Photoresist additive and photoresist composition

Abstract

The photoresist additive and the photoresist composition provided by the invention can improve the film coating performance of a high-viscosity photoresist and a thick-film photoresist, and have a special effect in the aspect of improving the oxygen-containing plasma etching resistance of the photoresist, and the additive is a polymer of which a main chain or a branch chain comprises structural fragments as shown in a formula (1) and a formula (2), at least one fluorine atom is contained in the # imgabs0 # R1-R4, and at least one of the R1-R4 is a nitrogen-containing heteroaryl group of C3-C30; the molecular weight Mw of the polymer is 3000-23000, the sum of m in the structural segments of the formula (1) is 5-20, and the sum of n in the structural segments of the formula (2) is 7-30.

Description

Technical Field

[0001] The invention relates to a photoresist additive which can be used as a photoresist leveling agent. The invention also relates to a photoresist composition. Background Art

[0002] Positive photoresist is used for graphic and planarization layers in panel TFT processes and semiconductor processes. As a key material, it determines the yield of the process. With the continuous improvement of circuit refinement, the process technology has higher and higher requirements for the uniformity of photoresist coating. Traditional technology has a certain effect on improving the performance of coating by adding leveling agents, plasticizers, high boiling point solvents and other technical means, but it is not effective when applied to high viscosity photoresists and thick film photoresists, and often has problems such as uneven coating, thick edges, and Mura. Taking traditional leveling agents as an example, its principle is to achieve the effect of coating by reducing the surface tension of the solvent to improve the wettability with the substrate. Its ability to drive the migration of macromolecular resins is poor. In order to prevent the occurrence of coating problems such as shrinkage cavities and shrinkage edges, traditional technology often improves the above problems by increasing the amount of leveling agents used. However, the increase in the amount of leveling agents used will bring about negative effects such as decreased film thickness uniformity and decreased fluidity. Therefore, it is urgent to research and develop new photoresist additives. Summary of the invention

[0003] After in-depth research, the inventor has refined the design of the leveling agent component in the photoresist, and is committed to using polymer components to achieve a leveling effect, improve the photoresist coating effect, and develop an additive for positive photoresist. The additive can drive the migration of resin molecules to achieve the purpose of improving the coating performance, and can take into account the improvement of the uniformity of the photoresist coating and the wettability of the photoresist and the substrate, especially for high-viscosity photoresist and thick-film photoresist. There is an excellent effect. In addition to improving the coating performance, it has been studied that the additive of the present invention also has a special technical effect in improving the resistance of photoresist to oxygen-containing plasma etching. More specifically, the additive provided by the present invention can improve the coating performance of high-viscosity photoresist and thick-film photoresist, and has a special effect in improving the resistance of photoresist to oxygen-containing plasma etching.

[0004] In order to achieve the above object, the present invention provides a photoresist additive, wherein the additive has a polymer having structural fragments of the following formula (1) and formula (2) in the main chain or the side chain,

[0005]

[0006] R 1 , R 2 , R 3 , R 4are each independently H, F, Si, a C1-C10 aliphatic hydrocarbon group or a fluorinated aliphatic hydrocarbon group, a C6-C30 aryl group or a fluorinated C6-C30 aryl group, a C3-C30 heteroaryl group or a fluorinated C3-C30 heteroaryl group, wherein the heteroatom in the heteroaryl group or the fluorinated heteroaryl group is a nitrogen atom, provided that: R 1 -R 4 There is at least one fluorine atom in R 1 -R 4 At least one of the structural fragments of formula (1) is a nitrogen-containing heteroaryl group of C3-C30; the molecular weight Mw of the polymer is 3000-23000, the sum of m in all structural fragments of formula (1) is 5-20, and the sum of n in all structural fragments of formula (2) is 7-30.

[0007] It should be noted that, unless otherwise defined below, the meanings of all technical terms and scientific terms used herein are intended to be the same as those commonly understood by those skilled in the art. Reference to the technology used herein is intended to refer to the technology commonly understood in the art, including those changes in technology that are obvious to those skilled in the art or replacement of equivalent technology. Although it is believed that the following terms are well understood by those skilled in the art, the following definitions are still set forth to better explain the present invention.

