KR102609268B1 - Photoresist film and application thereof - Google Patents

Abstract

Photoresist films and applications thereof are provided. The photoresist film has a shear loss modulus G" at 30° C. and a shear storage modulus G' at 30° C., where the ratio of G" to G' (G"/G') ranges from 0.50 to 10.40.

Description

Photoresist film and its application {PHOTORESIST FILM AND APPLICATION THEREOF}

claim priority

This application claims the benefit of Taiwan Patent Application No. 111105671 filed on February 16, 2022, the subject matter of which is incorporated herein by reference in its entirety.

field of invention

This application provides photoresist films, particularly high-thickness photoresist films, and applications thereof.

Description of related technologies

Generally, a photoresist film consists of a resin, a photosensitive material, and additive(s), and may be a positive-type photoresist film or a negative-type photoresist film depending on the state of the photoresist film after exposure and development. In the case of positive photoresist films, the developer will dissolve the areas exposed to light, leaving behind areas that are not exposed to light. In the case of negative photoresist film, the developer will dissolve the parts that are not exposed to light, leaving behind the parts that are exposed to light.

In the printed circuit board (PCB) industry, photoresist films are used in etching processes to form circuit patterns. As the complexity and size of electronic components increases, the printed circuit board industry requires thick photoresist films with high depth-to-width ratios. However, the existing photoresist film had problems such as poor adhesion to the substrate, wrinkles, or resin leakage during the adhesion process, resulting in uneven thickness of the photoresist film and poor etching accuracy.

Summary of the Invention

In consideration of the above technical problems, the present application provides a high-thickness photoresist film with excellent workability, adhesive performance, and appearance.

Accordingly, the object of the present application is to have a shear loss modulus at 30° C. G" and a shear storage modulus at 30° C. G', wherein the ratio of G" to G' (G"/G' ) ranges from 0.50 to 10.40. In some embodiments of the present application, the ratio of G" to G' ranges from 0.50 to 10.36.

In some embodiments of the present application, the shear storage modulus G' at 30°C ranges from 0.001 kPa to 4300 kPa and the shear loss modulus G" at 30°C ranges from 0.08 kPa to 1900 kPa.

In some embodiments of the present application, the shear loss modulus G" at 30° C. and the shear storage modulus G' at 30° C. are measured using a rheometer under the following operating conditions: The fixture is 25 mm parallel. The plate is ETC aluminum, the mode is shear mode, the immersion time is 0 seconds, the initial temperature is 30 ℃, the ramp rate is 3 ℃/min, the final temperature is 150 ℃, the immersion time after ramp is 0 sec, pressure is 1000 Pa, the measurement is made at a single point, and the frequency is 1 Hz.

In some embodiments of the present application, the photoresist film has a thickness ranging from 60 μm to 600 μm, such as 65 μm to 400 μm.

In some embodiments of the present application, the photoresist film is a negative photoresist film.

In some embodiments of the present application, the negative photoresist film includes a carboxyl-containing (meth)acrylic based polymer and a photopolymerization initiator.

Another object of the present application is to provide a composite film comprising the above-mentioned photoresist film and a protective film formed on at least one surface of the photoresist film.

In some embodiments of the present application, the protective film is selected from the group consisting of polyethylene terephthalate films, polyolefin films, and composites thereof.

In order to make the above objects, technical features and advantages of the present application clearer, the present application will be described in detail below with reference to some specific embodiments.

Hereinafter, some specific embodiments of the present application will be described in detail. However, the present application may be implemented in various embodiments and is not limited to the embodiments described herein.

The expressions “a”, “the”, etc. cited in the specification (especially the claims that follow) include both singular and plural forms, unless otherwise specified.

The term “(meth)acrylic” mentioned herein is intended to include both “acrylic” and “methacrylic” unless otherwise specified. For example, the term “carboxyl-containing (meth)acrylic based polymer” is meant to encompass carboxyl-containing acrylic based polymers and carboxyl-containing methacrylic based polymers. The term “(meth)acrylate” referred to herein is intended to encompass acrylates and methacrylates. For example, the term “methyl (meth)acrylate” is intended to encompass methyl acrylate and methyl methacrylate.

Compared to the prior art, the effect of the present application is mainly to provide a thick photoresist film with excellent adhesion performance, appearance, and workability by controlling the rheological properties of the photoresist film. A detailed description of the photoresist film and its application is as follows.

1. Photoresist film

The photoresist film of the present application has specific rheological properties. In the present application, photoresist films can be prepared using suitable polymerizable compound(s). A detailed description of the rheological properties of the photoresist film and exemplary manufacturing methods is provided below.

