Positive photoresist composition as well as preparation method and application thereof

Abstract

The invention provides a positive photoresist composition as well as a preparation method and application thereof, and the positive photoresist composition comprises the following components in parts by weight: 100 parts of modified phenolic resin, 0.5-10 parts of a diazonaphthoquinone compound and 0.01-0.1 part of a photoacid generator, the molecular structure of the modified phenolic resin comprises a structure as shown in a formula I. Phenolic resin with a specific structure is matched with a diazonaphthoquinone compound and a photoacid generator, so that the resolution and photosensitivity of the photoresist can be effectively improved on the premise of ensuring low film residue rate of the photoresist, a PEB process is not needed, the morphology of the photoresist is not influenced by trace alkali in air after development, and the service life of the photoresist is prolonged. And the industrial requirements of low cost and high performance are met.

Description

Technical Field

[0001] This invention belongs to the field of photoresist materials technology, specifically relating to a positive photoresist composition, its preparation method, and its application. Background Technology

[0002] Photoresist is a crucial upstream material in the manufacture of organic light-emitting diode (OLED) panels. It's a composition used for pattern transfer and is generally classified into positive and negative photoresists. The method for forming patterns using positive photoresist involves coating a layer of photoresist onto a substrate, exposing the photoresist to light through a mask. After exposure, the solubility of the photoresist in an alkaline solution changes; the solubility increases in the exposed areas, while it decreases in the unexposed areas. After development in an alkaline solution, the desired pattern is formed on the substrate. Commonly used exposure light sources include G-line (436nm) and I-line (365nm). G-line photoresist offers high sensitivity but lower resolution, while I-line photoresist offers high resolution but slower sensitivity.

[0003] Traditional OLED array positive photoresists consist of phenolic resin, diazonaphthoquinone compounds, additives, and solvents. For example, CN110597016A proposes using three photosensitive compounds to improve the resolution and sensitivity of the photoresist composition to meet actual production needs. However, this type of photoresist offers limited improvement in sensitivity and resolution, failing to meet the growing demands of OLED panel production. Furthermore, while improving sensitivity, this type of photoresist cannot effectively balance maintaining the residual film yield. Additionally, existing technologies disclose the use of tert-butoxyloxy or tert-butoxy groups to protect the phenolic hydroxyl groups in the phenolic resin, then combining them with a photoacid generator (PAG) / photoactive o-diazonaphthoquinone sulfonate (PAC) to improve the photoresist's sensitivity and resolution. However, this system requires a post-exposure baking (PEB) process during use due to the high activation energy of the protecting groups -tert-butoxyloxy or tert-butoxy groups to remove the protection. Moreover, the morphology of the photoresist after development is easily affected by trace amounts of alkali in the air. However, with the rapid development of the OLED display panel industry, the industry's demand for low cost and high capacity is increasing. The PEB process seriously affects the production cycle, making the improvement of the sensitivity of this system's photoresist meaningless and unable to meet the production line capacity requirements. In addition, the filtration of trace amounts of alkali in the production environment also greatly increases costs.

[0004] Therefore, there is an urgent need to develop a positive photoresist that is highly sensitive, has high resolution, is PEB-free, is insensitive to alkali in the air, and can guarantee the residual film yield. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a positive photoresist composition, its preparation method, and its applications. This positive photoresist composition solves the problem in existing technologies where positive photoresists cannot simultaneously achieve high sensitivity and high residual film yield, or where a PEB process is required.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a positive photoresist composition, comprising, by weight, 100 parts of modified phenolic resin, 0.5 to 10 parts of diazonaphthoquinone compound (PAC), and 0.01 to 0.1 parts of photoacid-generating agent (PAG). The modified phenolic resin has a molecular structure including the structure shown in Formula I.

[0008]

[0009] Wherein, R1 is selected from R 11 R 12 Each is independently selected from C1-C6 straight-chain or branched alkyl groups; R 11 R 12 They are either not connected or linked by chemical bonds to form a ring; "*" indicates the linking site; R2 is selected from C1 to C6 straight-chain or branched alkyl groups; n1 is selected from integers from 0 to 3, for example, 0, 1, 2, 3, etc.; n≥1, for example, 1, 2, 5, 10, 20, 50, 100, 200, 400, 600, etc.

