Photosensitive resist composition, photosensitive dry film and application

Abstract

The invention provides a photosensitive resist composition, a photosensitive dry film and application. The photosensitive resist composition is prepared from the following components in parts by weight: 20 to 45 parts of acrylic copolymer resin, 13 to 27 parts of a photopolymerizable compound and 0.3 to 2.3 parts of a first photoinitiator, a coating layer formed by curing the photosensitive resist composition is subjected to exposure treatment, and the ratio of the light inlet side double bond conversion rate to the light outlet side double bond conversion rate is 1.25-3.5; the weight-average molecular weight of the acrylic copolymer resin is less than or equal to 50,000. According to the invention, a specific proportioning system of the acrylic copolymer resin, the photopolymerizable compound and the first photoinitiator containing the thioxanthone and / or the benzophenone derivative is adopted, and the double bond conversion rate ratio of the light inlet side to the light outlet side under the condition of controlling the coating thickness is controlled; the purpose of forming a regular trapezoidal resist pattern with a narrow upper part, a wide lower part and a controllable section gradient after exposure and development is achieved.

Description

Technical Field

[0001] This invention relates to the field of photoresist, and more specifically, to a photoresist composition, a photosensitive dry film, and its applications. Background Technology

[0002] In the field of photovoltaic cell manufacturing, the metallization process is a key factor determining the photoelectric conversion efficiency and cost of the cell. Currently, N-type cells such as heterojunction (HJT) mainstream cells use screen-printed conductive silver paste to form the grid electrodes. However, silver paste is expensive, accounting for more than 30% of the cell's non-silicon cost, which severely restricts the large-scale mass production of high-efficiency cells. To reduce material costs, the industry is actively promoting a metallization technology path that replaces silver paste with copper electroplating. The core of this approach is to selectively electroplat copper on a metal seed layer on the surface of a transparent conductive oxide (TCO) layer using a patterned mask, forming a low-resistance, high aspect ratio copper grid structure.

[0003] The copper electroplating process mainly includes: TCO layer deposition, PVD deposition of a metal seed layer (such as Ni / Cu), photosensitive resist coating, exposure and development to form a pattern mask, copper electroplating, tin plating, mask stripping, seed layer flash etching, and surface passivation. Among these steps, the photosensitive resist, as the key medium for patterning, directly affects the final geometric morphology of the copper grid lines. Ideally, the copper grid lines should have a "trapezoidal" cross-section—that is, the width at the top (near the cell surface) is smaller than the width at the bottom (near the seed layer), with the width difference controlled within the range of 1~3 μm. This morphology effectively reduces the area of ​​the copper grid lines blocking sunlight, while simultaneously improving the uniformity of current distribution during electroplating, thereby increasing the cell's short-circuit current and conversion efficiency.

[0004] However, existing photosensitive resist systems generally suffer from insufficient morphology control precision in practical applications. For example, while some patents optimize the structure of alkali-soluble resins and the ratio of UV absorbers to achieve approximately rectangular or slightly trapezoidal cross-sections, it is difficult to consistently obtain an ideal structure that is narrower at the top and wider at the bottom, with the width difference precisely controlled within the range of 1-3 μm. Most commercial systems result in rectangular or approximately inverted trapezoidal groove cross-sections after development, sometimes even exhibiting vertical or outward-expanding sidewalls. This leads to "inverted cone" or "wide neck" structures during copper electroplating, increasing the light-blocking area and easily causing problems such as decreased adhesion of the electroplated layer, uneven current density distribution, and inconsistent plating thickness.

[0005] Furthermore, existing photoresist systems generally suffer from poor control over light penetration depth and curing gradient during exposure. Due to insufficient absorption characteristics and reaction kinetics design of the photoinitiation system, the curing degree of the photoresist coating tends to be uniform in the thickness direction, making it impossible to form a low cross-linking density region near the substrate. When the developer is applied, the dissolution rate of the exposed area tends to be consistent at the top and bottom of the coating, making it difficult to achieve the differential "lateral etching" behavior of almost insoluble upper part and slight dissolution lower part. As a result, it is impossible to form a controllable positive trapezoidal profile. In some cases, during development, as the unexposed area is slowly exposed, the upper part of the exposed area begins to come into contact with the developer in the early stage of development, while the lower part only comes into contact with the developer in the later stage of development, resulting in an inverted trapezoidal profile due to the erosion of the exposed area by the developer.

[0006] Furthermore, current mainstream photoresist products generally suffer from a trade-off between photosensitivity and imaging resolution: high-sensitivity systems are prone to overexposure and blurred image edges; high-resolution systems require higher exposure energy, extending the process cycle, and are difficult to achieve stable positive trapezoidal control under standard exposure equipment (such as 405nm LED light sources). These problems directly lead to large fluctuations in the yield of copper electroplated gate lines and poor mass production stability, becoming the core bottleneck restricting copper electroplating technology from the laboratory to large-scale production lines.

[0007] In summary, existing photosensitive resist technology still has significant technical shortcomings in achieving stable, controllable, and high-precision trapezoidal cross-section patterning. There is an urgent need to develop a new system that can synergistically regulate the photocuring gradient, development and dissolution rate, and imaging resolution to meet the stringent requirements of high-efficiency photovoltaic cells for the control of copper grid line morphology. Summary of the Invention

[0008] The main objective of this invention is to provide a photosensitive resist composition, a photosensitive dry film, and its application, in order to solve the problem that existing photosensitive resists cannot simultaneously satisfy both high imaging resolution and excellent imaging cross-sectional morphology.

[0009] To achieve the above objectives, a first aspect of the present invention provides a photosensitive resist composition, comprising, by weight, 20 to 45 parts of an acrylic copolymer resin, 13 to 27 parts of a photopolymerizable compound, and 0.3 to 2.3 parts of a first photoinitiator; the coating formed by curing the photosensitive resist composition, after exposure treatment, has a double bond conversion rate on the light-incoming side to a double bond conversion rate on the light-outgoing side of 1.25 to 3.5; the acrylic copolymer resin has a weight-average molecular weight ≤ 50,000; the first photoinitiator comprises at least one of a compound of formula I and a compound of formula II.

