KR20120044837A - Multilayer film - Google Patents

Abstract

PURPOSE: A multilayered film is provided not to have damage of a resin protection layer at removing a support film while bonding the support film and the resin protection layer at moderate level. CONSTITUTION: A multilayered film comprises a support film, a release layer, and a resin protection layer laminated in order. The release layer comprises one or more kinds selected from a silicon resin, a fluorine resin, and aliphatic wax. The resin protection layer comprises polyvinylalcohol or polyethylene glycol of which weight average molecular weight is 5,000-300,000. The adhesive force between the release layer and the protective layer is 0.0005-0.01 N/cm. The haze of the protection layer is 3.0% or less, and the development time per 1um is 10 seconds or shorter.

Description

Multilayer Film {MULTILAYER FILM}

The present invention relates to a multilayer film having a multilayer structure.

Dry film photoresist has been used as an important material for the current electrical and electronics industry, especially printed circuit boards, since it was developed under the name 'RISTON' by DuPont in 1968.

About 50% of photoresist is used as a photoresist material for forming circuits on printed circuit boards, but dry film photo is used for the production of printed circuit boards of double-sided and multilayer boards requiring high density and high reliability. Resist is essentially used.

Such dry film photoresist is mainly laminated in a two-layer structure of a base film and a photosensitive layer, and further includes a protective film to protect the photoresist until use of the dry film photoresist. .

Generally, the support film uses a polyester film such as polyethylene terephthalate, and its thickness is about 25 μm. Such a support film serves as a support of the photoresist during the manufacture of the dry film photoresist, to facilitate handling during exposure of the photoresist having adhesive force.

Photosensitive resin is divided into negative type and positive type by the reaction mechanism by light. In the case of negative type photosensitive resin, photocrosslinking reaction occurs at the exposed part, and unexposed part is washed with alkali, leaving a resist pattern. In the case of the photosensitive resin, a photolysis reaction occurs at an exposure site and is developed in an alkali, and an unexposed site remains to form a resist pattern.

The photoresist is prepared to suit the purpose including a photopolymerizable monomer, a photopolymerization initiator, a binder polymer and the like. Such photoresist is applied on a support film and has a thickness of from 15 to 100 mu m, after application, to suit the purpose of use. Such photoresists have various compositions depending on the mechanical and chemical properties and processing conditions required for the photoresist.

On the other hand, the protective film prevents damage to the resist during handling and serves as a protective cover to protect the photoresist from foreign substances such as dust, and is laminated on the back surface where the support film of the photoresist is not formed.

As an example of a pattern forming method using such a dry film photoresist, a protective film is first peeled off and laminated on a copper clad laminate (CCL) when applied to a printed circuit board, followed by a mask having a desired pattern. Is exposed by irradiation with ultraviolet (UV) light and then developed using a suitable solvent to wash away the uncured parts.

In general, in the case of using a dry film photoresist having such a composition, since the support film is attached to the photoresist during exposure, the photoresist and the mask are spaced apart by the thickness of the support film, resulting in a limitation in improving the resolution. In addition, when irradiated with ultraviolet light to expose the ultraviolet light is transmitted through the support film affects the ultraviolet transmittance, there is a limit in implementing a high resolution by ultraviolet scattering by the particles inside the support film.

In order to solve this problem, the support film may be peeled off and then exposed, but the photoresist may be tacky, and the film may be attached to the photoresist when the support film is peeled off, resulting in damage to the photoresist. There is a problem that it is lowered, the mask is contaminated and the life of the mask is shortened.

Therefore, in reality, the exposure after peeling off the support film is difficult to be achieved, and thus the problem of resolution reduction remains.

Furthermore, as the density of printed circuit boards and semiconductor packaging technologies have increased, the density of circuit lines has been increased, so there is an urgent need for high resolution dry film photoresists applicable to such microcircuit boards.

The present invention improves the resolution by performing the exposure process in a state in which the support film is removed, and in particular, provides a multilayer film that does not damage the resin protective layer when the support film is removed while adhering the support film and the resin protective layer to an appropriate level. It is.

One embodiment of the present invention comprises laminating a support film, a release layer and a resin protective layer sequentially, the release layer comprises one or more selected from silicone resins, fluorine resins and aliphatic wax, the resin protective layer is A weight average molecular weight of 5000 to 300000 is a multi-layer film containing polyvinyl alcohol or polyethylene glycol.

Another embodiment of the present invention is a multilayer film having an adhesive force of 0.0005 to 0.01 N / cm between the release layer and the resin protective layer.

Another embodiment of the present invention is the resin protective layer is a multilayer film having a haze of 3.0% or less, and a developing time per 1 μm of 10 seconds or less.

Another embodiment of the present invention is a multilayer film in which the resin protective layer has a thickness of 10 μm or less.

Another embodiment of the present invention is the polyvinyl alcohol is a multilayer film having a saponification degree of 75 to 97%.

Another embodiment of the present invention is a multilayer film further comprising a protective film on one surface of the resin protective layer.

The multilayer film according to the present invention can be subjected to the exposure process with the support film removed, thereby ultimately improving the resolution by preventing adverse effects of the exposure effect by the support film.

In particular, when removing the support film while adhering the support film and the resin protective layer to an appropriate level, it is possible to prevent the fall of the haze without damaging the resin protective layer, and the development time does not decrease, thereby achieving high resolution. have.