[0010] In this invention, the modified phenolic resin has a molecular structure containing the structure shown in Formula I. This means that by protecting the phenolic hydroxyl groups in the phenolic resin with low activation energy through acetal or ketal formation to varying degrees, the alkali solubility of the film-forming resin can be reduced, resulting in less development loss in unexposed areas, and eliminating the need for a PEB process. PAC and PAG act together as photosensitizers. PAC interacts with the unprotected phenolic resin, inhibiting the dissolution of unexposed areas in the developer. In exposed areas, PAG generates protic acid, catalyzing a chain deprotection reaction in the protected phenolic resin at room temperature, thereby improving photosensitivity and resolution. Therefore, by using a phenolic resin with a specific structure in combination with PAC and PAG, the photoresist possesses the characteristics of both a phenolic resin / diazonaphthoquinone system and a chemically amplified photoresist system. This improves the resolution and photosensitivity of the photoresist while maintaining a low residual film rate, eliminating the need for a PEB process, and ensuring that its morphology after development is unaffected by trace amounts of alkali in the air, meeting the industry requirements of low cost and high performance.

[0011] In this invention, the modified phenolic resin is obtained by modifying phenolic resin (i.e., The phenolic hydroxyl groups in the resin are protected with low activation energy by acetal or ketal to varying degrees, thereby making the molecular chain of the phenolic resin contain the structure shown in Formula I, thus obtaining the modified phenolic resin.

[0012] In this invention, 0.5 to 10 parts of the diazonoquinone compound can be, for example, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts, etc.

[0013] In this invention, if the content of the diazonoquinone compound is too high, it will result in a slow photosensitivity speed, which cannot meet the high sensitivity requirements of the panel production line.

[0014] In this invention, 0.01 to 0.1 parts of photo-induced acid-producing agent can be, for example, 0.01 parts, 0.015 parts, 0.02 parts, 0.025 parts, 0.03 parts, 0.035 parts, 0.04 parts, 0.045 parts, 0.05 parts, 0.055 parts, 0.06 parts, 0.065 parts, 0.07 parts, 0.075 parts, 0.08 parts, 0.085 parts, 0.09 parts, 0.095 parts, 0.1 parts, etc.

[0015] In this invention, if the content of the photoacid-generating agent is too high, the stability of the photoresist deteriorates, the process window narrows, and the defect rate increases.

[0016] In this invention, C1-C6 straight-chain or branched alkyl groups refer to straight-chain or branched alkyl groups with 1 to 6 carbon atoms, such as C1, C2, C3, C4, C5, and C6; exemplary examples include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, and n-hexyl. The same expressions used below have the same meaning.

[0017] In this invention, the chemical bonds in the ring formed by chemical bonds include single bonds.

[0018] Preferably, R1 is selected from... Any one of them, more preferably R1 is selected from "*" indicates a connection point.

[0019] Preferably, R2 is selected from methyl.

[0020] Preferably, the molar percentage content of the structure shown in Formula I in the modified phenolic resin is 5% to 50%, for example, it can be 5%, 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, etc.; preferably 20% to 34%, and particularly preferably 21% to 29%.

[0021] In this invention, if the molar percentage content of the structure shown in Formula I is too low, the contrast will be insufficient; if it is too high, the photosensitivity will be slow and the sensitivity will be low.

[0022] Preferably, the weight-average molecular weight (Mw) of the modified phenolic resin is 2000 to 10000, for example, it can be 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 6500, 7000, 7500, 8000, 8500, 9000, 9500, 9800, etc.

[0023] Preferably, the diazonoquinone compound includes compounds having the structure shown in Formula II and / or compounds having the structure shown in Formula III.

[0024]

[0025] Among them, R1, R2, R3, R4, R5, R6, and R7 are each independently selected from H, Any one of R1, R2, R3, and R4; and at least one of them is selected from... At least one of R5, R6, and R7 is selected from "*" indicates a connection point.