[0010]

[0011] Formula I

[0012]

[0013] Formula II

[0014] R1, R2, R3 and R4 are each independently hydrogen, C1-C12 alkyl, C1-C12 alkoxy, amide, benzamide, C1-C12 carboxylic acid ester or halogen; Ra, Rb, Rc and Rd are each independently C1-C12 alkyl.

[0015] Further, the first photoinitiator is 0.5 to 2.3 parts by weight; and / or, in Formula I, R1, R2, R3 and R4 are each independently hydrogen, C1 to C3 alkyl, C2 to C4 alkoxy, amide, benzamide or halogen; and / or, in Formula II, Ra, Rb, Rc and Rd are each independently C1 to C5 alkyl.

[0016] Further, in Formula I, R1, R2, R3, and R4 are each independently hydrogen, methyl, ethyl, n-propyl, isopropyl, ethoxy, propoxy, or chlorine; and / or, in Formula II, Ra, Rb, Rc, and Rd are each independently methyl, ethyl, n-propyl, or isopropyl; preferably, the compound of Formula I is selected from one or more of thioxanthone, 3-benzamidothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 4-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 1-chloro-4-propoxythioxanthone; and / or, the compound of Formula II is selected from one or more of 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(methyl, ethylamino)benzophenone, and 4,4'-bis(diethylamino)benzophenone.

[0017] Further, by weight, the photosensitive resist composition further includes 0.2 to 5 parts of a second photoinitiator; preferably, the second photoinitiator is selected from benzoin ether, anthraquinone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1 4-Naphthoquinone, 9,10-Phenanthroquinone, 2,3-Dimethylanthraquinone, 9-Phenylacetidine, 1,7-(9,9'-Acridinyl)heptane, Benzoin methyl ether, Benzoin ethyl ether, Benzoin phenyl ether, Benzoin dimethyl ketal, Benzoin dimethyl ether, Benzoin ethyl ether, Benzoin propyl ether, Benzoin phenyl ether, Tribromomethylphenyl sulfone, N-Phenylglycine, Benzophenone, 2-tert-butylanthraquinone, N,N - Dimethyl benzoate, dimethylamino ethyl benzoate, N,N-dimethylethanolamine, 2-(o-chlorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazolium dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2,2',4-tris(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4',5'-diphenyl-1,1'-diimidazole, 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, phenyl-3-(4-isopropylstyryl)-5-(4-isopropylphenyl)-pyrazoline, 9. One or more of the following: 10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-di(4-methoxyphenyl)-2-chloroanthracene, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime), and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]acetophenone 1-(O-acetyl oxime).

[0018] Further, by weight, the acrylic copolymer resin comprises 22 to 39.5 parts; and / or, the acrylic copolymer resin is obtained by copolymerization of at least one comonomer A containing a carboxyl group and at least one comonomer B without a carboxyl group; and / or, the weight-average molecular weight of the acrylic copolymer resin is 10,000 to 40,000; more preferably, comonomer A is selected from at least one of itaconic acid, crotonic acid, acrylic acid, methacrylic acid, maleic acid half ester, maleic acid, fumaric acid, vinylacetic acid, and vinylacetic anhydride; and / or, comonomer B is selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, isooctyl methacrylate, lauryl methacrylate, octadecyl methacrylate, and propyl methacrylate. At least one of the following: 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, methacrylonitrile, glycidyl methacrylate, ethyl N,N-dimethyl(meth)acrylate, ethyl N,N-diethyl(meth)acrylate, propyl N,N-dimethyl(meth)acrylate, propyl N,N-diethyl(meth)acrylate, butyl N,N-dimethyl(meth)acrylate, butyl N,N-diethyl(meth)acrylate, methacrylamide, N-hydroxymethylacrylamide, N-butoxymethylacrylamide, styrene, benzyl methacrylate, phenoxyethyl(meth)acrylate, nonylphenol(meth)acrylate, and alkoxylated nonylphenol(meth)acrylate.

[0019] Further, the photopolymerizable compound is a (meth)acrylate compound, and the molecular structure of the (meth)acrylate compound carries at least one vinyl group; preferably, the photopolymerizable compound is selected from lauryl methacrylate, isooctyl methacrylate, decyl methacrylate, phenoxyethyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, etc. Benzyl propoxylated bisphenol A di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polyethylene glycol propylene glycol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, glycerol tri(meth)acrylate, propoxylated glycerol tri(meth)acrylate, ethoxylated glycerol tri(meth)acrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, ethoxypropoxylated trimethylolpropane tri(meth)acrylate, quaternary Pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethoxylated pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, propoxylated pentaerythritol tri(meth)acrylate, propoxylated pentaerythritol tetra(meth)acrylate, ethoxypropoxylated pentaerythritol tri(meth)acrylate, ethoxypropoxylated pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, ethoxylated dipentaerythritol tri(meth)acrylate, propoxylated dipentaerythritol tri(meth)acrylate, ethoxylated propoxylated dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate The following are some of the following: acrylate, ethoxylated dipentaerythritol tetra(meth)acrylate, propoxylated dipentaerythritol tetra(meth)acrylate, ethoxylated propoxylated dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ethoxylated dipentaerythritol penta(meth)acrylate, propoxylated dipentaerythritol penta(meth)acrylate, ethoxylated propoxylated dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, propoxylated dipentaerythritol hexa(meth)acrylate, and ethoxylated propoxylated dipentaerythritol hexa(meth)acrylate.

[0020] Furthermore, the photosensitive resist composition also includes additives; the additives are selected from one or more of the following: thermal polymerization inhibitors, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial and antifungal agents, defoamers, leveling agents, fillers, thickeners, adhesion promoters, thixotropic promoters, colorants, photoinitiators, sensitizers, curing accelerators, anti-sticking agents, surface treatment agents, dispersants, surface modifiers, stabilizers, phosphors, rheology modifiers, and fillers; preferably, the additives include defoamers and leveling agents.

