist is narrow at the top and wide at the bottom, and has a certain slope. Therefore, during the metal deposition process, metal particles will deposit on the slope, and the photoresist will be completely covered by the metal. When the photoresist is removed, it is not clean, which increases the difficulty of stripping.

[0004] The traditional negative photoresist lift-off process uses an inverted trapezoidal structure with a wide top and a narrow bottom, which reduces the difficulty of metal stripping and improves the efficiency of stripping. However, the preparation process is complex, and an additional exposure step or an additional post-exposure cross-linking baking step is usually required to control the undercut depth of the bottom layer of the photoresist, which is complex and costly.

[0005] In addition, the bottom layer of the current double-layer structure photoresist in actual production also has certain photosensitive properties, so there will be problems of mutual mismatch with the top layer positive or negative photoresist mask, and the double exposure and overlay process is a challenge to the overlay accuracy of the exposure equipment, and the subsequent photoresist edge roughness and resolution, thereby affecting the production stability.

[0006] In addition, the traditional photoresist contains photosensitive and active components, making the storage and transportation conditions of the traditional photoresist more stringent. SUMMARY

[0007] The present invention is to provide a photoresist used as a bottom sacrificial layer, to provide a process for forming and transferring a pattern in a double-layer photoresist process with only one photoetching, and more particularly to provide a method for forming a pattern in a double-layer photoresist, and a method for precisely controlling a photoetching window by controlling a developing time of the bottom sacrificial layer photoresist.

[0008] More particularly, the present invention provides a resin composition comprising the following components:

[0009] (A) an alkali-soluble resin, 10 to 30 wt% ;

[0010] (B) a solvent, 70 to 90 wt%, preferably 75 to 85 wt% ;

[0011] (C) a surfactant, 0.005 to 0.5 wt%, preferably 0.01 to 0.4 wt%, more preferably 0.05 to 0.4 wt% ;

[0012] (D) an adhesion aid, 0.02 to 20 wt%, preferably 0.1 to 15 wt%, more preferably 0.1 to 10 wt%,

[0013] based on the total weight of the resin composition, and the sum of the components is 100 wt%.

[0014] The present invention provides a method for forming a pattern in a photoresist, comprising the following steps:

[0015] (i) uniformly coating the above resin composition on a substrate to form a bottom sacrificial layer photoresist, preferably, the substrate is selected from a glass substrate, a silicon substrate, a sapphire substrate, a silicon carbide substrate, a compound semiconductor substrate;

[0016] (ii) baking the resist film obtained in (i) at a temperature of 90 to 200°C, preferably 110 to 150°C, to remove the solvent, and the thickness of the bottom sacrificial layer photoresist after baking is 0.1 to 8 μm, more preferably 0.1 to 6 μm;

[0017] (iii) uniformly coating a positive photoresist or a negative photoresist on the bottom sacrificial layer photoresist baked in (ii), preferably pre-baking the positive or negative photoresist at a temperature of 90 to 150°C;

[0018] (iv) partially irradiating the photoresist formed in (iii) through a mask using a ray, preferably, the ray is selected from a g-ray, an i-ray, a KrF excimer laser, an ArF excimer laser, an extreme ultraviolet EUV ray, an electron beam ray, an ion beam ray, an x-ray, preferably a ray comprising a g-ray, an h-ray and / or an i-ray;

[0019] (v) developing the photoresist film obtained in (iv) using a developing solution;

[0020] (vi) optionally baking the developed photoresist at 120 to 180 °C, preferably 120 to 150 °C, to make the film more complete.

[0021] wherein if a positive photoresist is uniformly coated on the underlayer sacrificial layer, i.e. in step (iii), the method of patterning the photoresist is carried out according to the above steps (i) to (vi). Wherein if a negative photoresist is uniformly coated on the underlayer sacrificial layer, i.e. in step (iii), the following step is added after step (iv) before step (v): baking the photoresist film after exposure in step (iv) at a temperature of 90 to 130 °C (Post Exposure Bake) to solidify the photoresist film layer in the exposed area.

[0022] The present application also relates to the use of the above-mentioned photoresist patterning method for metal patterning in semiconductor manufacturing.

[0023] The photoresist for underlayer sacrificial layer of the present application can achieve the desired underlayer sacrificial layer photoresist undercut shape by designing its post-exposure alkali dissolution rate, and then designing different developing times, and precisely control the undercut window after photoresist development, i.e. control the undercut width, to meet the customer's customized needs. In addition, the underlayer sacrificial layer photoresist of the present application does not contain a photosensitizer, thus also providing the advantage of storage stability, which can be stored for a long time in different environments, and is convenient for transportation. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A schematic diagram showing the undercut window of the underlayer sacrificial layer photoresist relative to the upper layer photoresist, wherein the undercut window is an inverted trapezoidal structure, wherein a is the undercut width, b is the distance between the upper and lower bottoms of the underlayer sacrificial layer after photoresist development (i.e. the undercut height), 11 is the substrate / substrate, 12 is the underlayer sacrificial layer photoresist, and 13 is the upper layer positive / negative photoresist.

[0025] DEFINITIONS

[0026] Unless otherwise defined, the terms used herein have the meanings commonly understood by those of ordinary skill in the art.

[0027] As used herein, the term "undercut window" refers to a phenomenon in a photolithography process for manufacturing a semiconductor, when a photoresist has two layers, after the photoresist is developed after exposure, a undercut structure is formed at the lower edge of the top layer photoresist due to the dissolution rate of the bottom layer resist is greater than that of the top layer photoresist, in the present invention the undercut structure is an inverted trapezoidal structure. The width of the undercut window is the depth of the bottom layer resist dissolved compared to the vertical face of the upper layer photoresist, as shown in Figure 1

[0028] As used herein, "film thickness apparent dissolution time" refers to the time required for the film layer formed by the resin composition or photoresist to be completely dissolved (for positive photoresist, the exposed area; for negative photoresist, the non-exposed area) under a given developing medium and manner.

[0029] As used herein, the term "photoresist" (also known as "photoresist") is a key material required in the photolithography process for manufacturing ultra-large scale integrated circuits (IC; also known as "semiconductor", commonly known as "chip"). It has been constantly updated with the development speed of Moore's Law. Photoresist is a photosensitive polymer whose solubility changes when exposed to, for example, ultraviolet light. When the exposed photoresist is contacted with a developing solution (usually an alkaline solution), the exposed area is dissolved by the photoresist, which is a positive photoresist, and vice versa, which is a negative photoresist. Photoresist can also be classified as polyacrylate, fused ring olefin addition, cycloolefin maleic anhydride copolymer, silicon-containing copolymer, multi-component copolymer system, and small molecule material, etc. At the same time, photoresist is generally coated on the substrate by spraying, pulling, rolling, centrifugation and flow method, etc. For the convenience of description, the resin composition used for the bottom sacrificial layer in this paper is also called photoresist, although it does not undergo crosslinking and curing under light.