[0008] In this specification, the expression of Ca to Cb indicates that the number of carbon atoms in the group is a to b. Unless otherwise specified, the number of carbon atoms generally does not include the number of carbon atoms in the substituent. When describing C1 to C30, it includes but is not limited to C1, C2, C3, C4, C3, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C22, C24, C26, C28, etc., and other numerical ranges are not repeated.

[0009] The terms "comprises," "comprising," "having," "containing," or "involving" and other variations thereof herein are inclusive or open-ended and do not exclude additional unrecited elements or method steps.

[0010] In the present invention, the expression of chemical elements, unless otherwise specified, generally includes the concept of isotopes with the same chemical properties. For example, the expression "hydrogen" also includes the concepts of "deuterium" and "tritium" with the same chemical properties, and carbon (C) includes 12 C. 13 C, etc., no further details.

[0011] As used herein, the terms "(sub)aryl" and "aromatic ring" refer to an all-carbon monocyclic or fused-ring polycyclic aromatic group having a conjugated π electron system. As used herein, the terms "(sub)heteroaryl" and "heteroaromatic ring" refer to a monocyclic, bicyclic or tricyclic aromatic ring system. The aryl and heteroaryl groups are as defined herein. If not otherwise specified, aromaticity or heteroaromaticity refers to aromatic groups that satisfy the π conjugated system, including both monocyclic and fused ring residues.

[0012] In the present specification, the substituted or unsubstituted C6-C60 aromatic group is preferably a C6-C30 aromatic group, and more preferably a group selected from the group consisting of phenyl, naphthyl, anthracenyl, benzanthryl, phenanthryl, triphenylenyl, pyrene, chrysene, peryl, fluoranthene, naphthyl, pentacene, benzopyrene, biphenyl, isophenyl, terphenyl, triphenyl, tetraphenyl, fluorenyl, spirobifluorenyl, dihydrophenanthryl, dihydropyrenyl, tetrahydropyrenyl, cis- or trans-indenofluorenyl, trimerized indenyl, isotrimerized indenyl, spirotrimerized indenyl, and spiroisotrimerized indenyl. Specifically, the biphenyl group is selected from 2-biphenyl, 3-biphenyl and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl and m-terphenyl-2-yl; the naphthyl group includes 1-naphthyl or 2-naphthyl; the anthracenyl group is selected from 1-anthracenyl, 2-anthracenyl and 9-anthracenyl; the fluorenyl group is selected from 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl and 9-fluorenyl; the pyrenyl group is selected from 1-pyrenyl, 2-pyrenyl and 4-pyrenyl; the tetraphenyl group is selected from 1-tetraphenyl, 2-tetraphenyl and 9-tetraphenyl. Preferred examples of the aryl group in the present invention include phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, indenyl, fluorenyl and its derivatives, fluoranthenyl, triphenylene, pyrenyl, peryl, The biphenyl group is selected from the group consisting of 2-biphenyl, 3-biphenyl and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl and m-terphenyl-2-yl; the naphthyl group includes 1-naphthyl or 2-naphthyl; the anthracenyl group is selected from the group consisting of 1-anthracenyl, 2-anthracenyl and 9-anthracenyl. The fluorenyl group is selected from the group consisting of 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl and 9-fluorenyl; the fluorenyl derivative is selected from the group consisting of 9,9-dimethylfluorene, 9,9-spirobifluorene and benzofluorene; the pyrenyl group is selected from the group consisting of 1-pyrenyl, 2-pyrenyl and 4-pyrenyl; the naphthyl group is selected from the group consisting of 1-naphthyl, 2-naphthyl and 9-naphthyl. The C6-C60 aryl group of the present invention can also be a group formed by combining the above groups by single bond connection or / and fusion.

