KR20060086680A - Compositions of negative type liquid photoresist - Google Patents

Abstract

The present invention relates to a negative liquid photoresist composition, and more particularly to a negative liquid photoresist composition comprising a binder polymer, an ethylenically unsaturated compound, a photopolymerization initiator and a slip improver.

In the negative liquid photoresist composition of the present invention, the surface slip characteristics are improved by adding polyether-modified polydimethylsiloxane as a slip improver, thereby improving workability and productivity in a manufacturing process.

Negative liquid photoresist, slip improver

Description

Composition of negative type liquid photoresist {COMPOSITIONS OF NEGATIVE TYPE LIQUID PHOTORESIST}

The present invention relates to a negative type liquid photoresist composition, and more particularly, polyether modified polydimethylsiloxane as a slip improver. The present invention relates to a high resolution negative liquid photoresist composition capable of improving surface slip characteristics, thereby improving workability and productivity in a manufacturing process.

High density and high adhesion negative liquid photoresist is required to make such circuit shape by increasing density of printed circuit board (PCB, PCB) and high density of semiconductor packaging technology. . In addition, the negative liquid photoresist should have excellent surface properties with controlled surface slip characteristics in consideration of the workability and productivity of PCB manufacturing technicians, and also roll coating or dip coating liquid materials on the substrate. Since the coating method is used, the liquid should be uniformly coated and there should be no coating defects such as pinholes.

Negative liquid photoresist is characterized by higher fine wire adhesion and resolution than dry film, but many existing negative liquid photoresist products do not have fine wire adhesion or resolution much better than dry film. (Order change)

In the physical properties after exposure and development, the thin wire adhesion and the resolution are opposite to each other. This is because, in order to increase the fine wire adhesion, the fine width line exposed while the unexposed part is completely washed out at the time of development should be stuck without falling from the copper layer even with a small exposure amount.

On the other hand, in order to increase the resolution, the unexposed part adjacent to the exposed part should be removed quickly under the development conditions. If the viscosity of the resist is high or very high sensitivity, the resolution is reduced because the resist is not removed quickly at the boundary part. That is, only when the boundary between the exposed portion and the unexposed portion has a large difference in developability under a certain developing condition, a resist having excellent fine wire adhesion and resolution can be simultaneously produced. In order to satisfy these physical properties at the same time, a resist composition composed of a binder polymer or the like should be made to have excellent adhesiveness with respect to the copper plate and have proper developability when contacted with a developer.

In order to solve these technical problems and improve fine line adhesion and resolution, US, 6,037,100, 6,271,595, 6,103,449, 5,935,761, 6,037,100, 6,271,595, 6,103,449, 5,935,761 In order to show such physical properties, these patents introduce new raw material components, chemical structural changes of existing raw materials, and methods for optimizing the composition ratio of these ingredients.

However, even in these technologies, the slip property of the surface after coating and drying the negative liquid photoresist is poor, which makes it difficult to align the artwork with the substrate during the exposure process. It is difficult to apply in. In addition, the scratch on the resist coating caused by a large number of rolls in the PCB production process causes the circuit to open, which significantly affects the production yield.

In addition, the negative liquid photoresist not only has poor coating property but also defects such as pinholes, surface slip characteristics, and many scratches have occurred due to numerous rolls during the process. In order to solve this problem, many researches are being conducted, but at present, there is no solution, so the process is required to change the process in accordance with the production expectation, which requires a lot of time in the process.

An object of the present invention is to provide a high-resolution negative liquid photoresist composition with improved surface slip characteristics to solve the above technical problems.                         

In addition, an object of the present invention is to provide a negative liquid photoresist composition having excellent resolution and fine wire adhesion, and excellent in surface slipability in the process and excellent in productivity and workability.

The object of the present invention can be embodied from the following description.

The negative liquid photoresist composition of the present invention for solving the above problems is (a) binder polymer (b) polymer, (b) ethylenically unsaturated compound, (c) photoinitiator and (d) for improving the slipperiness It is characterized by containing a polyether modified polydimethylsiloxane as a slip improver.

Hereinafter, each composition of the negative liquid photoresist of this invention is explained in full detail.

(a) binder polymer

Hereinafter, the binder polymer of the negative liquid photoresist composition constituents of the present invention and the monomers used to synthesize the same will be described.

The binder polymer serves to impart mechanical strength and adhesiveness of the photopolymerization composition, and examples thereof include acrylic polymers, polyesters, polyurethanes, and the like.