[0030] As used herein, the term "mask" refers to a photomask, also known as a mask, a photomask, a photolithography mask, etc. It is a patterned mother plate used in the photolithography process in microelectronic manufacturing. The opaque light-shielding film on the transparent substrate forms a mask pattern, and the pattern is transferred to the product substrate through exposure. The mask is a pattern "negative" in the chip manufacturing process, used to transfer high-precision circuit design.

[0031] As used herein, the term "(n+1) valent linear alkyl" or "(n+1) valent cycloalkyl", for example, (n+1) valent linear alkyl or cycloalkyl with 1 to 20 carbon atoms, refers to a group obtained by removing n hydrogen atoms from, for example, a linear or branched alkyl group with 1 to 20 carbon atoms or a cycloalkyl group.

[0032] ​In the present application, the term "alkali-soluble resin" is used synonymously with "solid content of an alkali-water-soluble resin" unless otherwise stated. This is because, in use, "alkali-soluble resin" usually contains a solvent component (e.g. for lowering the viscosity, easy handling), whereas, for example, in connection with the calculation of material ratios, determination of acid values, etc., only the component free of solvent is usually taken into account, as is well known to the person skilled in the art. DETAILED DESCRIPTION

[0033] In the present application, all operations are carried out at room temperature, under normal pressure, unless otherwise stated.

[0034] The present application provides a resin composition comprising the following components:

[0035] (A) an alkali-soluble resin, 10 to 30% by weight;

[0036] (B) a solvent, 70 to 90% by weight, preferably 75 to 85% by weight;

[0037] (C) a surfactant, 0.005 to 0.5% by weight, preferably 0.01 to 0.4% by weight, more preferably 0.05 to 0.4% by weight;

[0038] (D) an adhesion aid, 0.02 to 20% by weight, preferably 0.1 to 15% by weight, more preferably 0.1 to 10% by weight,

[0039] based on the total weight of the resin composition, and the sum of the components is 100% by weight.

[0040] The alkali-soluble resin in the present application can be:

[0041] - a novolak resin, for example obtained by condensation of phenol, m-cresol, p-cresol, xylenol, mesitylenol, etc. phenols with formaldehyde, 2-hydroxybenzaldehyde, 3-hydroxybenzaldehyde, 4-hydroxybenzaldehyde, etc. aldehydes in the presence of an acid catalyst;

[0042] - a hydroxystyrene-based resin, for example a homopolymer of hydroxystyrene or a copolymer of hydroxystyrene with another styrene-based monomer, a copolymer of hydroxystyrene with acrylic acid or methacrylic acid or a derivative thereof;

[0043] - an acrylic acid or methacrylic acid-based resin, for example a copolymer of acrylic acid or methacrylic acid with a derivative thereof.

[0044] The resin of the present application is prepared by the radical polymerization of monofunctional unsaturated monomers in a solvent system initiated by a thermal initiator at a certain temperature. The resin of the present application can be prepared by three methods as follows: one is to drop the mixed monomers and radical initiator in a proper solvent into the solvent at a certain temperature; the other is to drop the mixed monomers and radical initiator into the solvent at a certain temperature after the monomers and radical initiator are completely dissolved in the solvent; the third is to drop the mixed monomers and radical initiator into the solvent at a certain temperature after part of the monomers are mixed with the solvent and heated to a certain temperature. The above three methods are mainly to solve the problems of heat release, dissolution, molecular weight control and reaction control in the synthesis process, and are selected according to different monomers, different combination ratios, different radical initiators and different solvent systems. The present application illustrates three synthesis methods of the resin of the present application, but is not limited to the three methods.

[0045] In one embodiment of the present application, the alkali-soluble resin of the present application is preferably polymerized from a plurality of monomers, and the alkali-soluble resin comprises at least one of the compounds represented by 1a and 1b below, both of the compounds 1a and 1b account for 20 to 60% by weight based on the weight of the alkali-soluble resin, and the monomers for synthesizing 1a and 1b are the monomers for synthesizing the alkali-soluble resin of the present application.

[0046]

[0047] wherein in (1a) and (1b), R is each independently a hydrogen atom, a methyl group, a hydroxymethyl group, a cyano group or a trifluoromethyl group. R 1 and R 2 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms. The alkyl group having 1 to 4 carbon atoms is selected from a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a t-butyl group. R 5 and R 6 are each independently an (n+1)-valent organic group selected from an (n+1)-valent chain hydrocarbon group having 1 to 20 carbon atoms, an (n+1)-valent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or an (n+1)-valent aromatic hydrocarbon group having 6 to 20 carbon atoms, or a combination thereof. Also, part or all of the hydrogen atoms of these groups can be substituted. n is each independently an integer of 1 to 3. In the case where n is greater than 2, R 1 and R 2 may be the same or different.

[0048] In an embodiment of the present application, the (n+1)-valent linear or branched alkyl group having a carbon number of 1 to 20 can be, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-methylpropyl, 1-methylpropyl, t-butyl.

[0049] In an embodiment of the present application, the (n+1)-valent alicyclic hydrocarbon group having a carbon number of 3 to 20 can be, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, adamantyl.

[0050] In an embodiment of the present application, the (n+1)-valent aromatic hydrocarbon group having a carbon number of 6 to 20 can be, for example, a group obtained by removing n number of hydrogen atoms from a 1-valent aromatic hydrocarbon group having a carbon number of 6 to 20, and the like.

[0051] In an embodiment of the present application, R 5 is preferably methylene, ethylene, 1,3-propylene or 1,2-propylene, propylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decamethylene, undecamethylene, dodecamethylene, tridecamethylene, tetradecamethylene, pentadecamethylene, hexadecamethylene, heptadecamethylene, octadecamethylene, nonadecamethylene, eicosylene, 1-methyl-1,3-propylene, 2-methyl-1,3-propylene, 2-methyl-1,2-propylene, 1-methyl-1,4-butylene, 2-methyl-1,4-butylene, methylidene, ethylidene, propylidene, 2-methylcyclohexylidene, 1,5-cyclooctylidene, norbornylidene, 1,5-adamantylidene, 2,6-adamantylidene, 1,3-phenylene, 1,4-phenylene, or an aromatic hydrocarbon group, or a combination thereof, more preferably methylene, ethylene, 1,2-propylene, 1,4-phenylene. Furthermore, R 6 is preferably 1,3-phenylene or 1,4-phenylene, more preferably 1,4-phenylene.