[0026] In Equation III, R 11 R 12 R 13 Each is independently selected from H, substituted or unsubstituted C1-C6 straight-chain or branched alkyl groups, and substituted or unsubstituted C2-C6 straight-chain or branched alkenyl groups; the substituted substituents include any one of halogen, -OH, and -COOH.

[0027] In this invention, C2-C6 straight-chain or branched alkenyl groups refer to straight-chain or branched alkenyl groups with 2-6 carbon atoms, such as C2, C3, C4, C5, and C6; exemplary examples include, but are not limited to, vinyl, propenyl, and n-butenyl groups. The same expressions used below have the same meaning.

[0028] Preferably, in formula III, R 11 R 12 R 13 Each is independently selected from methyl groups.

[0029] Preferably, the photoacid-producing agent includes at least one of iodonium salts, thiodonium salts, imide sulfonates, oxime sulfonates, and triazine compounds.

[0030] In this invention, the anions in the photo-induced acid-producing agent include perfluoroalkyl sulfonates, aromatic sulfonates, etc.; the cations contain a benzene ring structure, and the substituents on the benzene ring include methoxy, tert-butyl, etc.

[0031] Preferably, the photoacid-producing agent includes at least one of the following compounds.

[0032]

[0033]

[0034] Preferably, the positive photoresist composition further includes 200 to 2000 parts of solvent by weight, for example, 200 parts, 400 parts, 600 parts, 800 parts, 1000 parts, 1200 parts, 1400 parts, 1600 parts, 1800 parts, 2000 parts, etc.

[0035] In this invention, the solvent can be any organic solvent capable of dissolving each component without reacting with it; exemplary, the solvent includes, but is not limited to, ethylene glycol, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether, benzyl alcohol, n-butyl acetate, methyl methoxypropionate, ethyl lactate, ethyl ethoxypropionate, diethylene glycol methyl ethyl ether, acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, toluene, xylene, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, etc.

[0036] Preferably, the positive photoresist composition further comprises, by weight, 0.01 to 0.1 parts of surfactant (e.g., 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, etc.) and / or 0.001 to 0.05 parts of organic base (e.g., 0.001, 0.002, 0.004, 0.006, 0.008, 0.01, 0.02, 0.03, 0.04, 0.05, etc.).

[0037] Preferably, the organic base comprises a nitrogen-containing compound; the nitrogen-containing compound comprises at least one of amine compounds, alkanolamine compounds, urea and its derivatives, amide compounds, and nitrogen heterocyclic compounds; exemplaryly, the organic base comprises aromatic amines, triethanolamine, formamide, urea, methylurea, tris(3,6-dioxaheptyl)amine, imidazole, benzimidazole, N-(tert-butoxycarbonyl)piperidine, N-(tert-butoxycarbonyl)imidazol, N-(tert-butoxycarbonyl)benzimidazole, and N-(tert-butoxycarbonyl)-2-phenylbenzimidazole.

[0038] In this invention, the surfactants include, but are not limited to, fluorinated surfactants, polysiloxane surfactants, and ammonium salt surfactants.

[0039] In this invention, the fluorinated surfactants include, but are not limited to, sodium perfluorododecanesulfonate, 1,1,2,2,8,8,9,9,10,10-decafluorododecane, diglyceride tetra(fluoroalkyl polyoxyethylene ether), perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, fluoroalkyl carboxylate ester, sodium perfluorododecanesulfonate, hexaethylene glycol di(1,1,2,2,3,3-hexafluoro-n-pentyl) ether, octaethylene glycol di(1,1,2,2-tetrafluoro-n-butyl) ether, etc.; the polysiloxane surfactants include, but are not limited to, polyether siloxane copolymers, polyester-modified polydimethylsiloxane copolymers, etc.; the ammonium salt surfactants include, but are not limited to, alkyl diphenyl ether disulfonate ammonium, alkyl diphenyl ether sulfonate ammonium, alkylbenzene sulfonate ammonium, polyoxyethylene alkyl ether ammonium sulfate, alkyl sulfate ammonium salt, etc.

[0040] Preferably, the positive photoresist composition further includes 5 to 20 parts by weight of a solubility promoter, such as 5, 6, 8, 10, 12, 14, 16, 18, or 20 parts.

[0041] Preferably, the dissolution promoter has the structure shown in Formula IV.

