Negative photoresist based on POSS hyperbranched structure acrylate resin

Abstract

The invention belongs to the technical field of photoresists, and particularly relates to a negative photoresist based on POSS (polyhedral oligomeric silsesquioxane) hyperbranched structure acrylate resin, which comprises the POSS hyperbranched structure acrylate resin, a free radical polymerization initiator, an ethylenic bond-containing unsaturated compound, a surfactant and an adhesion promoter, the POSS hyperbranched structure acrylate resin has a structure as shown in a general formula II, wherein n is greater than or equal to 1. According to the invention, POSS is taken as a core, acrylate resin with a POSS hyperbranched structure is prepared through free radical addition reaction, the acrylate resin is used as matrix resin of negative photoresist, and an organic insulating film with high process yield, low manufacturing cost, good light transmission, high flatness, excellent pattern stability, low dielectric constant and good adhesion with a matrix layer can be formed.

Description

TECHNICAL FIELD

[0001] The application relates to a negative photoresist based on a POSS hyperbranched structure acrylate resin and belongs to the technical field of photoresists. BACKGROUND

[0002] Photoetching technology plays an important role in the manufacturing of microelectronic devices such as integrated circuits (IC), large-scale integrated (LSI) devices, liquid crystal devices (LCD) and light emitting diodes (LED).

[0003] In recent years, the circuit element density of semiconductors has rapidly increased by about two times every three years, and such rapid technical progress is mainly realized by improving the resolution of photoresists and light exposure tools. Among them, the photoresist is a key material for building a multi-layer electronic device complex through a manufacturing process.

[0004] The thin film transistor liquid crystal display (TFT-LCD) is a commonly used technology for display panels at present, which improves the quality of product images. The main design feature of the TFT-LCD is that the relatively independent pixel points can be continuously controlled, which improves the response speed of the display screen and can realize accurate control of display.

[0005] In the TFT-LCD, electrodes are arranged on the upper and lower surfaces of the organic insulating film layer, and the pixel electrode and the signal line electrode are arranged in different layers to improve the aperture ratio of the TFT-LCD. At this time, the pixel electrode is arranged on the gate line to form a storage capacitor. When the photoresist composition of the conventional polyacrylic acid-based and polyimide-based adhesive resin forms the organic insulating film, the dielectric constant is relatively large, and the adhesion to the substrates such as metal, glass and silicon is poor, and the residual film rate after development is low, resulting in poor flatness of the pattern. The low dielectric constant organic insulating film is crucial for reducing the parasitic capacitance between the pixel electrode and the wiring. Therefore, a photoresist made of an organic insulating film main resin suitable for a low dielectric constant is needed to solve the above problems. SUMMARY

[0006] The application provides a negative photoresist based on a POSS hyperbranched structure acrylate resin to solve the above technical problems.

[0007] The technical scheme for solving the above technical problems is as follows:

[0008] A negative photoresist based on a POSS hyperbranched acrylate resin comprises a POSS hyperbranched acrylate resin, a free radical polymerization initiator, an unsaturated compound containing olefin bonds, a surfactant, and an adhesion promoter; the POSS hyperbranched acrylate resin has the structure shown in general formula II:

[0009]

[0010] Where n≥1;

[0011] The R group contains a methyl group, or contains 1 to 30 -CH2 groups, or the R group is an aromatic group or its derivative, or the R group has a polyacrylate structure;

[0012] The terminal group of the R group contains a reactive functional group, wherein the reactive functional group is any one of hydroxyl, carboxyl, epoxy, amino or C=C;

[0013] X is one of O, NH or S;

[0014] a, b, and c are constants ranging from 1 to 30;

[0015] R1 is -OR', -NR'2 or -SR', or R1 is an alkyl, hydroxyalkyl or alkyl chain with 1 to 15 carbon atoms, or R1 is an olefinic group with 2 to 15 carbon atoms containing a double bond;

[0016] R' is selected from any of the following structures and their derivative structures:

[0017]

[0018] Where m ≥ 1; R4 is hydrogen or methyl;

[0019] Both R1 and R2 have at least one reactive functional group II at their end groups, wherein the reactive functional group II is any one of hydroxyl, carboxyl, epoxy, amino, or C=C.