[0052] In a preferred embodiment of the present application, for compound 1a, n is preferably 1, R 1 and R 2 are the same and are preferably methyl, and R 5 is preferably methylene, ethylene, 1,2-propylene or 1,4-phenylene.

[0053] In a preferred embodiment of the present application, for compound 1b, n is preferably 1, R 1 and R 2 are the same and are preferably methyl, and R 6 is preferably 1,4-phenylene.

[0054] In one embodiment of the present application, wherein the acrylic or methacrylic resin of the present application is prepared by copolymerization of methacrylic acid, methyl methacrylate and at least one monomer selected from the group consisting of hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, preferably by copolymerization of methacrylic acid, methyl methacrylate, cyclohexyl methacrylate, hydroxyethyl methacrylate.

[0055] In one embodiment of the present application, wherein the acrylic or methacrylic resin of the present application is prepared by copolymerization of at least three monomers selected from the group consisting of methacrylic acid, methyl methacrylate, cyclohexyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate.

[0056] The monomers of the present application are preferably hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate.

[0057] In one embodiment of the present application, wherein the weight ratio of the monomers used in the preparation of the alkali-soluble resin of the present application, methacrylic acid, methyl methacrylate, hydroxyethyl methacrylate is 1.0:10.0:5.0 to 1.0:2.5:1.5, preferably 1.0:7.6:3.0 to 1.0:4.3:1.88.

[0058] In the present application, it is to be noted that in the composition of the resin monomers, the non-functional monomers are (meth)acrylate monomers having a carbon chain length of 4 to 20; aromatic styrene monomers such as ortho-vinyl toluene, meta-vinyl toluene, ortho-chlorostyrene; ethylene (propylene) compounds such as (meth)acrylamide, (meth)acrylanilide, (meth)acrylonitrile, vinyl toluene. These polymerization monomers can be used alone or in combination of two or more, but the non-functional monomers account for 5 to 90% of the resin monomers, preferably 10 to 80%, more preferably 20 to 70%, based on the weight of the alkali-soluble resin. The non-functional monomers are selected as appropriate depending on the properties of the resin to be synthesized.

[0059] In the present application, the free radical initiator used in the preparation of the alkali-soluble resin is typically an organic peroxide initiator (such as t-butyl hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, benzoyl peroxide, cyclohexyl peroxide, t-butyl peroxide) and an azo initiator (such as azobis isobutyronitrile, azobis isoheptyl nitrile, methyl azobis isobutyrate), among which, dicumyl peroxide, di-t-butyl peroxide, azobis isobutyronitrile, azobis isoheptyl nitrile are preferably used. The initiator can be used alone or in combination of two or more.

[0060] The solvent used in the present application can be typically:

[0061] - alcohol solvents such as ethylene glycol, propylene glycol, diethylene glycol, 3-methoxybutanol, 2-methylpentanol, 2-ethylbutanol, 2,6-dimethyl-4-heptanol, secondary undecyl alcohol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diethylene glycol, triethylene glycol,

[0062] - ether solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diethylene glycol diethyl ether, tetrahydrofuran;

[0063] - ketone solvents such as methyl ketone, butanone, cyclohexanone, heptanone;

[0064] - aromatic hydrocarbon solvents such as toluene, xylene;

[0065] - amide solvents such as N-methylpyrrolidone, N,N-dimethylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide.

[0066] Here, it is important to note that since the alkali-soluble resin in the present application is resistant to ester solvents, i.e., ensures that the synthesized resin compound does not dissolve in ester solvents, which is the basis for achieving a double-layer structure, ester solvents are not used in the synthesis of the resin of the present application. The total amount of the solvent used in the polymerization reaction of the alkali-soluble resin in the present application is not particularly limited, and is typically 10 to 80 parts by weight, preferably 30 to 60 parts by weight, based on 100 parts by weight of the total amount of the alkali-soluble resin.

[0067] In a preferred embodiment of the present application, wherein the solvent of the present application is selected from one or a mixture of two or more of propylene glycol monoalkyl ether, propylene glycol monoalkyl ether acetate, alkyl lactate, and γ-butyrolactone, preferably propylene glycol monomethyl ether.

[0068] In an embodiment of the present application, wherein the weight ratio of the total amount of the monomers of the present application to the solvent used in the polymerization reaction for synthesizing the alkali-soluble resin is preferably 1 : 1.2 to 1 : 2.

[0069] In a specific embodiment of the present application, the reaction temperature, the dropping time, and the reaction time for synthesizing the alkali-soluble resin of the present application are selected depending on the polymerization monomers, the free radical initiator, and the type of solvent used. The reaction temperature is 30 to 200°C, preferably 40 to 180°C, and more preferably 50 to 150°C. The dropping time is 10 minutes to 10 hours, preferably 30 minutes to 8 hours, and more preferably 1 hour to 5 hours. The reaction time after dropping is 1 hour to 20 hours, preferably 3 hours to 15 hours, and more preferably 5 hours to 10 hours. In addition, the dropping method can be single-port unit position dropping, multi-port multi-position dropping, and immersion dropping.

[0070] In the present application, it is important to note that the carboxyl groups in the alkali-soluble resin are provided by a monofunctional unsaturated monomer having a carboxyl group such as (meth)acrylic acid, and the acid value of the solid content of the resin is 10 to 300 mg KOH / g, preferably 20 to 200 mg KOH / g, more preferably 30 to 100 mg KOH / g, measured according to GB / T 2895-2008.

[0071] In the present application, it is important to note that the hydroxyl groups in the resin can be provided by a monomer selected from the group consisting of hydroxy (meth) acrylate such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate; ethoxylated hydroxyethyl (meth) acrylate, and the hydroxyl value of the solid content of the alkali-soluble resin is 10 to 800 mg KOH / g, preferably 30 to 500 mg KOH / g, more preferably 50 to 300 mg KOH / g, measured according to DIN 53240-2:2007-11.

[0072] In one embodiment of the present application, the weight average molecular weight of the alkali-soluble resin of the present application is 1,000 to 100,000, preferably 2,000 to 80,000, more preferably 3,000 to 50,000, and the distribution width of the molecular weight (polydispersity: the ratio of the weight average molecular weight to the number average molecular weight Mw / Mn) is 1 to 5, preferably 1 to 3, more preferably 1.5 to 2.5, wherein the weight average molecular weight of the alkali-soluble resin of the present application is measured according to GB / T 7193-2008 using gel permeation chromatography (GPC) method using polystyrene as a standard curve.