[0042]

[0043] In Formula IV, R is selected from any one of H, substituted or unsubstituted C1-C6 straight-chain or branched alkyl groups, substituted or unsubstituted C6-C30 aryl groups, and substituted or unsubstituted C3-C30 heteroaryl groups.

[0044] R1, R2, and R3 are each independently selected from any one of -OH, substituted or unsubstituted C1-C6 straight-chain or branched alkyl groups, substituted or unsubstituted C6-C30 aryl groups, substituted or unsubstituted C6-C30 arylalkyl groups, substituted or unsubstituted C3-C30 heteroaryl groups, and substituted or unsubstituted C3-C30 heteroarylalkyl groups.

[0045] The substituents include at least one of halogen, hydroxyl, amino, and carboxyl groups.

[0046] Furthermore, at least one of R1, R2, and R3 is selected from any one of -OH, -OH-substituted C1-C6 straight-chain or branched alkyl, -OH-substituted C6-C30 aryl, -OH-substituted C6-C30 arylalkyl, -OH-substituted C3-C30 heteroaryl, and -OH-substituted C3-C30 heteroarylalkyl.

[0047] n1, n2, and n3 are each independently selected from integers from 0 to 5, for example, they can be 0, 1, 2, 3, 4, 5, etc.; and at least one of n1, n2, and n3 is not selected from 0.

[0048] In this invention, C6 to C30 all refer to the number of carbon atoms being 6 to 30, for example, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.

[0049] In this invention, C3 to C30 all refer to the number of carbon atoms being 3 to 30, for example, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.

[0050] In this invention, the C6-C30 aryl group can be a fused-ring aryl group or a monocyclic aryl group. Exemplarily, the C6-C30 aryl group includes, but is not limited to, phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthryl, indene, fluorenyl, fluoranyl, triphenylene, pyrene, perylene, and tetraphenyl, etc.; the same expressions in the following text have the same meaning.

[0051] In this invention, the C3-C30 heteroaryl group can be a fused-ring heteroaryl group or a monocyclic heteroaryl group; exemplaryly, the C3-C30 heteroaryl group includes, but is not limited to, furanyl, thiophene, pyrrole, pyridyl, benzofuranyl, benzothiophene, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothiophene, carbazole, acridineyl, isobenzofuranyl, isobenzothiophene, benzocarbazole, etc.; the same expressions below have the same meaning.

[0052] In this invention, the C6-C30 arylalkyl and C3-C30 heteroarylalkyl refer to groups formed by replacing at least one H in the aforementioned aryl or heteroaryl groups with an alkyl group; the linking site can be on the aryl or heteroaryl group or on the alkyl group, and the number of carbon atoms in the alkyl group can be 1 to 10, for example, 2, 4, 6, 8, etc.; the same expression in the following text has the same meaning.

[0053] Preferably, the dissolution promoter has the structure shown in Formula IV-1.

[0054]

[0055] In Equation IV-1, R1, R2, and R3 are each independently selected from the same range of limitations as R1, R2, and R3 in Equation IV.

[0056] Preferably, the dissolution promoter comprises at least one of the following compounds.

[0057]

[0058] In a second aspect, the present invention provides a method for preparing the positive photoresist composition described in the first aspect, the method comprising: uniformly mixing a modified phenolic resin, a diazonaphthoquinone compound, a photoacid-generating agent, and optionally a solvent, a surfactant, an organic base, and a solubilizer to obtain the positive photoresist composition.

[0059] In a second aspect, the present invention provides the application of the positive photoresist composition described in the first aspect in the preparation of an organic light-emitting diode display panel.

[0060] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0061] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0062] The positive photoresist composition provided by this invention includes a modified phenolic resin with a molecular structure containing the structure shown in Formula I. That is, by protecting the phenolic hydroxyl groups in the phenolic resin with low activation energy through acetal or ketal treatment to different degrees, and by combining a photoacid-generating agent and a diazonoquinone compound, the resolution and photosensitivity of the photoresist are improved while ensuring a low residual film rate. At the same time, the PEB process is not required, and its morphology after development is not affected by trace amounts of alkali in the air, thus meeting the industry requirements of low cost and high performance. Detailed Implementation

[0063] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof. In the present invention, the content of each component in the positive photoresist composition refers to the effective content; for example, 100 parts of modified phenolic resin refers to the effective content of the modified phenolic resin, i.e., excluding the mass of the solvent.