[0020] R2 is a carboxyl group or its derivative, or an alkyl group, hydroxyalkyl group, alkyl chain with an epoxy group or aromatic derivative having 1 to 15 carbon atoms, or any one of hydrogen or heterocyclic group;

[0021] R3 is any one or two of the following groups: phenyl or its derivative, pyridyl or its derivative, cyclohexyl or its derivative, pyrazolyl or its derivative, imidazole or its derivative, triazine or its derivative, triazolyl or its derivative, hydrogen, methyl, carboxyl or dioxane.

[0022] Based on the above technical solution, the present invention can also be improved as follows:

[0023] Furthermore, the raw materials used to synthesize the POSS hyperbranched acrylate resin are polyfunctional oligomeric silsesquioxanes, (meth)acrylate monomers, and monomers containing R3 groups with ethylene unsaturated bonds.

[0024] Furthermore, the structure of the multifunctional oligomeric silsesquioxane is selected from the following general formula I:

[0025]

[0026] Among them, the R0 group contains a methyl group, or contains 1 to 20 -CH2 groups, or the R0 group is an aromatic group or its derivative, or the R0 group is one or more of polyether, polyamide, and polyamide-amine;

[0027] The terminal group of R0 contains at least three reactive functional groups, wherein the reactive functional group is any one of hydroxyl, carboxyl, epoxy, amino, ester, aldehyde, carbonyl, alkenyl, aromatic unsaturated group or its derivative.

[0028] n≥1.

[0029] Furthermore, the (meth)acrylate monomers are any one or more of the following: 2-hydroxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, diethylene glycol monoethyl ether (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol (meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentadienol (meth)acrylate, pentyltetra(meth)acrylate, ethyl 2-(acryloyloxy)benzoate, ethyl 2-(methacryloyloxy)benzoate, α,β-unsaturated (meth)carboxylic acid esters, and β-hydroxypropyl (meth)acrylate.

[0030] Furthermore, the monomer containing the R3 group and having an ethylene unsaturated bond is one or more of the following: (meth)acrylates or their derivatives, maleic acid or its derivatives, norbornene and its derivatives, styrene, styrene and its derivatives, styrene-cinnamic acid derivatives, etc.

[0031] Furthermore, the initiator used to synthesize the POSS hyperbranched acrylate resin is an azo photoinitiator or an acetophenone compound, wherein the acetophenone compound is an α-amino ketone compound or an α-hydroxy ketone compound.

[0032] Furthermore, the azo photoinitiator is any one of 2,2'-azobis(2,4-dimethylpentanonitrile), 2,2'-azobis(2-methylbutanonitrile), 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], 2,2'-azobis(2-methylbutanonitrile), 2,2'-azobis[2-(2-imidazolin-2-yl)propane], 1,1,1-tris(p-hydroxyphenyl)ethane, and 1,2-naphthoquinone diazido-5-sulfonyl chloride condensate.

[0033] Further, the acetophenone compound is an α-amino ketone compound or an α-hydroxy ketone compound. The α-amino ketone compound is any one of 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butane-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholino-4-ylphenyl)-butane-1-one, or 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one; the α-hydroxy ketone compound is preferably any one of 1-phenyl-2-hydroxy-2-methylpropane-1-one, 1-(4-dipropylphenyl)-2-hydroxy-2-methylpropane-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)one, or 1-hydroxycyclohexylphenyl ketone.

[0034] Furthermore, the chain transfer agent used to synthesize the POSS hyperbranched acrylate resin is a thiol compound, which is an aromatic thiol compound or an aliphatic monothiol compound.

[0035] Furthermore, the aromatic thiol compound is any one of 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, or 2-mercapto-5-methoxybenzothiazole; the aliphatic monothiol compound is any one of 3-mercaptopropionic acid, methyl 3-mercaptopropionate, pentaerythritol tetra(mercaptoacetate), or pentaerythritol tetra(3-mercaptopropionate).

[0036] Furthermore, the solvent used to synthesize the POSS hyperbranched acrylate resin is a protic organic solvent such as an alcohol or an aprotic organic solvent. The aprotic organic solvent is one or more of the following: N,N-dimethylformamide (DMF), N,N-diethylformamide, N-methylpyrrolidone (NMP), N-ethylpyrrolidone, tetrahydrofuran, ethyl acetoacetate, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, methyl acrylate, propyl acrylate, methylcellulose, ethylcellulose, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate (PMA), methyl isobutyl ketone, cyclohexanone, dimethoxyformamide, N,N-dimethylacetamide, γ-butyrolactone, 1,4-dioxane, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and dipropylene glycol monomethyl ether.