Among them, a methacrylic copolymer (copolymer with ethylenically unsaturated carboxylic acid or other monomer if necessary), which is a kind of acrylic polymer, is important. Methacrylic copolymer containing acetoacetyl group can be used. The methacrylic monomers usable for synthesizing the methacrylic copolymers include methyl methacrylate, ethyl methacrylate, propylmethacrylate, and butyl methacrylate. Hexylmethacrylate, 2-ethylhexylmethacrylate, cyclohexylmethacrylate, benzylmethacrylate, dimethylaminoethyl methacrylate , Hydroxyethyl methacrylate (hydroxyethylmethacrylate), hydroxypropylmethacrylate (hydroxypropylmethacrylate), glycidyl methacrylate (glycidyl methacylate) and the like.

Among ethylenically unsaturated carboxylic acids, monoacrylic acids such as acrylic acid, methacrylic acid, and crotonic acid are widely used. Maleic acid, fumaric acid, dicarboxylic acids such as itaconic acid, or anhydrides thereof, half esters, and the like may also be used. Of these, acrylic acid and methacrylic acid are particularly used and exhibit excellent physical properties. In the case of weak alkali developing photoresist resin, the amount of ethylenically unsaturated carboxylic acid is used in an amount of 15-30% by weight (acid value: 100-200 mg KOH / g).

Other monomers that can be copolymerized with them are acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, styrene, α-methylstyrene -methylstyrene, vinyl acetate, alkyl vinyl ether, etc. are mentioned.

Generally, the negative liquid photoresist is dried at 110 ° C. for about 10 minutes, and the resist should be very hard so that the resists do not stick together even when several substrates are stacked after storage. In general, the hardness of the liquid photoresist after drying should have a value of 2H or more.

In order for the hardness of the resist to have a value of 2H or more after drying, the glass transition temperature (Tg) of the binder polymer should be at least 100 ° C or higher. This is because the overall photoresist composition contains a large amount of low-molecular compounds such as monomolecules and oligomers as well as binder polymers, and thus the glass transition temperature of the entire composition in which they are mixed together is much lower than that of the base polymer alone.

If the glass transition temperature of the binder polymer is too high, the resist is too hard to break, peeling may occur during etching, and underplating defects may occur during plating. On the other hand, if the glass transition temperature of the binder polymer is too low, there is a problem that the hardness of the resist is lowered.

In the present invention, the binder polymer having various glass transition temperatures is used to make a composition, and then hardness is selected to select an optimum binder polymer.

The molecular weight and acid value as well as the glass transition temperature are very important when selecting the binder polymer. If the molecular weight is too small, fine wire adhesion and etching resistance may be weakened. On the other hand, if the molecular weight is too high, the developing speed will be slow and the resolution will be poor. If the acid value is too small, there is a problem in development, and if the acid value is too high, the developing speed becomes too fast. Therefore, it is necessary to design the binder polymer in accordance with conditions such as molecular weight, glass transition temperature, acid value, etc. of the binder polymer in order to obtain a suitable developing speed and resolution, hardness after drying.

Binder polymer used in the present invention is a polymer in which the acrylate is dissolved in 1-methoxy-2-propanol solvent, the glass transition temperature is 100 ℃ to 150 ℃, the acid value is 40 to 130 mgKOH / g, the weight average molecular weight was used 20,000 to 60,000.

The binder polymer is 35 to 88.9% by weight based on the total composition.

(b) ethylenically unsaturated compounds

Hereinafter, the ethylenically unsaturated compound in the photoresist composition of the present invention will be described.

The ethylenically unsaturated compound includes a polyfunctional monomer and a monofunctional monomer. As the polyfunctional monomer, ethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, propylene glycol dimethacrylate ( propylene glycol dimethacrylate), propylene glycol dimethacrylate, butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexane glycol Dimethacrylate (1,6-hexane glycol dimethacrylate), trimethololpropane trimethacrylate, glycerin dimethacrylate, pentaerythritol dimethacrylate, Pentaerythritol trimethacrylate, dipenta Dipentaerythritol pentamethacrylate, 2,2-bis (4-methacryloxydiethoxyphenyl) propane [2,2-bis (4-methacryloxydiethoxyphenyl) propane], 2-hydroxy-3-methacryl Royloxypropyl methacrylate (2-hydroxy-3-methacryloyloxypropyl methacrylate), ethylene glycol diglycidyl ether dimethacrylate, ethylene glycol diglycidyl ether dimethacrylate (diethylene glycol diglycidyl ether dimethacrylate) diethylene glycol diglycidyl ether dimethacrylate, phthalic acid diglycidyl ester dimethacrylate, glycerin polyglycidyl ether polymethacrylate, and the like.