[0064] Example 1

[0065] This embodiment provides a positive photoresist composition, which, by weight, comprises 100 parts of modified phenolic resin (the modified phenolic resin contains a structure with a molar percentage of 22%). The modified phenolic resin has a Mw of 5800, 5 parts of PAC (TPPA-PAC, α,α,α'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzenediazonaphthoquinone sulfonate, esterification rate 2.5 mol), and 0.05 parts of PAG. 0.05 parts surfactant (DIC Corporation F554), 0.02 parts organic base tris(3,6-dioxaheptyl)amine, 12 parts solubility accelerator And 400 parts of solvent PGMEA.

[0066] This embodiment provides a method for preparing a positive photoresist composition, specifically including the following steps:

[0067] The modified phenolic resin, PAC, PAG, surfactant, organic base, solubilizer and solvent are mixed evenly to obtain the photoresist composition.

[0068] The method for preparing the modified phenolic resin includes: using Sumitomo linear phenolic resin from Japan, with a meta / para substitution ratio of meta / para = 5 / 5 and Mw = 5000; dissolving 40.0 g of the unprotected phenolic resin in 160.0 g of methyl isobutyl ketone (MIBK) solvent; and adding dihydropyran (DHP) (the amount of DHP added is such that...). The molar percentage of phenolic hydroxyl groups was 22%, i.e., 22 mol% of phenolic hydroxyl groups were protected. The mixture was stirred until homogeneous, and then 0.2 g of trifluoroacetic acid in MIBK solution was added dropwise at room temperature. The mixture was stirred continuously for 5 hours. After the reaction was completed, an appropriate amount of triethylamine was added to neutralize the trifluoroacetic acid catalyst. The reaction solution was then poured into pure water and thoroughly shaken to mix. The mixture was allowed to stand and separate into layers. The organic phase was then subjected to vacuum distillation and solvent replacement to obtain a PGMEA solution of modified phenolic resin. The molecular weight (Mw) was determined to be 5800 by GPC.

[0069] Example 2

[0070] This embodiment provides a positive photoresist composition, which, by weight, comprises 100 parts of modified phenolic resin (the modified phenolic resin contains a structure with a molar percentage of 25%). Mw is 4300), 3 parts PAC (TPPA-PAC, esterification rate 2.5mol), 0.08 parts PAG 0.02 parts surfactant (DIC Corporation F554), 0.01 parts organic base tris(3,6-dioxaheptyl)amine, 8 parts solubility accelerator 400 parts of solvent PGMEA.

[0071] The preparation method of the positive photoresist composition is the same as in Example 1; wherein, the preparation method of the modified phenolic resin includes: using Sumitomo linear phenolic resin (meta / para = 5 / 5, Mw = 3800), dissolving 40.0g of the unprotected phenolic resin in 160.0g of MIBK solvent, and adding dihydrofuran (DHF) (the amount of DHF added is such that...). The molar percentage of phenolic hydroxyl groups was 25%, i.e., 25 mol% of phenolic hydroxyl groups were protected. The mixture was stirred until homogeneous, and then 0.2 g of trifluoroacetic acid in MIBK solution was added dropwise at room temperature. The mixture was stirred continuously for 5 hours. After the reaction was completed, an appropriate amount of triethylamine was added to neutralize the trifluoroacetic acid catalyst. The reaction solution was then poured into pure water and thoroughly shaken to mix. The mixture was allowed to stand and separate into layers. The organic phase was then subjected to vacuum distillation and solvent replacement to obtain a modified phenolic resin PGMEA solution. The Mw value was measured to be 4300 by GPC.

[0072] Example 3

[0073] This embodiment provides a positive photoresist composition, which, by weight, comprises 100 parts of modified phenolic resin (the modified phenolic resin contains a structure with a molar percentage of 28%). Mw is 5300), 2 parts PAC (TPPA-PAC, esterification rate 2.5mol), 0.09 parts PAG 0.08 parts surfactant (DIC Corporation F554), 0.001 parts organic base tris(3,6-dioxaheptyl)amine, 18 parts solubility accelerator And 400 parts of solvent PGMEA.

