Photoresist composition and application thereof

Abstract

The invention provides a photoresist composition and application thereof, the photoresist composition comprises a combination of phenolic hydroxyl group-containing polyimide precursor resin, a curing agent and a photosensitive compound, and the curing agent has a structure as shown in a formula I. Through the design of the curing agent with the structure as shown in the formula I and the compounding of the curing agent with the specific polyimide precursor resin, the photosensitive compound and other components, the curing temperature of the photoresist composition is effectively reduced, so that the photoresist composition can be subjected to sufficient curing cross-linking reaction at low temperature; the generated photoresist cured film has more excellent thermal stability and chemical corrosion resistance, and can be used in packaging processes of flexible semiconductors, panel displays and other devices.

Description

Technical Field

[0001] The present invention belongs to the technical field of photoresist materials, and particularly relates to a photoresist composition and its application. Background Art

[0002] Photoresist is one of the key electronic chemicals involved in the processing of large-scale integrated circuits. According to the exposure characteristics, photoresist can be divided into positive photoresist and negative photoresist. As a kind of commercialized photoresist, photosensitive polyimide is widely used in the packaging field of electronic devices such as semiconductors due to its high performance and simple process. Specifically, for example, in IC devices, RDL (redistribution layer), Bump layer, anti-radiation protection of devices, insulation layer, and in OLED devices, pixel definition layer (PDL), planarization layer (PLN), etc. Usually, photosensitive polyimide uses polyamic acid (ester) as a precursor, and then is cured by heating (300 °C or higher) to obtain polyimide. However, the problem with this preparation process is that the high-temperature heating and curing process not only consumes a large amount of energy, but also many electronic devices and semiconductor chips cannot withstand temperatures above 300 °C, and residual thermal stress remains in the devices, affecting the device performance. If the curing temperature is reduced, the imidization of polyamic acid (ester) is incomplete, which will lead to a decrease in the thermal stability and chemical resistance of the material, affecting the device stability. Therefore, the process of promoting curing at high temperature poses a great challenge to the yield of electronic devices and semiconductor devices, and effective curing cannot be achieved at low temperature; how to reduce the curing temperature of photosensitive polyimide and make the material obtained by low-temperature curing have excellent thermal stability and chemical resistance is an urgent problem to be solved in this field. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a photoresist composition and its application. By introducing a curing agent with a specific structure and compounding it with specific components such as a polyimide precursor resin, the curing temperature of the photoresist composition can be effectively reduced, and the photoresist cured film obtained by low-temperature curing has better thermal stability and chemical resistance.

[0004] To achieve this purpose, the present invention adopts the following technical solutions:

[0005] In the first aspect, the present invention provides a photoresist composition, which includes a combination of a polyimide precursor resin containing phenolic hydroxyl groups, a curing agent, and a photosensitive compound; the curing agent has the structure shown in Formula I:

[0006]

[0007] In Formula I, R1 and R2 each independently selected from substituted or unsubstituted methyl Any one of the following; - * represents the connection site of the group.

[0008] R 11 、R 12 、R 13 Each independently selected from substituted or unsubstituted C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) straight-chain or branched-chain alkyl, substituted or unsubstituted C3-C10 (such as C3, C4, C5, C6, C7, C8, C9, C10) cycloalkyl, substituted or unsubstituted C3-C10 (such as C3, C4, C5, C6, C7, C8, C9, C10) cycloalkenyl, substituted or unsubstituted C2-C20 (such as C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkenyl, C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkoxy, C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkylthio, C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) ester group, C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkylamino.

[0009] R1, R2, R 11 、R 12 、R 13The substituents described in [reference] are each independently selected from at least one of C1-C10 (such as C2, C3, C4, C5, C6, C7, C8, C9, etc.) alkoxy, C1-C10 (such as C2, C3, C4, C5, C6, C7, C8, C9, etc.) alkylthio, C1-C10 (such as C2, C3, C4, C5, C6, C7, C8, C9, etc.) ester group, C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkylamino, C3-C10 (such as C3, C4, C5, C6, C7, C8, C9, C10) cycloalkyl, and C3-C10 (such as C3, C4, C5, C6, C7, C8, C9, C10) cycloalkenyl.

[0010] In the present invention, the "substituted or unsubstituted" group may be substituted with one substituent or multiple substituents. When there are multiple substituents (at least 2), they may be the same or different substituents; when the same expression is involved hereinafter, it shall have the same meaning.

[0011] The photoresist composition provided by the present invention is a positive photoresist. The curing agent with the structure shown in Formula I is an amine oxide compound, which can decompose under heating conditions. On the one hand, it can catalyze the imidization of the polyimide precursor, and on the other hand, it can promote the crosslinking of the polyimide precursor resin, improving the thermal stability and chemical resistance of the material. Therefore, through the design of the curing agent and its compounding with a specific polyimide precursor resin and a photosensitive compound, the present invention effectively reduces the curing temperature of the photoresist composition, enabling it to undergo a sufficient curing crosslinking reaction at a low temperature. The resulting photoresist cured film has more excellent thermal stability, chemical resistance (chemical resistance), and excellent mechanical properties.