[0037] Furthermore, the synthesis temperature for synthesizing the POSS hyperbranched acrylate resin is 10–150°C, preferably 30–120°C, more preferably 50–100°C; the synthesis time is 1–48 h, preferably 2–24 h, more preferably 4–12 h.

[0038] Furthermore, the molecular weight of the POSS hyperbranched acrylate resin was determined using GPC (gel dialysis chromatography) with tetrahydrofuran as the mobile phase. The average molecular weight (based on polystyrene) was between 2000 and 40000, the dispersity was between 1.0 and 4.0, and the acid value was between 60 and 150 mg KOH / g.

[0039] Furthermore, the negative photoresist based on POSS hyperbranched acrylate resin of the present invention comprises, by weight, 50-100 parts of POSS hyperbranched acrylate resin, 0.01-20 parts of free radical polymerization initiator, 10-50 parts of unsaturated compound containing olefin bonds, 0.01-5 parts of surfactant, 0.01-5 parts of adhesion promoter and 100-2000 parts of solvent.

[0040] Furthermore, the free radical polymerization initiator includes any one or a combination of two or more of acyl oxime compounds, acetophenone compounds, and biimidazole compounds.

[0041] Further, the acyl oxime compound is selected from acetone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-aminoazol-3-yl]-1-(O-acetyl oxime), 1-[9-ethyl-6-benzoyl-9H-carbazole-3-yl]octane-1-oxime-O-acetate, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethane-1-formoxime-O-benzoate, 1-[9-n-butyl-6-(2-ethylbenzoyl)-9H-aminoazol-3-yl]ethane-1-benzoate, acetone-1-[9-ethyl-6-(2-methyl-4-tetrahydrofuran] Any one of the following: [9-ethyl-6-ethanetanyl-1-[9-ethyl-6-(2-methyl-5-tetrahydrofuranylbenzoyl)-9H-piperazol-3-yl]-1-(O-acetyl oxime), [9-ethyl-6-(2-methyl-5-tetrahydrofuranylbenzoyl)-9H-furan-3-yl]-1-(O-acetyl oxime), [9-ethyl-6-(2-methyl-5-tetrahydrofuranylbenzoyl)-9H-furan-3-yl]-1-(O-acetyl oxime), [9-ethyl-6-(2-methyl-4-tetrahydrofuranylmethoxybenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime).

[0042] Further, the acetophenone compound is preferably an α-amino ketone compound or an α-hydroxy ketone compound. The α-amino ketone compound includes any one of 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butane-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholino-4-ylphenyl)-butane-1-one, or 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one; the α-hydroxy ketone compound is preferably any one of 1-phenyl-2-hydroxy-2-methylpropane-1-one, 1-(4-dipropylphenyl)-2-hydroxy-2-methylpropane-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)one, or 1-hydroxycyclohexylphenyl ketone.

[0043] Furthermore, the biimidazole compound is selected from any one of 2,2'-bis(2-chlorophenyl)-4,4',5'-tetra(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5'-tetraphenyl-1,2'-biazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5'-tetraphenyl-1,2'-biazole, or 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5'-tetraphenyl-1,2'-biazole.

[0044] When biimidazole compounds are selected as free radical polymerization initiators, aliphatic or aromatic compounds having a dialkylamino group can be added as amino sensitizers. The amino sensitizer is preferably any one of 4,4'-bis(dimethylamino)benzophenone or 4,4'-bis(diethylamino)benzophenone, or a combination thereof.

[0045] When biimidazole compounds and amino sensitizers are used in combination, thiols can be added as hydrogen radical donors. The thiols are preferably aromatic thiols or aliphatic monothiols, with the aromatic thiols preferably being any one of 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, or 2-mercapto-5-methoxybenzothiazole; and the aliphatic monothiols preferably being any one of 3-mercaptopropionic acid or methyl 3-mercaptopropionate, pentaerythritol tetra(mercaptoacetate), or pentaerythritol tetra(3-mercaptopropionate). Biimidazole compounds generate imidazole radicals under the action of amino sensitizers, enhancing polymerization initiation ability. By adding thiols to a system where biimidazole compounds and amino sensitizers coexist, hydrogen radicals from the thiols are donated to the imidazole radicals, not only converting the imidazole radicals to neutral imidazoles but also generating a sulfur radical component with high polymerization initiation ability. Therefore, even with low irradiation doses, a hardened film with high frictional resistance can be formed.