[0073] In one embodiment of the present application, the surfactant of the present application can use a conventional surfactant known in the art, and can be, for example, an organofluorine-modified surfactant, a (poly)siloxane-based surfactant.

[0074] Suitable organic fluorine-modified surfactants of the present application are preferably compounds having a fluoroalkyl group or a fluoroalkylene group in at least one of the terminal, main chain and side chain, such as 1,1,2,2-tetrafluoro-n-octyl (1,1,2,2-tetrafluoro-n-propyl) ether, 1,1,2,2-tetrafluoro-n-octyl (n-hexyl) ether, hexaethylene glycol di(1,1,2,2,3,3-hexafluoro-n-pentyl) ether, octaethylene glycol di(1,1,2,2-tetrafluoro-n-butyl) ether, hexapropylene glycol di(1,1,2,2,2,3,3-hexafluoro-n-pentyl) ether, octapropylene glycol di(1,1,2,2-tetrafluoro-n-butyl) ether, sodium perfluoro-n-dodecane sulfonate, 1,1,2,2,3,3-hexafluoro-n-decane, 1,1,2,2,8,8,9,9,10,10-decafluoro-n-dodecane, and / or, sodium fluoroalkyl benzene sulfonate, sodium fluoroalkyl phosphate, sodium fluoroalkyl carboxylate, diglycerol tetra(fluoroalkyl polyoxyethylene ether), fluoroalkyl ammonium iodide, fluoroalkyl betaine, other fluoroalkyl polyoxyethylene ethers, perfluoroalkyl polyoxyethanols, perfluoroalkyl alkoxylates, fluoroalkyl carboxylate esters, and the like. Commercially available organic fluorine surfactants can be, for example, BM-1000, BM01100 available from BM CHEMIE; Megaface F142D, F172, F173, F183, F178, F191, F471, F476 available from Dainippon Ink and Chemicals Inc.; Surflon S-112, SC-102, SC-103, SC104 available from Asahi Glass; Eftop EF301, EF303, EF352 available from Shinnakajima Chemical; Ftergent FT-100, FT-110, FT-140A, FT-150, FTX-218, FTX-251 available from NEOS.

[0075] In one embodiment of the present application, commercially available as (poly)siloxane-based surfactants are, for example, Toray silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, DC-57, DC-190 available from Dow Corning Toray Silicone Co., Ltd.; silicone KP341 available from Shin-Etsu Chemical; BYK-310, 320, 322, 323, 330, 333, 377, 378, 3760 available from BYK.

[0076] In one embodiment of the present application, other suitable surfactants can be, for example, ammonium salts and organic amine salts of the following acids: alkyl diphenyl ether disulfonic acid, alkyl diphenyl ether sulfonic acid, alkyl benzene sulfonic acid, polyoxyethylene alkyl ether sulfuric acid, and alkyl sulfuric acid.

[0077] In a preferred embodiment of the present application, the surfactant is preferably an organic silicon surfactant, more preferably selected from the group consisting of BYK 300, 330 series.

[0078] The surfactant in the present application can be used alone or in combination of two or more, and the amount is 0.005 to 0.5% by weight; preferably 0.01 to 0.4% by weight, more preferably 0.05 to 0.4% by weight, based on the total weight of the resin composition.

[0079] In the present application, the adhesion aid is a component that improves the adhesion of the obtained cured film to the substrate. As the (D) adhesion aid, a functional silane coupling agent having a reactive functional group such as styrene, methacryl, methacryloyl, vinyl, isocyanate, oxirane, amino, ureido, etc. is preferred.

[0080] Suitable silane coupling agents that can be used in the present application are, for example, vinyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethane trimethoxysilane, 3-glycidylpropyltrimethoxysilane, 3-methacrylonitrile propyltrimethoxysilane, 3-methacrylonitrile propyltriethoxysilane, 3-3-ethoxysilyl-N-(1,3-dimethyl-butylidene)propylamino hydrolysis condensate, N-phenyl-3-aminopropyltrimethoxysilane, 3-urea propyltriethoxysilane, gamma-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, gamma-isocyanate propyltriethoxysilane, gamma-glycidoxypropyltrimethoxysilane, beta-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc.

[0081] In the present application, the adhesion aid (D) can be used alone or two or more thereof can be used in combination, and the amount is 0.01 to 20% by weight, preferably 0.1 to 15% by weight, more preferably 0.1 to 10% by weight, based on the total weight of the resin composition.

[0082] In the present application, since the alkali-soluble resin of the present application has a suitable acid value, average molecular weight and dispersibility, the dissolution rate of the resin composition in an aqueous alkaline solution can be controlled, and certain Tg characteristics (glass transition temperature) are ensured, so it can be used to control the shape and size of the profile undercut. Secondly, when the resin composition is applied as a bottom layer sacrificial layer of photoresist in photolithography, it has good storage stability because it does not contain photosensitive components and crosslinking active components. The hydroxyl and carboxyl groups contained in the resin have a certain affinity to the substrate, so the resin composition has a certain adhesion to the substrate, ensuring that the development will not be floated.

[0083] In another aspect of the present application, a method for forming a pattern of photoresist is provided, comprising the following steps:

[0084] (i) uniformly coating the above-mentioned alkali-soluble resin composition on a substrate to form a bottom sacrificial layer resist, preferably, the substrate is selected from the group consisting of a glass substrate, a silicon substrate, a sapphire substrate, a silicon carbide substrate, a compound semiconductor substrate,

[0085] (ii) baking the resist film obtained in (i) at a temperature of 90 to 2000C, preferably at a temperature of 110 to 1500C, to remove the solvent, and the thickness of the bottom sacrificial layer resist after baking is 0.1 to 8 μm, more preferably 0.1 to 6 μm,

[0086] (iii) uniformly coating a positive resist or a negative resist on the bottom sacrificial layer resist baked in (ii), preferably, pre-baking the positive or negative resist at a temperature of 90 to 1500C,

[0087] (iv) partially irradiating the resist formed in (iii) through a mask using a ray, preferably, the ray is selected from the group consisting of a g-ray, a h-ray, an i-ray, a KrF excimer laser, an ArF excimer laser, an extreme ultraviolet (EUV) ray, an electron beam ray, an ion beam ray, an x-ray, preferably, a ray comprising a g-ray, a h-ray and / or an i-ray,

[0088] (v) developing the resist film obtained in (iv) using a developing solution,

[0089] (vi) optionally baking the developed resist at a temperature of 120 to 1800C, preferably at a temperature of 120 to 1500C, to make the film more completely rigid.

[0090] wherein, if a positive resist is uniformly coated on the bottom sacrificial layer, i.e. a positive resist is coated in step (iii), the method of patterning the resist is carried out according to the above-mentioned steps (i) to (vi).