In addition to the polyfunctional monomer, a monofunctional monomer may be used in an appropriate amount. Examples of monofunctional monomers include 2-hydroxyethyl methacrylate, 2-hydroxypropylmethacrylate, 2-hydroxybutyl methacrylate, 2- 2-phenoxy-2-hydroxypropyl methacrylate, 2-methacryloyloxy-2-hydroxypropyl phthalate, 3-chloro 2-hydroxypropyl methacrylate, glycerin monomethacrylate, 2-methacryloyloxyethyl acid phosphate, phthalic acid phthalic acid derivatives, methacrylate, and N-methylol methacrylamide.

The ethylenically unsaturated compound is used in 10 to 50% by weight based on the total composition. If the amount of the ethylenically unsaturated compound is used less than 10% by weight of the total composition, less photocuring occurs, the flexibility of the resist is reduced, and the developing speed is also slowed. On the other hand, when the amount of the ethylenically unsaturated compound is used more than 50% by weight based on the total composition, the viscosity and cold flow of the crude liquid increases and the peeling rate is slowed.

(c) photopolymerization initiator

Photoinitiators include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzyl diphenyl disulfide, benzyl dimethyl ketal, anthraquinone, naphthoquinone, 3, 3-dimethyl-4-methoxybenzophenone, benzophenone, p, p'-bis (dimethylamino) benzophenone (p, p'-bis (diethylamino) benzophenone, p, p'-diethylaminobenzo Phenone, pivalon ethyl ether, 1,1-dichloro acetophenone, pt-butyldichloroacetophenone, dimer of hexaaryl-imidazole, 2,2'-diethoxyacetophenone, 2,2'-diethoxy-2 -Phenylacetophenone, 2,2'dichloro-4-phenoxyacetophenone, phenylglyoxylate, a-hydroxy-isobutylphenone, dibenzospan, 1- (4-isopropylphenyl) -2-hydroxy 2-methyl-1-propanone, 2-methyl- [4- (methylthio) fetyl] -2-morpholino-1-propanone, tribromomethylphenylsulfone, and the like .

The photoinitiator uses 1 to 10% by weight based on the total composition.

(d) polyether modified polydimethylsiloxane

As the most important constituent of the present invention, polyether modified polydimethylsiloxane is added to provide a composition having excellent surface slip characteristics, that is, slipperiness, and includes at least one material represented by the following Chemical Formulas 1 and 2.

However, when the content of the compound in the negative liquid photoresist exceeds 5% by weight relative to the total composition, the surface of the resist coating film is too hard, and when less than 0.1% by weight, there is no slip fragrance effect. The amount is suitably used in an amount of 0.1 to 5% by weight based on the total composition.

(e) other additives

In the negative liquid photoresist composition of the present invention, a volatile organic substance, a softening agent, or the like may be added.

Volatile organics are compatible with other compositions of the photoresist and should not interfere with film formability when coating the photoresist composition. Representative examples are those such as plasticizers used as softening agents such as vinyl chloride resin.

Phthalic acid esters used as softening agents are, for example, dimethyl phthalate, diethyl phthalate, dibutylthphthalate, diheptyl phthalate, and dioctylphthalate. (dioctyl phthalate), diisodecyl phthalate, butylbenzyl phthalate, diisononyl phthalate, ethylphthalylethyl glycolate, dimethyl isophthalate, dichlorol Hexyl phthalate and the like, and esters of fatty acids or adipic acid, such as dioctyl adipate, diisobutyl adipate, dibutyl adipate ( dibutyl adipate, diisodecyl adipate, dibutyl diglycol ad ipate), dibutyl sebacate, dioctyl sebacate, and the like.

Other Softeners Glycerol Triacetate, Trimethyl Phosphate, Triethyl Phosphate, Tributyl Phosphate, Trioctyl Phosphate, Tributoxyethyl Phosphate, Tris-Chloroethyl Phosphate, Tris-Dichloropropyl Phosphate, Triphenyl Phosphate, Tricresyl Phosphate, Tri Xylenyl phosphate, octyl diphenyl phosphate, xylenyldiphenyl phosphate, triloryl phosphate, tricetyl phosphate, tristearyl phosphate, trioleyl phosphate, triphenylphosphite, tris tridecyl phosphite, dibutyl hydride Rosen phosphite, dibutyl-butyl phosphonate, di (2-ethylhexyl) phosphonate, 2-ethylhexyl-2-ethylhexyl phosphonate, methyl phosphate, isopropyl acid phosphate, butyric acid phosphate, di Butyric Acid Phosphate, Monobutyl Acid Phosphate, Tilsan may be used such as phosphate, dioctyl phosphate, isopropyl phosphate used acids, mono isodecyl phosphate, decamethylene nolsan phosphate.