[0021] Furthermore, the photoresist composition further includes a solvent; the solvent is selected from one or more of alcohol solvents, ketone solvents, ether solvents, aromatic hydrocarbon solvents, and ester solvents; preferably, the alcohol solvent is selected from one or more of diethylene glycol, dipropylene glycol, butanol, and diacetone alcohol; and / or, the ketone solvent is selected from one or more of butanone, cyclohexanone, isophorone, diisobutyl ketone, and methyl butyl ketone; and / or, the ether solvent is selected from one or more of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, diethoxyethanol, dipropylene glycol methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol methyl ether; and / or, the aromatic hydrocarbon solvent is selected from one or more of toluene, xylene, and tetramethylbenzene; and / or, the ester solvent is selected from one or more of butyl acetate, butyl lactate, dipropylene glycol methyl ether acetate, and diethylene glycol ethyl ether acetate; more preferably, the solvent is dipropylene glycol methyl ether.

[0022] A second aspect of the present invention provides a dry film resist layer prepared from the above-described photoresist composition.

[0023] A third aspect of the present invention provides an application of the above-described dry film resist layer as a pattern transfer material in the fields of printed circuit boards, lead frames, solar cells, and conductor packaging.

[0024] By applying the technical solution of this invention, a specific ratio system of acrylic copolymer resin, photopolymerizable compound and first photoinitiator containing sulfur-containing xanthones and / or benzophenone derivatives is adopted. By controlling the double bond conversion ratio between the light-incoming side and the light-outgoing side under the coating thickness, optimizing the specific molecular weight range of the alkali-soluble film-forming main acrylic copolymer resin, limiting the molecular structure of the first photoinitiator, and ensuring the weight part range of each component, the purpose of forming a positive trapezoidal resist pattern with a narrow top and wide bottom and controllable cross-sectional gradient is achieved after exposure and development. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.

[0026] As described in the background section, existing photoresists suffer from the problem of simultaneously achieving high imaging resolution and excellent imaging cross-sectional morphology. To address this technical problem, a first aspect of the present invention provides a photoresist composition comprising, by weight, 20 to 45 parts of an acrylic copolymer resin, 13 to 27 parts of a photopolymerizable compound, and 0.3 to 2.3 parts of a first photoinitiator; the coating formed by curing the photoresist composition, after exposure treatment, has a double bond conversion rate on the light-incoming side to that on the light-outgoing side of 1.25 to 3.5; the acrylic copolymer resin has a weight-average molecular weight ≤ 50,000; and the first photoinitiator comprises at least one compound of formula I and formula II.

[0027]

[0028] Formula I

[0029]

[0030] Formula II

[0031] R1, R2, R3 and R4 are each independently hydrogen, C1-C12 alkyl, C1-C12 alkoxy, amide, benzamide, C1-C12 carboxylic acid ester or halogen; Ra, Rb, Rc and Rd are each independently C1-C12 alkyl.

[0032] In the composition provided by this invention, the photocuring gradient is synergistically optimized by controlling the molecular weight of acrylic acid, the type and proportion of photoinitiator, and the double bond conversion ratio on the light-incoming / light-outgoing side, thereby achieving good resolution and a positive trapezoidal morphology of the resulting resist layer. Specifically:

[0033] First, the type and proportion of the first photoinitiator must be precisely controlled and optimized. Compounds of Formula I and II have a large molar absorption coefficient at 355-405 nm, causing the intensity of light penetrating the coating to decrease rapidly along the thickness direction. This creates a light intensity gradient along the light propagation direction, meaning the light-incoming side has a higher light intensity and a higher double bond crosslinking density, while the light-outgoing side has a lower light intensity and a lower double bond crosslinking density. During development, the side with lower double bond crosslinking density dissolves more easily than the side with higher crosslinking density. If the first type of photoinitiator is less than 0.3 parts, the total amount of both types of photoinitiators is insufficient to form a sufficiently strong curing intensity gradient along the coating thickness direction. The curing intensity tends to be uniform along the thickness direction, making it difficult to create a sufficient "stronger at the top, weaker at the bottom" curing difference. Ultimately, due to the longer contact time between the top of the coating and the developer, an inverted trapezoidal morphology is formed. Conversely, if the amount is greater than 2.3 parts, the total concentration of photoinitiator is too high, creating an excessively strong curing intensity gradient along the coating thickness direction. This results in an excessively large width difference between the top and bottom of the trapezoidal morphology, leading to a deterioration in the cross-sectional morphology.

[0034] Secondly, the molecular weight of the acrylic copolymer resin is limited. For resist compositions, if the molecular weight of the main resin is >50,000, the chain segments are severely entangled, the viscosity is too high, and it is easy to clog the mesh during screen printing or for the battery cells to stick to the stencil, resulting in uneven coating thickness; moreover, the high molecular weight chain segments dissolve slowly, leading to poor resolution. Therefore, in order to improve resolution, the weight average molecular weight of the acrylic copolymer resin should be controlled to ≤50,000.

[0035] Based on the above, after the obtained composition is cured, the ratio of the double bond conversion rate on the light-incoming side to the double bond conversion rate on the light-outgoing side is strictly controlled to be 1.25~3.5. Preferably, the ratio of the double bond conversion rate on the light-incoming side to the double bond conversion rate on the light-outgoing side is 1.5~3.5.

[0036] To avoid ambiguity, in this invention, the above-mentioned ratio of light-incoming side double bond conversion rate to light-outgoing side double bond conversion rate means: the provided photoresist composition is coated and cured into a 13 μm thick coating, exposed with 16th energy level (41st exposure scale), and then FT-IR is applied at 810 cm⁻¹. -1 The ratio of the double bond conversion rates on the light-incoming side and the light-outcoming side of the coating is 1.25 to 3.5, preferably 1.5 to 3.5. The double bond conversion rate ratio is calculated using the following formula:

[0037]

[0038] Where A 2t A 20 The double bond is located at 810 cm⁻¹. -1 Area of ​​absorption peaks near the point of exposure before and after exposure; A 1t A 10 The C=O bond is located at 1730 cm. -1 The absorption peak areas before and after exposure are calculated. From this, the ratio of double bond conversion rate on the light-incoming side to that on the light-outgoing side can be calculated.