[0012] In the present invention, R1 and R2 in the curing agent are selected from substituted or unsubstituted methyl That is, for a group with a carbon atom number ≥ 2, there is no hydrogen on its β-carbon, otherwise the decomposition product has no effect on catalyzing imidization and crosslinking.

[0013] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved.

[0014] In the present invention, for the expression of chemical elements, unless otherwise specified, the concept of isotopes with the same chemical properties is included. For example, hydrogen (H) includes 1 H (protium), 2 H (deuterium, D), 3 H (tritium, T), etc.; carbon (C) includes12 C. 13 C, etc.

[0015] In the present invention, the expression "Ca-Cb" means that the number of carbon atoms in the group is ab; unless otherwise specified, the number of carbon atoms generally does not include the number of carbon atoms in the substituent.

[0016] In the present invention, “each independently” means that when there are multiple subjects, they may be the same as or different from each other.

[0017] In the present invention, the expression of a ring structure crossed by “—” indicates that the connection site is at any position on the ring structure that can form a bond.

[0018] In the present invention, "-*" and "*" both represent the connection site of a group.

[0019] In the present invention, the C1-C20 straight chain or branched alkyl group can be a straight chain or branched alkyl group of C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc., preferably a C1-C10 straight chain or branched alkyl group, illustratively including but not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-methylbutyl, n-pentyl, isopentyl, neopentyl, n-hexyl, neohexyl, 2-ethylhexyl, n-octyl, n-heptyl, n-nonyl, n-decyl, etc.

[0020] In the present invention, the C3-C10 cycloalkyl group may be a cycloalkyl group of C3, C4, C5, C6, C7, C8, C9, or C10, including a monocyclic alkyl group or a polycyclic alkyl group. A monocyclic alkyl group refers to an alkyl group containing a single cyclic structure, and a polycyclic alkyl group refers to a structure composed of two or more cycloalkyl groups sharing one or more carbon atoms on the ring; examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl groups.

[0021] In the present invention, the C3-C10 cycloalkenyl group may be a C3, C4, C5, C6, C7, C8, C9, or C10 cycloalkenyl group, and a specific example is a monovalent group formed by replacing a single bond in at least one ring of the aforementioned cycloalkyl group with C=C.

[0022] In the present invention, the C2-C20 alkenyl group may be a straight chain or branched alkenyl group of C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc., containing at least one C=C, illustratively including but not limited to: vinyl, propenyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, butadienyl, pentadienyl and the like.

[0023] The C1-C20 alkoxy group may be a straight-chain or branched-chain alkoxy group such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, or C18, preferably a C1-C10 alkoxy group. Specific examples thereof may be monovalent groups formed by connecting the aforementioned straight-chain or branched-chain alkyl groups to an O atom.

[0024] The C1-C20 alkylthio group may be a straight-chain or branched-chain alkylthio group such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, or C18, preferably a C1-C10 alkylthio group. Specific examples thereof may be monovalent groups formed by connecting the aforementioned straight-chain or branched-chain alkyl groups to an S atom.

[0025] The C1-C20 ester group may be an ester group such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, or C18, and the molecular structure contains or a monovalent group.

[0026] The C1-C20 alkylamino group may be an alkylamino group such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, or C18, and is a monovalent group formed by substituting at least 1 H in NH2 with the aforementioned straight-chain or branched-chain alkyl group.

[0027] The C1-C10 alkoxy group may be a straight-chain or branched-chain alkoxy group such as C2, C3, C4, C5, C6, C7, C8, C9, and specific examples thereof may be monovalent groups formed by connecting the aforementioned straight-chain or branched-chain alkyl groups to an O atom.

[0028] The C1-C10 alkylthio group may be a straight-chain or branched-chain alkylthio group such as C2, C3, C4, C5, C6, C7, C8, C9, and specific examples thereof may be monovalent groups formed by connecting the aforementioned straight-chain or branched-chain alkyl groups to an S atom.

[0029] The C1-C10 ester group may be an ester group such as C2, C3, C4, C5, C6, C7, C8, C9, and is a monovalent group containing or in the molecular structure.

[0030] Preferably, R1 and R2 are each independently selected from substituted or unsubstituted methyl groups.

[0031] Preferably, the substituents of R1 and R2 are each independently selected from at least one of C1-C6 (such as C1, C2, C3, C4, C5, C6) alkoxy groups, C1-C6 (such as C1, C2, C3, C4, C5, C6) alkylthio groups, C1-C6 (such as C1, C2, C3, C4, C5, C6) ester groups, C3-C6 (such as C3, C4, C5, C6) cycloalkyl groups, and C3-C6 (such as C3, C4, C5, C6) cycloalkenyl groups.

[0032] Preferably, the substituents of R1 and R2 are each independently selected from C1-C3 alkoxy groups and at least one of the following.

[0035] Preferably, the curing agent is selected from any one or a combination of at least two of the following compounds:

[0036]

[0037] Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the curing agent is 0.01-40 parts, for example, it can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts, etc., more preferably 0.05-30 parts, and even more preferably 0.1-25 parts.