FIG. 1A is an electron micrograph taken at 1200 times magnification of the surface of a printed circuit board after the development process manufactured by applying the multilayer film of Example 1. FIG.
FIG. 1B is an electron micrograph taken at 1200 times magnification of the surface of a printed circuit board after a developing process manufactured without applying the multilayer film of Comparative Example 1. FIG.
Figure 2a is an electron micrograph taken at a magnification of 1500 times the surface of the printed circuit board after the development process manufactured by applying the multilayer film of Example 4.
FIG. 2B is an electron micrograph taken at a magnification of 1500 times the surface of the printed circuit board after the developing process manufactured without applying the multilayer film of Comparative Example 2. FIG.
3A is an electron micrograph taken at 700 times the surface of a printed circuit board after the developing process manufactured by applying the multilayer film of Example 5. FIG.
3B is an electron micrograph taken at 700 times the surface of the printed circuit board after the developing process manufactured without applying the multilayer film of Comparative Example 3. FIG.

According to an embodiment of the present invention, the support film, a release layer and a resin protective layer are sequentially laminated, and the release layer includes at least one selected from a silicone resin, a fluorine resin, and an aliphatic wax, and the resin protection The layer is to provide a multilayer film comprising polyvinyl alcohol or polyethylene glycol having a weight average molecular weight of 5000 to 300000.

The multilayer film of the present invention has a structure of sequentially laminating a support film, a release layer and a resin protective layer.

Since the support film serves as a support of the resin protective layer, it is preferable to have sufficient mechanical properties. More specifically, the support film includes a polyester film such as polyethylene terephthalate film and polyethylene naphthalate film; Polyolefin-based films such as polyethylene films, and polypropylene films; Polyvinyl-based films such as copolymer films of polyvinylchloride and vinyl acetate, polytetrafluoroethylene films, and polytrifluoroethylene films; Polyimide film; Polyamide-based films such as 6,6-nylon; Polyacetate-based films such as cellulose triacetate film and cellulose diacetate film; Polyacrylate-based films such as alkyl poly (meth) acrylate films; Polyacrylic films such as (meth) acrylic acid ester copolymer films; These etc. are mentioned, Preferably, a polyethylene terephthalate is mentioned in consideration of mechanical properties and economics.

The thickness of the support film can be selected according to any purpose in the range of 10 to 100 μm.

The release layer is formed on the support film to bond the resin protective layer and the support film to an appropriate level, and at the same time serves to damage the surface of the resin protective layer when peeling off the support film from the resin protective layer.

Specifically, when the multilayer film is used in the pattern forming method, for example, a photoresist coated with a resin protective layer of a multilayer film having a support film and a resin protective layer laminated thereon is printed on a printed circuit board (PCB) substrate. After lamination to contact the support film, the support film is peeled off from the resin protective layer. In the case of a multilayer film in which a resin protective layer is laminated without a release layer on top of the support film, the support film is subjected to a step of removing the support film. There is a problem that the resin protective layer is not separated and the workability due to the process disruption is lowered, there is a problem that the multilayer film is produced in poor.

In addition, even if the support film and the resin protective layer are not separated before the support film is removed, the surface of the resin protective layer is damaged while the support film is peeled off, resulting in lower haze and adversely affect the development time. Problem occurs.

The release layer includes at least one selected from silicone resins, fluororesins and aliphatic waxes.

The release layer is required to have a release force at an appropriate level between the release layer and the resin protective layer in consideration of the case of removing the support film from the resin protective layer as described above, when the release film is removed from the resin protective layer The adhesive force between the release layer and the resin protective layer is preferably 0.0005 to 0.01 N / cm in that the layer should not damage the surface of the resin protective layer. In detail, when the adhesive force is within the range, when the lamination is a multilayer film further comprising a protective film on the resin protective layer, the protective film is removed to laminate the multilayer film on the photoresist formed on the PCB substrate. When the support film and the resin protective layer is not separated, there is an advantage that can be removed without damaging the surface of the resin protective layer when removing the support film before exposure.

The resin protective layer comprises polyvinyl alcohol or polyethylene glycol having a weight average molecular weight of 5000 to 300000, preferably 5000 to 150000, more preferably 5000 to 100000. When the weight average molecular weight is included in the above range, the coating on the film is well performed, the strength can be realized to a level capable of performing the protective function of the photoresist, and the development time of the appropriate level, after lamination on the PCB The problem which is damaged when peeling a support film can be prevented.

The resin protective layer has a haze of 3.0% or less and a developing time per micrometer of 10 seconds or less.

When the multilayer film according to the present invention is used in the pattern forming method, an example will be described. First, the resin protective layer of the multilayer film in which the support film and the resin protective layer are laminated is placed on the printed circuit board (CCL (copper flexible substrate)) substrate. Lamination is in contact with the coated photoresist. Then, the support film is removed, the mask of the desired pattern is applied on the resin protective layer, exposed by ultraviolet (UV) exposure, and the developing process of washing off the uncured portion using a suitable supernatant is performed. Rough

The developer is mostly composed of a water-soluble solvent. It is important that the resin protective layer is well dissolved in the water-soluble solvent of the developer so that the residue does not remain in the photoresist after development, and this is one of the factors that improve the developability.

In particular, the water-soluble polymer included in the resin protective layer may decrease the solubility of the water-soluble polymer as the weight average molecular weight increases, so that the degree of washing in the developer.

This developability is also affected by the development time. The faster the development time of the resin protective layer is, the better. However, when the development time of the resin protection layer is slower, the difference in development time due to the thickness deviation of the resin protection layer is generated. Since the adhesion may be reduced by washing more than necessary, or the resolution may be reduced by less washing, the development time of the resin protective layer should have an appropriate time considering the development of the photoresist for precise pattern formation.

Therefore, the resin protective layer includes a water-soluble polymer having an appropriate weight average molecular weight to improve developability, and has an appropriate level of development time so that no residue is left and no damage is caused to the cured portion of the photoresist. It is important.