[0074] The preparation method of the positive photoresist composition is the same as in Example 1; wherein, the preparation method of the modified phenolic resin includes: using Sumitomo linear phenolic resin (meta / para = 5 / 5, Mw = 4500), dissolving 40.0g of the unprotected phenolic resin in 160.0g of MIBK solvent, and adding dihydrofuran (DHF) (the amount of DHF added is such that...). The molar percentage of phenolic hydroxyl groups was 28%, i.e., 28 mol% of phenolic hydroxyl groups were protected. The mixture was stirred evenly, and then 0.2 g of trifluoroacetic acid MIBK solution was added dropwise at room temperature. The mixture was stirred continuously for 5 hours. After the reaction was completed, an appropriate amount of triethylamine was added to neutralize the trifluoroacetic acid catalyst. The reaction solution was then poured into pure water and thoroughly shaken to mix evenly. The mixture was allowed to stand and separate into layers. The organic phase was taken for vacuum distillation and solvent replacement to obtain a modified phenolic resin PGMEA solution. The Mw value was measured to be 5300 by GPC.

[0075] Example 4

[0076] This embodiment provides a positive photoresist composition, which differs from Example 1 in that the modified phenolic resin contains a structure with a molar percentage of 15%. The other components, dosages, and preparation methods are the same as in Example 1; however, the amount of DHP added in the preparation method of the modified phenolic resin is adjusted to... The molar percentage content should be 15%.

[0077] Example 5

[0078] This embodiment provides a positive photoresist composition, which differs from Example 1 in that the modified phenolic resin contains a structure with a molar percentage of 35%. The other components, dosages, and preparation methods are the same as in Example 1; however, the amount of DHP added in the preparation method of the modified phenolic resin is adjusted to... The molar percentage content should be 35%.

[0079] Example 6

[0080] This embodiment provides a positive photoresist composition, which differs from Example 1 in that the modified phenolic resin contains a structure with a molar percentage of 8%. The other components, dosages, and preparation methods are the same as in Example 1; however, the amount of DHP added in the preparation method of the modified phenolic resin is adjusted to... The molar percentage content should be 8%.

[0081] Example 7

[0082] This embodiment provides a positive photoresist composition, which differs from Example 1 in that the modified phenolic resin contains a structure with a molar percentage of 45%. The other components, dosages, and preparation methods are the same as in Example 1; however, the amount of DHP added in the preparation method of the modified phenolic resin is adjusted to... The molar percentage content should be 45%.

[0083] Example 8

[0084] This embodiment provides a positive photoresist composition, which differs from Example 1 in that the modified phenolic resin contains a structure with a molar percentage of 22%. The other components, dosages, and preparation methods are the same as in Example 1; however, in the preparation method of the modified phenolic resin, DHP is replaced with vinyl ethyl ether (EVE), and the amount added is such that... The molar percentage content should be 22%.

[0085] Example 9

[0086] This embodiment provides a positive photoresist composition, which differs from Example 1 only in that the modified phenolic resin has a Mw of 1500, and the modified phenolic resin is prepared by using a linear phenolic resin with a corresponding Mw (m / p = 5 / 5) so that the final modified phenolic resin has a Mw of 1500; the amounts of other components and the preparation methods are the same as in Example 1.

[0087] Example 10

[0088] This embodiment provides a positive photoresist composition, which differs from Example 1 only in that the Mw of the modified phenolic resin is 13000, and the preparation method of the modified phenolic resin uses a linear phenolic resin with a corresponding Mw (m / p = 5 / 5) so that the Mw of the final modified phenolic resin is 13000; the dosage of other components and the preparation method are the same as in Example 1.

[0089] Comparative Example 1

[0090] This comparative example provides a positive photoresist composition, which differs from Example 1 only in that the modified phenolic resin contains a structure with a molar percentage of 22%. The other components, dosages, and preparation methods are the same as in Example 1; however, in the preparation method of the modified phenolic resin, DHP is replaced with tert-butanol, and the amount added is such that... The molar percentage content should be 22%.