[0046] When biimidazole compounds and amino sensitizers are used in combination, the preferred ratio of amino sensitizer to biimidazole compound is 0.1-50, more preferably 1-20. By increasing the mass ratio of amino sensitizer to biimidazole compound from 0.1 to 50, the curing reactivity of the polymer can be improved, and the abrasion resistance of the obtained cured film can be enhanced.

[0047] Furthermore, the unsaturated compound containing an olefin bond is any one or a combination of two or more acrylates having difunctional or polyfunctional groups.

[0048] By adding an unsaturated compound containing an olefinic bond to the composition, the photosensitivity of the composition is improved and sublimation is reduced, and the hardened film formed by the composition is further improved in terms of abrasion resistance and transparency.

[0049] The difunctional acrylate is preferably any one of diethylene glycol (meth)acrylate, dipropylene glycol (meth)acrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol diacrylate, and 1,9-nonanediol dimethacrylate.

[0050] The trifunctional acrylate is preferably any one of trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, or pentaerythritol trimethacrylate.

[0051] The unsaturated compound containing an olefin bond can also be an acrylate with more functional groups, such as any one of pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, or ethylene oxide-modified dipentaerythritol hexaacrylate.

[0052] Furthermore, the surfactant is any one or a combination of two or more of fluorinated surfactants, silicone surfactants, and nonionic surfactants.

[0053] Furthermore, the adhesion promoter is any one or a mixture of two or more of the following: trimethoxysilylbenzoic acid, γ-methacrylateoxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanate propyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, N-phenylaminopropyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. The adhesion promoter used in this invention can improve the adhesion to the substrate.

[0054] Furthermore, the solvents used in the negative photoresist of the present invention include high-boiling-point solvents with a boiling point of 180°C or higher at atmospheric pressure and low-boiling-point solvents with a boiling point of less than 180°C.

[0055] The high-boiling-point solvent has a boiling point of at least 180°C at atmospheric pressure, preferably 180°C to 250°C, and more preferably 190°C to 210°C. In the solvent of the present invention, the content of the high-boiling-point solvent is preferably 5%-60%, more preferably 10%-50%, and even more preferably 15%-40% (by weight of the solvent). Within the above ranges, a highly smooth film can be prepared during the coating process. The high-boiling-point solvent is selected from any one or a mixture of two or more of the following: γ-butyrolactone, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol diethyl ether, dipropylene glycol methyl ether acetate, N,N-dimethylformamide, N-methylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, ethyl acetone, isoprene, octanoic acid, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, ethyl carbonate, propylene carbonate, and benzoyl acetate. Preferably, in terms of developing performance, it can be one or more of γ-butyrolactone, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate and diethylene glycol monobutyl ether acetate.

[0056] The low-boiling-point solvent is compatible with the components of the above-mentioned photoresist composition but does not react with them, and has a boiling point of less than 180°C, preferably 100°C. The low-boiling-point solvent is selected from propylene glycol monomethyl ether acetate, cyclohexanone, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol n-propyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol n-propyl ether, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate. One or more of the following: esters, diethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, methyl ethyl ether, 2-heptanone, 3-heptanone, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl formate, isoamyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate, N,N-dimethylformamide, N-dimethylacetamide, 3-methoxybutanol, and cyclopentanone.

[0057] Furthermore, the negative photoresist based on POSS hyperbranched acrylate resin of the present invention also includes any one or a combination of two or more antioxidants, stabilizers, and free radical scavengers.