On the other hand, as one of the methods for improving the resolution, it is important to form the pattern more precisely. In order to form a fine pattern, the light scattering degree to the resin protective layer during exposure should be low, so the haze value is required to be low. This is because light passes through the resin protective layer when the photoresist is exposed.

In the present invention, by including a resin protective layer having a haze of 3.0% or less, preferably 0.001 to 3.0%, and a developing time per micrometer of 10 seconds or less, preferably 0.1 to 10 seconds, the light transmittance at the time of exposure is increased and optimized With development time, the resolution can be improved.

Specifically, since the haze of the resin protective layer is required to have a low value in order to lower the light scattering degree, a lower limit value is preferable, and in the case of more than 3%, the shape of the photosensitive resin layer that has been exposed and developed ( The side wall is not smooth and rough.

In addition, the development time of the resin protective layer is required to have a low value in order to improve the developability, the lower the lower limit is preferable, the more the difference in the development time according to the thickness deviation of the resin protective layer when more than 10 seconds There is a problem that the photoresist is washed more than necessary to reduce the adhesion, or less washed to reduce the resolution.

In addition, the multilayer film of the present invention has a structure in which the resin protective layer and the support film are laminated, and the resin protective layer of the multilayer film is used in contact with the photoresist, and the exposure process is performed by removing the support film before the exposure process. Therefore, in the case of performing a general process using a conventional photoresist, the photoresist may be coated, dried or exposed to light, and the photoresist may be damaged due to contact with the mask during the exposure operation. Can be prevented.

The resin protective layer has a thickness of 10 μm or less, preferably 0.001 to 10 μm, more preferably 0.001 to 5 μm.

As described above, the light is applied to the mask during exposure, and the closer the distance between the mask and the photoresist is, the higher the resolution can be realized. For this purpose, it is best to expose the mask on top of the photoresist, but since it adheres to the mask due to the adhesion of the photoresist, not only the photoresist is damaged but also the mask is contaminated. there was.

The present invention is required to have a low thickness of the resin protective layer in order to implement a high resolution, so the lower the lower limit is preferable, and therefore, by using a resin protective layer having a thickness of 10㎛ or less, to minimize the separation distance with the mask In addition, damage to the photoresist and contamination of the mask do not occur even when the support film is removed and the exposure is performed, so that the limitations of the conventional resolution can be overcome, and high resolution can thus be realized.

It does not specifically limit as a method of forming such a resin protective layer, The composition for resin protective layer formation can be melt | dissolved in the solvent containing the organic solvent and water, and can be formed by apply | coating and drying on a mold release layer.

In particular, the polyvinyl alcohol according to the present invention preferably has a saponification degree of 75% to 97%. The degree of saponification is a factor that affects the developability. When the degree of saponification is within the above range, the resin protective layer has an appropriate developing time, and thus does not reduce the adhesion and the resolution during the pattern formation process by the photoresist. have.

Meanwhile, the composition of the photoresist may vary depending on whether it is applied in a negative or positive type. The composition of such negative type or positive type photoresist may be generally selected from photosensitive resin compositions well known in the art.

For example, when the photoresist is negative, the binder resin and the photopolymerizable compound may include an ethylenically unsaturated compound, a photopolymerization initiator, and an additive.

As the binder resin, an acrylic polymer, polyester, polyurethane, or the like may be used. Of these, methacrylic copolymer (methacrylic copolymer) which is a kind of acrylic polymer is preferable. Copolymers of ethylenically unsaturated carboxylic acids and other monomers can be used as desired. As the methacrylic copolymer, a methacrylic copolymer including an acetoacetyl group may also be used. Methacrylic monomers usable for synthesizing the methacrylic copolymers include methyl methacrylate, methyl methacrylate, propyl methacrylate and butyl methacrylate. Butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, Dimethylaminoethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, and the like. have. As the ethylenically unsaturated carboxylic acid, monoacrylic acid (monoacrylic acid) such as acrylic acid, methacrylic acid, and crotonic acid is used. In addition, 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 preferable. Other copolymerizable monomers include acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, styrene, a-methylstyrene, Vinyl acetate, alkyl vinyl ether, and the like.

As the photopolymerizable monomer, an ethylenically unsaturated compound may be a monofunctional, bifunctional, trifunctional or higher polyfunctional monomer. The polyfunctional monomers include ethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and propylene glycol dimethacrylate. (propylene glycol dimethacrylate), polypropylene glycol dimethacrylate, butylene glycol dimethacrylate, butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexane 1,6-hexane glycoldimethacrylate, trimethylolpropane trimethacrylate, glycerin dimethacrylate, pentaerythritol dimethacrylate, penta Erythritol trimethacrylate (pentaerythritol trimethacrylate), Dipentaerythritol pentamethacrylate (dipentaerythritolpentamethacrylate), 2,2-bis (4-methacryloxydiethoxyphenyl) propane (2,2-bis (4-methacryloxydiethoxyphenyl) propane), 2-hydroxy-3-meta 2-hydroxy-3-methacryloyloxypropyl methacrylate, ethylene glycol diglycidylether dimethacrylate, diethylene glycol diglycidyl ether dimethacrylate (2-hydroxy-3-methacryloyloxypropyl methacrylate) diethylene glycol diglycidyl ether dimethacrylate, phthalic acid diglycidyl ester dimethacrylate, glycerine polyglycidyl ether polymethacrylate, and the like. The monofunctional monomers include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, and 2-hydroxybutyl methacrylate. 2-phenoxy-2-hydroxypropyl methacrylate, 2-methacryloyloxy-2 hydroxypropyl phthalate, 3 3-chloro-2-hydroxypropyl methacrylate, glycerin monomethacrylate, 2-methacryloyloxyethyl acid phosphate, Methacrylic acid of phthalic acid derivatives, N-methylol methacrylamide, and the like can be used. The monofunctional monomer may be used together with the multifunctional monomer.