[0091] Comparative Example 2

[0092] This comparative example provides a photoresist composition that differs from Example 1 only in that the mass of the PAC is 0.1 parts, and the type is 2,3,4,4'-tetrahydroxybenzophenone 1,2-diazidonaphthoquinone-5-sulfonate (photoinitiator 4215). The other components, amounts, and preparation methods are the same as in Example 1.

[0093] Comparative Example 3

[0094] This comparative example provides a photoresist composition that differs from Example 1 only in that the mass of the PAC is 11 parts, the type is photoinitiator 4215, and the other components, amounts, and preparation methods are the same as in Example 1.

[0095] Comparative Example 4

[0096] This comparative example provides a photoresist composition that differs from Example 1 only in that the mass of PAG is 0.3 parts, while the other components, amounts, and preparation methods are the same as in Example 1.

[0097] Comparative Example 5

[0098] This comparative example provides a photoresist composition that differs from Example 1 only in that the mass of PAG is 0.005 parts, while the other components, amounts, and preparation methods are the same as in Example 1.

[0099] Performance testing

[0100] The photoresist compositions provided in the examples and comparative examples were coated onto the surface of a silicon wafer at a rotation speed of 1000 rpm and preheated at 110°C for 150 s to obtain a photoresist film with a thickness of 1.5 μm (measured by a white light interferometer). Exposure was performed using an MPA series scanning projection exposure machine with a scanning time of 25 s and a grayscale mask of 5%–100%. The film was then developed in a 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution at 23°C for 60 s, followed by rinsing with ultrapure water to obtain the photolithographic pattern. The exposure energy corresponding to the area that was just developed was defined as the sensitivity. The thickness of the unexposed area was measured using a white light interferometer, and the difference from the initial thickness was defined as the dark loss. The minimum line that the photoresist could open, detected using a Hitachi S4800, was defined as the resolution.

[0101] Where, Dark loss < 0.14um

[0102] Sensitivity <50mj / cm 2

[0103] Resolution <1.3um.

[0104] The specific test results are shown in Table 1.

[0105] Table 1

[0106]

[0107]

[0108] As shown in Table 1, the positive photoresist composition provided by this invention, by protecting the phenolic hydroxyl groups in the phenolic resin with low activation energy through acetal or ketal formation to varying degrees, and by combining specific amounts of photoacid-producing agents and diazonoquinone compounds, improves the resolution and photosensitivity of the photoresist while ensuring a low residual film rate. Furthermore, it eliminates the need for a PEB process, and its morphology after development is unaffected by trace amounts of alkali in the air, meeting the industry requirements of low cost and high performance. The photoresist composition exhibits a dark loss of <0.14µm and a sensitivity of <50mJ / cm. 2 Resolution <1.3um.

[0109] As can be seen from Examples 1, 4-7, the molar percentage content of the structure shown in Formula I in the modified phenolic resin is within a specific range, which is beneficial for the photoresist composition to achieve both low dark loss, high resolution, and high sensitivity.

[0110] As shown in Comparative Example 1, when tert-butyl groups are used to protect the phenolic hydroxyl groups, exposure is not possible under the same conditions.

[0111] As can be seen from Comparative Examples 2 and 3, if the PAC content is too low, the resolution decreases and the dark loss increases; if the content is too high, the sensitivity decreases.

[0112] As can be seen from Comparative Examples 4 and 5, when the PAG content is too high, the transmittance is insufficient and the bottom cannot be exposed; when it is too low, the acid generated during exposure cannot completely catalyze the deprotection of the protective groups.

[0113] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A positive photoresist composition, characterized by comprising: The positive photoresist composition comprises 100 parts of a modified phenol formaldehyde resin, 0.5 to 10 parts of a diazonium naphthoquinone compound, and 0.01 to 0.1 parts of a photo-acid generator, by weight; The modified phenol formaldehyde resin comprises a structure represented by Formula I in a molecular structure thereof; wherein R1is selected from R 11 , R 12 each independently selected from C1-C6 linear or branched alkyl; R 11 , R 12 is not connected or is connected by a chemical bond into a ring; "*" indicates the connection site; R2 is selected from a C1 to C6 linear or branched alkyl group; n1 is an integer selected from 0 to 3; n≥1。 2. The positive photoresist composition according to claim 1, wherein said R1 is selected from the group consisting of more preferably R1 is selected from the group consisting of "*" represents a connection site; Preferably, R2 is selected from a methyl group.

