KR102034200B1

KR102034200B1 - Method for manufacturing insulating film and multilayered printed circuit board

Info

Publication number: KR102034200B1
Application number: KR1020150153041A
Authority: KR
Inventors: 정우재; 경유진; 최병주; 최보윤; 이광주
Original assignee: 주식회사 엘지화학
Priority date: 2015-11-02
Filing date: 2015-11-02
Publication date: 2019-10-18
Also published as: KR20170050913A

Abstract

The present invention can realize a uniform and fine pattern while improving efficiency in terms of cost and productivity, and a multilayer printed circuit using an insulating layer manufacturing method and an insulating layer obtained from the insulating layer manufacturing method, which can secure excellent mechanical properties. It relates to a substrate manufacturing method.

Description

Insulation layer manufacturing method and multilayer printed circuit board manufacturing method {METHOD FOR MANUFACTURING INSULATING FILM AND MULTILAYERED PRINTED CIRCUIT BOARD}

The present invention relates to a method for manufacturing an insulating layer and a method for manufacturing a multilayer printed circuit board. More specifically, it is possible to realize a uniform and fine pattern while improving efficiency in terms of cost and productivity, and multilayer printing using an insulating layer manufacturing method capable of securing excellent mechanical properties and an insulating layer obtained from the insulating layer manufacturing method. It relates to a circuit board manufacturing method.

Recently, electronic devices have become smaller, lighter and more functional. To this end, as the application field of build-up printed circuit boards (PCBs) is rapidly expanding around small devices, the use of multilayer printed circuit boards is rapidly increasing.

Multi-layer printed circuit boards can be made from planar wiring to three-dimensional wiring. Especially in the industrial electronics field, the integration of functional devices such as integrated circuit (IC) and large scale integration (LSI) is improved, along with the miniaturization, light weight, high functionality, and structure of electronic devices. It is an advantageous product for electrical function integration, assembly time reduction and cost reduction.

Build-up PCBs used in these application areas must form via holes for connection between layers. Via holes, which correspond to interlayer electrical connection passages of multilayer printed circuit boards, are conventionally used as mechanical drills. However, due to the miniaturization of the circuit, the diameter of the hole decreases, and the machining method using the laser appears to be an alternative due to the increase in the machining cost and the limitation of the microhole processing.

However, in the case of a laser processing method, a CO 2 or YAG laser drill is used, but since the size of the via hole is determined by the laser drill, for example, in the case of a CO 2 laser drill, a via hole having a diameter of 50 μm or less is used. There is a limit that is difficult to manufacture. In addition, in the case where a large number of via holes are to be formed, there is a large cost burden.

Thus, in place of the above laser processing technology, a method of forming a via hole having a fine diameter at low cost using a photosensitive insulating material has been proposed. Specifically, the photosensitive insulating material may be a photosensitive insulating film called a solder resist capable of forming a fine opening pattern using photosensitive properties.

Such a photosensitive insulating material or solder resist may be divided into a case where a developer different from that of using a sodium carbonate developer for pattern formation is used. In the case of using other developers, photosensitive insulating materials or solder resists are difficult to apply in actual processes due to environmental and cost reasons.

On the other hand, the use of sodium carbonate developer has an environmentally friendly advantage. In this case, acid-modified acrylate resins including a plurality of carboxylic acids and acrylate groups are used to impart photosensitivity. Since most acrylate groups and carboxyl groups are linked by ester bonds, polymerization inhibitors or the like are used to polymerize to a desired shape. It will include, in order to cause a radical reaction by ultraviolet irradiation will also include a photoinitiator and the like.

However, the polymerization inhibitor or photoinitiator may diffuse out of the resin under high temperature conditions, causing interfacial desorption with the insulating layer or the conductive layer during or after the semiconductor package process. In addition, the ester bond in the resin causes a hydrolysis reaction at high humidity and decreases the crosslinking density of the resin, thereby increasing the moisture absorption rate of the resin. When the moisture absorption rate is high, the polymerization inhibitor or the photoinitiator may be used at high temperature. After the conversion to the resin out of the resin during or during the semiconductor package process, the interface layer desorption can occur with the insulating layer or the conductive layer, there is a limit that the reliability is reduced, such as deterioration of the HAST characteristics.

Accordingly, it is required to develop an insulating layer manufacturing method capable of realizing uniform and fine patterns at low cost while ensuring excellent reliability.

The present invention is to provide a method for producing an insulating layer that can implement a uniform and fine pattern, while improving the efficiency in terms of cost and productivity, and can secure excellent mechanical properties.

In addition, the present invention is to provide a method for manufacturing a multilayer printed circuit board using the insulating layer obtained from the insulating layer manufacturing method.