Examples of the photopolymerization initiator 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 (3,3-dimethyl-4-methoxybenzophenone), benzophenone, p, p'-bis (dimethylamino) benzophenone (p, p'-bis (dimethylamino) benzophenone), p, p'-bis (diethylamino) benzophenone (p, p'-bis (diethylamino) benzophenone), p, p'-diethylaminobenzophenone (p, p'-diethylaminobenzophenone), pivalon ethyl ether ( pivalone ethyl ether), 1,1-dichloroacetophenone, pt-butyldichloroacetophenone, hexaaryl- Dimer of hexaaryl-imidazole, 2,2'-diethoxyacetophenone, 2,2'-diethoxy-2-phenylacetophenone (2,2'-diethoxy -2-phenylacetophenone), 2,2'-dichloro-4-phenoxyacetophenone, phenyl glyoxylate, a-hydroxy-isobutylphenone (2,2'-dichloro-4-phenoxyacetophenone) a-hydroxyisobutylphenone), dibenzospan, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl-1-propanone (1- (4-

isopropylphenyl) -2-hydroxy-2-methyl-1-propanone), 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone (2-methyl- [4- (methylthio ) phenyl] -2-morpholino-1-propanone), tri-bromophenylsulfone, tribromomethylphenylsulfone, and the like can be used.

As the additive, a softening agent such as vinyl chloride resin may be included. Specific examples of the phthalic ester include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, and dioctyl phthalate. phthalate, diisodecyl phthalate, butylbenzyl phthalate, diisononyl phthalate, ethylphthalyl ethyl glycolate, dimethyl isophthalate, dimethylisophthalate, dichlorohexyl phthalate dichlorohexyl phthalate, and esters of fatty acids or arimatic acid, such as dioctyl adipate, diisobutyl adipate, dibutyl adipate, Diisodecyl adipate, dibutyl diglycodiate l

adipate), dibutyl sebacate, dioctyl sebacate, and the like. In the present invention, glycerol triacetate, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tributyl phosphate, trioctylphosphate, tributoxyethyl phosphate phosphate, tris-chloroethylphosphate, tris-dichloropropyl phosphate, triphenylphosphate, tricresyl phosphate, trixylenyl phosphate ), Cresyl diphenyl phosphate, octyl diphenyl phosphate, xylenyl diphenyl phosphate, trilauryl phosphate, tricetyl phosphate , Tristearyl phosphate phosphate, trioleyl phosphate, triphenyl phosphite, tris-tridecyl phosphite, dibutyl hydrogen phosphite, dibutyl-butyl phosphate Dibutyl-butyl phosphonate, di (2-ethylhexyl) 2-ethylhexyl phosphonate, 2-ethylhexyl-2-ethylhexyl phosphonate (2-ethylhexyl-2 -ethylhexylphosphonate, methyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, dibutyl acid phosphate, monobutyl acid phosphate ), Octyl acid phosphate, dioctyl phosphate, isodecyl acid phosphate, monoisodecyl phosphate, decanoic acid phosphate It may also be used, such as softeners (decanol acid phosphate).

In addition, volatile organic compounds such as glycerin, trimethylolpropane, ethylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol (dipropylene glycol) or lower alkyl ethers thereof, lower fatty acid esters, higher fatty acids or their esters, higher fatty alcohols or esters thereof, and the like can also be used as the softening agent of the present invention.

The binder resin, the photopolymerizable compound, the photoinitiator, and the additive contained in the negative photoresist resin composition described above can be appropriately mixed and used according to any purpose.

On the other hand, when the photoresist is positive, it may include an alkali-soluble resin and a diazide-based photosensitive compound, specifically, a novolak resin may be used as the alkali-soluble resin, and more preferably, a cresol novolak resin may be included. . The novolak resin can be obtained by polycondensation of phenol alone or a combination of an aldehyde and an acid catalyst.

The phenols are not particularly limited, and phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,5-xylenol, 3,4-xylenol, 3, 5-xylenol, 2,3,5-trimethylphenol-xylenol, 4-t-butylphenol, 2-t-butylphenol, 3-t-butylphenol, 4-methyl-2-t-butylphenol Monovalent phenols; And 2-naphthol, 1,3-dihydroxy naphthalene, 1,7-dihydroxy naphthalene, 1,5-dihydroxy naphthalene, resorcinol, pyrocatechol, hydroquinone, bisphenol A, fluoroglucinol, Polyhydric phenols, such as a pyrogallol, etc. are mentioned, These can be selected individually and can be used in combination of 2 or more types. In particular, a combination of m-cresol and p-cresol is preferable.

Examples of the aldehydes include, but are not particularly limited to, formaldehyde, trioxane, paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde, alpha or beta-phenyl propylaldehyde, o-, m- or p-hydride. Roxy benzaldehyde, glutaraldehyde, terephthalaldehyde, etc. are mentioned, It can be used individually or in combination of 2 or more types.

The cresol novolak resin preferably has a weight average molecular weight (based on the GPC method) of 2,000 to 30,000, and the cresol novolak resin has different physical properties such as photosensitivity and residual film ratio depending on the content ratio of meta / para cresol. As such, it may be desirable that the meta / para cresol content is mixed in a ratio of 4: 6 to 6: 4 by weight. When the content of the meta cresol in the cresol novolak resin exceeds the above range, the photoresist rate is increased while the residual film rate is drastically lowered. When the content of the para cresol exceeds the above range, the photosensitivity is slowed. The cresol novolac resin may be used solely a cresol novolac resin having a meta / para cresol content of 4: 6 to 6: 4 by weight, and more preferably, different resins may be mixed. In this case, it is preferable to use the cresol novolak resin in a ratio of cresol novolac resin having a weight average molecular weight of 8,000 to 30,000 and a novolak resin 7: 3 to 9: 1 having a weight average molecular weight of 2,000 to 8,000. .