1.1. Rheological properties of photoresist films

The photoresist films of the present application have a shear loss modulus G" at 30°C and a shear storage modulus G' at 30°C, where the ratio of G" to G' ranges from 0.50 to 10.40. For example, the ratio of G" to G' is 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.30, 1.35, 1. .40, 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, 1.90, 1.95, 2.00, 2.10, 2.15, 2.20, 2.25, 2.30, 2.35, 2.40, 2.45, 2 .50, 2.55, 2.60, 2.65, 2.70, 2.75, 2.80, 2.85, 2.90, 2.95, 3.00, 3.05, 3.10, 3.15, 3.20, 3.25, 3.30, 3.35, 3.40, 3.45, 3.50, 3.55, 3.60, 3.65, 3.70, 3 .75, 3.80, 3.85, 3.90, 3.95, 4.00, 4.05, 4.10, 4.15, 4.20, 4.25, 4.30, 4.35, 4.40, 4.45, 4.50, 4.55, 4.60, 4.65, 4.70, 4.75, 4.80, 4.85, 4.90, 4.95, 5 .00, 5.05, 5.10, 5.15, 5.20, 5.25, 5.30, 5.35, 5.40, 5.45, 5.50, 5.55, 5.60, 5.65, 5.70, 5.75, 5.80, 5.85, 5.90, 5.95, 6.00, 6.05, 6.10, 6.15, 6.20, 6 .25, 6.30, 6.35, 6.40, 6.45, 6.50, 6.55, 6.60, 6.65, 6.70, 6.75, 6.80, 6.85, 6.90, 6.95, 7.00, 7.05, 7.10, 7.15, 7.20, 7.25, 7.30, 7.35, 7.40, 7.45, 7 .50, 7.55, 7.60, 7.65, 7.70, 7.75, 7.80, 7.85, 7.90, 7.95, 8.00, 8.05, 8.10, 8.15, 8.20, 8.25, 8.30, 8.35, 8.40, 8.45, 8.50, 8.55, 8.60, 8.65, 8.70, 8 .75, 8.80, 8.85, 8.90, 8.95, 9.00, 9.05, 9.10, 9.15, 9.20, 9.25, 9.30, 9.35, 9.40, 9.45, 9.50, 9.55, 9.60, 9.65, 9.70, 9.75, 9.80, 9.85, 9.90, 9.95, 1 0.00, 10.05, 10.10, 10.15, 10.20, It may be 10.25, 10.30, 10.35, or 10.40, or a range between any two values listed herein. In some embodiments of the present application, the ratio of G" to G' (G"/G') ranges from 0.50 to 10.36. If the G" to G' ratio is lower than the suggested range, the adhesion of the film to the substrate is poor. On the other hand, if the G" to G' ratio is higher than the suggested range, wrinkles appear in the photoresist film and resin outflow occurs evenly, increasing the thickness. It becomes uneven and the etching accuracy becomes poor.

Provided that the above conditions regarding the ratio of G" to G' are met, the shear storage modulus G' at 30°C of the photoresist film is not particularly limited and can be adjusted as needed. Generally, the shear storage modulus at 30°C of the photoresist film is not limited, and can be adjusted as needed. The shear storage modulus (G') may range from 0.001 kPa to 4300 kPa. For example, the shear storage modulus (G') at 30° C. of the photoresist film may be 0.001 kPa, 0.005 kPa, 0.01 kPa, 0.05 kPa, 0.1 kPa. , 0.5 kPa, 1 kPa, 5 kPa, 10 kPa, 20 kPa, 30 kPa, 40 kPa, 50 kPa, 60 kPa, 70 kPa, 80 kPa, 90 kPa, 100 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, 350 kPa, 400 kPa, 450 kPa, 500 kPa, 550 kPa, 600 kPa, 650 kPa, 700 kPa, 750 kPa, 800 kPa, 850 kPa, 900 kPa, 950 kPa, 1000 kPa, 1050 kPa, 1100 kPa, 1150 kPa, 1200 kPa, 1250 kPa, 1300 kPa, 1350 kPa, 1400 kPa, 1450 kPa, 1500 kPa, 1550 kPa, 1600 kPa, 1650 kPa, 1700 kPa, 1750 kPa, 1800 kPa, 1850 kPa, 1 900 kPa, 1950 kPa , 2000 kPa, 2050 kPa, 2100 kPa, 2150 kPa, 2200 kPa, 2250 kPa, 2300 kPa, 2350 kPa, 2400 kPa, 2450 kPa, 2500 kPa, 2550 kPa, 2600 kPa, 2650 kPa, 2700 kPa, 2750 kPa, 2800 kPa, 2850 kPa, 2900 kPa, 2950 kPa, 3000 kPa, 3050 kPa, 3100 kPa, 3150 kPa, 3200 kPa, 3250 kPa, 3300 kPa, 3350 kPa, 3400 kPa, 3450 kPa, 3500 kPa, 3550 kPa , 3600 kPa, 3650 kPa, 3700 kPa, 3750 kPa, 3800 kPa, 3850 kPa, 3900 kPa, 3950 kPa, 4000 kPa, 4050 kPa, 4100 kPa, 4150 kPa, 4200 kPa, 4250 kPa, or 4300 kPa, or any two listed herein. It can be a range between values. If the G' value is lower than the lower limit of the suggested range, the photoresist film may have uneven thickness when subjected to external force. On the other hand, if the G' value is higher than the upper limit of the suggested range, the photoresist film is likely to crack when subjected to external force. In some embodiments of the present application, the photoresist film has a shear storage modulus G' at 30°C ranging from 10 kPa to 2100 kPa.