[0039] Regarding this ratio, if it is <1.25, it indicates that the curing degree on the light-emitting side is close to that on the light-incoming side, meaning that the light still has a relatively high intensity in the deep layers of the coating, leading to uniform curing. In this case, during development, the dissolution rates of the upper and lower layers in the unexposed area are similar, and the groove cross-section forms an inverted trapezoidal shape because the top of the coating takes longer to develop than the bottom, failing to achieve a "narrower at the top and wider at the bottom" shape. If it is >3.5, it indicates that the light-incoming side is fully cured, but the light has not effectively penetrated to the bottom of the coating, and the light-emitting side is almost uncured. In this case, the dissolution rate of the uncured area at the bottom by the developer is much higher than that at the top (because the top has already cross-linked into a network), causing the bottom of the groove to be excessively "hollowed out," forming a super-positive trapezoidal shape that is wider at the bottom and narrower at the top, or even resulting in drooping or collapse, failing to meet the requirements for copper layer morphology control during electroplating. A ratio range of 1.5 to 3.5 represents the optimal window for the synergistic or independent action of the two photoinitiators, resulting in a more ideal positive trapezoidal morphology (ideally a width difference of 1~3 μm). At this point, along the thickness direction of the resist layer, the closer to the bottom of the resist (such as the seed layer side of the solar cell), the lower the degree of curing, thus forming a curing gradient. The lower the degree of curing, the easier it is to develop and dissolve during development. After development, the grooves formed by the resist layer (unexposed parts) are more likely to exhibit a trapezoidal cross-sectional shape where the width of the upper side (light incident side) is smaller than the width of the lower side (light emitting side). In practical applications, such as after copper electroplating, it is possible to ultimately form grid lines with a good morphology and a trapezoidal cross-section.

[0040] In summary, this invention employs a first photoinitiator containing a derivative of formula I thioxanthone and / or formula II benzophenone, and limits its dosage. Simultaneously, by controlling the molecular weight of the acrylic copolymer and combining this with the control of the double bond conversion ratio between the light-incoming and light-outgoing sides, it achieves the goal of forming a trapezoidal resist groove with a controllable width difference and high resolution after development. This provides a high-precision, suitable sidewall tilt angle, and high-resolution pattern mask for copper electroplating processes.

[0041] For the first photoinitiator, to further enhance photolysis efficiency, it is preferable that: in Formula I, R1, R2, R3, and R4 are each independently hydrogen, a C1-C3 alkyl group, a C2-C4 alkoxy group, an amide group, a benzamide group, or a halogen; and / or, in Formula II, Ra, Rb, Rc, and Rd are each independently C1-C5 alkyl groups. Furthermore, to promote more stable photosensitivity in the resulting composition, thereby obtaining better development results, it is further preferable that: in Formula I, R1, R2, R3, and R4 are each independently hydrogen, methyl, ethyl, n-propyl, isopropyl, ethoxy, propoxy, or chlorine; and / or, in Formula II, Ra, Rb, Rc, and Rd are each independently methyl, ethyl, n-propyl, or isopropyl. And, in several preferred embodiments, the first photoinitiator is present in a weight ratio of 0.5 to 2.3 parts to further optimize the curing strength gradient and form a better cross-sectional morphology after curing.

[0042] In practical applications, the compound of Formula I is selected from one or more of thioxanthone, 3-benzamidothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 4-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 1-chloro-4-propoxythioxanthone; and / or, the compound of Formula II is selected from one or more of 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(methyl, ethylamino)benzophenone, and 4,4'-bis(diethylamino)benzophenone. Specifically, for 4,4'-bis(methyl, ethylamino)benzophenone, in Formula II, Ra = Rb = methyl; Rc = Rd = ethyl.

[0043] Based on the aforementioned first photoinitiator, the photosensitive resist composition further comprises 0.2 to 5 parts by weight of a second photoinitiator, preferably 0.2 to 4.2 parts. Since the first photoinitiator dominates the curing gradient, the second photoinitiator preferably used in this invention does not primarily participate in the control of the main gradient, but mainly serves to improve overall photosensitivity. In the composition, the second photoinitiator has virtually no effect on the depth gradient. Therefore, without affecting the positive trapezoidal morphology, the energy required to expose to the 16th exposure level is reduced, thereby improving production line efficiency and resolution. Specifically, the second photoinitiator can be selected from benzoin ether, anthraquinone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1... 4-Naphthoquinone, 9,10-Phenanthroquinone, 2,3-Dimethylanthraquinone, 9-Phenylacetidine, 1,7-(9,9'-Acridinyl)heptane, Benzoin methyl ether, Benzoin ethyl ether, Benzoin phenyl ether, Benzoin dimethyl ketal, Benzoin dimethyl ether, Benzoin ethyl ether, Benzoin propyl ether, Benzoin phenyl ether, Tribromomethylphenyl sulfone, N-Phenylglycine, Benzophenone, 2-tert-butylanthraquinone, N,N - Dimethyl benzoate, dimethylamino ethyl benzoate, N,N-dimethylethanolamine, 2-(o-chlorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazolium dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2,2',4-tris(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4',5'-diphenyl-1,1'-diimidazole, 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, phenyl-3-(4-isopropylstyryl)-5-(4-isopropylphenyl)-pyrazoline, 9. One or more of the following: 10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-di(4-methoxyphenyl)-2-chloroanthracene, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime), and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]acetophenone 1-(O-acetyl oxime).

[0044] Furthermore, the preferred weight percentage of the acrylic copolymer resin is 22-39.5 parts to more effectively balance photosensitivity, resolution, and film-forming properties. Insufficient dosage results in poor film-forming properties; excessive dosage may reduce photosensitivity and resolution. Meanwhile, for the acrylic copolymer resin, a weight-average molecular weight of 10,000-40,000 is preferred. At this weight, the chain length of the acrylic copolymer resin is more suitable, ensuring both film formation and the resistance of the cured resist layer to developer erosion, while also providing sufficient resolution for better development results.