As the softening agent, volatile organic compounds such as glycerin, trimethylolpropane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and dipropylene glycol can be used, and lower alkyl ethers, lower fatty acid esters, higher fatty acids and their Esters, higher fatty alcohols or esters thereof can also be used.

Hereinafter, examples of the present invention will be described in more detail, but the scope of the present invention is not limited to these examples.

<Examples 1-10>

In the present invention, a negative liquid photoresist having a thickness of 10 microns after drying and having a composition from Example 1 to Example 10 in the following [Table 1] and [Table 2] was prepared. At this time, a product (BYK-330, BYK-335) commercially available from BYK was used as the polyether-modified polydimethylsiloxane as the slip improver.

The manufacturing conditions were a negative liquid photoresist prepared by the above formulation at a temperature of 23 ± 2 ℃ dip coating on a 600mm × 400mm PCB substrate by roll coating at a line speed of 1.8 mm / sec, the temperature of 80 ℃ After drying for 10 minutes at 5 kW with a scattering light exposure machine Perkin-ElmerTM OB712 using Kolon artwork, a high resolution artwork without a protective neomask.

After coating on the PCB, the exposed negative liquid photoresist was left for 20 minutes and then sprayed at 30 ± 1 ° C with 1.0 wt% aqueous sodium carbonate (Na ₂ CO ₃ ) solution as the developer and spray pressure of 1.0 kgf / cm2. The breakpoint was developed at 50%.

In summary, it is as follows.

Workshop temperature: 23 ± 2 ℃

PCB base size: 600mm × 400mm

Dip Coating: Line Speed 1.8 mm / sec

Drying: 80 ° C for 10 minutes

Scattered Light Exposure Machine: Perkin-ElmerTM OB7129 (5kW)

Exposure dose: Exposure dose under artwork and exposure machine Myler film

Sensitivity: 21 steps

Artwork: High resolution artwork without protective neomask

Developer: 1.0 wt% Na ₂ CO ₃

Temperature: 30 ± 1 ℃

Break point: 50%

Developer spray pressure: 1.0 kgf / cm2

ingredient Product name (or ingredient name) Content (weight g) Example 1 Example 2 Example 3 Example 4 Example 5 Comparative example Binder Polymer Acrylate polymer dissolved in 1-methoxy-2-propanol solvent 24 24 24 24 24 24 Photopolymerization Initiator Benzophenone (Aldrich Chemical) 2.0 2.0 2.0 2.0 2.0 2.0 4,4- (bisdiethylamino) benzophenone (Aldrich Chemical) 1.5 1.5 1.5 1.5 1.5 1.5 Toluenesulfonic Acid Monohydrate (Aldrich Chemical) 3.0 3.0 3.0 3.0 3.0 3.0 Diamond Green GH (Japan Hodogaya Co.) 0.5 0.5 0.5 0.5 0.5 0.5 Photopolymerization monomer APG-400 (Miwon Corporation) 5.5 5.5 5.5 5.5 5.5 5.5 BPE-500 (Miwon Corporation) 3.4 3.4 3.4 3.4 3.4 3.4 Slip improver BYK -330 as a substance corresponding to Chemical Formula 1 0.1 0.5 1.0 2.0 5.0 - solvent 1-methoxy-2-propanol (Aldrich Chemical, 99%) 60.0 59.6 59.1 58.1 55.1 60.1 Sum 100.0 100.0 100.0 100.0 100.0 100.0