[0091] wherein, if a negative resist is uniformly coated on the bottom sacrificial layer, i.e. a negative resist is coated in step (iii), the following step is added after step (iv) and before step (v): baking the exposed resist film in step (iv) at a temperature of 90 to 1300C (Post Exposure Bake) to solidify the resist film layer in the exposed area.

[0092] In the method of patterning the resist according to the present application, the above-mentioned explanations regarding the alkali-soluble resin composition as the bottom sacrificial layer resist apply equally, and are not necessarily repeated here.

[0093] In a preferred embodiment of the present application, in step (i), a coating film is formed on a substrate using the resin composition of the present application. Specifically, a solution of the resin composition for curing film formation is applied to the surface of a substrate, and preferably pre-baking is performed to remove the solvent to form a coating film. Suitable substrates can be glass substrates, silicon substrates, sapphire substrates, silicon carbide substrates, compound semiconductor substrates, and substrates obtained by forming various metal thin films on the surfaces thereof.

[0094] As the application method, for example, a spray coating method, a roll coating method, a spin coating method, a slit coating method, a bar coater method, an inkjet method can be used. As the conditions of the above-mentioned pre-baking, adjustment can be made depending on the kind of each component, the use ratio, for example, baking on a contact type hot plate at 90°C to 150°C for 30 seconds to 10 minutes can be performed. The thickness of the adhesive film after pre-baking is 0.1 to 8 μm, preferably 0.1 μm to 6 μm, more preferably 0.1 μm to 4 μm.

[0095] In a preferred embodiment of the present application, in step (ii), the coating film in step (i) can be dried by heating. The heating method is not particularly limited, for example, heating can be performed using a heating device such as an oven and / or a hot plate. The heating temperature is preferably lower than 200°C. Since the heating temperature is low, the resin composition of the present application can be preferably used as a bottom sacrificial layer for a Lift-off double layer process for forming an electrode by depositing a metal on a glass substrate for Mini LED, a sapphire substrate, and a III-V group film layer of a compound semiconductor power device. The heating temperature is preferably 90°C to 200°C, further preferably 110°C to 150°C. The heating time can vary depending on the kind of the heating device, for example, in the case of heating treatment on a hot plate, the heating time is 1 to 40 minutes, preferably within 30 minutes, more preferably within 10 minutes; in the case of heating treatment in an oven, the heating time is 30 to 80 minutes, preferably 30 to 60 minutes. Thus, a bottom sacrificial release layer as a target can be formed on a substrate.

[0096] In a preferred embodiment of the present application, in step (iii), a positive photoresist or a negative photoresist is applied to the resin composition on which step (ii) is completed to form a coating film. Specifically, a photoresist which can form a pattern using a photosensitive property is applied to the bottom sacrificial layer, and preferably pre-baking is performed to remove the solvent to form a coating film.

[0097] As the coating method, for example, a spray coating method, a roll coating method, a spin coating method, a slit coating method, a doctor blade coating method, an inkjet method can be used. As the conditions of the above-mentioned pre-baking, they can be adjusted according to the kind of each component, the used ratio, for example, heating on a contact type hot plate at a temperature of 90 to 150°C for 30 seconds to 10 minutes can be used. The thickness of the coating film after the pre-baking is 0.1 to 8 μm, preferably 0.1 μm to 6 μm, more preferably 0.1 μm to 4 μm.

[0098] In a preferred embodiment of the present application, in step (iv), a part of the photosensitive dry film resist film in step (iii) is irradiated with a ray, specifically, the coating film formed in step (iii) is irradiated with a ray through a mask having a specific pattern. Preferably, the ray can be ultraviolet ray, deep ultraviolet ray (DUV ray), extreme ultraviolet ray (EUV ray, wavelength 13.5 nm), X-ray, charged particle ray.

[0099] As the above-mentioned ultraviolet ray, g ray (wavelength 436 nm), h ray, i ray (wavelength 365 nm) can be used. As the deep ultraviolet ray, for example, KrF (wavelength 248 nm) / ArF (wavelength 193 nm) excimer laser can be used. The charged particle ray can be, for example, electron beam ray (0.01 to 0.001 nm), ion beam ray. Among them, the ultraviolet ray is preferred, more preferably a ray containing g ray, h ray and / or i ray. The exposure amount of the ray is 0.1 J / m 2 to 10000 J / m 2 .

[0100] In a preferred embodiment of the present application, in step (v), the coating film irradiated with a ray in step (iv) is developed. Specifically, for the coating film irradiated with a ray in step (iv), the part irradiated with a ray is removed (positive photoresist) or the part not irradiated with a ray is removed (negative photoresist) by developing with a developer. Among them, a suitable developer which can be used in the present application is, for example, an aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, ammonia, ethylamine, n-propylamine, diethylamine, diethylaminoethanol, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo[5,4,0]-7-undecene, 1,5-diazabicyclo[4,3,0]-5-nonane and the like alkali (alkaline compound). In addition, an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol, ethanol and / or a surfactant to the above-mentioned aqueous solution of an alkali, or an aqueous alkali solution containing a small amount of various organic solvents which can dissolve the positive or negative photoresist and the resin composition of the present application can also be used as a developer.

[0101] In a preferred embodiment of the present application, the suitable developing method of the present application is, for example, a spin coating method, a dip coating method, a spin and dip coating method, a spray coating method. The developing time in the present application can be determined according to the dissolution rate of the resin composition of the present application in the developing solution, and can be, for example, 30 to 120 seconds.

[0102] In a preferred embodiment of the present application, after the photoresist is developed, the patterned coating film is preferably cleaned by a running water washing process.

[0103] In a preferred embodiment of the present application, the alkali dissolution rate of the bottom layer sacrificial layer photoresist during development is 5 to 250 nm / s, and the developing time is 30 to 180 seconds.

[0104] In a preferred embodiment of the present application, after the photoresist is developed, the undercut width of the bottom layer sacrificial layer relative to the upper layer photoresist is 0.1 to 6.0 μm, preferably 0.2 to 5.9 μm.

[0105] In a preferred embodiment of the present application, the undercut width can be set to different standards according to the thickness of the photoresist film, i.e. the undercut width can be adjusted as needed.

[0106] In a preferred embodiment of the present application, after the photoresist is developed, the ratio of the undercut width of the bottom layer sacrificial layer photoresist to the line width of the upper layer photoresist is 0.1 to 0.5:1, preferably 0.1 to 0.2:1.