[0038] Preferably, the phenolic hydroxyl group-containing polyimide precursor resin includes any one or a combination of at least two of phenolic hydroxyl group-containing polyamic acid, phenolic hydroxyl group-containing polyamic acid ester, phenolic hydroxyl group-containing polyamic acid-polyimide copolymer, and phenolic hydroxyl group-containing polyamic acid ester-polyimide copolymer.

[0039] Preferably, the phenolic hydroxyl group-containing polyimide precursor resin contains a structural unit represented by Formula II:

[0040]

[0041] In Formula II, R3 is selected from any one of a substituted or unsubstituted C6-C40 (such as C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C35, C36, C38, etc.) tetravalent aromatic group, a substituted or unsubstituted C4-C20 (such as C5, C6, C9, C10, C12, C14, C16, C18, etc.) tetravalent alicyclic group, and a C2-C20 (such as C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, etc.) tetravalent aliphatic group.

[0042] In Formula II, R4 is selected from any one of a substituted or unsubstituted divalent aromatic group having 6 to 40 carbon atoms (such as C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C35, C36, C38, etc.), a substituted or unsubstituted divalent alicyclic group having 4 to 20 carbon atoms (such as C5, C6, C9, C10, C12, C14, C16, C18, etc.), and a substituted or unsubstituted divalent aliphatic group having 2 to 20 carbon atoms (such as C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, etc.).

[0043] The substituents of the substituted groups in R3 and R4 are each independently selected from at least one of halogen, hydroxyl, a straight-chain or branched-chain alkyl group having 1 to 20 carbon atoms (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) which is unsubstituted or substituted with halogen, and an alkoxy group having 1 to 20 carbon atoms (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) which is unsubstituted or substituted with halogen.

[0044] In Formula II, at least one phenolic hydroxyl group is included in R3 and R4.

[0045] In Formula II, R5 is selected from any one of hydrogen and a straight-chain or branched-chain alkyl group having 1 to 20 carbon atoms (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) which is substituted or unsubstituted; the substituents of the substituted group in R5 are selected from at least one of alkoxy groups having 1 to 10 carbon atoms (such as C2, C3, C4, C5, C6, C7, C8, C9, etc.).

[0046] In Formula II, m ≥ 5, for example, it can be 5, 10, 50, 100, 500, 1000, 3000, 5000, 8000, 10000, 30000, 50000, 80000 or 100000, etc., and preferably 5 - 100000.

[0047] In the polyimide precursor resin of the present invention, the C6-C40 (e.g., C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26, C28, C30, C32, C35, C36, C38, etc.) tetravalent aromatic groups include C6-C40 aryl groups (e.g., phenyl, naphthyl, biphenyl, terphenyl, fluorenyl, anthracenyl, phenanthrenyl, triphenylene, naphthylene, etc.), and also include aryl groups connected by bridging bonds (single bonds, O, S, sulfoxide groups, sulfone groups, substituted or unsubstituted alkylene groups, etc.). The following "C6-C40 divalent aromatic groups" have similar examples.

[0048] The C4-C20 (e.g., C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, etc.) tetravalent alicyclic group, "alicyclic group" means a non-aromatic saturated or unsaturated cyclic structure, including a monocyclic, bridged, spiro or condensed ring, etc., illustratively including but not limited to: cyclobutane, cyclopentane, cyclohexane, bicyclooctane, etc. The following "C4-C20 divalent alicyclic group" has similar examples.

[0049] In the present invention, the halogen includes fluorine, chlorine, bromine or iodine; the "halogen substitution" means that at least one hydrogen in the group is replaced by a halogen (fluorine, chlorine, bromine or iodine), preferably fluorine substitution.

[0050] Preferably, the R3 is selected from any one of the following groups:

[0051] -* represents the attachment site of the group.

[0052] R 21 , R 22 , R 23 , R 24 , R 25 , R 26 Each is independently selected from hydrogen, halogen, hydroxyl, unsubstituted or halogen-substituted C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) straight or branched alkyl, unsubstituted or halogen-substituted C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkoxy, and is more preferably hydrogen, hydroxyl, fluorine, methyl, methoxy, perfluoromethyl or perfluoromethoxy.

[0053] L 21 Selected from single bond, -O-, -S-, carbonyl ( ), sulfonyl group ( ), sulfinyl group ( ), unsubstituted or R'-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) straight-chain or branched-chain alkylene group, unsubstituted or R'-substituted C6-C20 (such as C6, C9, C10, C12, C14, C16 or C18, etc.) arylene group, *-L 22 -Ar 21 -L 23 -*, any one of them.

[0054] L 22 、L 23 Each independently selected from a single bond, -O-, -S-, carbonyl group, sulfonyl group, sulfinyl group, unsubstituted or R'-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) straight-chain or branched-chain alkylene group, any one of them.

[0055] Ar 21 Selected from any one of unsubstituted or R'-substituted C6-C20 (such as C6, C9, C10, C12, C14, C16 or C18, etc.) arylene groups.

[0056] R' is selected from at least one of halogen, hydroxyl group, unsubstituted or halogen-substituted C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) straight-chain or branched-chain alkyl group, unsubstituted or halogen-substituted C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, etc.) alkoxy group.