Provided that the above conditions regarding the ratio of G" to G' are met, the shear loss modulus G" at 30° C. of the photoresist film is not particularly limited and can be adjusted as necessary. Typically, the shear loss modulus G" at 30 °C of the photoresist film may range from 0.08 kPa to 1900 kPa. For example, the shear loss modulus G" at 30 °C of the photoresist film may be 0.08 kPa, 0.1 kPa, 0.5 kPa, 1 kPa, 5 kPa, 10 kPa, 20 kPa, 30 kPa, 40 kPa, 50 kPa, 60 kPa, 70 kPa, 80 kPa, 90 kPa, 100 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, 350 kPa, 400 kPa, 450 kPa, 500 kPa, 550 kPa, 600 kPa, 650 kPa, 700 kPa, 750 kPa, 800 kPa, 850 kPa, 900 kPa, 950 kPa, 1000 kPa, 1050 kPa, 1100 kPa, 1150 kPa, 1150 kPa , 1200 kPa, 1250 kPa, 1300 kPa, 1350 kPa, 1400 kPa, 1450 kPa, 1500 kPa, 1550 kPa, 1600 kPa, 1650 kPa, 1700 kPa, 1750 kPa, 1800 kPa, 1850 kPa, or 1900 kPa , or here It can be in the range between any two values listed. If the G" value is lower than the lower limit of the presented range, it is difficult to form a film. On the other hand, if the G" value is higher than the upper limit of the presented range, the thickness of the photoresist film may become uneven. In some embodiments of the present application, the shear loss modulus G" at 30° C. ranges from 140 kPa to 1860 kPa.

The shear loss modulus G" at 30 °C and the shear storage modulus G' at 30 °C are measured using a rheometer under the following operating conditions: the attachment is 25 mm parallel plate ETC aluminum, the mode is shear mode, and the immersion time is 0. seconds, the initial temperature is 30 °C, the ramp rate is 3 °C/min, the final temperature is 150 °C, the immersion time after the ramp is 0 seconds, the pressure is 1000 Pa, the measurement is made at a single point, and the frequency is 1 Hz. Detailed measurement methods are described in the Examples section below.

The ratio of the shear loss modulus at 30 °C, G", of the photoresist film to the shear storage modulus, G' at 30 °C (G"/G'), is used to control the proportion of residual solvent in the photoresist film, or to control the proportion of residual solvent in the photoresist film. It can be adjusted by controlling the components of the photoresist film, such as by controlling the type of resin, or by controlling the ratio between the resin and the crosslinking agent for producing the photoresist film. In general, the lower the ratio of residual solvent in a photoresist film, the lower the G"/G' value; the higher the glass transition temperature (Tg) of the resin or the higher the ratio of resin to crosslinker (i.e., the higher the ratio of resin to crosslinker). As the value increases, the G"/G' value decreases.