[0045] Furthermore, the acrylic copolymer resin used in this invention is obtained by copolymerizing at least one comonomer A containing a carboxyl group and at least one comonomer B without a carboxyl group. In practical applications, comonomer A is selected from at least one of itaconic acid, crotonic acid, acrylic acid, methacrylic acid, maleic acid half ester, maleic acid, fumaric acid, vinylacetic acid, and vinylacetic anhydride; and / or, comonomer B is selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, isooctyl methacrylate, lauryl methacrylate, octadecyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, and polyethylene glycol mono(meth)acrylate. The following are at least one of the following: polypropylene glycol mono(meth)acrylate, (meth)acrylonitrile, (meth)acrylate glycidyl acrylate, N,N-dimethyl(meth)acrylate ethyl acrylate, N,N-diethyl(meth)acrylate ethyl acrylate, N,N-dimethyl(meth)acrylate propyl acrylate, N,N-diethyl(meth)acrylate propyl acrylate, N,N-dimethyl(meth)acrylate butyl acrylate, N,N-diethyl(meth)acrylate butyl acrylate, (meth)acrylamide, N-hydroxymethylacrylamide, N-butoxymethylacrylamide, styrene, (meth)acrylate benzyl acrylate, phenoxyethyl(meth)acrylate, nonylphenol (meth)acrylate, and alkoxylated nonylphenol (meth)acrylate.

[0046] To better synergize with the two photoinitiators mentioned above and further optimize the curing depth, thereby obtaining better development results, it is preferable that the photopolymerizable compound is a (meth)acrylate compound, and the molecular structure of the (meth)acrylate compound carries at least one vinyl group. In practical applications, the photopolymerizable compound can be selected from lauryl methacrylate, isooctyl methacrylate, decyl methacrylate, phenoxyethyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, ethoxylated propoxylated bisphenol A di(meth)acrylate, polyethylene glycol di(meth)acrylate, and polypropylene glycol di(meth)acrylate. (Meth)acrylate, polyethylene glycol propylene glycol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, glycerol tri(meth)acrylate, propoxylated glycerol tri(meth)acrylate, ethoxylated glycerol tri(meth)acrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, ethoxypropoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate Ester, ethoxylated pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, propoxylated pentaerythritol tri(meth)acrylate, propoxylated pentaerythritol tetra(meth)acrylate, ethoxypropoxylated pentaerythritol tri(meth)acrylate, ethoxypropoxylated pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, ethoxylated dipentaerythritol tri(meth)acrylate, propoxylated dipentaerythritol tri(meth)acrylate, ethoxylated propoxylated dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, ethoxylated dipentaerythritol tri(meth)acrylate One or more of the following: pentaerythritol tetra(meth)acrylate, propoxylated dipentaerythritol tetra(meth)acrylate, ethoxylated propoxylated dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ethoxylated dipentaerythritol penta(meth)acrylate, propoxylated dipentaerythritol penta(meth)acrylate, ethoxylated propoxylated dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, propoxylated dipentaerythritol hexa(meth)acrylate, and ethoxylated propoxylated dipentaerythritol hexa(meth)acrylate.

[0047] Furthermore, in practical applications, the preferred photoresist composition also includes additives (specifically 0.1 to 1 part) to significantly improve the stability, adhesion to the substrate, and coating processability of the resulting photoresist composition. Specific additives can be selected from one or more of the following: thermal polymerization inhibitors, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial and antifungal agents, defoamers, leveling agents, fillers, thickeners, adhesion promoters, thixotropic promoters, colorants, photoinitiators, sensitizers, curing accelerators, anti-sticking agents, surface treatment agents, dispersants, surface modifiers, stabilizers, phosphors, rheology modifiers, and fillers. Regarding the additives, to further reduce residual bubbles during screen printing and improve coating smoothness, it is preferable that they include defoamers and leveling agents.

[0048] Furthermore, the preferred photoresist composition also includes a solvent (specifically, 40% to 60% of the total weight of the composition) to better balance volatility, solubility, and viscosity, thereby achieving better coating processability. The solvent may be selected from one or more of alcohol solvents, ketone solvents, ether solvents, aromatic hydrocarbon solvents, and ester solvents. Wherein: alcohol solvents are selected from one or more of diethylene glycol, dipropylene glycol, butanol, and diacetone alcohol; and / or ketone solvents are selected from one or more of butanone, cyclohexanone, isophorone, diisobutyl ketone, and methyl butyl ketone; and / or ether solvents are selected from one or more of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, diethoxyethanol, dipropylene glycol methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol methyl ether; and / or aromatic hydrocarbon solvents are selected from one or more of toluene, xylene, and tetramethylbenzene; and / or ester solvents are selected from one or more of butyl acetate, butyl lactate, dipropylene glycol methyl ether acetate, and diethylene glycol ethyl ether acetate. In this invention, dipropylene glycol methyl ether is preferred as the solvent, as it has more suitable volatility, solubility, and economy.

[0049] The specific preparation method of the above-mentioned photosensitive resist composition can be obtained by various known processes, and the conditions and parameters involved are all commonly known to those skilled in the art, and are not limited in this invention.

[0050] A second aspect of the present invention provides a dry film resist layer prepared from the above-described photoresist composition.

[0051] A third aspect of the present invention provides an application of the above-described dry film resist layer as a pattern transfer material in the fields of printed circuit boards, lead frames, solar cells, and conductor packaging.

[0052] In particular, exemplarily speaking, when used in the preparation of metal grid lines in photovoltaic cells, the preparation process involves: screen printing the aforementioned photoresist composition onto the seed conductor layer of the photovoltaic cell, followed by drying to obtain a dry film photoresist layer; then selectively transmitting active light through the dry film photoresist layer to form an exposure step for photocuring; removing the dry film photoresist layer outside the photocuring area to form a photoresist pattern on the photovoltaic cell; then depositing the photovoltaic cell with the photoresist pattern to form a metal grid line pattern; and finally stripping the photovoltaic cell with the metal grid line pattern to obtain the metal grid lines. The resulting metal grid lines have a trapezoidal cross-sectional pattern and exhibit excellent pattern performance with high resolution.