[0057] Preferably, the L 21 is selected from a single bond, -O-, -S-, -CH2-, or any one of them.

[0058] Preferably, the R3 is selected from any one of the following groups:

[0059]

[0060] Among them, -* represents the connection site of the group.

[0061] Preferably, the R4 is selected from any one of the following groups:

[0062] - * represents the connection site of the group.

[0063] R 31 and R 32 each independently selected from halogen, hydroxy, unsubstituted or halogen-substituted C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C15 or C18, etc.) linear or branched alkyl, unsubstituted or halogen-substituted C1-C20 (such as C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C15 or C18, etc.) alkoxy, more preferably hydroxy, fluorine, methyl, methoxy, perfluoromethyl or perfluoromethoxy.

[0064] L 31 selected from single bond, -O-, -S-, carbonyl, sulfone, sulfoxide, unsubstituted or halogen-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) linear or branched alkylene, unsubstituted or halogen-substituted C6-C20 (such as C6, C9, C10, C12, C14, C16 or C18, etc.) arylene, *-L 32 -Ar 31 -L 33 -* of any one.

[0065] L 32 and L 33 each independently selected from single bond, -O-, -S-, carbonyl, sulfone, sulfoxide, unsubstituted or halogen-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) linear or branched alkylene of any one.

[0066] Ar 31 selected from any one of unsubstituted or R″-substituted C6-C20 arylene;

[0067] R″ is selected from halogen, hydroxy, unsubstituted or halogen-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) linear or branched alkyl, unsubstituted or halogen-substituted C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) alkoxy of any one.

[0068] u1 and u2 each independently selected from integers from 0 to 4, for example, can be 0, 1, 2, 3 or 4.

[0069] Preferably, the L 31 selected from single bond, -O-, -S-, -CH2-, or Any one of .

[0070] Preferably, the R4 is selected from any one of the following groups:

[0071]

[0072] Wherein, -* represents the attachment site of the group.

[0073] Preferably, R5 is selected from any one of hydrogen, substituted or unsubstituted C1-C6 (e.g. C1, C2, C3, C4, C5, C6) straight chain or branched alkyl; the substituted substituent in R5 is selected from at least one of C1-C6 (e.g. C1, C2, C3, C4, C5, C6) alkoxy.

[0074] Preferably, R5 is selected from any one of hydrogen, C1-C3 straight chain or branched chain alkyl (methyl, ethyl, n-propyl, isopropyl), and methoxy-substituted C1-C3 straight chain or branched chain alkyl.

[0075] Preferably, the weight average molecular weight of the polyimide precursor resin containing phenolic hydroxyl groups is 1000-100000, for example, it can be 1000, 2000, 3000, 5000, 8000, 10000, 15000, 20000, 25000, 30000, 35000, 40000, 45000, 50000, 55000, 60000, 70000, 80000 or 90000, etc., more preferably 5000-50000.

[0076] Preferably, the polyimide precursor resin containing phenolic hydroxyl groups can be prepared by a method known in the art, exemplarily including any one of the following routes:

[0077] (1) directly polymerizing diamine with dianhydride to obtain polyamic acid, and then esterifying to obtain polyamic acid ester;

[0078] (2) reacting a dianhydride with an alcohol to form a dicarboxylic acid diester, which is then reacted with thionyl chloride to form a diacyl chloride diester, which is then polymerized with a diamine compound to obtain a polyamic acid ester;

[0079] (3) A dianhydride is reacted with an alcohol to form a dicarboxylic acid diester, which is then reacted with a diamine compound in the presence of a dehydrating agent such as cyclohexylcarbodiimide to obtain a polyamic acid ester.

[0080] Preferably, the preparation method of the polyimide precursor resin containing phenolic hydroxyl groups comprises: firstly reacting a diamine monomer (NH2-R4-NH2) with a dianhydride monomer ( )Polymerization is carried out to obtain polyamic acid; the polyamic acid is subjected to an esterification reaction to obtain the polyimide precursor resin.

[0081] Preferably, the reagents for the esterification reaction include N,N-dimethylformamide dimethyl acetal and / or N,N-dimethylformamide diethyl acetal.

[0082] Preferably, the photosensitive compound is a compound containing a diazonaphthoquinone group.

[0083] Preferably, the structure of the diazonaphthoquinone group is or -* represents the connection site of the group.

[0084] Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the photosensitive compound is 0.1 - 40 parts, for example, it can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts, etc.

[0085] Preferably, the photoresist composition further includes a crosslinking agent and / or an auxiliary agent.

[0086] Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the crosslinking agent is 0.1 - 40 parts, for example, it can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts, etc.

[0087] Preferably, the crosslinking agent contains any one or a combination of at least two of phenolic hydroxyl group, benzyl alcohol group, and benzyl ether group.

[0088] Preferably, the auxiliary agent includes any one or a combination of at least two of silane coupling agent, surfactant, and curing accelerator.

[0089] Preferably, in addition to alkoxy groups, the silane coupling agent may further include at least one of amino group, epoxy group, isocyanate group, alkenyl group, acryloyloxy group, methacryloyloxy group, ureido group, and mercapto group.