[0013] In the present specification, the substituted or unsubstituted C3-C60 heteroaryl group is preferably a C3-C30 heteroaryl group, more preferably a nitrogen-containing heteroaryl group, an oxygen-containing heteroaryl group, a sulfur-containing heteroaryl group, etc. Specific examples include: furyl, thienyl, pyrrolyl, pyridyl, benzofuranyl, benzothienyl, isobenzofuranyl, isobenzothienyl, indolyl, isoindolyl, dibenzofuranyl, dibenzothienyl, carbazolyl and its derivatives, quinolyl, isoquinolyl, acridinyl, phenanthridine yl, benzo-5,6-quinolyl, benzo-6,7-quinolyl, benzo-7,8-quinolyl, phenothiazinyl, phenazinyl, pyrazolyl, indazolyl, imidazolyl, benzimidazolyl, naphthoimidazolyl, phenanthroimidazolyl, pyridoimidazolyl, pyrazinoimidazolyl, quinoxalinoimidazolyl, oxazolyl, benzoxazolyl, naphthoxazolyl, anthrazolyl, phenanthroxazolyl, 1,2-thiazolyl, 1,3-thiazolyl, benzothiazolyl, pyridazinyl, benzopyridazinyl, pyrimidazinyl, pyridinyl, benzopyrimidinyl, quinoxalinyl, 1,5-diazaanthryl, 2,7-diazapyrenyl, 2,3-diazapyrenyl, 1,6-diazapyrenyl, 1,8-diazapyrenyl, 4,5-diazapyrenyl, 4,5,9,10-tetraazaperyl, pyrazinyl, phenazinyl, phenothiazinyl, naphthyridinyl, azacarbazolyl, benzocarbolinyl, phenanthrolinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, benzotriazolyl, 1,2,3-oxadiazolyl, oxadiazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazolyl, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purinyl, pteridinyl, indolizine, benzothiadiazole and the like. Preferred examples of heteroaryl groups in the present invention include furanyl, thienyl, pyrrolyl, benzofuranyl, benzothienyl, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothienyl, carbazolyl and derivatives thereof, wherein the carbazolyl derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazolebenzocarbazole, dibenzocarbazole or indolecarbazole. The C3-C60 heteroaryl group of the present invention may also be a group formed by combining the above groups by single bond connection or / and fusion.

[0014] If substituents are described as being "independently selected" from a group, each substituent is selected independently of the other. Thus, each substituent may be the same as or different from another (other) substituent.

[0015] As used herein, the term "one or more" means 1 or more than 1, such as 2, 3, 4, 5 or 10, where reasonable.

[0016] Unless otherwise indicated, as used herein, the point of attachment of a substituent may be from any suitable position of the substituent.

[0017] When a bond to a substituent is shown to pass through a bond connecting two atoms in a ring, then such substituent may be bonded to any ring atom in the substitutable ring.

[0018] The term "about" means within ±10% of the stated numerical value, preferably within ±5%, more preferably within ±2%.

[0019] In the structural formula disclosed in this specification, the expression of the ring structure crossed by “—” indicates that the connection site is any position on the ring structure that can form a bond.

[0020] In the present invention, the aliphatic hydrocarbon group refers to a non-directional group formed by C and H elements, generally including alkyl, alkenyl, olefinic group, etc., and can be chain or cyclic.

[0021] As a more specific example, in this specification, chain alkyl includes the concept of both straight chain and branched chain alkyl. Examples of C1-C10 chain alkyl include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, neopentyl, n-hexyl neohexyl, n-heptyl, n-octyl, 2-ethylhexyl, etc. Examples of C1-C20 chain haloalkyl include: trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, etc. In this specification, cycloalkyl includes monocyclic alkyl and polycyclic alkyl, and specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantyl, etc.

[0022] The alkenyl group that can be used in the present invention includes both straight-chain and branched alkenyl groups, and the number of carbon atoms of the alkenyl group is preferably 2 to 10. Specific examples include vinyl, 1-propenyl, 2-propenyl, 2-butenyl, 3-butenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 5-hexenyl, 7-octenyl, and groups in which these groups have substituents such as alkyl and alkoxy groups.