[0053] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0054] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0055] Synthesis example

[0056] Synthesis of A-1 acrylic copolymer resin:

[0057] 10 parts by weight of acrylic acid, 5 parts by weight of phenoxyethyl acrylate, 70 parts by weight of methyl methacrylate, and 15 parts by weight of ethyl acrylate were mixed thoroughly. 3 parts by weight of initiator AIBN were added and stirred until dissolved. 70 parts by weight of dipropylene glycol methyl ether was added to a three-necked flask equipped with a reflux condenser and nitrogen protection. The mixture was heated to 110°C, and the above mixture was added dropwise over 3 hours with stirring. The reaction was continued at this temperature for 4 hours. Then, 0.2 parts by weight of dipropylene glycol methyl ether solution containing the initiator was added in two separate additions, 1 hour apart. After each addition, the mixture was stirred at this temperature for 3 hours to stop the reaction, yielding alkali-soluble resin A-1 with a weight-average molecular weight of 39,200 and a solid content of 50%.

[0058] A-2 to A-6 were prepared using the above synthesis method.

[0059] The component information involved in the various embodiments and comparative examples provided in this application is as follows:

[0060] A-1: Acrylic acid-phenoxyethyl acrylate-methyl methacrylate-ethyl acrylate = 10-5-70-15, weight average molecular weight: 39,200, solid content: 50%.

[0061] A-2: Acrylic acid-styrene-benzyl methacrylate-methyl methacrylate = 25-50-20-5, weight average molecular weight: 11,000, solid content: 50%.

[0062] A-3: Acrylic acid-benzyl methacrylate-methyl methacrylate-butyl acrylate = 14-15-60-11, weight average molecular weight: 31,500, solid content: 50%.

[0063] A-4: Methacrylate-styrene-methyl methacrylate-ethyl acrylate = 19-35-36-10, weight average molecular weight: 23,300, solid content: 50%.

[0064] A-5: Methacrylate-styrene-methyl methacrylate-ethyl acrylate = 19-35-36-10, weight average molecular weight: 72,000, solid content: 50%.

[0065] A-6: Methacrylate-styrene-methyl methacrylate-ethyl acrylate = 19-35-36-10, weight average molecular weight: 45,000, solid content: 50%.

[0066] B-1: Trimethylolpropane triacrylate, Sartoma SR351.

[0067] B-2: Dipentaerythritol hexaacrylate, Miramer M600.

[0068] C-1: Tribromomethylphenyl sulfone, Aladdin reagent.

[0069] C-2: 9-Phenylacetidine, Changzhou Qiangli New Materials.

[0070] C-3: 2-(o-chlorophenyl)-4,5-diphenylimidazolium dimer, Changzhou Qiangli New Materials.

[0071] C-4: N-phenylglycine, Aladdin reagent.

[0072] C-5: Dibutoxyanthracene, Changzhou Qiangli New Materials.

[0073] C-6: 2-Chlorothionone, Aladdin reagent.

[0074] C-7: 1-Chloro-4-propoxythionone, Aladdin reagent.

[0075] C-8: 2,4-Diethylthioxanthone, Aladdin reagent.

[0076] C-9: 2-Isopropylthioxanthraquinone, Aladdin reagent.

[0077] C-10: Tetraethylmirlidone, Changzhou Qiangli New Materials.

[0078] C-11: 4,4'-bis(methyl, ethylamino)benzophenone, Aladdin reagent.

[0079] C-12: 4,4'-bis(dimethylamino)benzophenone, Aladdin reagent.

[0080] D-1: Defoamer KS-66, Shin-Etsu Chemical, Japan.

[0081] D-2: Leveling agent FLOW300 (Digo).

[0082] E-1: Dipropylene glycol methyl ether.

[0083] Among them, C-6, C-7, C-8, and C-9 are thioxanthone compounds that satisfy formula I; C-10, C-11, and C-12 are benzophenone compounds that satisfy formula II.

[0084] The specific selection and relative weight of each component in the various embodiments and comparative examples of this invention are detailed in Tables 1-1 to 1-4 (the acrylic copolymer resin in the tables has been converted to dry weight, and the solvents contained in A1-A6 have been converted to E-1). In the process of preparing the composition, insoluble additives, solvents, etc., are added to a sealed container and dispersed using a sand mill disperser. Then, photoinitiators, other auxiliaries, and photopolymerizable compounds are added and dispersed again using a sand mill disperser. Finally, the acrylic copolymer resin is added and dispersed uniformly using a sand mill disperser.

[0085] Table 1-1

[0086]

[0087] Table 1-2

[0088]

[0089] Table 1-3

[0090]

[0091] Table 1-4

[0092]

[0093] Performance evaluation methods:

[0094] The photosensitive resist compositions obtained in each embodiment and comparative example were screen printed on a battery cell with a seed layer deposited using a screen printing process. A suitable mesh size (exemplarily 150 mesh) was selected. The photosensitive resist ink was then screen printed on the cell and baked in an oven at 95°C for 5-10 minutes to obtain a coating with a thickness of 13 micrometers. The performance was then evaluated.

[0095] Developing conditions: The developer is a 1% sodium carbonate aqueous solution; the developing temperature is 30℃; and the spray pressure is 1.5 kg / cm². 2 .

[0096] Minimum development time determination: Under the above development conditions, the minimum time required to completely dissolve and remove the unexposed resist layer is taken as the minimum development time.

[0097] Energy determination for the 16th exposure: Exposure was performed using an Adtec IP-6 (405nm) exposure unit, and the exposure energy was measured using a Stouffer 41-division exposure scale. The energy range was 20–200 mJ / cm². 2 The photosensitive resin composition layer was exposed using energy (exposure) across an exposure scale of 41 steps. After exposure, development was performed using twice the minimum development time to remove unexposed areas. This resulted in a cured film formed from the cured photosensitive resin layer on the copper surface of the substrate. The energy required to achieve a residual exposure scale of 16 steps (unit: mJ / cm²) for the cured film was determined. 2 ).