[0058] The beneficial effects of this invention are as follows: This invention uses a polyhedral oligomeric silsesquioxane (POSS) structure containing multiple functional groups as the core, and prepares an acrylate resin with a POSS hyperbranched structure via free radical addition reaction. This resin is used as the main resin for negative photoresists. During the preparation process, the hydrophilicity / hydrophobicity, temperature resistance, chemical resistance, and reactivity of the polymer molecules can be adjusted by modifying the type and number of functional groups introduced from the monomers, and by adjusting the chain length and the number of aromatic groups or cycloalkanes contained. This compound, after being combined with solvents, unsaturated monomers containing olefin bonds, free radical polymerization initiators, and other additives to prepare a photoresist composition, can form an organic insulating film on a substrate after spin coating, pre-baking, exposure, development, and post-baking. This organic insulating film has advantages such as high process yield, low manufacturing cost, good light transmittance, high flatness, excellent pattern stability, low dielectric constant, and good adhesion to the substrate layer. Detailed Implementation

[0059] The principles and features of the present invention are described below with reference to examples. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0060] Synthesis of polymers with the structure shown in Formula II (A)

[0061] Synthesis example 1

[0062] 4.61g of acrylic acid (Mr=86), 20.74g of methyl cinnamate (Mr=162), and 1.43g of octamethacrylate polyhedral oligomeric silsesquioxane (Mr=1432) were added to 100g of propylene glycol methyl ether acetate (PMA), along with 0.5g of 2,2'-azobis(2,4-dimethylpentanonitrile). The mixture was stirred, and the reaction temperature was raised to 60°C. Free radical copolymerization was carried out for 12 hours to obtain a POSS hyperbranched acrylate resin with polyhedral oligomeric silsesquioxane (POSS) as the core. Then, 45.46g of glycidyl methacrylate (Mr=142.06) was added, and the reaction temperature was raised to 120°C. After modifying the copolymer for 6 hours, a polyacrylate derivative with reactive C=C double bond functional groups at the end groups was obtained, which can be used as the main resin material for negative photoresists. A copolymer with an average molecular weight of 32,000, a molecular weight distribution of 2.5, and an acid value of 80 mg KOH / g was obtained.

[0063] Its synthesis process is as follows:

[0064]

[0065] in,

[0066] Synthesis example 2

[0067] 50.44 g of cyclohexyl methacrylate (Mr = 168.12), 44.48 g of 2-phenylacrylic acid (Mr = 148.16), and 10.83 g of pentabutyl-trimethacrylate polyhedral oligomeric silsesquioxane (Mr = 1083) were added to 170 g of DMF (N,N-dimethylformamide), along with 0.2 g of 2,2'-azoisobutyronitrile. The mixture was stirred, and the reaction temperature was raised to 80 °C. Free radical copolymerization was carried out for 20 h to obtain a POSS hyperbranched acrylate resin. Then, 21.31 g of glycidyl methacrylate (Mr = 142.06) was added, and the reaction temperature was raised to 100 °C. After modifying the above copolymer for 24 h, a polyacrylate derivative with reactive C=C double bond functional groups at the end groups was obtained, which can be used as the main resin material for negative photoresists. A copolymer with an average molecular weight of 10,500, a molecular weight distribution of 2.1, and an acid value of 130 mg KOH / g was obtained.

[0068] Its synthesis process is as follows:

[0069]

[0070] Synthesis example 3

[0071] 7.84 g of maleic anhydride (Mr = 98.06) and 8.08 g of octa-3-aminopropyl polyhedral oligomeric silsesquioxane (Mr = 808) were added to 200 g of N-methylpyrrolidone (NMP) and reacted for 2 h. Then, 11.16 g of N-((5-hydroxy-6-methylbicyclo[2.2.1]hept-2-yl)methyl)methacrylamide (Mr = 223.16) and 5.2 g of styrene (Mr = 104) and 0.15 g of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] were added, stirred, and the reaction temperature was raised to 100 °C. Free radical copolymerization was carried out for 3 h to obtain POSS hyperbranched acrylate resin, which can be used as the main resin material for positive photoresist. A copolymer with an average molecular weight of 2400, a polymer molecular weight distribution of 2.5, and an acid value of 105 mg KOH / g was obtained.