The photoresist film of the present application not only has excellent workability, adhesion performance, and appearance, but also has the advantage of being able to be formed to a high thickness. Generally, the photoresist film of the present application may have a thickness ranging from 60 μm to 600 μm, more specifically 65 μm to 400 μm. For example, the photoresist film of the present application has 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 115 μm, 120 μm, 125 μm, 130 μm, 135 μm, 140 μm, 145 μm, 150 μm, 155 μm, 160 μm, 165 μm, 170 μm, 175 μm, 180 μm, 185 μm, 190 μm, 195 μm, 200 μm, 205 μm, 210 μm , 215 μm, 220 μm, 225 μm, 230 μm, 235 μm, 240 μm, 245 μm, 250 μm, 255 μm, 260 μm, 265 μm, 270 μm, 275 μm, 280 μm, 285 μm, 290 μm, 295 μm, 300 μm, 305 μm, 310 μm, 315 μm, 320 μm, 325 μm, 330 μm, 335 μm, 340 μm, 345 μm, 350 μm, 355 μm, 360 μm, 365 μm, 370 μm, 375 μm, 380 μm, 385 μm, 390 μm, 395 μm, 400 μm, 405 μm, 410 μm, 415 μm, 420 μm, 425 μm, 430 μm, 435 μm, 440 μm, 445 μm, 450 μm, 455 μm, 460 μm , 465 μm, 470 μm, 475 μm, 480 μm, 485 μm, 490 μm, 495 μm, 500 μm, 505 μm, 510 μm, 515 μm, 520 μm, 525 μm, 530 μm, 535 μm, 540 μm, 545 thickness within the range of μm, 550 μm, 555 μm, 560 μm, 565 μm, 570 μm, 575 μm, 580 μm, 585 μm, 590 μm, 595 μm, or 600 μm, or between any two values listed herein. You can have it. In some embodiments of the present application, the photoresist film has a thickness ranging from 65 μm to 350 μm. A thicker photoresist film allows for a thicker metal conductive layer. Therefore, the photoresist film of the present application is particularly suitable for packaging of 2.5D and 3D integrated circuits for patterning before plating of the conductive layer and has a wider application range.

The photoresist film of the present application may be a positive photoresist film or a negative photoresist film. In some embodiments of the present application, the photoresist film of the present application is a negative photoresist film; That is, the developer will dissolve the portions of the photoresist film that have not been exposed to light, leaving behind the portions of the photoresist film that have been exposed to light.

1.2. Ingredients of photoresist film

The components of the photoresist film of the present application can be adjusted as needed, provided that the ratio of the shear loss modulus at 30° C. to the shear storage modulus G' at 30° C. satisfies the range of 0.50 to 10.40. In some embodiments of the present application, the photoresist film comprises a carboxyl-containing (meth)acrylic-based polymer and a photopolymerization initiator, or consists essentially of a carboxyl-containing (meth)acrylic-based polymer and a photopolymerization initiator, or is a carboxyl-containing (meth)acrylic-based polymer and a photopolymerization initiator. It is a negative photoresist film composed of a (meth)acrylic-based polymer and a photopolymerization initiator.

Here, the carboxyl-containing (meth)acrylic based polymer is a polymer or copolymer formed from (meth)acrylic acid based compound(s), or a copolymer formed from (meth)acrylic acid based compound(s) and another polymerizable compound(s). am. (meth)acrylic acid-based compounds refer to (meth)acrylic acid compounds containing vinyl group(s) (containing unsaturated double bonds) and carboxyl group(s) in the molecule, examples of which include acrylic acid and methacrylic acid. It is not limited to this. Each (meth)acrylic acid-based compound can be used alone or in combination. Other polymerizable compounds may be any compounds other than (meth)acrylic acid based compounds containing unsaturated double bond(s), such as vinyl-containing compound(s). Examples of such other polymerizable compounds include, but are not limited to, (meth)acrylate-based compounds and polyacrylamide. Examples of (meth)acrylate based compounds include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate. acrylate, isobutyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl acrylate, isotridecyl acrylate, o-phenylphenoxyethyl acrylate, lauryl acrylate, cyclic trimethylolpropane formal acrylate , isodecyl acrylate, octyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, 2-phenoxyethyl acrylate. No. The above-mentioned polymerizable compounds can be used alone or in any combination.

In a preferred embodiment of the present application, the carboxyl-containing (meth)acrylic based polymer is a copolymer formed from a (meth)acrylic acid based compound and a (meth)acrylate based compound. The (meth)acrylic acid-based compound may be acrylic acid, methacrylic acid, or a combination thereof. The (meth)acrylate-based compound may be selected from the group consisting of methyl methacrylate, butyl acrylate, 2-ethylhexyl acrylate, and combinations thereof. The weight ratio of (meth)acrylic acid-based compound to (meth)acrylate-based compound may range from 0.05 to 0.4. For example, the weight ratio of (meth)acrylic acid-based compound to (meth)acrylate compound can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4, or a range between any two values listed herein. there is.