[0023] The alkynyl group that can be used in the present invention includes both straight-chain and branched alkenyl groups, and the number of carbon atoms of the alkynyl group is preferably 2 to 10. Specific examples of the alkynyl group include ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, 3-butynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 5-hexynyl, and groups in which these groups have substituents such as alkyl and alkoxy groups.

[0024] It should be noted that the above-mentioned additive structure is a copolymer structure, which can be in the form of random, alternating, block or other copolymers. 1 -R 4If , m, and n meet the above limitations, the technical effects of the present invention can be achieved.

[0025] The general formula of the present invention is a fluorine-containing polymer. The presence of fluorine can significantly reduce the surface tension of the photoresist, which is beneficial to the spreadability of the coating and improves the wettability of the photoresist and the substrate. At the same time, the polymer also contains a nitrogen heterocyclic group, which drives the migration of macromolecules by combining with resin molecules to effectively improve the uniformity of the photoresist coating, especially the coating performance of high-viscosity photoresists. The nitrogen heterocyclic group can also improve the etching resistance of the photoresist to oxygen-containing plasma by combining with resin molecules.

[0026] In the above general formula of the present invention, the molecular weight of the additive is 3000-23000, for example, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 11000, 12000, 13000, 14000, 15000, 16000, 17000, 18000, 19000, 20000, 21000, 22000, 23000, preferably 4000 to 13000. If the molecular weight is too high, the compatibility with the photoresist system is poor, and if the molecular weight is too low, no beneficial effect is achieved.

[0027] In a preferred embodiment of the present invention, the polymer is a polymer composed of structural fragments of formula (1) and formula (2), and its molecular weight is 4000-13000, and the sum of m in all structural fragments of formula (1) is 8-20, for example, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20. The sum of n in all structural fragments of formula (2) is 10-30, for example, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30. The molecular weight distribution is 1.2-1.8, for example, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8.

[0028] In a preferred embodiment of the present invention, R 1 -R 4 Each is independently selected from the following groups:

[0029] Hydrogen, methyl, ethyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl, 2-hydroxyethyl, decyl, sulfonic acid methyl, phenyl, isobornyl, trifluoromethyl, hexafluoropropyl, imidazolyl, pyridyl, quinolyl, naphthyl, anthracenyl, benzanthryl, phenanthryl, triphenylenyl, pyrenyl, fluoranthenyl, biphenyl, phenylene, terphenyl, triphenylene, fluorenyl.

[0030] In a preferred embodiment of the present invention, R1 -R 4 Each is independently selected from the following groups:

[0031]

[0032]

[0033] In a further preferred embodiment of the present invention, R 1 -R 4 At least one of the groups is a group having an imidazole structure, and it is further preferred that the group having an imidazole structure is a group selected from the above structures.

[0034] Another aspect of the present invention further provides a photoresist composition, which comprises an alkali-soluble resin, a photosensitizer, a cross-linking agent, a solvent, and the additive provided by the present invention.

[0035] In the above-mentioned photoresist composition of the present invention, the photosensitizer is a diazonaphthoquinone type photosensitizer well known to those skilled in the art, for example, it can be a diazonaphthoquinone sulfonyl chloride and a disubstituted ester compound of trihydroxybenzophenone, a diazonaphthoquinone sulfonyl chloride and a trisubstituted ester compound of tetrahydroxybenzophenone, or a diazonaphthoquinone sulfonyl chloride and α,α,α'-tri(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene disubstituted ester compound, etc.