[0072] Its synthesis process is as follows:

[0073]

[0074] Examples of components in a negative photoresist composition

[0075] The components used to prepare the compositions of the examples and comparative examples are as follows:

[0076] Polymers with the structure shown in general formula II

[0077] A-1: Prepared from Synthetic Example 1;

[0078] A-2: Prepared from Synthetic Example 2;

[0079] A-3: Prepared from Synthetic Example 3;

[0080] Free radical polymerization initiators

[0081] Ethyl ketone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-aminoazol-3-yl]-1-(O-acetyl oxime), (Irgacure OXE-02, Ci ba spec i aty Chemi ca ls Co.,LTD.);

[0082] <C> Unsaturated compounds containing alkene bonds

[0083] C-1: Pentaerythritol triacrylate (A-TMM-3LMN, Shin-Nakamura Chemical Industry Co., Ltd.);

[0084] C-2: dipentaerythritol hexaacrylate (KAYARAD DPHA, Nippon Chemical Co., Ltd.);

[0085] C-3: Dipentaerythritol pentaacrylate;

[0086] <D> Surfactants

[0087] FZ-2122, Dow Corning Toray Si l icone;

[0088] <E> Adhesives

[0089] γ-isocyanate propyltriethoxysilane, Shin-Etsu;

[0090] <F> Solvent

[0091] (F1) Organic solvents (organic solvents with a vapor pressure of 0.1 mmHg or higher and less than 1 mmHg at 20°C)

[0092] F1-1: Ethylene glycol monobutyl ether (20℃, 0.76mmHg);

[0093] F1-2: Diethylene glycol methyl ethyl ether (20℃, 0.75mmHg);

[0094] (F2) Organic solvents (organic solvents with a vapor pressure of 1 mmHg or more and 20 mmHg or less at 20°C)

[0095] F2-1: Cyclohexanone (20℃, 3.4 mmHg);

[0096] F2-2: Propylene glycol monomethyl ether acetate (20℃, 3.75mmHg);

[0097] F2-3: Propylene glycol monomethyl ether (20℃, 6.7mmHg);

[0098] Example 1

[0099] 70g of polymer (A-1), 10g of polymer (A-2), 20g of polymer (A-3), 5g of free radical polymerization initiator (B), 2g of unsaturated compound (C-1), 3g of unsaturated compound (C-2), 2g of unsaturated compound (C-3), 0.5g of surfactant (D), and 1g of adhesive (E) synthesized in Synthesis Example 1 were added to a container, and then propylene glycol monomethyl ether solvent was added to make the solid component concentration 20% to prepare a negative photoresist composition.

[0100] Examples 2-11 and Comparative Examples 1-2

[0101] Examples 2-11 and Comparative Examples 1-2 were prepared in the same manner as in Example 1, except that the types and amounts of each component were changed as shown in Tables 1 and 2. Additionally, <-> in Tables 1 and 2 indicate that the corresponding component was not used.

[0102] Furthermore, in Comparative Examples 1-2, an adhesive resin (average molecular weight 10000) represented by Formula 3 was used instead of the polymer with the structure shown in Formula II of Example 1 above. Except that the composition and content of the composition varied according to the composition described in Table 2 below, a negative photoresist composition for organic insulating film was also manufactured using the same method.

[0103]

[0104] In Equation 3 above, p is 0.3, q is 0.2, and r is 0.5.

[0105] The negative photoresist compositions prepared using the examples and comparative examples described above were evaluated for the following performance characteristics.

[0106] I. Evaluation of the photosensitivity of negative photoresist compositions

[0107] On a silicon substrate, for Examples 1-11 and Comparative Examples 1-2, after each composition was coated using a spin coater, it was pre-baked at 100°C for 2 minutes using a hot plate to form a coating film with a thickness of 1.5 μm. For the obtained coating film, a Canon PLA±501F exposure unit (ultra-high pressure mercury lamp) was used to expose the silicon wafer under a mask with a pattern of 3.0 μm linewidth. By varying the exposure time, the unexposed material was removed by washing in a 2.38% (w / w) tetramethylammonium hydroxide (TMAH) solution at 25°C for 80 seconds. Then, it was washed in ultrapure water for 1 minute and dried to form a pattern on the silicon substrate. At this point, the spatial linewidth (lower portion) was 0.30 μm. The minimum required exposure was measured, and the photosensitivity is shown in Tables 1 and 2. When the minimum exposure is less than 200 (J / m²), the photosensitivity is... 2 When the aperture ratio is at a certain point, the photosensitivity is considered good. At this point, the aperture ratio is also considered good.