Provided that the ratio of G" to G' of the photoresist film of the present application is satisfied, the molecular weight of the carboxyl-containing (meth)acrylic-based polymer contained in the photoresist film is not particularly limited. In general, the carboxyl-containing (meth)acrylic based polymer is not limited. ) The molecular weight of the acrylic-based polymer may be 30,000 to 200,000.For example, the molecular weight of the carboxyl-containing (meth)acrylic-based polymer may be 30,000, 35,000, 40,000, 45,000, 50,000, 55,000, 60,000, 65,000, 70, 000, 75,000, 80,000, 85,000, 90,000, 95,000, 100,000, 105,000, 110,000, 115,000, 120,000, 125,000, 130,000, 135,000, 140,000, 145,000, 150,000, 155,000, 160,000, 165,000, 170,000, 175,000, 180,000, 185,000, 190,000, 195,000, or 200,000 , or a range between any two values described herein, but the application is not limited thereto.

In the photoresist film of the present application, the type of photopolymerization initiator is not particularly limited, and may be any photopolymerization initiator known in the art. Examples of photopolymerization initiators known in the art include, but are not limited to, biimidazole-based compounds and Michler's ketone-based compounds. The amount of photopolymerization initiator in the photoresist film is also not particularly limited as long as it has the effect of promoting the desired polymerization reaction. Generally, the content of the photopolymerization initiator may be 0.5 to 15 parts by weight based on 100 parts by weight of the carboxyl-containing (meth)acrylic-based polymer. For example, the content of photopolymerization initiator is 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 for 100 parts by weight of carboxyl-containing (meth)acrylic based polymer. , 14, or 15 parts by weight, or a range between any two values set forth herein.

In some embodiments of the present application, the photoresist film is a negative photoresist film comprising the above-mentioned carboxyl-containing (meth)acrylic based polymer and a photopolymerization initiator, and further comprising a crosslinking agent. The cross-linking agent may be any conventional multifunctional unsaturated monomer known in the art. For example, the multifunctional unsaturated monomer can be a multifunctional acrylate based unsaturated monomer. Examples thereof are ethoxylated trimethylolpropane triacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, ethoxylated bisphenol-A diacrylate, polypropylene glycol diacrylate and dipentaerythritol hexamethylene. Including, but not limited to, acrylates. Provided that the conditions of the ratio of G" to G' of the photoresist film of the present application are met, the amount of the crosslinking agent in the photoresist film is not particularly limited as long as the desired crosslinking effect can be provided. In general, the amount of the crosslinking agent is The content may be 10 to 100 parts by weight based on 100 parts by weight of the carboxyl-containing (meth)acrylic-based polymer.For example, the content of the crosslinking agent may be 10, 15, or 100 parts by weight based on 100 parts by weight of the carboxyl-containing (meth)acrylic-based polymer. 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 parts by weight, or a range between any two values listed herein. there is.

In another preferred embodiment of the present application, the photoresist film is a negative photoresist film comprising the above-mentioned carboxyl-containing (meth)acrylic based polymer and a photopolymerization initiator, and further comprising the above-mentioned solvent and an optional crosslinking agent. . The solvent may be any inert solvent that can dissolve or disperse each component of the photoresist film but does not react with these components. Examples of solvents include, but are not limited to, tetrahydrofuran, ketone, methyl ethyl ketone, methyl acetate, ethyl acetate, propylene glycol monomethyl ether, methanol, ethanol, propylene glycol methyl ether acetate, and γ-butyrolactone. The above-mentioned solvents can be used alone or in any combination.

In addition to the optional and essential components mentioned above, the photoresist film of the present application may optionally include one or more additives known in the art. Examples of additives include, but are not limited to, dyes, pigments, radical inhibitors, and surfactants. Additives can be used alone or in any combination.

1.3. Manufacture of photoresist film

The manufacturing method of the photoresist film of the present application is not particularly limited. Those skilled in the art will be able to prepare photoresist films based on the disclosure of the description of this application. For example, when manufacturing the above-mentioned negative-type photoresist film, the photoresist film can be manufactured by the following process: each component of the photoresist film (carboxyl-containing (meth)acrylic-based polymer, photopolymerization uniformly mixing the initiator and other optional crosslinking agent(s) or additive(s) with a stirrer and dissolving or dispersing them in a solvent to provide a resin composition; After coating the resin composition on a substrate, drying the coated resin composition to obtain a photoresist film. Carboxyl-containing (meth)acrylic based polymers can be prepared by addition reaction of polymerizable compound(s) such as (meth)acrylic acid based compounds and (meth)acrylate compounds in the presence of a catalyst. Specific manufacturing methods are described in the examples below.