[0090] Preferably, the surfactant includes any one or a combination of at least two of fluorine-containing surfactant, polyethylene glycol-containing surfactant, and silicone-oxygen structure-containing surfactant, which can function as a leveling agent and can play a role in improving the flatness of the film and improving the problem of too high film thickness at the edge of the substrate.

[0091] Preferably, the curing accelerator includes any one or a combination of at least two of photoacid generators, thermal acid generators, photobase generators, and thermal base generators.

[0092] Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the auxiliary agent is 0.001 - 10 parts, for example, it can be 0.002 parts, 0.005 parts, 0.008 parts, 0.01 parts, 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts or 9 parts, etc.

[0093] Preferably, the photoresist composition includes the following components by mass parts:

[0094]

[0095] Preferably, the photoresist composition further includes a solvent.

[0096] Preferably, the solvent is a common solvent in the art, including but not limited to: any one or a combination of at least two of γ-butyrolactone, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether formate, propylene glycol monoethyl ether formate, ethyl lactate, butyl lactate, N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0097] Preferably, the amount of the solvent is such that the solid content of the photoresist composition is 5 - 45 wt%, for example, it can be 8 wt%, 10 wt%, 12 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 25 wt%, 28 wt%, 30 wt%, 32 wt%, 35 wt%, 38 wt%, 40 wt%, 42 wt% or 44 wt%, etc.

[0098] In a second aspect, the present invention provides a photoresist cured film, which is prepared from the photoresist composition as described in the first aspect.

[0099] In a third aspect, the present invention provides an application of the photoresist composition as described in the first aspect and the photoresist cured film as described in the second aspect in semiconductor devices or flat panel display devices.

[0100] Preferably, the photosensitive resin composition is used for stress buffer materials, passivation layers in semiconductor devices, pixel defining layers, planarization layers, etc. in display devices.

[0101] Preferably, after the photoresist composition is coated, pre-baked, lithographed, developed, and cured, a photoresist cured film can be formed and permanently retained in semiconductor devices or flat panel display devices (display panels). The photoresist cured film has excellent heat resistance and chemical resistance and can be used in the encapsulation processes of flexible semiconductor, flat panel display, and other devices.

[0102] Preferably, the curing temperature ≤ 250 °C, for example, it can be 250 °C, 240 °C, 230 °C, 220 °C, 210 °C, 200 °C, etc.

[0103] Compared with the prior art, the present invention has the following beneficial effects:

[0104] In the photoresist composition provided by the present invention, through the design of the curing agent with the structure shown in Formula I and its compounding with specific polyimide precursor resins, photosensitive compounds, and other components, the curing temperature of the photoresist composition is effectively reduced, making its curing temperature ≤ 250 °C. It can undergo a sufficient curing crosslinking reaction at low temperature, and the resulting photoresist cured film has more excellent thermal stability and chemical corrosion resistance, lower outgassing volume, and excellent mechanical properties, and can be used in the encapsulation processes of flexible semiconductor, flat panel display, and other devices. Specific Embodiments

[0105] The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0106] In the following specific embodiments of the present invention, the weight average molecular weight of the polyimide precursor resin is measured by gel permeation chromatography (GPC). The test instrument is a Viscotek gel permeation chromatograph from Malvern Instruments, with a D6000M chromatographic column.

[0107] Preparation Example 1: Preparation of Polyimide Precursor Resin PI-1

[0108] The polyimide precursor resin PI-1 was prepared as follows: Under nitrogen protection, 4.51 g of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane was dissolved in 20 mL of N-methylpyrrolidone (NMP), and the temperature was lowered to 0 °C. A mixture of 3.87 g of 3,3,4,4-diphenylether tetracarboxylic dianhydride and 12 g of NMP was quickly added to the reaction system, and the reaction was maintained at 0 °C for 5 h. The temperature was raised to 60 °C, and 2.68 g of N,N-dimethylformamide dimethyl acetal was slowly added dropwise to the reaction system, and the reaction was maintained at 60 °C for 2 h. The temperature was lowered to room temperature, and the reaction solution was poured into 300 mL of deionized water. The precipitate was collected by filtration, and the precipitate was vacuum dried at 50 °C for 24 h to obtain the polyimide precursor resin PI-1, with a weight average molecular weight of 8500.

[0109] Preparation Example 2

[0110] The polyimide precursor resin PI-2 was prepared as follows: Under nitrogen protection, 3.48 g of 2,2-bis(4-hydroxy-3-aminophenyl)propane was dissolved in 20 mL of NMP, and the temperature was lowered to 0 °C. A mixture of 3.87 g of 3,3,4,4-diphenylether tetracarboxylic dianhydride and 12 g of NMP was quickly added to the reaction system, and the reaction was carried out at 0 °C for 5 h. The temperature was raised to 60 °C, and 2.68 g of N,N-dimethylformamide dimethyl acetal was slowly added dropwise to the reaction system, and the reaction was carried out at 60 °C for 2 h. The temperature was lowered to room temperature, and the reaction solution was poured into 300 mL of deionized water. The precipitate was collected by filtration, and the precipitate was vacuum dried at 50 °C for 24 h to obtain the polyimide precursor resin PI-2 with a weight average molecular weight of 9500.