[0036] Optionally, the alkali-soluble resin is a linear phenolic resin, which is polymerized with phenolic compounds and aldehyde compounds as raw materials. The phenolic compounds that can be cited include phenol, cresol, xylenol, ethylphenol, propylphenol, propylphenol, butylphenol, tert-butylphenol, di-tert-butylphenol, octylphenol, fluorophenol, chlorophenol, bromophenol, iodophenol, naphthol, anthracenol, dihydroxybenzene, dihydroxynaphthalene, biphenol, bisphenol, aminophenol, nitrophenol, phloroglucinol, etc. Aldehyde compounds can select one or more of formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, hexanal, trichloroacetaldehyde, furfural, glyoxal, allyl aldehyde, benzaldehyde, crotonaldehyde, o-tolualdehyde, salicylaldehyde, etc. More specifically, it may be a linear phenolic resin polymerized from cresol and formaldehyde, a linear phenolic resin polymerized from xylenol and formaldehyde, a linear phenolic resin polymerized from di-tert-butylphenol and formaldehyde, a linear phenolic resin polymerized from dihydroxynaphthalene and formaldehyde, a linear phenolic resin polymerized from phloroglucinol and formaldehyde, a linear phenolic resin polymerized from xylenol and formaldehyde and salicylaldehyde, and the like.

[0037] The alkali-soluble resin may also be a polyamic acid resin, which is polymerized from diamines and dianhydrides as raw materials. Examples of diamines include trans-1,4-cyclohexanediamine, p-phenylenediamine, m-phenylenediamine, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 3,4'-diaminodiphenyl ether, 2,2'-bis(trifluoromethyl)benzidine, 3,3'-bis(trifluoromethyl)benzidine, etc. Examples of dianhydrides include pyromellitic acid dianhydride, 1,6-difluoropyromellitic acid dianhydride, 1,6-bis(trifluoromethyl)pyromellitic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, etc., but are not limited thereto.

[0038] In the above-mentioned photoresist composition of the present invention, the crosslinking agent is well known to those skilled in the art, including amino crosslinking agents, epoxy crosslinking agents, ether crosslinking agents, urea crosslinking agents, etc. Specifically, it can include hexamethylenetetramine, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 1,4-butanediol diglycidyl ether, hexamethoxymethylmelamine, trialkoxycarbonylaminotriazine 1,3-bis(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone, etc.

[0039] In the above-mentioned photoresist composition of the present invention, the solvent is well known to those skilled in the art, and can be, for example, selected from one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol butyl methyl ether, diethylene glycol butyl ethyl ether, diethylene glycol diethyl ether ethyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol butyl methyl ether, dipropylene glycol ethylhexyl ether, triethylene glycol dimethyl ether, triethylene glycol tert-butyl ether, chloroform, xylene, ethyl lactate, γ-butyrolactone, N-methylpyrrolidone, benzyl alcohol, and dimethyl sulfoxide.

[0040] In the above-mentioned photoresist composition of the present invention, in order to improve the comprehensive performance of the photoresist composition, some auxiliary agents can be selected, for example, one or more selected from defoamers, coupling agents, and ultraviolet absorbers. Specifically, the types and amounts of auxiliary agents well known to those skilled in the art can be selected, and the defoamer can be selected from silicone defoamers, polyether defoamers, and polyether-modified polysiloxane defoamers. The coupling agent can be selected from trimethoxysilylbenzoic acid, vinyltrimethoxysilane, vinyltriacetoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-glycidylpropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc. The ultraviolet absorber can be selected from 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, phenyl o-hydroxybenzoate, 2,4-dihydroxybenzophenone, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine and the like.

[0041] Those skilled in the art can adjust the proportion of each component in the photoresist composition as needed. Taking the total weight of the photoresist composition as 100%, the weight content of each component in the photoresist composition is:

[0042]

[0043] The balance is solvent and other additives.

[0044] A further preferred ratio can be

[0045]

[0046] The additive and photoresist composition provided by the present invention are used in the display panel TFT array process and semiconductor packaging field. Other features and advantages of the present invention will be described in detail in the subsequent specific implementation section. DETAILED DESCRIPTION

[0047] The technical scheme of the present invention is further illustrated by specific embodiments below. Those skilled in the art should understand that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention. Unless otherwise specified, in the following examples and comparative examples, temperatures are degrees Celsius and parts and percentages are by weight.