2. Application of photoresist film

Typically, each surface of the photoresist film will be covered with a protective layer before use to facilitate storage of the photoresist film and prevent damage and contamination by foreign substances. Accordingly, the present application also provides a composite film comprising the above-mentioned photoresist film of the present application and a protective film formed on at least one surface of the photoresist film. In a preferred embodiment of the present application, a protective film is formed on each surface of the photoresist film, and the material of the protective film formed on the surface of the photoresist film may be the same or different.

The type of protective film is not particularly limited and may be any conventional film known in the art. For example, the protective film may be selected from the group consisting of polyethylene terephthalate film (PET film), polyolefin film, and composites thereof. Examples of polyolefin films include, but are not limited to, polyethylene films (PE films) and polypropylene films (PP films), such as oriented polypropylene films. The composite may be a composite of a polyethylene terephthalate film and a polyolefin film or a composite of different polyolefin films. In one preferred embodiment of the present application, the composite film comprises a PET film formed on one surface of the photoresist film and a PE film formed on the other surface of the photoresist film.

The method for producing the composite film of the present application is not particularly limited and may be any method known in the art. Those skilled in the art will be able to prepare composite films based on the disclosure of the description of this application. For example, a composite film can be produced by stacking a protective film on both surfaces of a photoresist film to provide a laminate and compressing the laminate to obtain a composite film. Alternatively, the composite film may be formed by coating a resin composition for forming a photoresist film on a first protective film, drying the coated resin composition to form a photoresist film on the first protective film, and then forming a photoresist film on the first protective film. It can be prepared by adhering a second protective film onto the surface of the photoresist film that is not in contact with the film. Alternatively, the composite film is made by extruding a resin composition for forming a photoresist film into a position between two protective films spaced at a predetermined interval, then drying the extruded resin composition to form a photoresist film between the two protective films. It can also be manufactured by forming a resist film.

3. Examples

3.1. Test Methods

[Measurement of shear storage modulus G' and shear loss modulus G"]

The photoresist film was folded several times while removing air bubbles to prepare samples with a thickness of 1.2 mm to 1.4 mm. Measurements were performed on the samples using a rheometer (model: Discovery HR-2, TA instrument, Inc; Trios software version: 3.1.0.3538) with the following working conditions: the attachment port was a 25 mm parallel plate ETC. aluminum, the mode is shear mode, the immersion time is 0 seconds, the initial temperature is 30 ℃, the ramp rate is 3 ℃/min, the final temperature is 150 ℃, the immersion time after ramp is 0 sec, the pressure is 1000 Pa, the measurement is made at a single point, and the frequency is 1 Hz. The shear loss modulus G" at 30°C and the shear storage modulus G' at 30°C were recorded and the ratio of G" to G' (G"/G') was calculated.

[Wrinkle test of photoresist film]

The prepared composite film was wound on a slit roll with a length of 30 m and a width of 300 mm and placed at a temperature of 23° C. to 27° C. for 1 hour. After that, the 5 m long composite film was removed from the slit roll, and the PE protective film of the composite film was peeled. Afterwards, the surface of the removed 3 m to 5 m photoresist film was observed with the naked eye, and the number of wrinkles with a length of 10 mm or more and a width of 1 mm or more was recorded.

[100-grid adhesion test of photoresist film]

100-grid adhesion testing of photoresist films was performed in the following manner according to ASTM D3359. A copper clad laminate with a thickness of 1.6 mm (manufactured by Chang Chun Plastics Co., Ltd.; model: CCP-308) - the copper foil thickness of the copper clad laminate was 35 μm - was prepared. The copper clad laminate was brush ground using a #320 nonwoven brush wheel and a #600 nonwoven brush wheel, and the copper foil surface temperature of the copper clad laminate was adjusted to 50°C. After peeling off the PE protective film on the surface of the manufactured composite film, the photoresist film along with the PET protective film was stacked on the copper foil surface so that the photoresist film faces the copper foil surface of the copper clad laminate, and then laminated with a laminator to prepare the sample. provided. The stacking temperature was 80°C, the stacking pressure was 3.0 kg/cm2, and the stacking speed was 2.0 m/min. The PET film on the sample was peeled off, and the photoresist film of the sample was cut into 100 10×10 square grids at intervals of 1 mm to 1.2 mm using a blade. A transparent tape produced by 3M (model name: 3M Transparent 600) was attached to the photoresist film surface in a grid. The tape was then quickly peeled off at a 45 degree angle with respect to the substrate. The number of grids in which the photoresist film was peeled relative to the entire grid was calculated and recorded as a percentage.