[0107] In a preferred embodiment of the present application, when the line width of the upper layer photoresist is < 5 μm, the ratio of the undercut width of the bottom layer sacrificial layer photoresist to the line width of the upper layer photoresist is preferably less than 0.2:1, more preferably 0.13 to 0.17:1.

[0108] In a preferred embodiment of the present application, when the line width of the photoresist is > 10 μm, the ratio of the undercut width of the bottom layer sacrificial layer photoresist to the line width of the upper layer photoresist can be 0.1 to 0.5:1.

[0109] In a preferred embodiment of the present application, after the photoresist is developed, the ratio of the upper and lower undercut gap of the bottom layer sacrificial layer photoresist to the line width of the upper layer photoresist is less than 0.2:1.

[0110] In another aspect of the present application, the method of patterning the double layer photoresist is also applied to the application of patterning metal in the semiconductor field.

[0111] The resin composition of the present application and the positive / negative photoresist double-layer coating film are used in the process of manufacturing semiconductor elements. The resin composition of the present application is used as a bottom sacrificial release layer in the process of manufacturing metal electrodes in the process of manufacturing semiconductor elements. The semiconductor elements can be formed by using known methods. Since the semiconductor elements need to be processed using such materials, they can be preferably used in electronic devices such as display elements, LEDs, solar thin-film batteries, etc.

[0112] Advantageously, both positive photoresists and negative photoresists can be coated on the bottom sacrificial layer photoresist of the present application, and the application range is wide.

[0113] It should be noted that in the present specification, each feature, parameter, condition and combination thereof described for the alkali-soluble resin and its composition product and its application in the semiconductor metal patterning application are applicable to its preparation method and use.

[0114] The present application is further illustrated by the following examples, but the present application is not limited thereto.

[0115] Example

[0116] Raw materials used:

[0117] Methacrylic acid, purchased from Sartomer Company, USA

[0118] Methyl methacrylate, purchased from Sartomer Company, USA

[0119] Hydroxyethyl methacrylate, purchased from Mitsubishi Chemical Corporation, Japan

[0120] Azobisisobutyronitrile, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0121] Example 1

[0122] Preparation of alkali-soluble resin 1

[0123] 100 g of propylene glycol monomethyl ether (purchased from Dow Solvents Company, USA) was added to a four-necked flask equipped with a stirring device, a thermometer, a gas inlet tube, and a condenser tube. The flask was placed in a constant temperature oil bath and clamped with a stand. Nitrogen was introduced, the stirring was turned on, and the temperature was raised to 110°C.

[0124] A mixture of 10 g of methacrylic acid (purchased from Sartomer Company, USA), 76 g of methyl methacrylate (purchased from Sartomer Company, USA), 30 g of hydroxyethyl methacrylate (purchased from Mitsubishi Chemical, Japan), and 3 g of azobisisobutyronitrile (purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.) in 80 g of propylene glycol monomethyl ether (purchased from Dow Solvents, USA) was dissolved completely, and the solution was dropped into the above flask from a dropping funnel over 2 hours. After the dropping was completed, the reaction was carried out at a constant temperature of 110°C for 2 hours for polymerization, and finally the temperature was lowered to 50°C to pour out the polymerized material. It was detected that a resin solution containing hydroxyl groups having a weight average molecular weight of 15,000, a solid acid value of 59.7 KOH mg / g, a solid content of 40%, and a hydroxyl value of 107.5 KOH mg / g was obtained.

[0125] Preparation of alkali-soluble resin 2 to 5

[0126] Similar to the preparation of alkali-soluble resin 1, the preparation of alkali-soluble resin 2 to 5 was carried out, except that different monomers were used, and the types and amounts of the monomers used are shown in Table 1.

[0127] Table 1: Amounts of monomers and solvents used in preparation examples

[0128]

[0129] Preparation of resin composition 1

[0130] To a mixture of 100 parts by mass of the polymer solution of alkali-soluble resin 1 containing alkali-soluble resin (A), 1 part by weight of high-polymerized organosiloxane polymer (BYK-333 of BYK) as a surfactant (C), and 2 parts by weight of 3-glycidylpropyltrimethoxysilane (KBM-403 of Shin-Etsu Chemical) as a adhesion aid (D), as a solvent, propylene glycol monomethyl ether was added in an amount of 20% of the solid content of the alkali-soluble resin, and then filtered with a membrane filter having a pore size of 0.1 μm, thereby preparing resin composition 1.

[0131] Resin compositions 2 and 3 were prepared in the same manner and proportions, except that alkali-soluble resins 2 and 3 in Table 1 were used, respectively.

[0132] Photolithography development

[0133] The resin composition 1 was spin-coated on a single crystal silicon substrate to form a coating film. Then, the coating film was pre-baked at 115°C for 180 seconds to form a resist film with a thickness of about 1.0 μm. Subsequently, a positive photosensitive resin composition was spin-coated on the formed resist film to form a photoresist coating film. The coating film was then pre-baked at 100°C for 90 seconds to finally form a photoresist film with a thickness of 3.5 μm. Then, the photoresist film was patterned and exposed to ultraviolet light at 120 mJ / cm 2 using a line and space mask. Next, the substrate with the exposed photoresist film was developed at a temperature of 23°C using a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) for 60 seconds, and then rinsed with ultrapure water for 1 minute.

[0134] Test

[0135] Molecular weight determination: According to GB / T 21863-2008, the molecular weight of the polymer resin in the present application was determined by gel permeation chromatography (GPC) method using polystyrene as a standard curve,

[0136] Solid content determination: According to GB / T 7193-2008,

[0137] Acid value: According to GB / T 2895-2008,

[0138] Hydroxyl value: According to DIN 53240-2:2007-11.

[0139] Alkali dissolution rate determination

[0140] After exposure, the alkali dissolution rate of the bottom sacrificial layer was determined, the development time of the example was recorded, the undercut window width was observed by microscope, and the alkali dissolution rate was calculated by the following formula

[0141]

[0142] wherein,

[0143] The thickness of the bottom sacrificial layer resist film was obtained by an optical film thickness meter, Nikon Filmetrics F20,

[0144] The apparent development time of the bottom sacrificial layer resist film was obtained by a stopwatch timer.

[0145] Development adhesion test

[0146] The photoresist after development in the photoetching development step was washed with ultrapure water for 1 minute, and then the line and space pattern with a width of 10 μm was observed under a microscope to determine whether peeling occurred, which was an index of development adhesion. At this time, the degree of peeling was rated as A: no peeling, B: slight peeling, C: partial peeling, and D: complete peeling, and the development adhesion was rated as good in the case of A or B and as poor in the case of C or D.