Above and below "weight average molecular weight" is defined in terms of polystyrene equivalents, as determined by gel permeation chromatography (GPC) unless otherwise specified.

In the composition of the photoresist layer, the diazide-based photosensitive compound acts as a dissolution inhibitor to reduce the solubility of alkali-soluble resin in alkali, and when irradiated with light, the diazide-based photosensitive compound is converted into alkali-soluble material to increase alkali solubility of alkali-soluble resin. do. As such, due to the change in solubility due to light irradiation, the exposed portion of the film type photodegradable transfer material of the present invention is developed.

The diazide photosensitive compound can be synthesized by esterification of a polyhydroxy compound and a quinone diazide sulfonic acid compound. The esterification reaction for obtaining a diazide photosensitive compound is carried out by dioxane, acetone, tetrahydrofuran, methyl ethyl ketone, N-methylpyrrolidone, chloroform, triethylamine, N, and polyhydroxy compound and quinone diazide sulfonic acid compound. A basic catalyst such as -methylmorpholine, N-methylpiperazine or 4-dimethylaminopyridine can be added dropwise and condensed, and then the obtained product can be washed, purified and dried.

The quinone diazide sulfonic acid compound is, for example, 1,2-benzoquinone diazide-4-sulfonic acid, 1,2-naphthoquinone diazide-4-sulfonic acid, 1,2-benzoquinone diazide-5-sulfonic acid and O-quinone diazide sulfonic acid compounds such as 1,2-naphthoquinone diazide-5-sulfone phase, other quinone diazide sulfonic acid derivatives, and the like. The quinonediazide sulfonic acid compound itself has a function as a dissolution inhibiting agent that lowers the solubility of alkali-soluble resin in alkali. However, it is decomposed to be alkali-soluble at the time of exposure and thereby rather has the property of promoting dissolution of alkali-soluble resin in alkali.

Examples of the polyhydroxy compound include trihydroxy benzophene such as 2,3,4-trihydroxy benzophenone, 2,2 ', 3-trihydroxy benzophenone, and 2,3,4'-trihydroxy benzophenone. Rice field; Tetrahydroxy benzophene such as 2,3,4,4'-tetrahydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxy benzophenone, and 2,3,4,5-tetrahydroxybenzophenone Rice field; 2,2 ', 3,4,4'-pentahydroxy benzophenone, 2,2', 3,4,5-pentahydroxy benzophenone pentahydroxy benzophenone; Hexahydroxy benzophenones such as 2,3,3 ', 4,4', 5'-hexahydroxybenzophenone and 2,2 ', 3,3', 4,5'-hexahydroxy benzophenone; Gallic acid alkyl esters; Oxyflavones etc. are mentioned.

Specific examples of the diazide photosensitive compound obtained from these include 2,3,4,4'-tetrahydroxybenzophenone-1,2-naphthoquinone diazide-5-sulfonate, 2,3,4-tri Hydroxybenzophenone-1,2-naphthoquinonediazide-5-sulfonate and (1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxy Phenyl) ethyl] benzene) 1, 2- naphthoquinone diazide-5-sulfonate 1 or more types chosen are mentioned.

The diazide-based photosensitive compound may be advantageously 30 to 80 parts by weight based on 100 parts by weight of the alkali-soluble resin in the photoresist layer composition in view of developability or solubility.

The positive type photoresist resin composition described above may include a sensitivity enhancer, which is intended to improve sensitivity. Examples thereof include 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone and 1- [1- (4-hydroxyphenyl) isopropyl] -4- [ 1,1-bis (4-hydroxyphenyl) ethyl] benzene. When the sensitivity enhancer is included in an amount of 3 to 15 parts by weight based on 100 parts by weight of the alkali-soluble resin, it may be advantageous in terms of improving the photosensitive effect and margin of the window process.

In addition, the positive photoresist may include other components or additives such as leveling agents, fillers, antioxidants, and the like.

On the other hand, a composition containing an alkali-soluble resin, a diazide-based photosensitive compound, etc. is dispersed in a predetermined amount of a solvent to be prepared and then applied. At this time, examples of the solvent include ethyl acetate, butyl acetate, ethylene glycol monoethyl ether acetate, and diethylene. Glycol monoethyl ether acetate, propylene glycol monoethyl ether acetate, acetone, methyl ethyl ketone, ethyl alcohol, methyl alcohol, propyl alcohol, isopropyl alcohol, benzene, toluene, cyclopentanone, cyclohexanone, ethylene glycol, xylene, ethylene And at least one selected from the group consisting of glycol monoethyl ether and diethylene glycol monoethyl ether.

Multilayer film according to another embodiment of the present invention may further include a protective film on one surface of the resin protective layer. The protective film serves to protect the resin protective layer from the outside, and when the multilayer film is applied to a later process, it is easily detached, and requires proper release property and adhesion so as not to be released during storage and distribution.

As described above, the multilayer film according to the present invention can be suitably applied to the pattern forming process of the photoresist coated on the PCB substrate, and in addition, the surface and the process that cannot use the contact type exposure due to the adhesion of the photoresist should be protected. Applicable to the process.

When the multilayer film according to the present invention is applied to a process to protect the surface, it is possible to obtain an effect of preventing physical damage when removing the surface protective layer.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described. However, the following embodiments are merely preferred embodiments of the present invention, and the present invention is not limited to the following embodiments.