[Resin leak test]

A 1.6 mm thick copper clad laminate with a copper foil thickness of 35 μm was manufactured. The copper clad laminate was brush ground using a #320 nonwoven brush wheel and a #600 nonwoven brush wheel, and the copper foil surface temperature of the copper clad laminate was adjusted to 50°C. After peeling off the PE protective film on the surface of the prepared composite film, the photoresist film was stacked with the PET protective film on the copper foil surface so that the photoresist film faced the copper foil surface of the copper clad laminate, and then laminated with a laminator. The stacking temperature was 80°C, the stacking pressure was 3.0 kg/cm2, and the stacking speed was 2.0 m/min. During lamination, it was observed with the naked eye to check whether the resin was flowing out from the edge of the photoresist film. If resin leaks, it is determined that a resin leak has occurred.

3.2. Manufacturing and testing of photoresist films

3.2.1. Synthesis of carboxyl-containing (meth)acrylic-based polymers

[Synthesis Example 1]

As copolymerization monomers, 15 g of methacrylic acid, 60 g of methyl methacrylate, and 25 g of butyl acrylate were mixed with 0.5 g of azobisoheptylnitrile to prepare solution a1. Solution b1 was prepared by dissolving 0.5 g of azobisoheptylnitrile in 20 g of ethyl acetate solvent. A flask equipped with a stirrer, reflux condenser, thermometer, and pipette was prepared, and 80 g of ethyl acetate was added to the flask and heated to 70°C. Next, solution a1 was added dropwise to the flask at a constant rate within 3 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 2 hours. After that, solution b1 was added dropwise to the flask at a constant rate within 0.5 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 5 hours. Afterwards, the solution in the flask was heated to 90°C and stirred for 5 hours to ensure that the reaction was sufficiently performed. After completion of the reaction, the product was cooled to room temperature to obtain carboxyl-containing (meth)acrylic-based polymer A (hereinafter also referred to as “polymer A”) with a weight average molecular weight of 55,000 and a solid content of 50% by weight.

[Synthesis Example 2]

As copolymerization monomers, 15 g of methacrylic acid, 65 g of methyl methacrylate, and 20 g of butyl acrylate were mixed with 0.43 g of azobisoheptylnitrile to prepare solution a2. Solution b2 was prepared by dissolving 0.5 g of azobisoheptylnitrile in 20 g of ethyl acetate solvent. A flask equipped with a stirrer, reflux condenser, thermometer, and pipette was prepared, and 80 g of ethyl acetate was added to the flask and heated to 70°C. After that, solution a2 was added dropwise to the flask at a constant rate within 3 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 2 hours. Afterwards, solution b2 was added dropwise to the flask at a constant rate within 0.5 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 5 hours. Afterwards, the solution in the flask was heated to 90°C and stirred for 5 hours to ensure sufficient reaction. After completion of the reaction, the product was cooled to room temperature to obtain carboxyl-containing (meth)acrylic-based polymer B (hereinafter also referred to as “polymer B”) with a weight average molecular weight of 65,000 and a solid content of 45% by weight.

[Synthesis Example 3]

As a copolymerization monomer, 20 g of methacrylic acid, 40 g of methyl methacrylate, and 40 g of 2-ethylhexyl acrylate were mixed with 0.5 g of azobisoheptylnitrile to prepare solution a3. Solution b3 was prepared by dissolving 0.5 g of azobisoheptylnitrile in 20 g of ethyl acetate solvent. A flask equipped with a stirrer, reflux condenser, thermometer, and pipette was prepared, and 80 g of ethyl acetate was added to the flask and heated to 70°C. After that, solution a3 was added dropwise to the flask at a constant rate within 3 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 2 hours. Thereafter, solution b3 was added dropwise to the flask at a constant rate within 0.5 hours, and the solution in the flask was maintained at a temperature of 70° C. and stirred for 5 hours. Afterwards, the solution in the flask was heated to 90°C and stirred for 5 hours to ensure sufficient reaction. After completion of the reaction, the product was cooled to room temperature to obtain carboxyl-containing (meth)acrylic-based polymer C (hereinafter also referred to as “polymer C”) with a weight average molecular weight of 55,000 and a solid content of 50% by weight.

3.2.3. Manufacture of photoresist film

Information on the raw materials used in the following examples and comparative examples is shown in Table 1 below.