[0111] Comparative Preparation Example 1: Preparation of polyimide precursor resin PI-D1

[0112] The polyimide precursor resin PI-D1 was prepared as follows: Under nitrogen protection, 4.11 g of 2,2-bis(3-aminophenyl)hexafluoropropane was dissolved in 20 mL of NMP, and the temperature was lowered to 0 °C. A mixture of 3.87 g of 3,3,4,4-diphenylether tetracarboxylic dianhydride and 12 g of NMP was quickly added to the reaction system, and the reaction was carried out at 0 °C for 5 h. The temperature was raised to 60 °C, and 2.68 g of N,N-dimethylformamide dimethyl acetal was slowly added dropwise to the reaction system, and the reaction was carried out at 60 °C for 2 h. The temperature was lowered to room temperature, and the reaction solution was poured into 300 mL of deionized water. The precipitate was collected by filtration, and the precipitate was vacuum dried at 50 °C for 24 h to obtain the polyimide precursor resin PI-D1 with a weight average molecular weight of 8300.

[0113] Example 1

[0114] A positive photoresist composition comprises the following components by mass: 100 parts of polyimide precursor resin PI-1 (Preparation Example 1), 20 parts of a photosensitive compound, 10 parts of a crosslinking agent, 5 parts of a curing agent, 1 part of a fluorine-containing surfactant, 1 part of a silane coupling agent (Shin-Etsu Chemical KBM403), and 850 parts of γ-butyrolactone;

[0115] Among them, the photosensitive compound is Q is The crosslinking agent is The curing agent is A1( Trimethylamine oxide).

[0116] The preparation method of the photoresist composition is as follows: All components are mixed according to the formula amount and dissolved uniformly to obtain the photoresist composition.

[0117] A photoresist cured film is prepared using the photoresist composition provided in this embodiment. The specific method includes: coating the photoresist composition on a 4-inch square glass substrate by spin coating, pre-baking at 120 °C for 180 s to remove most of the solvent, and forming a film with a thickness of about 10 μm. Exposure without a mask is carried out under an ultraviolet exposure machine to decompose the photosensitive compound, and then the coated glass substrate is placed in a clean oven at 200 °C under nitrogen protection (oxygen concentration < 20 ppm) and cured for 60 min to obtain the photoresist cured film.

[0118] Examples 2-4, Comparative Examples 1-3

[0119] A positive photoresist composition and the obtained photoresist cured film are different from those in Example 1 only in that at least one of the type of polyimide precursor resin, the type of curing agent, the amount of curing agent, and the curing temperature of the photoresist cured film is different, as shown in Table 1 specifically; items not listed in Table 1 are the same as those in Example 1.

[0120] Table 1

[0121]

[0122] In Table 1, "--" represents that this component is not added; Curing Agent A1 is Curing Agent A2 is The curing agent D1 in Comparative Example 4 is

[0123] Perform performance tests on the aforementioned photoresist composition and photoresist cured film, and the specific content is as follows:

[0124] (1) Mechanical properties

[0125] Using the spin coating method, coat the photoresist composition on a 4-inch square glass substrate to form a film with a thickness of about 10 μm. After exposure and development under an ultraviolet exposure machine, a standard spline pattern with a width of 10 mm is formed. Place the coated glass substrate in a clean oven at 200 °C under nitrogen protection (oxygen concentration < 20 ppm) and cure for 60 min. Immerse the cured sample in a 5% HF aqueous solution for more than 5 min to make it peel off naturally, quickly rinse it with deionized water, and then heat it at 200 °C (under nitrogen protection) for 30 min to obtain a test standard spline with a film thickness of 10 μm. Test the mechanical properties with a universal material testing machine, displacement rate 5 mm / min, environment 23 °C, humidity 50 ± 5%.

[0126] (2) Outgass test (outgassing amount test):

[0127] Sample preparation: The prepared photoresist composition was coated on a 4-inch square glass substrate by spin coating (250 rpm), pre-baked at 120 °C for 180 s to remove most of the solvent, and then the coated glass substrate was cured in a clean oven at 180 °C under nitrogen protection (oxygen concentration < 20 ppm) for 1 h. The film was scraped off and stored in a vacuum-sealed manner for later use.

[0128] Measurement of gas evolution: Using the purge and trap method, the collected cured film was heated at 230 °C for 30 min under a helium stream, and the evolved components were adsorbed by an adsorbent. At 250 °C, the adsorbed components were desorbed for 5 min and analyzed by gas chromatography-mass spectrometry (GC-MS); meanwhile, n-hexadecane was selected as a reference substance to draw a working standard curve, and the gas evolution amount converted according to n-hexadecane as the standard was calculated.