Example  1 to 5 and Comparative example  1 to 3

≪ Example 1 >

(a) 20 g of polyvinyl alcohol (KURARAY, PVA205) having a weight average molecular weight of 22000, saponification degree of 87%, and 0.1 g of polysilicon were dissolved in 100 g of butoxyethanol for 6 hours under the condition of 80 ° C. When the particle size of 0㎛ polysilicon (BYK, BYK-349, 0.25% of the solid content after drying) 0.05g was added to 100g of distilled water and stirred for 6 hours at 80 ℃ completely to prepare a composition for the resin protective layer. This was coated on a support film having a thickness of 16 μm (haze 2.3%, no surface treatment, polyethylene terephthalate film, FDFR-16 μm, KOLON) using a coating bar, and then dried at 80 ° C. for 10 minutes using a hot air oven to obtain a thickness. The resin protective layer of 3 micrometers was formed. In this case, when the polysilicon is dissolved in the solvent, the particle size of 0 μm means that the polysilicon is almost completely dissolved in the solvent under the condition of 80 ° C. for 6 hours, and thus no particulate was found. Unless otherwise specified, 'particle size 0 μm' means the same meaning as described above.

This was coated on a support film (CY201-16 μm, KOLON) having a thickness of 16 μm using a coating bar, and then dried at 80 ° C. for 10 minutes using a hot air oven to form a resin protective layer having a thickness of 3 μm. In this case, the support film is a polyethylene terephthalate film in which a release layer is formed by using a silicone resin on one surface of the support film by an in-line coating (ILC) method. For reference, the release layer on the support film may be formed by an off-line coating method in addition to the ILC method. The ILC method and the off-line coating method are well known in the art to which the present invention pertains, and a detailed description thereof will be omitted.

(b) A photoresist was prepared in the composition and content used for the ND088 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(c) The photoresist resin composition was spin-coated on top of the CCL (copper flexible substrate), and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 10 μm.

(d) Lamination was carried out at 50 ° C. at a pressure of 4 kgf / cm 2 such that the photoresist of (c), which had been dried, and the resin protective layer of (a) were in contact with each other.

<Example 2>

It carried out by the same method as Example 1 except having performed as follows.

(a) 10 g of polyvinyl alcohol (KURARAY, PVA217) having a weight average molecular weight of 75000, saponification degree of 87%, and polysilicon having a particle size of 0 µm (BYK, BYK-349, 0.25% of solid content after drying) 0.025 g was added to 100 g of distilled water and stirred at 80 ° C. for 6 hours to completely dissolve to prepare a resin protective layer composition. This was coated on a 16 μm thick support film (CY201-16 μm, KOLON) using a coating bar, and then dried at 80 ° C. for 10 minutes using a hot air oven to form a resin protective layer having a thickness of 3 μm.

<Example 3>

It carried out by the same method as Example 1 except having performed as follows.

(a) 10 g of polyethylene glycol (manufacturer: Sigma-Aldrich, weight average molecular weight 20,000), and 0.025 g of polysilicon having a particle size of 0 μm (BYK, BYK-349, 0.25% of the solid content after drying) were added to 100 g of distilled water. After stirring for 6 hours at ℃, it was completely dissolved to prepare a composition for a resin protective layer. This was coated on a support film (CY201-16 μm, KOLON) having a thickness of 16 μm using a coating bar, and then dried at 80 ° C. for 20 minutes using a hot air oven to form a resin protective layer having a thickness of 3 μm.

<Example 4>

It carried out by the same method as Example 1 except having performed as follows.

(b) A photoresist was prepared in the composition and content used for LD090 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(c) The photoresist resin composition was spin coated on the CCL (copper flexible substrate), and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 15 μm.

Example 5

It carried out by the same method as Example 1 except having performed as follows.

(b) Photoresist was prepared in the composition and content used in PD092 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(c) The photoresist resin composition was spin coated on the CCL (copper flexible substrate), and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 20 μm.

Comparative Example 1

(a) A photoresist was prepared in the composition and content used for the ND088 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(b) The photoresist resin composition was spin coated on the CCL (copper flexible substrate) and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 10 μm.

Comparative Example 2

(a) Photoresist was prepared in the composition and content used for LD090 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(b) The photoresist resin composition was spin coated on the CCL (copper flexible substrate) and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 15 μm.

Comparative Example 3

(a) Photoresist was prepared in the composition and content used in PD090 series (Kolon). Specifically, the photoinitiator was dissolved in methyl ethyl ketone and methyl alcohol as a solvent, and then photopolymerizable oligomer and binder polymer were added and mixed for 1 hour using a mechanical stirrer to prepare a photoresist resin composition. .

(b) The photoresist resin composition was spin coated on the CCL (copper flexible substrate), and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photoresist having a thickness of 20 μm.

The weight average molecular weight and saponification degree of polyvinyl alcohol of polyvinyl alcohol or polyethylene glycol which are water-soluble polymers according to Examples 1 to 5 were measured by the following method.

Weight average molecular weight measurement

The weight average molecular weight of the water-soluble polymer is 40 ° C using GFC (Gel Filtration Chromatography; Varian GPC system), Stationary Phase is (Plgel Mixed D) × 2, Mobile Phase: THF, 1.0ml / min, Injection: 100µl , Detection: The standard was measured by dissolving PS Standard (Polymer Standards Service, Mp 723000,219000,89300,52200,30300,7000,5000,2960) in THF at the concentration of 0.1% under the conditions of RI and 40C. . The sample was dissolved in THF at a concentration of 0.2% and filtered with a 0.45 μm PTFE syringe filter.