[0147] Observation of Inverted Trapezoidal Cross-Sectional Shape

[0148] The photoresist after development in the photoetching development step was washed with ultrapure water for 1 minute, and then the inverted trapezoidal cross-sectional shape formed was observed under a microscope to determine the undercut width and the difference between the upper and lower bottoms of the lower layer photoresist, which were indices of the inverted trapezoidal cross-sectional shape. The specific evaluation criteria were as follows:

[0149] When the undercut width was ≥ 1 μm and the difference between the upper and lower bottoms of the lower layer photoresist was ≤ 20% of the line width of the upper layer photoresist, the result was rated as good.

[0150] Storage Stability Test

[0151] The resin compositions 1 to 3 were respectively stored in a dust-free room at room temperature (temperature: 23 ± 0.5 °C, humidity: 45 ± 5%) for 3 months, and the viscosity before and after storage was measured to calculate the viscosity change rate (%) which was an index of storage stability. The viscosity change rate was rated as follows: [a] viscosity change rate < 5%, [b] viscosity change rate ≥ 5% but < 10%, [c] viscosity change rate ≥ 10% but < 15%, and [d] viscosity change rate ≥ 15%. In the case of [a] or [b], the storage stability was rated as good (s); in the case of [c] or [d], the storage stability was rated as poor (n). For viscosity measurement, a constant capillary viscometer (Shanghai Huichuang Glass Products Co., Ltd.) was used to measure in a 25 °C constant temperature water bath.

[0152] It should be noted that the coating film using the resin composition 1 was Example 1, the photoetching coating film using the resin composition 2 was Example 2, and the coating film using the resin composition 3 was Example 3.

[0153] Comparative Example 1

[0154] In the comparative example, only a negative photoresist (photoresist type KMP-3130, purchased from Beijing Kohway Microelectronic Material Co., Ltd.) was used without using a bottom layer sacrificial layer resin composition, the pre-baking temperature of the negative photoresist was 100 °C, the time was 90 seconds, and development was performed in a 2.38% TMAH aqueous solution for 60 seconds.

[0155] Table 2 Test Results

[0156]

[0157]

[0158] Evaluation of developing adhesion: A represents no peeling, B represents slightly peeling, C represents partial peeling, and D represents whole surface peeling.

[0159] s represents storage stability, and n represents storage instability.

[0160] Table 3: Measurement results of the alkali dissolution rate of the bottom sacrificial layer resist after exposure of Example 1 and Example 2

[0161]

[0162] 1) The first pre-baking temperature, i.e. the temperature at which the resist film is pre-baked after coating the bottom sacrificial layer;

[0163] 2) The second pre-baking temperature, i.e. the temperature at which the resist film is pre-baked after coating the upper layer of resist.

[0164] The first pre-baking time and the second pre-baking time are each 180 seconds.

[0165] From Table 3, it can be seen that the average alkali dissolution rate of the bottom sacrificial layer resist after exposure is affected by the resin composition, the first pre-baking temperature, and the second pre-baking temperature, and more specifically, the average alkali dissolution rate of the bottom sacrificial layer resist after exposure is affected by the molecular weight of the alkali soluble resin, the solid acid value, the first pre-baking temperature, and the second pre-baking temperature.

[0166] Table 4: Change in photosensitivity of Comparative Example 1 stored for 3 months

[0167] Days on shelf ΔEOP (%) 1 0.00 8 0.00 17 16.78 22 16.78 37 20.98 51 36.99 105 53.15

[0168] ΔEOP (%) represents the relative change rate of the optimum exposure amount under the current process conditions.

[0169] Table 5: Relative change rate of the optimum exposure amount in the Dense Lines / Spaces region of the target line width

[0170]

[0171] The target line width is the Dense Lines / Spaces region, which is a line region with a line width of 1:1, and the pattern is relatively dense, and is used to analyze the resolution of the resist. After development, the resist itself is a line, and the remaining most of the area has no resist. EOP represents the optimum exposure amount under the current process conditions

[0172] Process condition: soft bake 100°C 90 seconds, film thickness 3.5 μm, i-line exposure, post exposure bake (PEB) 90 seconds, development in 2.38% TMAH aqueous solution for 60 seconds.

[0173] Wherein, the best exposure amount at PEB temperature 110°C is the baseline. The increase is represented by a + value, and the decrease is represented by a - value.

[0174] Table 6. Relative change rate of the best exposure amount at ISO Trench 2.5 μm position

[0175]

[0176] The target is ISO Trench 2.5 μm position, which has a large area of photoresist after the photoresist is developed, and a small part of the position forms a line groove (the position of the line groove has no photoresist). EOP represents the best exposure amount under the current process condition

[0177] Process condition: soft bake 100°C 90 seconds, film thickness 3.5 μm, i-line exposure, post exposure bake (PEB) 90 seconds, development in 2.38% TMAH aqueous solution for 60 seconds.

[0178] Wherein, the best exposure amount at PEB temperature 110°C is the baseline. The increase is represented by a + value, and the decrease is represented by a - value.

[0179] The alkali dissolution rate of the bottom sacrificial layer photoresist of the present application can be adjusted within a certain range, so that the appropriate development time can be controlled to achieve the appropriate undercut width, thereby meeting different customer requirements.

[0180] As can be seen in Table 4, the photosensitivity of the photoresist film of Comparative Example 1 is easily affected by the baking temperature after the film is coated, that is, even if the temperature difference is only 10°C from 105°C to 115°C, the change in the best exposure amount can be up to 190%, which brings great challenges to the temperature control of the photoetching process, and the accuracy of the photoetching instrument and the operation requirements of the operator are extremely high.

[0181] Figure 1 A schematic diagram of the undercut window of the bottom sacrificial layer photoresist relative to the upper photoresist is shown, wherein the undercut window is a reverse trapezoidal structure, wherein a is the undercut width, b is the distance between the upper and lower bottoms of the bottom sacrificial layer after the photoresist is developed (i.e., the undercut height), 11 is a substrate / substrate, 12 is a bottom sacrificial layer photoresist, and 13 is an upper positive / negative photoresist.

Claims

1. A resin composition comprising the following components: (A) an alkali-soluble resin, 10 to 30% by weight; (B) a solvent, 70 to 90% by weight; (C) a surfactant, 0.005 to 0.5% by weight; (D) an adhesion aid, 0.01 to 20% by weight, based on the total weight of the resin composition, and the sum of each component is 100% by weight, wherein the resin composition does not contain a photosensitive component, wherein the weight average molecular weight of the alkali-soluble resin (A) is 1,000 to 100,000, and the distribution width of the molecular weight is 1 to 5, wherein the acid value of the alkali-soluble resin is 10 to 300 mg KOH / g, wherein the weight average molecular weight is determined according to GB / T 21863-2008, wherein the acid value is determined according to GB / T 2895-2008.