[0048] Preparation Example 1

[0049] Imidazole ethyl methacrylate and hydroxybutyl methacrylate are copolymerized in a molar ratio of 2:3. The synthesis method is as follows: 200g of butyl acetate and 1.85g of azobisisobutyronitrile are added to a reaction flask and stirred at room temperature to dissolve. Then 32.4g of imidazole ethyl methacrylate and 42.7g of hydroxybutyl methacrylate are added, stirred and heated to 110°C and reacted for 3h, and then 2.7g of dodecanethiol is added to continue the reaction for 30min, cooled to room temperature, and the polymer is precipitated with 110g of methanol and vacuum dried at 90°C for 3h to obtain additive A powder, with a weight average molecular weight (determined by gel permeation chromatography) Mw=7900 and a molecular weight distribution of 1.36.

[0050]

[0051] Preparation Example 2

[0052] Imidazole tetrafluoroethyl methacrylate and hydroxybutyl methacrylate are copolymerized in a molar ratio of 2:3. The synthesis method is as follows: 200g of butyl acetate and 1.85g of azobisisobutyronitrile are added to a reaction flask and stirred at room temperature to dissolve. Then 45.36g of imidazole tetrafluoroethyl methacrylate and 42.7g of hydroxybutyl methacrylate are added, stirred and heated to 110°C and reacted for 3h, and then 2.7g of dodecanethiol is added to continue the reaction for 30min, cooled to room temperature, and the polymer is precipitated with 110g of methanol and vacuum dried at 90°C for 3h to obtain additive B powder, with a weight average molecular weight (determined by gel permeation chromatography) Mw=8300 and a molecular weight distribution of 1.33.

[0053]

[0054] Preparation Example 3

[0055] Imidazole hexafluoropropyl methacrylate and hydroxybutyl methacrylate are copolymerized in a molar ratio of 2:3. The synthesis method is as follows: 200g of butyl acetate and 1.85g of azobisisobutyronitrile are added to a reaction flask and stirred at room temperature to dissolve. Then 54.36g of imidazole hexafluoropropyl methacrylate and 42.7g of hydroxybutyl methacrylate are added, stirred and heated to 110°C and reacted for 3h, and then 2.7g of dodecanethiol is added to continue the reaction for 30min, cooled to room temperature, and the polymer is precipitated with 110g of methanol and vacuum dried at 90°C for 3h to obtain additive C powder, with a weight average molecular weight (determined by gel permeation chromatography) Mw=8700 and a molecular weight distribution of 1.38.

[0056]

[0057] Preparation Example 4

[0058] Hexafluoroisopropyl methacrylate and hydroxybutyl methacrylate are copolymerized in a molar ratio of 2:3. The synthesis method is as follows: 200g of butyl acetate and 1.85g of azobisisobutyronitrile are added to a reaction flask and stirred at room temperature to dissolve. Then 42.48g of hexafluoroisopropyl methacrylate and 42.7g of hydroxybutyl methacrylate are added, stirred and heated to 110°C and reacted for 3h, and then 2.7g of dodecanethiol is added to continue the reaction for 30min, cooled to room temperature, and the polymer is precipitated with 110g of methanol and vacuum dried at 90°C for 3h to obtain additive D powder. The weight average molecular weight (measured by gel permeation chromatography) of the polymer is Mw=8100, and the molecular weight distribution is 1.30.

[0059]

[0060] Example 1

[0061] The additive A obtained in the above-mentioned Preparation Example 1 is combined with propylene glycol monomethyl ether acetate (PMA, as a solvent), phenolic resin (linear phenolic resin, Shengquan 8850), photosensitizer (Toyo PAC320), crosslinking agent (Sanhe MW390), and other additives to form a photoresist composition. The specific composition and content are shown in Table 1.

[0062] Example 2

[0063] The difference between Example 2 and Example 1 is that Example 2 uses the additive B prepared in Preparation Example 2 to prepare the photoresist composition.

[0064] Example 3

[0065] The difference between Example 3 and Example 1 is that Example 3 uses the additive C prepared in Preparation Example 3 to prepare the photoresist composition.

[0066] Example 4

[0067] The difference between Example 4 and Example 1 is that Example 4 uses the additive D prepared in Preparation Example 4 to prepare a photoresist composition.