ingredient Product name (or ingredient name) Content (weight g) Example 6 Example 7 Example 8 Example 9 Example 10 Comparative example Binder Polymer Acrylate polymer dissolved in 1-methoxy-2-propanol solvent 24 24 24 24 24 24 Photopolymerization Initiator Benzophenone (Aldrich Chemical) 2.0 2.0 2.0 2.0 2.0 2.0 4,4- (bisdiethylamino) benzophenone (Aldrich Chemical) 1.5 1.5 1.5 1.5 1.5 1.5 Toluenesulfonic Acid Monohydrate (Aldrich Chemical) 3.0 3.0 3.0 3.0 3.0 3.0 Diamond Green GH (Japan Hodogaya Co.) 0.5 0.5 0.5 0.5 0.5 0.5 Photopolymerization monomer APG-400 (Miwon Corporation) 5.5 5.5 5.5 5.5 5.5 5.5 BPE-500 (Miwon Corporation) 3.4 3.4 3.4 3.4 3.4 3.4 Slip improver BYK 350 as a substance corresponding to Chemical Formula 2 0.1 0.5 1.0 2.0 5.0 - solvent 1-methoxy-2-propanol (Aldrich Chemical, 99%) 60.0 59.6 59.1 58.1 55.1 60.1 Sum 100.0 100.0 100.0 100.0 100.0 100.0

Comparative Example

The comparative example of the present invention excludes only the slip improver from the components and component ratios of Examples 1 to 10.

Negative liquid photoresists were prepared with the compositions of the above examples and comparative examples, and their physical properties were examined.

Surface hardness was measured by a pencil hardness tester, and quantification data on slip characteristics were measured by a TOYOOSEIKI Plane Surface Friction Tester.

Test results of the PCB (Printed Circuit Board) manufactured by the composition of the above Examples and Comparative Examples are shown in Table 3 below.

Slip Hardness after drying Static Friction Coefficient after Drying Kinetic friction coefficient after drying Post-exposure static friction coefficient Post-exposure Kinetic Friction Coefficient Example 1 Great 1H 0.05 0.2 0.005 0.008 Example 2 Great 2H 0.33 0.5 0.031 0.05 Example 3 Great 2H 0.07 0.22 0.09 0.02 Example 4 Great 3H 0.35 0.48 0.04 0.05 Example 5 Great 3H 0.23 0.36 0.02 0.04 Example 6 Great 2H 0.09 0.24 0.01 0.03 Example 7 Great 2H 0.08 0.22 0.01 0.009 Example 8 Great 2H 0.25 0.39 0.03 0.02 Example 9 Great 3H 0.36 0.48 0.04 0.03 Example 10 Great 3H 0.22 0.39 0.02 0.015 Comparative example Bad 2H 0.55 0.65 0.06 0.09

In the case of the negative liquid photoresist to which the polyether-modified polydimethylsiloxane of the present invention is added as a slip improver as shown in [Table 3] above, the static friction coefficient, the motion friction coefficient and the post-exposure stop after drying than the photoresist of the comparative example It can be seen that the slip characteristics are improved by decreasing the friction coefficient and the motion friction coefficient. However, if the content of the compound in the negative liquid photoresist is too large, there is a disadvantage that the surface of the resist coating film is too hard, the amount is suitably 0.1-5% by weight relative to the total composition.

The present invention uses an appropriate amount of polyether-modified polydimethylsiloxane as a negative liquid photoresist as an additive for improving slip property, compared to the photoresist of the conventional composition, the static friction coefficient after drying, the coefficient of motion friction and the static friction coefficient after exposure, and the motion friction The coefficient is reduced to have excellent slip characteristics, and the scratch by the roll is reduced to improve productivity and workability in the process of manufacturing a printed circuit board using the negative liquid photoresist of the present invention.

Claims (7)

In the negative liquid photoresist composition comprising a binder polymer, an ethylenically unsaturated compound, a photopolymerization initiator, A negative type liquid photoresist composition comprising polyether modified polydimethylsiloxane as a slip improver. The method of claim 1, The polyether modified polydimethylsiloxane is a negative liquid photoresist composition, characterized in that the material represented by the formula (1). [Formula 1]

The method of claim 1, The polyether-modified polydimethylsiloxane is a negative liquid photoresist composition, characterized in that the material represented by the formula (2). [Formula 2]

The method of claim 1, The polyether-modified polydimethylsiloxane is a negative liquid photoresist composition, characterized in that the mixture of the material represented by the formula (1) and the material represented by the formula (2). The method of claim 1, The polyether-modified polydimethylsiloxane is negative type liquid photoresist composition, characterized in that it comprises 0.1 to 5% by weight based on the total composition. The method of claim 1, The binder polymer is a negative type liquid photoresist composition, characterized in that the acrylate polymer dissolved in 1-methoxy-2-propanol solvent. The method of claim 6, The acrylate polymer has a glass transition temperature of 100 ℃ to 150 ℃, the acid value (acid value) is 40 to 130 mgKOH / g, the weight average molecular weight of 20,000 to 60,000, characterized in that the negative liquid photoresist composition.