[0098] Determination of the double bond conversion ratio on the light-incoming side to the double bond conversion ratio on the light-outgoing side: A resist ink composition was coated onto a 15-micron transparent PET substrate and baked in a 95°C oven for 5-10 minutes to obtain a 13-micron thick coating. The same PET layer was then laminated on the other side. Exposure was performed using the required energy level (41 exposure scale), and the light-incoming and light-outgoing sides were marked. The substrate was left to stand for 15 minutes. The PET layers on both sides were then removed, and the FT-IR spectra on the light-incoming and light-outgoing sides were measured using an infrared spectrometer (Nicolet IS20) at 1730 cm⁻¹. -1 Make reference adjustments on both sides, at 810cm -1 The double bond conversion rates on the light-incoming and light-outcoming sides of the resist composition coating are characterized. The double bond conversion is calculated using the following formula.

[0099]

[0100] Where A 2t A 20 The double bond is located at 810 cm⁻¹. -1 Area of ​​absorption peaks near the point of exposure before and after exposure; A 1t A 10 The C=O bond is located at 1730 cm. -1 The absorption peak areas before and after exposure are calculated. From this, the ratio of double bond conversion rate on the light-incoming side to that on the light-outgoing side can be calculated.

[0101] Evaluation of resist resolution: Using a wiring pattern with a width of 400:X (X=5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 24, 26, 28, 30) of exposed and unexposed portions, expose it with the energy corresponding to the 16th order (41st order exposure scale), let it stand for 15 minutes, develop it with 2.5 times the minimum development time, and observe it with a microscope with a magnification of 50x. The width of the minimum mask gap (the groove formed by removing the unexposed resist) that normally forms is taken as the resolution value. The lower this value, the better the resolution.

[0102] Evaluation of the resist cross-sectional morphology: In the resolution evaluation mentioned above, the resist pattern formed includes a portion with a 15μm wide mask gap (groove). The silicon wafer is broken along a direction perpendicular to the groove, and the shape of the groove formed by the resist is observed to evaluate the resist cross-sectional shape. If the resist groove is a cross-section that is narrower at the top and wider at the bottom (i.e., the width of the top edge is 1-3 μm less than the width of the bottom edge), it is rated "A"; if it is, ... The best shape is a narrow top and wide bottom with a width difference of 1 to 3 micrometers (A); a narrow top and wide bottom with a width difference of 0 to 1 micrometer (B) is acceptable, but not the best; the worst shape is an inverted trapezoid with a wide top and narrow bottom (D).

[0103] Based on the above testing and evaluation methods, the evaluation results of the double bond conversion rate on the light-incoming side / double bond conversion rate on the light-outgoing side, the resist resolution, and the resist cross-sectional morphology for each embodiment and comparative example are shown in Table 2.

[0104] Table 2

[0105]

[0106] As can be seen from the above description, the above embodiments of the present invention achieve the preparation of a high-performance photoresist composition, and the obtained photoresist composition can form a positive trapezoidal photoresist pattern with a narrow top and wide bottom and a controllable cross-sectional gradient after exposure and development.

[0107] Specifically, in each comparative example: Comparative Example 1 had an excessively high double bond conversion ratio between the light-incoming and light-outgoing sides, resulting in a large difference in size between the lower edge and the upper edge of the trapezoidal groove formed by the resist, leading to poor morphology; Comparative Example 2 did not use compounds with structural formulas (I) and / or (II), and the double bond conversion ratio between the light-incoming and light-outgoing sides was lower than the lower limit of this application, resulting in a poor morphology in the groove cross-section formed by the resist, where the difference in width between the lower edge and the upper edge of the trapezoid was insufficient and negative (the upper edge width was larger than the lower edge width, and the shape was an inverted trapezoid); Comparative Example 3 used a resin with a larger molecular weight (A-5), which resulted in a decrease in the resolution of the resist.

[0108] In the various embodiments:

[0109] Comparing Examples 1 to 9 with Examples 1 to 9, it can be seen that by gradually optimizing the amount of the second photoinitiator, the overall photosensitivity can be improved more effectively, thereby reducing the energy required for exposure to the 16th level without affecting the positive trapezoidal morphology, and thus improving production line efficiency and resolution.

[0110] Comparing Example 15 with Examples 1 to 9, it can be seen that by optimizing the weight-average molecular weight of the acrylic copolymer resin, its chain length can be made more suitable, thereby ensuring both film formation and the resistance of the cured resist layer to developer erosion, while also providing sufficient resolution and achieving better development results.

[0111] Comparing Examples 16 and 17 with Examples 1 to 9, it can be seen that by optimizing the weight parts of each component, it is possible to more effectively combine photosensitivity, high resolution, and better cross-sectional morphology.

[0112] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.

[0113] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A photosensitive resist composition, characterized in that, The photosensitive resist composition comprises, by weight, 20 to 45 parts of acrylic copolymer resin, 13 to 27 parts of photopolymerizable compound, and 0.3 to 2.3 parts of first photoinitiator; The coating formed by curing the photosensitive resist composition and then exposing it has a double bond conversion rate on the light-incoming side to a double bond conversion rate on the light-outgoing side of 1.25 to 3.

5. The weight-average molecular weight of the acrylic copolymer resin is ≤50,000; The first photoinitiator includes at least one of the compounds of formula I and formula II: Formula I Formula II R1, R2, R3 and R4 are each independently hydrogen, C1-C12 alkyl, C1-C12 alkoxy, amide, benzamide, C1-C12 carboxylic acid ester or halogen; Ra, Rb, Rc and Rd are each independently C1-C12 alkyl.

2. The photosensitive resist composition according to claim 1, characterized in that, The first photoinitiator has a weight ratio of 0.5 parts to 2.3 parts; and / or, In Formula I, R1, R2, R3, and R4 are each independently hydrogen, a C1-C3 alkyl group, a C2-C4 alkoxy group, an amide group, a benzamide group, or a halogen; and / or, In Formula II, Ra, Rb, Rc and Rd are each independently a C1 to C5 alkyl group.

3. The photosensitive resist composition according to claim 1 or 2, characterized in that, In Formula I, R1, R2, R3, and R4 are each independently hydrogen, methyl, ethyl, n-propyl, isopropyl, ethoxy, propoxy, or chlorine; and / or, In Formula II, Ra, Rb, Rc and Rd are each independently methyl, ethyl, n-propyl or isopropyl; Preferably, the compound of Formula I is selected from one or more of thioxanthone, 3-benzamidothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 4-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 1-chloro-4-propoxythioxanthone; and / or, the compound of Formula II is selected from one or more of 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(methyl, ethylamino)benzophenone, and 4,4'-bis(diethylamino)benzophenone.