Safflower  Measure

The saponification degree of polyvinyl alcohol was measured in accordance with JIS K6726 method.

The adhesion of the multilayer film prepared according to Examples 1 to 5 was measured as follows.

Adhesive force measurement

<Adhesion between resin protective layer and PET>

In the case of Examples 1 to 5, the support film was peeled off, and then laminated on a resin protective layer so as to contact a PET film (FDFR, manufactured by Kolon) having a thickness of 20 cm and a thickness of 19 μm. Lamination was carried out so as to contact a PET film (FDFR, manufactured by Kolon) having a thickness of 19 cm with a width of 3 cm and a length of 20 cm. After releasing the PET film was measured using a universal testing machine (UTM, 4303 series, Instron Co., Ltd.) to release the mold using a 10N load cell at a speed of 100mm / min from the starting point 5cm to 8cm point. The conditions for lamination of the PET film used are the same as the conditions for bonding with the mask during normal exposure.

<Adhesion between release layer and resin protective layer>

The substrate on which the support film, the release layer, the resin protective layer, and the photoresist prepared according to Examples 1 to 5 were laminated was made into a rectangular specimen having a width of 3 cm and a length of 20 cm, and the support film of the substrate was released at 5 starting points. The force required to release using a 10N load cell at a speed of 100 mm / min from the cm point to the 8 cm point was measured using UTM (4303 series, Instron).

Table 1 shows the results of measuring the adhesive strength of the substrates prepared in Examples 1 to 5 and Comparative Examples 1 to 3.

Adhesion (N / cm) Adhesive force between resin protective layer and PET film Adhesive force between the release layer and the resin protective layer Example One 0.0010 0.0027 2 0.0009 0.0031 3 0.0027 0.0028 4 0.0010 0.0028 5 0.0010 0.0027 Comparative example One 0.0047 ^* - 2 0.0058 ^* - 3 0.0054 ^* -

(Note) The exceptional * in Table 1 means the adhesive force between the support film and the photoresist.

As a result of the measurement, Comparative Examples 1 to 3 are in the range of inhibiting workability due to the high adhesion between the photoresist and PET film, but in Examples 1 to 5, the adhesive force between the support film and the resin protective layer is in the range of workability. In addition, since the resin protective layer is present on the photoresist, the adhesive force with the PET film is reduced, it can be seen that the range does not impair workability.

Thus, in Examples 1 to 5, it can be seen that the adhesive force between the resin protective layer and the mask material generally used in the exposure conditions is very low, and thus the handling is easy during exposure.

Property evaluation

Thereafter, the substrates prepared in Examples 1 to 5 and the substrates prepared in Comparative Examples 1 to 3 were evaluated in the following manner.

(1) formation of a circuit

Exposure was performed by irradiating with a UV exposure machine (Perkin Elmer OB-7120, 5KW parallel light). After the exposure, the printed circuit board was developed by passing through a developer.

In this case, in the case of Examples 1 to 5 including the resin protective layer, the support film was peeled off before the exposure step, and Comparative Examples 1 to 3 were carried out under the same conditions without the pre-exposure step.

(a) Development time

A fan-type CCL substrate spraying a developing solution (1% Na ₂ CO ₃ aqueous solution) at a pressure of 1.5 kgf / cm 2 at a temperature of 30 ° C. was prepared without using a multilayer film as in Comparative Examples 1 to 3. The distance between the nozzle and the substrate was passed through a developer having a 15 cm to measure the time for removing the photoresist by completely washing it in the developer, which is called the minimum development time of the photoresist (hereinafter, referred to as 'S _min '). In addition, the actual development time of the photoresist alone (hereinafter referred to as 'S _del ') was calculated to be twice the minimum development time S _min of the photoresist only.

On the other hand, in the case of using a multilayer film, the minimum development time (hereinafter referred to as 'P _min ') of the film including the resin protective layer is a pressure on the CCL substrate formed in Examples 1 to 5 under the conditions of temperature 30 ℃ The resin protective layer and the photoresist were completely washed by the developer by passing through a developer having a fan of 15 cm between the nozzle and the substrate, which sprays the developer (1% Na ₂ CO ₃ aqueous solution) at 1.5 kgf / cm _2. It measured the removal time, the actual processing time of the film made of a resin protective layer (hereinafter referred to as 'P _del' as hereinafter), the developing time of the resin protection layer only on the actual developing time (S _del) in only the photo resist (hereinafter, 'P _tim ') should be added.

The development time of only the photoresists of Examples 1 to 5 can be used interchangeably because the photoresist used in Examples 1 to 3 and the photoresist of Comparative Example 1 are the same, and Example 4 is Comparative Example 2 and Example. 5 can be used as Comparative Example 3.

<Equation 1>

P _del = S _del + P _tim

= S _min × 2 + P _tim

Another expression of Equation 1 is expressed by Equation 2 below.

<Formula 2>

P _del = P _min + S _min

Therefore, the minimum development time when the multilayer film is used and the minimum development time when the multilayer film is not used, that is, the minimum development time of the photoresist alone, are measured, respectively. The time can be calculated.

Here, the minimum development time S _min of the photoresist is divided by the minimum development time for Comparative Example 1.

The developing time P _tim of only the resin protective layer is calculated from Equations 1 and 2, and the value obtained by dividing the calculated developing time by the thickness of the resin protective layer is defined as the developing time per μm of the resin protective layer.