[0129] (3) Chemical resistance performance test

[0130] The prepared photoresist composition was coated on a 4-inch square glass substrate by spin coating (250 rpm), pre-baked at 120 °C for 180 s to remove most of the solvent, and the film thickness t was measured. Then the coated glass substrate was cured in a clean oven at 200 °C under nitrogen protection (oxygen concentration < 20 ppm) for 1 h, and the film thickness t1 was measured by ellipsometry. The coated glass substrate was immersed in a stripping solution (TOK106) at 50 °C for etching for 130 s. At room temperature, it was immersed in N-methylpyrrolidone (NMP), γ-butyrolactone (GBL), propylene glycol monomethyl ether (PM), and ethyl lactate (EL) for 15 min, taken out and quickly rinsed with deionized water, and then cured in a clean oven at 200 °C under nitrogen protection (oxygen concentration < 20 ppm) for 30 min. The film thickness t2 was measured by ellipsometry, and the film thickness changes before and after etching were calculated, and the corresponding film thickness change rate Δt was calculated according to the following formula:

[0131]

[0132] The test results are shown in Table 2 and Table 3:

[0133] Table 2

[0134] Curing Temperature (°C) Tensile Strength (MPa) Elongation at Break (%) Outgass (ppm) Example 1 200 80 10 800 Example 2 200 115 15 350 Example 3 200 98 13 570 Example 4 200 109 11 790 Comparative Example 1 200 55 9 1570 Comparative Example 2 200 60 10 1238 Comparative Example 3 250 78 11 954 Comparative Example 4 200 75 14 1030

[0135] Table 3

[0136]

[0137] In Table 3, "-" indicates no significant difference, that is, there is no obvious difference in the film thickness change before and after immersion in the corresponding solvent.

[0138] Combined with the foregoing test data, in the photoresist composition provided by the present invention, through the design of the curing agent with the structure shown in Formula I and its compounding with specific polyimide precursor resins, photosensitive compounds and other components, the curing temperature of the photoresist composition is effectively reduced, so that sufficient curing crosslinking reaction occurs at 200 °C. The resulting photoresist cured film has more excellent thermal stability and chemical corrosion resistance, and lower gas evolution. In Examples 1-2, curing agent A1 was added. Under the low-temperature (200 °C) curing condition, the tensile strength remained at a high level (>80 MPa). When soaked in stripping solution and NMP, the film reduction rate was small, and there was no obvious film reduction when soaked in solvents. At the same time, the gas evolution was also low. When the content of the curing agent increases, the mechanical properties and chemical resistance of the cured film will improve. When different precursor resins (Example 3) and different curing agents (Example 4) are used, the photoresists after low-temperature curing can maintain excellent mechanical properties, thermal stability and chemical resistance. When no curing agent is used (Comparative Example 1), due to the low curing temperature, the resin is not completely cured, the tensile strength of the photoresist is low, the gas evolution is large, and the chemical resistance is also poor. If the resin structure does not contain phenolic hydroxyl groups (Comparative Example 2), the resin cannot crosslink with the formaldehyde generated by the decomposition of the curing agent during the curing process, and the mechanical properties and chemical resistance of the photoresist will also decrease. In Comparative Example 3, no curing agent was added to the resin. Although the curing temperature was increased and the imidization degree of the resin was increased, no crosslinking reaction occurred and the thermal stability was also poor (the gas evolution was greater than 900 ppm). When a common curing agent is used (Comparative Example 4), this curing agent can only increase the imidization degree of the resin, but cannot promote the crosslinking reaction, and the thermal stability and chemical resistance of the photoresist are also poor.

[0139] The applicant declares that the present invention uses the above examples to illustrate the photoresist composition and its application of the present invention, but the present invention is not limited to the above examples, that is, it does not mean that the present invention must rely on the above examples to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A photoresist composition, characterized in that, The photoresist composition comprises a combination of a phenolic hydroxyl group-containing polyimide precursor resin, a curing agent, and a photosensitive compound; The curing agent has the structure shown in Formula I: Among them, R1 and R2 are each independently selected from substituted or unsubstituted methyl, any one of the following; -* represents the connection site of the group; R 11 、R 12 、R 13 Each independently selected from any one of substituted or unsubstituted C1-C20 linear or branched alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C3-C10 cycloalkenyl, substituted or unsubstituted C2-C20 alkenyl, C1-C20 alkoxy, C1-C20 alkylthio, C1-C20 ester group, C1-C20 alkylamino; R1, R2, R 11 , R 12 , R 13 The substituents described in are each independently selected from at least one of C1-C10 alkoxy, C1-C10 alkylthio, C1-C10 ester group, C1-C20 alkylamino, C3-C10 cycloalkyl, and C3-C10 cycloalkenyl.

2. The photoresist composition according to claim 1, wherein R1 and R2 are each independently selected from substituted or unsubstituted methyl; Preferably, the substituents in R1 and R2 are each independently selected from at least one of C1-C6 alkoxy, C1-C6 alkylthio, C1-C6 ester group, C3-C6 cycloalkyl, and C3-C6 cycloalkenyl, more preferably at least one of C1-C3 alkoxy, and the like.

3. The photoresist composition according to claim 1, wherein The curing agent is selected from any one or a combination of at least two of the following compounds:

4. The photoresist composition according to claim 1, characterized in that, Based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the curing agent is 0.01 - 40 parts, preferably 0.05 - 30 parts, and more preferably 0.1 - 25 parts.