[0108] II. Evaluation of the refractive index of interlayer insulating films

[0109] A cured film was formed on a silicon substrate, and the refractive index of the cured film was obtained. The refractive index of the cured film was measured at 633 nm using Auto EL IV NIR II I. When the refractive index is higher than 1.50, the material is considered suitable for use as an interlayer insulating film.

[0110] III. Evaluation of the heat resistance of interlayer insulating films

[0111] A cured film was formed on a silicon substrate, and the thickness (T2) of the cured film was measured. Then, the silicon substrate with the cured film was further baked in a clean oven at 240°C, and the thickness (t2) of the cured film was measured again. The film thickness change rate {(t2-T2) / T2}×100% was calculated based on the further baking. The results are shown in Tables 1 and 2. When this value is less than or equal to 3%, the heat resistance is good. At this point, the flatness is also good.

[0112] IV. Evaluation of the transmittance of interlayer insulating film

[0113] Similar to the "Photosensitivity Evaluation" described above, a thin film was formed on a glass substrate. The resulting thin film was then exposed using a Canon PLA±501F exposure lamp (ultra-high pressure mercury lamp) to a cumulative irradiation dose of 3000 J / m². 2 After exposure, the film is heated at 220°C for 1 hour in a clean drying oven to obtain a cured film. The transmittance of the glass substrate with this cured film was measured using a spectrophotometer "TU-1810" (manufactured by Beijing General Analytic Instrument Co., Ltd.) in the wavelength range of 400-800 nm. The results are shown in Tables 1 and 2. When the minimum transmittance exceeds 95%, the light transmittance is good.

[0114] V. Evaluation of the dry etching resistance of the interlayer insulating film

[0115] A cured film was formed on a silicon substrate using a CDE-80N dry etching apparatus (manufactured by Sh ibaura Mechatronics Co., Ltd.). The etching gases were CF4 50 mL / min and O2 10 mL / min, with an output of 400 mW. Dry etching was performed for 90 seconds, and the film head was measured before and after the process. The results are shown in Tables 1 and 2. Good dry etching performance was observed when the film thickness reduction was less than 1.0 μm. At this point, the residual film yield was also good.

[0116] VI. Evaluation of the Adhesion of Interlayer Insulating Films

[0117] On a silicon substrate, for Examples 1-11 and Comparative Examples 1-2, after each composition was coated using a spin coater, it was pre-baked at 100°C for 2 minutes using a hot plate to form a coating film with a thickness of 1.5 μm. Then, it was further baked in a clean oven at 240°C to form a cured film. The adhesion properties of the material were then tested using a cross-cut adhesion test. When the film peeling rate of the material was less than 5%, the adhesion was considered good.

[0118] Table 1. Examples and their physical property test results

[0119]

[0120] Table 2 Comparative Examples and Their Physical Properties Test Table

[0121]

[0122] As can be seen from the results in Tables 1 and 2, the cured film formed by the negative photoresist composition of the present invention uses a polymer with the structure shown in Formula II. Compared with the negative photoresist composition formed by using only one of the polymers with the structure shown in Formula 3 in Table 2, it has the characteristics of good heat resistance, high transmittance and good dry etching properties.

[0123] This invention utilizes the stable nanoscale 3D structure, low dielectric constant, high transparency, and high reactivity of multifunctional POSS to form a POSS hyperbranched acrylate resin with (meth)acrylate monomers under the action of a catalyst. This resin is then used as the main resin for a negative photoresist. After coating, pre-baking, exposure, development, and post-baking, an organic insulating film material with a low dielectric constant is formed. This reduces the dielectric constant of the resin while maintaining good thermal stability, mechanical properties, and chemical properties. The resulting low-dielectric-constant material also meets the application requirements of insulating film materials. By designing and adjusting the type and number of functional groups in the monomers, this invention can effectively improve their adhesion to the substrate, while also improving the residual film yield, pattern flatness, and aperture ratio.