[0068] Example 5

[0069] The additive C obtained in the above Preparation Example 3 was combined with propylene glycol methyl ether (PM, as a solvent), ethyl lactate (EL, as a solvent), polyamic acid resin (self-made), photosensitizer (JF PAC435), crosslinking agent (Sanhe MW270), and other additives to form a photoresist composition. The specific composition and content are shown in Table 1.

[0070] Comparative Example 1

[0071] Comparative Example 1 is similar to Example 3, except that the fluorine-containing leveling agent F554 (DIC) without imidazole group is used in Comparative Example 1 to replace the additive C in Preparation Example 3. In addition, the specific structural formula of F554 is not disclosed by DIC Corporation.

[0072] The F554 leveling agent, propylene glycol monomethyl ether acetate (PMA, as a solvent), phenolic resin (linear phenolic resin, Shengquan 8830), photosensitizer (Toyo PAC430), crosslinking agent (Sanwa MW390), and other additives are combined to form a photoresist composition. The specific composition and content are shown in Table 1.

[0073] Effect test

[0074] The photoresist compositions prepared in Examples 1-5 and Comparative Example 1 were subjected to photolithography experiments under the same conditions, specifically comprising the following steps:

[0075] First, prepare a glass substrate, magnetron sputter a 200nm metal molybdenum layer on the glass substrate, irradiate with a UV cleaner for 1 minute and clean the surface of the glass substrate with deionized water. Then, evenly apply the photoresist composition on the surface of the glass substrate by spin coating, and test the uniformity of the film thickness. Pre-bake at 110°C for 140s to obtain a 1.5μm thick film layer, expose with 365nm ultraviolet light, with a distance of 0μm between the mask and the coating, and use 2.38% TMAH (tetramethylammonium hydroxide) developer. After developing at 23°C for 40s, rinse with water and dry. After development, bake at 130°C / 120s and use SF 6 , Cl 2 , O 2 Plasma etching is performed to test the etching film reduction rate.

[0076] The film thickness uniformity is tested by the 9-point method on the film surface, and the calculation formula is: Film thickness uniformity = (FT max -FT min ) / FT 平均 / 2, the smaller the value, the better the film thickness uniformity, where FT refers to film thickness, which is measured by ellipsometer. Film thickness uniformity is an indicator for evaluating the performance of photoresist coating; etching film reduction rate = 1-film thickness after etching / film thickness before etching, etching film reduction rate is an indicator for evaluating etching resistance, and the smaller the value, the better the etching resistance.

[0077] Table 1

[0078]

[0079]

[0080] As shown in Table 1, Examples 1-5 of the present invention exhibit excellent coating performance and etching resistance compared with Comparative Example 1. Specifically, the heteroaryl-containing additive of the present invention is conducive to improving the film thickness uniformity and etching resistance of the photoresist, and there is no obvious shrinkage cratering and edge shrinkage phenomenon.

[0081] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A photoresist additive, which is a polymer containing structural fragments of the following formula (1) and formula (2) in the main chain or the side chain, R 1 , R 2 , R 3 , R 4 are each independently H, F, Si, a C1-C10 aliphatic hydrocarbon group or a fluorinated aliphatic hydrocarbon group, a C6-C30 aryl group or a fluorinated C6-C30 aryl group, a C3-C30 heteroaryl group or a fluorinated C3-C30 heteroaryl group, wherein the heteroatom in the heteroaryl group or the fluorinated C3-C30 heteroaryl group is a nitrogen atom, provided that: R 1 -R 4 At least one of them is a group containing a fluorine atom, or R 1 -R 4 At least one of them is a C3-C30 nitrogen-containing heteroaryl group; The molecular weight Mw of the polymer is 3000-23000, the sum of m in all structural fragments of formula (1) is 5-20, and the sum of n in all structural fragments of formula (2) is 7-30.

2. A photoresist additive according to claim 1, characterized in that: The polymer is a polymer composed of structural fragments of formula (1) and formula (2), with a molecular weight of 4000-13000, the sum of m in all structural fragments of formula (1) is 8-20, the sum of n in all structural fragments of formula (2) is 10-30, and the molecular weight distribution is 1.2-1.