3. The positive photoresist composition according to claim 1 or 2, characterized by The modified phenol formaldehyde resin has a molar percentage content of the structure represented by Formula I of 5 to 50%, preferably 20 to 34%, and particularly preferably 21 to 29%; Preferably, the modified phenol formaldehyde resin has a weight average molecular weight of 2,000 to 10,000.

4. The positive photoresist composition according to any one of claims 1 to 3, characterized in that, The diazonium naphthoquinone compound comprises a compound having a structure represented by Formula II and / or a compound having a structure represented by Formula III; wherein R1, R2, R3, R4, R5, R6, R7are each independently selected from H, R1, R2, R3, R4, R5, R6, R7are each independently selected from H, R5, R6, R7are each independently selected from H, "*" indicates the point of attachment; In Formula III, R 11 , R 12 , R 13 each is independently selected from any one of H, substituted or unsubstituted C1-C6 straight chain or branched alkyl, substituted or unsubstituted C2-C6 straight chain or branched alkenyl; the substituted substituent includes any one of halogen, -OH, -COOH; Preferably, in Formula III, R1, R2, and R3 are each independently selected from a methyl group.

5. The positive photoresist composition according to any one of claims 1 to 4, characterized in that, The photo-acid generator comprises at least one of an iodonium salt, a sulfonium salt, an imide sulfonate compound, an oxime sulfonate compound, and a triazine compound; Preferably, the photo-acid generator comprises at least one of the following compounds:

6. The positive photoresist composition according to any one of claims 1 to 5, characterized in that, The positive photoresist composition further comprises 200 to 2,000 parts of a solvent, by weight.

7. The positive photoresist composition according to any one of claims 1 to 6, characterized in that, The positive photoresist composition further comprises 0.01 to 0.1 parts of a surfactant and / or 0.001 to 0.05 parts of an organic base, by weight.

8. The positive photoresist composition according to any one of claims 1 to 7, characterized in that, The positive photoresist composition further comprises 5 to 20 parts of a dissolution promoter, by weight. Preferably, the dissolution promoter has a structure represented by Formula IV; In Formula IV, R is selected from any one of H, a substituted or unsubstituted C1 to C6 linear or branched alkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C3 to C30 heteroaryl group; R1, R2, and R3 are each independently selected from any one of -OH, a substituted or unsubstituted C1 to C6 linear or branched alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C6 to C30 arylalkyl group, a substituted or unsubstituted C3 to C30 heteroaryl group, and a substituted or unsubstituted C3 to C30 heteroarylalkyl group; The substituted substituent includes at least one of a halogen, a hydroxyl group, an amino group, and a carboxyl group; and at least one of R1, R2, and R3 is selected from any one of -OH, a -OH substituted C1 to C6 linear or branched alkyl group, a -OH substituted C6 to C30 aryl group, a -OH substituted C6 to C30 arylalkyl group, a -OH substituted C3 to C30 heteroaryl group, and a -OH substituted C3 to C30 heteroarylalkyl group; n1, n2, and n3 are each independently an integer selected from 0 to 5, and at least one of n1, n2, and n3 is not 0; Preferably, the dissolution promoter has a structure represented by Formula IV-1; In Formula IV-1, R1, R2, and R3 are each independently selected from the same defined range as R1, R2, and R3 in Formula IV; Preferably, the dissolution promoter comprises at least one of the following compounds:

9. A method for producing the positive photoresist composition according to any one of claims 1 to 8, characterized by, The preparation method comprises: The modified phenolic resin, the diazonium naphthoquinone compound and the photoacid generator are mixed with optional solvent, surfactant, organic base, dissolution promoter to obtain the positive photoresist composition.

10. Use of the positive photoresist composition according to any one of claims 1-8 in the preparation of an organic light emitting diode display panel.

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