(b) sensitivity and exposure dose

In the case of exposure, Examples 1 to 3 placed a sensitivity (21-stage Stouffer Step Tablet) on the resin protective layer on the resin protective layer, and in the case of Comparative Example 1, the sensitivity 6, 7, and 8 The exposure amount to obtain was measured using a photometer (UV-351, manufactured by ORC), and the values are shown in Table 2 below. At this time, the sensitivity was evaluated by the maximum number of units of the photosensitive resist remaining on the substrate after development.

(2) Circuit Properties: Resolution, Session Adhesion, 1/1 (Line / Space) Resolution

The Kolon Test Artwork was used to evaluate the circuit properties by measuring the resolution, thin line adhesion, and 1/1 (Line / Space) resolution.

In this experiment, the resolution is a measure of how small the line width is developed when the unexposed areas are developed. The smaller the value, the higher the resolution. The mask used for measuring the measured resolution is 0.5 μm up to 4 to 30 μm. The mask was formed at intervals of and a mask made with an interval of 400 μm was used for the resolution of the value to be implemented. The thin line adhesion value is a measure of how small the line width after exposure is formed to form a straight line circuit without being eroded. The smaller the value, the better the fine line adhesion value, and the mask used for measuring the measured thin line adhesion value. Was formed at intervals of 0.5 μm to 4 to 30 μm, and a mask made of 400 μm was used as a thin wire adhesion value of the value to be implemented. In addition, 1/1 resolution represents the value of the cleanest developed minimum line width with the distance between the circuit line and the circuit line 1: 1.

(3) surface analysis

Figure 1a is a photograph taken on the surface of the printed circuit board prepared by applying the multilayer film of Example 1 after the exposure and development process as described above with an electron microscope, Figure 1b is applied to the multilayer film of Comparative Example 1 This is a photograph of a printed circuit board manufactured without using the same.

Figure 2a is a photograph taken after the exposure and development process of the printed circuit board prepared by applying the multilayer film of Example 4 as described above with an electron microscope, Figure 2b is applied to the multilayer film of Comparative Example 2 This is a photograph taken of a printed circuit board manufactured by the same method.

3A is a photograph taken after the exposure and development processes of the printed circuit board manufactured by applying the multilayer film of Example 5, as described above, using an electron microscope, and FIG. 3B illustrates the multilayer film of Comparative Example 3. This is a photograph taken of a printed circuit board manufactured by the same method.

Table 2 shows the measurement results of the circuit properties according to the development time and exposure conditions, respectively.

Developing time Exposure conditions Circuit properties Development time per 1㎛ (sec) Minimum developing time (sec) Actual development time (sec) Exposure
Energy (mJ / ㎠) Sensitivity (sst
/ 21sst) resolution
(Μm) Thin line
Adhesion
(Μm) 1/1
resolution
(Μm) Example 1 One 18 33 35 6 8 9 9 50 7 10 6 9 70 8 12 5 11 Example 2 2 21 36 35 6 7 9 9 50 7 10 6 10 70 8 12 5 11 Example 3 0.7 17 32 35 6 8 9 9 50 7 9 6 9 70 8 12 5 11 Example 4 One 26 49 5 6 14 18 17 7 7 18 14 18 10 8 24 12 21 Example 5 One 34 65 100 6 11 12 11 140 7 15 9 14 200 8 18 7 17 Comparative Example 1 - 15 ^* 30 ^** 33 6 8 9 9 51 7 10 6 9 70 8 12 5 11 Comparative Example 2 - 23 ^* 46 ^** 5 6 14 18 17 7 7 18 14 18 10 8 24 12 21 Comparative Example 3 - 31 ^* 62 ^** 102 6 11 12 11 139 7 15 9 14 200 8 18 7 17

Note: In Table 2, the minimum development time (sec) means the minimum development time (P _min ) of the film including the resin protective layer, and the actual development time (sec) is the actual development of the film including the resin protective layer. It means time P _del . However, * indicates the minimum development time (S _min ) of the photoresist only, ** refers to the actual development time (S _del ) of the photoresist only.

As a result of the measurement, the amount of exposure required to implement the same number of stages was almost no difference between Examples 1 to 3 and Comparative Examples 1 and 4, and Comparative Example 2, Example 5 and Comparative Example 3, It can be seen that the case of Example and the case of Comparative Example are almost similar. In addition, in Table 2, Comparative Examples 1 to 3 exhibited the same level of circuit physical properties as Examples 1 to 5, but the adhesion of Comparative Examples 1 to 3 in Table 1 was not good, as in Examples 1 to 5 It turned out that exposure can not be used.

In addition, as a result of the surface observation through the electron micrograph of FIGS. It can be seen that very good pattern and excellent circuit properties.

In conclusion, in the case of applying the multilayer film of the present invention, there is almost no unevenness, which is an advantage of not using the multilayer film, and has a very excellent pattern and excellent circuit properties, but does not impair workability in terms of adhesion with PET. In addition to easy handling during exposure, it is possible to prevent scratches of the photoresist and reduce the defects caused by foreign substances.

All simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (6)

It includes laminating a support film, a release layer and a resin protective layer sequentially,
The release layer includes at least one selected from a silicone resin, a fluorine resin, and an aliphatic wax, and the resin protective layer includes a polyvinyl alcohol or polyethylene glycol having a weight average molecular weight of 5000 to 300000. The multilayer film of claim 1, wherein the adhesive force between the release layer and the resin protective layer is 0.0005 to 0.01 N / cm. The multilayer film of claim 1, wherein the resin protective layer has a haze of 3.0% or less and a developing time per μm of 10 seconds or less. The multilayer film of claim 1, wherein the resin protective layer has a thickness of 10 μm or less. The multilayer film of claim 1, wherein the polyvinyl alcohol has a saponification degree of 75 to 97%. The multilayer film of claim 1, further comprising a protective film on one surface of the resin protective layer.

Images