8. R 1 -R 4 At least one of them is a group containing a fluorine atom, and R 1 -R 4 At least one of them is a C3-C30 nitrogen-containing heteroaryl group.

3. A photoresist additive according to claim 1, characterized in that: R 1 -R 4 The groups except the group containing one fluorine atom or the C3-C30 nitrogen-containing heteroaryl group are each independently selected from the following groups: Hydrogen, methyl, ethyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl, 2-hydroxyethyl, decyl, sulfonic acid methyl, phenyl, isobornyl, trifluoromethyl, hexafluoropropyl, imidazolyl, pyridyl, quinolyl, naphthyl, anthracenyl, benzanthryl, phenanthryl, triphenylenyl, pyrenyl, fluoranthenyl, biphenyl, phenylene, terphenyl, triphenylene, fluorenyl.

4. A photoresist additive according to claim 1, characterized in that: R 1 -R 4 Each is independently selected from the following groups: * indicates the linking site to the polymer.

5. A photoresist additive according to claim 1, characterized in that: R 1 -R 4 At least one of the groups is a group having an imidazole structure.

6. Use of the photoresist additive according to any one of claims 1 to 5 as a leveling agent.

7. A photoresist composition, comprising an alkali-soluble resin, a photosensitizer, a cross-linking agent, the photoresist additive according to any one of claims 1 to 5, and a solvent.

8. The photoresist composition according to claim 7, wherein The photosensitizer is selected from diazonaphthoquinonesulfonyl chloride and a disubstituted ester compound of trihydroxybenzophenone, diazonaphthoquinonesulfonyl chloride and a trisubstituted ester compound of tetrahydroxybenzophenone, or diazonaphthoquinonesulfonyl chloride and a disubstituted ester compound of α,α,α'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene.

9. The photoresist composition according to claim 7, wherein The alkali-soluble resin is a linear phenolic resin or a polyamic acid resin. Preferably, the phenolic resin is a phenolic resin polymerized from cresol and formaldehyde, a phenolic resin polymerized from xylenol and formaldehyde, a phenolic resin polymerized from di-tert-butylphenol and formaldehyde, a phenolic resin polymerized from dihydroxynaphthalene and formaldehyde, a phenolic resin polymerized from phloroglucinol and formaldehyde, and a phenolic resin polymerized from xylenol, formaldehyde and salicylaldehyde. Preferably, the polyamic acid resin is polymerized from a dianhydride selected from trans-1,4-cyclohexanediamine, p-phenylenediamine, m-phenylenediamine, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 3,4'-diaminodiphenyl ether, 2,2'-bis(trifluoromethyl)benzidine, 3,3'-bis(trifluoromethyl)benzidine diamine, and a dianhydride selected from pyromellitic acid dianhydride, 1,6-difluoropyromellitic acid dianhydride, 1,6-bis(trifluoromethyl)pyromellitic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, and bis(3,4-dicarboxyphenyl)ether dianhydride.

10. The photoresist composition according to claim 7, wherein The crosslinking agent is an amino crosslinking agent, an epoxy crosslinking agent, an ether crosslinking agent or a urea crosslinking agent. The crosslinking agent is preferably hexamethylenetetramine, 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 1,4-butanediol diglycidyl ether, hexamethoxymethylmelamine, or trialkoxycarbonylaminotriazine 1,3-bis(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone.

11. The photoresist composition according to claim 7, wherein The solvent is selected from one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol butyl methyl ether, diethylene glycol butyl ethyl ether, diethylene glycol diethyl ether ethyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol butyl methyl ether, dipropylene glycol ethyl hexyl ether, triethylene glycol dimethyl ether, triethylene glycol tert-butyl ether, chloroform, xylene, ethyl lactate, γ-butyrolactone, N-methylpyrrolidone, benzyl alcohol, and dimethyl sulfoxide.

12. The photoresist composition according to claim 7, wherein Taking the total weight of the photoresist composition as 100%, the weight content of each component in the photoresist composition is: The balance is solvent and other additives.

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