2. The resin composition according to claim 1, wherein the amount of the solvent (B) is 75 to 85% by weight.

3. The resin composition according to claim 1, wherein the amount of the surfactant (C) is 0.01 to 0.4% by weight.

4. The resin composition according to claim 3, wherein the amount of the surfactant (C) is 0.05 to 0.4% by weight.

5. The resin composition according to claim 1, wherein the amount of the adhesion aid (D) is 0.1 to 15% by weight.

6. The resin composition according to claim 5, wherein the amount of the adhesion aid (D) is 0.1 to 10% by weight.

7. The resin composition according to any one of claims 1 to 3, wherein the weight average molecular weight of the alkali-soluble resin is 3,000 to 50,000, and the distribution width of the molecular weight is 1 to 3.

8. The resin composition according to claim 7, wherein the distribution width of the molecular weight of the alkali-soluble resin is 1.5-2.

5.

9. The resin composition according to any one of claims 1 to 3, wherein the acid value of the alkali-soluble resin is 20 to 200 mg KOH / g.

10. The resin composition according to claim 9, wherein the acid value of the alkali-soluble resin is 30 to 100 mg KOH / g.

11. The resin composition according to any one of claims 1 to 3, wherein the hydroxyl value of the alkali-soluble resin is 50 to 300 mg KOH / g, the hydroxyl value being determined according to DIN 53240-2:2007-11.

12. The resin composition according to any one of claims 1 to 3, wherein the alkali-soluble resin is selected from the group consisting of novolak resins, hydroxystyrene-based resins, acrylic or methacrylic acid-based resins.

13. The resin composition according to claim 12, wherein the alkali-soluble resin is selected from the group consisting of acrylic or methacrylic acid resins.

14. The resin composition according to claim 13, wherein the acrylic or methacrylic acid resin is prepared by copolymerization of at least three monomers from the group consisting of methacrylic acid, methyl methacrylate, cyclohexyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, and hydroxypropyl acrylate monomers.

15. The resin composition according to claim 14, wherein the acrylic or methacrylic resin is prepared by copolymerization of methacrylic acid, methyl methacrylate and one selected from the group consisting of hydroxyethyl methacrylate, hydroxypropyl methacrylate.

16. The resin composition according to claim 15, wherein the weight ratio of the monomers methacrylic acid, methyl methacrylate, hydroxyethyl methacrylate is from 1.0:10.0:5.0 to 1.0:2.5:1.

5.

17. The resin composition according to claim 16, wherein the weight ratio of the monomers methacrylic acid, methyl methacrylate, hydroxyethyl methacrylate is from 1.0:7.6:3.0 to 1.0:4.3:1.

88.

18. The resin composition according to any one of claims 1 to 3, wherein the solvent is one or a mixture of two or more selected from the group consisting of propylene glycol monoalkyl ether, propylene glycol monoalkyl ether acetate, alkyl lactate and gamma-butyrolactone.

19. The resin composition according to claim 18, wherein the solvent is propylene glycol monomethyl ether.

20. A method for forming a pattern of a photoresist, comprising the steps of, (i) uniformly coating a resin composition according to any one of claims 1 to 19 on a substrate to form a bottom sacrificial layer photoresist; (ii) baking the photoresist film obtained in (i) at a temperature of 90 to 200°C to remove the solvent, and the thickness of the bottom sacrificial layer photoresist after baking is from 0.1 to 8 μm; (iii) uniformly coating a photoresist, which is a positive photoresist or a negative photoresist, on the bottom sacrificial layer photoresist baked in (ii); (iv) partially irradiating the photoresist formed in (iv) with a ray through a mask; (v) developing the photoresist film obtained in (v) with a developer; (vi) optionally baking the developed photoresist at 120 to 180°C to make the film hard more completely.

21. The method for forming a pattern of a photoresist according to claim 20, wherein in step (ii), the photoresist film obtained in (i) is baked at a temperature of 110 to 150°C to remove the solvent.

22. The method for forming a pattern of a photoresist according to claim 20, wherein in step (ii), the thickness of the bottom sacrificial layer photoresist after baking is from 0.1 to 6 μm.

23. The method for forming a pattern of a photoresist according to claim 20, wherein in step (iii), the positive or negative photoresist is pre-baked at a temperature of 90 to 150°C.

24. The method for forming a pattern of a photoresist according to claim 20, wherein in step (vi), the developed photoresist is optionally baked at 120 to 150°C to make the film hard more completely.

25. The method of patterning photoresist according to any one of claims 20-24, wherein, If the positive photoresist is uniformly coated on the bottom sacrificial layer, i.e. the positive photoresist is coated in step (iii), the method of patterning the photoresist is carried out according to steps (i) to (vi) as described above; wherein if the negative photoresist is uniformly coated on the bottom sacrificial layer, i.e. the negative photoresist is coated in step (iii), the following step is added after step (iv) before step (v): the photoresist film after exposure in step (iv) is subjected to post-exposure baking at a temperature of 90 to 130°C to solidify the photoresist film layer in the exposed area.

26. The method of patterning a photoresist according to any one of claims 20-24, wherein The alkali dissolution rate of the bottom sacrificial layer during development is 5 to 250 nm / s, and the development time is 30 to 180 seconds.

27. The method of patterning a photoresist according to any one of claims 20-24, wherein The undercut width of the bottom sacrificial layer relative to the upper layer of photoresist is 0.1 to 6.0 μm.

28. The method of patterning a photoresist according to claim 27, wherein The undercut width of the bottom sacrificial layer relative to the upper layer of photoresist is 0.2 to 5.9 μm.

29. The method of patterning a photoresist according to any one of claims 20-24, wherein The ratio of the undercut width of the bottom sacrificial layer photoresist after development to the line width of the upper layer of photoresist is 0.1-0.5:

1.

30. The method of patterning a photoresist according to claim 29, wherein The ratio of the undercut width of the bottom sacrificial layer photoresist after development to the line width of the upper layer of photoresist is 0.1-0.2:

1.

31. The method of patterning a photoresist according to claim 30, wherein The ratio of the undercut width of the bottom sacrificial layer photoresist after development to the line width of the upper layer of photoresist is 0.13-0.17:

1.

32. The method of patterning a photoresist according to any one of claims 20-24, wherein The ratio of the undercut width of the bottom sacrificial layer photoresist after development to the line width of the upper layer of photoresist is less than 0.2:

1.

33. Use of the method of patterning a photoresist according to any one of claims 20 to 32 for the patterning of metals in semiconductor production.

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