4. The photoresist composition according to any one of claims 1 to 3, characterized in that, The photoresist composition further comprises 0.2 to 5 parts by weight of a second photoinitiator; Preferably, the second photoinitiator is selected from benzoin ether, anthraquinone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2,3-dimethylanthraquinone, 9-phenylacridinium, 1,7-(9,9'-acridyl)heptane, benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, benzoin dimethyl ketal, benzoin dimethyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin phenyl ether, tribromomethylphenyl sulfone, N-phenylglycine, benzophenone, 2-tert-butylanthraquinone, N,N - Dimethyl benzoate, dimethylamino ethyl benzoate, N,N-dimethylethanolamine, 2-(o-chlorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazolium dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazolium dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazolium dimer, 2,2',4-tris(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4',5'-diphenyl-1,1'-diimidazole, 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, phenyl-3-(4-isopropylstyryl)-5-(4-isopropylphenyl)-pyrazoline, 9. One or more of the following: 10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-di(4-methoxyphenyl)-2-chloroanthracene, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime), and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]acetophenone 1-(O-acetyl oxime).

5. The photoresist composition according to any one of claims 1 to 4, characterized in that, The acrylic copolymer resin has a weight ratio of 22-39.5 parts; and / or, The acrylic copolymer resin is obtained by copolymerization of at least one comonomer A containing a carboxyl group and at least one comonomer B without a carboxyl group; and / or, The weight-average molecular weight of the acrylic copolymer resin is 10,000 to 40,000. More preferably, the comonomer A is selected from at least one of itaconic acid, crotonic acid, acrylic acid, methacrylic acid, maleic acid half ester, maleic acid, fumaric acid, vinylacetic acid, and vinylacetic anhydride; and / or, the comonomer B is selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, isooctyl methacrylate, lauryl methacrylate, octadecyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, and polyethylene glycol mono(meth)acrylate. The following are included: esters, polypropylene glycol mono(meth)acrylate, (meth)acrylonitrile, glycidyl (meth)acrylate, ethyl N,N-dimethyl (meth)acrylate, ethyl N,N-diethyl (meth)acrylate, propyl N,N-dimethyl (meth)acrylate, propyl N,N-diethyl (meth)acrylate, butyl N,N-diethyl (meth)acrylate, butyl N,N-diethyl (meth)acrylate, (meth)acrylamide, N-hydroxymethyl-acrylamide, N-butoxymethyl-acrylamide, styrene, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenol (meth)acrylate, and alkoxylated nonylphenol (meth)acrylate.

6. The photoresist composition according to any one of claims 1 to 5, characterized in that, The photopolymerizable compound is a (meth)acrylate compound, and the molecular structure of the (meth)acrylate compound carries at least one vinyl group; Preferably, the photopolymerizable compound is selected from lauryl methacrylate, isooctyl methacrylate, decyl methacrylate, phenoxyethyl methacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, bisphenol A dimethacrylate, ethoxylated bisphenol A dimethacrylate, propoxylated bisphenol A dimethacrylate, ethoxylated propoxylated bisphenol A dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, etc. Methacrylates, polyethylene glycol propylene glycol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, glycerol tri(meth)acrylate, propoxylated glycerol tri(meth)acrylate, ethoxylated glycerol tri(meth)acrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, ethoxypropoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate Ethoxylated pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, propoxylated pentaerythritol tri(meth)acrylate, propoxylated pentaerythritol tetra(meth)acrylate, ethoxypropoxylated pentaerythritol tri(meth)acrylate, ethoxypropoxylated pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, ethoxylated dipentaerythritol tri(meth)acrylate, propoxylated dipentaerythritol tri(meth)acrylate, ethoxylated propoxylated dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, ethoxylated dipentaerythritol One or more of the following: tetrapentaerythritol tetra(meth)acrylate, propoxylated dipentaerythritol tetra(meth)acrylate, ethoxylated propoxylated dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ethoxylated dipentaerythritol penta(meth)acrylate, propoxylated dipentaerythritol penta(meth)acrylate, ethoxylated propoxylated dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, propoxylated dipentaerythritol hexa(meth)acrylate, and ethoxylated propoxylated dipentaerythritol hexa(meth)acrylate.

7. The photoresist composition according to any one of claims 1 to 6, characterized in that, The photosensitive resist composition further includes additives; the additives are selected from one or more of the following: thermal polymerization inhibitors, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial and antifungal agents, defoamers, leveling agents, fillers, thickeners, adhesion promoters, thixotropic promoters, colorants, photoinitiators, sensitizers, curing accelerators, anti-sticking agents, surface treatment agents, dispersants, surface modifiers, stabilizers, phosphors, rheology modifiers, and fillers; Preferably, the additives include defoamers and leveling agents.

8. The photoresist composition according to any one of claims 1 to 7, characterized in that, The photosensitive resist composition further includes a solvent; the solvent is selected from one or more of alcohol solvents, ketone solvents, ether solvents, aromatic hydrocarbon solvents, and ester solvents; Preferably, the alcohol solvent is selected from one or more of diethylene glycol, dipropylene glycol, butanol, and diacetone alcohol; and / or, the ketone solvent is selected from one or more of butanone, cyclohexanone, isophorone, diisobutyl ketone, and methyl butyl ketone; and / or, the ether solvent is selected from one or more of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, diethoxyethanol, dipropylene glycol methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol methyl ether; and / or, the aromatic hydrocarbon solvent is selected from one or more of toluene, xylene, and tetramethylbenzene; and / or, the ester solvent is selected from one or more of butyl acetate, butyl lactate, dipropylene glycol methyl ether acetate, and diethylene glycol ethyl ether acetate. More preferably, the solvent is dipropylene glycol methyl ether.

9. A dry film resist layer, characterized in that, The dry film resist layer is prepared from the photosensitive resist composition according to any one of claims 1 to 8.

10. The application of the dry film resist layer of claim 9 as a pattern transfer material in the fields of printed circuit boards, lead frames, solar cells, and conductor packaging.

Images