Raw Material List Raw material explanation polymer A Carboxyl-containing (meth)acrylic-based polymer A prepared in Synthesis Example 1 polymer B Carboxyl-containing (meth)acrylic-based polymer B prepared in Synthesis Example 2 polymer C Carboxyl-containing (meth)acrylic-based polymer C prepared in Synthesis Example 3 3EO TMPTA Crosslinking agent, ethoxylated trimethylolpropane triacrylate, CAS number: 28961-43-5 BCIM-HABI Photopolymerization initiator, 1,2'-bis(2-chlorophenyl)-tetraphenyl biimidazole, CAS number: 7189-82-4 EABF Photopolymerization initiator, 4,4'-bis(diethylamino)-benzophenone, CAS number: 90-93-7 C.I.42040 Dye, brilliant green, bisulfate, CAS number: 633-03-4 THF Solvent, tetrahydrofuran, CAS number: 109-99-9

The ingredients were mixed in the ratios shown in Tables 2-1 to 2-3 and mixed uniformly by stirring for 1 hour to obtain a resin composition. The resin composition was coated on the PET film serving as a protective film using a Kodaira wire-wound rod according to the coating and drying conditions shown in Tables 2-1 to 2-3. Then, the coated resin composition was dried in an oven. Thereafter, the surface of the dried resin composition was covered with a PE film serving as a protective film to obtain a photoresist film (i.e., composite film) covered with the protective film of each of Examples 1 to 9 and Comparative Examples 1 to 5.

3.2.4. Testing of photoresist films

The photoresist films of Examples 1 to 9 and Comparative Examples 1 to 5 were tested according to the above-described test methods, including shear storage modulus G' and shear loss modulus G" test, 100-grid adhesion test, wrinkle test and resin runoff test. And the results are summarized in Table 3-1 to Table 3-3.

As shown in Tables 3-1 to 3-3, the photoresist film of the present application has a low peeling rate, that is, excellent adhesion to the substrate. The photoresist film of the present application also has an excellent appearance since no wrinkles were observed. In addition, the workability is excellent because no resin leakage occurs during the work of the photoresist film of this application. In contrast, as shown in Comparative Examples 1 and 2, when the ratio of shear loss modulus G" at 30 °C to shear storage modulus G' at 30 °C is less than 0.50, the adhesion of the photoresist film is poor and much worse in the 100-grid test. In addition, as shown in Comparative Examples 3 to 5, when the ratio of the shear loss modulus G" at 30 ° C to the shear storage modulus G' at 30 ° C exceeds 10.40, the photoresist film has wrinkles. Therefore, the appearance is poor. If the ratio of the shear loss modulus G" at 30 ℃ to the shear storage modulus G' at 30 ℃ is greater than 10.50 (Comparative Examples 3 and 4), the photoresist film even has the problem of resin leakage during operation, that is, the workability of the photoresist film is reduced. This is not good and is not suitable for actual use.

The above examples illustrate the principles and effects of the present application and reveal the original features of the present application. Those skilled in the art will be able to make various modifications and substitutions based on the teachings and suggestions of the invention described. Accordingly, the scope of protection of this application is as defined in the claims that follow.

Claims (10)

It has a shear loss modulus G" at 30° C. and a shear storage modulus G' at 30° C., wherein the ratio of G" to G'(G"/G') is between 0.50 and 10.40. range,
The shear loss modulus G" at 30 °C and the shear storage modulus G' at 30 °C were measured using a rheometer under the following operating conditions: attachment is 25 mm parallel plate ETC aluminum, mode is shear mode, immersion. The time is 0 s, the initial temperature is 30 °C, the ramp rate is 3 °C/min, the final temperature is 150 °C, the post-ramp immersion time is 0 s, the pressure is 1000 Pa, the measurement is made at a single point, , the frequency is 1 Hz,
Photoresist film, a negative photoresist film. The photoresist film of claim 1, wherein the ratio of G" to G' ranges from 0.50 to 10.36. The photoresist film of claim 1, wherein the shear storage modulus G' at 30°C is from 0.001 kPa to 4300 kPa and the shear loss modulus G" at 30°C is from 0.08 kPa to 1900 kPa. 4. The photoresist film according to any one of claims 1 to 3, wherein the thickness ranges from 60 μm to 600 μm. 5. The photoresist film of claim 4, wherein the thickness ranges from 65 μm to 400 μm. The photoresist film of claim 1, comprising a carboxyl-containing (meth)acrylic based polymer and a photopolymerization initiator. The photoresist film of any one of claims 1 to 3; and
A composite film comprising a protective film formed on at least one surface of the photoresist film. The composite film according to claim 7, wherein the protective film is selected from the group consisting of polyethylene terephthalate film, polyolefin film, and composites thereof. delete delete