[0124] The above description is only a preferred embodiment of the present invention and is 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 negative photoresist based on a POSS hyperbranched acrylate resin, characterized in that, Including acrylate resins based on POSS hyperbranched structure, free radical polymerization initiators, unsaturated compounds containing olefin bonds, surfactants, and tackifiers; The POSS hyperbranched acrylate resin has the structure shown in general formula II: Where n≥1; The R group contains a methyl group, or contains 1 to 30 -CH2 groups, or the R group is an aromatic group or its derivative, or the R group has a polyacrylate structure. The terminal group of the R group contains a reactive functional group, wherein the reactive functional group is any one of hydroxyl, carboxyl, epoxy, amino or C=C; X is one of O, NH or S; a, b, and c are constants ranging from 1 to 30; R1 is -OR', -NR'2 or -SR', or R1 is an alkyl, hydroxyalkyl or alkyl chain with 1 to 15 carbon atoms, or R1 is an olefinic group with 2 to 15 carbon atoms containing a double bond; R' is selected from any of the following structures and their derivative structures: Where m ≥ 1; R4 is hydrogen or methyl; Both R1 and R2 have at least one reactive functional group II at their end groups, wherein the reactive functional group II is any one of hydroxyl, carboxyl, epoxy, amino or C=C. R2 is a carboxyl group or its derivative, or an alkyl group, hydroxyalkyl group, alkyl chain with an epoxy group or aromatic derivative having 1 to 15 carbon atoms, or any one of hydrogen or heterocyclic group; R3 is any one or two of the following groups: phenyl or its derivative, pyridyl or its derivative, cyclohexyl or its derivative, pyrazolyl or its derivative, imidazole or its derivative, triazine or its derivative, triazolyl or its derivative, hydrogen, methyl, carboxyl or dioxane.

2. The negative photoresist based on POSS hyperbranched acrylate resin according to claim 1, characterized in that, The raw materials used to synthesize the POSS hyperbranched acrylate resin are polyfunctional oligomeric silsesquioxanes, (meth)acrylate monomers, and monomers containing R3 groups with ethylene unsaturated bonds.

3. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 2, characterized in that, The structure of the multifunctional oligomeric silsesquioxane is selected from the following general formula I: Among them, the R0 group contains a methyl group, or contains 1 to 20 -CH2 groups, or the R0 group is an aromatic group or its derivative, or the R0 group is one or more of polyether, polyamide, and polyamide-amine; The terminal group of R0 contains at least three reactive functional groups, wherein the reactive functional group is any one of hydroxyl, carboxyl, epoxy, amino, ester, aldehyde, carbonyl, alkenyl, aromatic unsaturated group or its derivative. n≥1。 4. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 2, characterized in that, The (meth)acrylate monomers are any one or more of the following: 2-hydroxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, diethylene glycol monoethyl ether (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol (meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentadienol (meth)acrylate, pentyltetraacrylate, ethyl 2-(acryloyloxy)benzoate, ethyl 2-(methacryloyloxy)benzoate, α,β-unsaturated (meth)carboxylic acid esters, and β-hydroxyethyl (meth)acrylate.

5. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 2, characterized in that, The monomer containing the R3 group and having an ethylene unsaturated bond is one or more of (meth)acrylates or their derivatives, maleic acid or its derivatives, norbornene and its derivatives, styrene, styrene and its derivatives, and styrene-cinnamic acid derivatives.

6. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 2, characterized in that, The initiator used to synthesize the POSS hyperbranched acrylate resin is an azo photoinitiator or an acetophenone compound, wherein the acetophenone compound is an α-amino ketone compound or an α-hydroxy ketone compound.

7. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 2, characterized in that, The chain transfer agent used to synthesize the POSS hyperbranched acrylate resin is a thiol compound, which is an aromatic thiol compound or an aliphatic monothiol compound.

8. The negative photoresist based on a POSS hyperbranched acrylate resin according to any one of claims 1-7, characterized in that, By weight, it comprises 50-100 parts of acrylate resin based on POSS hyperbranched structure, 0.01-20 parts of free radical polymerization initiator, 10-50 parts of unsaturated compound containing olefin bonds, 0.01-5 parts of surfactant, 0.01-5 parts of tackifier and 100-2000 parts of solvent.

9. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 8, characterized in that, The free radical polymerization initiator includes any one or a combination of two or more of acyl oxime compounds, acetophenone compounds, and biimidazole compounds.

10. The negative photoresist based on a POSS hyperbranched acrylate resin according to claim 8, characterized in that, The unsaturated compound containing an olefin bond is any one or a combination of two or more acrylates having difunctional or polyfunctional groups.

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