5. The photoresist composition according to claim 1, characterized in that, The phenolic hydroxyl group-containing polyimide precursor resin contains a structural unit shown in Formula II: Wherein, R3 is selected from any one of a substituted or unsubstituted C6 - C40 tetravalent aromatic group, a substituted or unsubstituted C4 - C20 tetravalent alicyclic group, and a C2 - C20 tetravalent aliphatic group; R4 is selected from any one of a substituted or unsubstituted C6 - C40 divalent aromatic group, a substituted or unsubstituted C4 - C20 divalent alicyclic group, and a substituted or unsubstituted C2 - C20 divalent aliphatic group; The substituents in R3 and R4 are each independently selected from at least one of halogen, hydroxyl, unsubstituted or halogen-substituted C1 - C20 straight-chain or branched-chain alkyl, and unsubstituted or halogen-substituted C1 - C20 alkoxy; At least one phenolic hydroxyl group is included in R3 and R4; R5 is selected from any one of hydrogen, substituted or unsubstituted C1 - C20 straight-chain or branched-chain alkyl; the substituent in R5 is selected from at least one of C1 - C10 alkoxy; m≥5。 6. The photoresist composition according to claim 5, wherein R3 is selected from any one of the following groups: - *Represents the attachment site of the group; R 21 、R 22 、R 23 、R 24 、R 25 、R 26 each independently selected from any one of hydrogen, halogen, hydroxyl, unsubstituted or halogen-substituted C1-C20 straight-chain or branched-chain alkyl, and unsubstituted or halogen-substituted C1-C20 alkoxy; L 21 Selected from a single bond, -O-, -S-, a carbonyl group, a sulfone group, a sulfoxide group, an unsubstituted or R'-substituted C1-C10 straight-chain or branched alkylene group, an unsubstituted or R'-substituted C6-C20 arylene group, *-L 22 -Ar 21 -L 23 -*; L 22 and L 23 each independently selected from any one of a single bond, -O-, -S-, a carbonyl group, a sulfone group, a sulfoxide group, an unsubstituted or R'-substituted C1-C10 straight-chain or branched alkylene group; Ar 21 any one selected from unsubstituted or R'-substituted C6-C20 arylene groups; R' is selected from at least one of halogen, hydroxyl, unsubstituted or halogen-substituted C1 - C20 straight-chain or branched-chain alkyl, and unsubstituted or halogen-substituted C1 - C20 alkoxy; Preferably, R3 is selected from any one of the following groups: Among them, -* represents the connection site of the group.

7. The photoresist composition according to claim 5, wherein, R4 is selected from any one of the following groups: - *Represents the attachment site of the group; R 31 、R 32 each independently selected from any one of halogen, hydroxy, unsubstituted or halogen-substituted C1-C20 straight-chain or branched alkyl, and unsubstituted or halogen-substituted C1-C20 alkoxy; L 31 Selected from a single bond, -O-, -S-, a carbonyl group, a sulfone group, a sulfoxide group, an unsubstituted or halogen-substituted C1-C10 straight-chain or branched-chain alkylene group, an unsubstituted or halogen-substituted C6-C20 arylene group, *-L 32 -Ar 31 -L 33 -*, any one of them; L 32 and L 33 each independently selected from any one of a single bond, -O-, -S-, a carbonyl group, a sulfone group, a sulfoxide group, an unsubstituted or halogen-substituted C1-C10 straight-chain or branched-chain alkylene group; Ar 31 Any one selected from unsubstituted or R”-substituted C6-C20 arylene groups; R” is selected from any one of halogen, hydroxyl, unsubstituted or halogen-substituted C1 - C10 straight-chain or branched-chain alkyl, and unsubstituted or halogen-substituted C1 - C10 alkoxy; u1 and u2 are each independently selected from integers of 0 - 4; Preferably, R4 is selected from any one of the following groups: Among them, -* represents the connection site of the group.

8. The photoresist composition according to claim 1, characterized in that, The weight-average molecular weight of the phenolic hydroxyl group-containing polyimide precursor resin is 1000 - 100000, preferably 5000 - 50000.

9. The photoresist composition according to claim 1, wherein The photosensitive compound is a compound containing a diazonaphthoquinone group; Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the photosensitive compound is 0.1 - 40 parts.

10. The photoresist composition according to claim 1, wherein The photoresist composition further includes a crosslinking agent and / or an auxiliary agent; Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the crosslinking agent is 0.1 - 40 parts; Preferably, the auxiliary agent includes any one or a combination of at least two of a silane coupling agent, a surfactant, and a curing accelerator; Preferably, based on 100 parts by mass of the phenolic hydroxyl group-containing polyimide precursor resin, the mass of the auxiliary agent is 0.001 - 10 parts; Preferably, the photoresist composition further comprises a solvent; Preferably, the amount of the solvent is such that the solid content of the photoresist composition is 5-45 wt%.

11. A photoresist cured film, characterized in that, The photoresist cured film is prepared from the photoresist composition according to any one of claims 1-10.

12. Use of a photoresist composition according to any one of claims 1-10 and a photoresist cured film according to claim 11 in a semiconductor device or a flat panel display device.

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