In the present specification, forming a patterned protective layer on a multilayer structure comprising at least two or more metal layers formed on a polymer resin layer comprising an alkali-soluble resin and a thermosetting binder; Etching the metal layer with the patterned protective layer to form a patterned metal layer; Alkali developing in a state in which a polymer resin layer is blocked with the patterned metal layer; And thermally curing the polymer resin layer.

Also provided herein is a method of manufacturing a multilayer printed circuit board comprising forming a patterned metal substrate on the insulating layer.

Hereinafter, an insulating layer manufacturing method and a multilayer printed circuit board manufacturing method according to a specific embodiment of the present invention will be described in detail.

According to one embodiment of the invention, forming a patterned protective layer on a multilayer structure comprising at least two or more metal layers formed on the polymer resin layer comprising an alkali-soluble resin and a thermosetting binder; Etching the metal layer with the patterned protective layer to form a patterned metal layer; Alkali developing in a state in which a polymer resin layer is blocked with the patterned metal layer; And thermosetting the polymer resin layer. A method of manufacturing an insulating layer may be provided.

The present inventors, according to the method of manufacturing the insulating layer of the embodiment, by using the fact that at least two or more metal layers formed on the polymer resin layer, for example, the first metal layer and the second metal layer can be selectively etched with each other, It was confirmed that fine pattern formation is possible through sequential etching.

In particular, the patterned protective layer formed on the at least two metal layers serves as a mask for blocking the etching liquid, so that the metal layer portion exposed by the patterned protective layer is removed through etching and is applied to the patterned protective layer. It was confirmed that the metal layer portion not exposed by the protection was protected from the etching liquid.

In addition, sequential etching may be performed between the at least two metal layers. For example, a second metal layer located above the at least two metal layers may be patterned first, and the patterned second metal layer serves as a mask for blocking the lower metal layer, for example, the first metal layer, from the etching solution. Thus, the first metal layer portion exposed by the patterned second metal layer is removed by etching, and the first metal layer portion not exposed by the patterned second metal layer is left as it is protected from the etching solution. You can implement patterns.

Then, the patterned metal layer formed on the polymer resin layer having alkali solubility serves as a mask of the alkali developer, so that the portion of the polymer resin layer exposed by the metal layer pattern is removed through an alkali phenomenon, and is exposed by the metal layer pattern. The portion of the polymer resin layer not yet protected was protected from the alkaline developer, and it was confirmed that more uniform and fine patterns can be formed quickly and at low cost as compared with the conventional laser processing process.

In particular, the first metal layer formed on the polymer resin layer has a very thin thickness, and when the polymer resin layer is developed by using the first metal layer pattern to form a polymer resin pattern, the aspect ratio of the pattern is affected. It will not receive, it can form a fine and uniform pattern.

Furthermore, since the pattern forming process, the alkali developing process or the etching process through the photosensitive characteristic can be mass-produced quickly and at a relatively low cost, compared to the laser process, the efficiency of the process can be improved.

In addition, since the first metal layer pattern remains on the final manufactured insulating layer, it is possible to realize excellent plating property when plating the surface of the insulating layer without additional pretreatment in a subsequent multilayer printed circuit board manufacturing process. It was confirmed through the experiment to complete the invention.

In addition, since the final manufactured insulating layer includes a cured product of a thermosetting resin, which is a non-photosensitive insulating material, the content of the photoinitiator or polymerization inhibitor is greatly reduced than that of the conventional manufacturing of the insulating layer through the photosensitive insulating material, thereby preventing photoinitiator or polymerization. It is possible to manufacture an insulating layer having excellent mechanical properties, such as reduced interfacial desorption with an insulating layer or a conductive layer which can be generated by the agent.

The insulating layer manufacturing method may include forming a patterned protective layer on a multilayer structure including at least two metal layers formed on a polymer resin layer including an alkali-soluble resin and a thermosetting binder.

Specifically, the step of forming a patterned protective layer on the multilayer structure comprising at least two metal layers formed on the polymer resin layer comprising the alkali-soluble resin and the thermosetting binder, the number of polymers including the alkali-soluble resin and the thermosetting binder Forming a multilayer structure comprising at least two metal layers on the ground layer; And forming a patterned protective layer on the multilayer structure.

Although the specific structure of the said multilayer structure is not specifically limited, For example, the structure in which the said polymer resin layer is laminated | stacked on the board | substrate and at least 2 or more metal layers are laminated | stacked on the said polymer resin layer is mentioned. An example of a method of forming the multilayer structure is not particularly limited, and for example, a method of laminating the polymer resin layer and the substrate after laminating the polymer resin layer on at least two or more metal layers may be used.

The at least two metal layers may include a first metal layer having a thickness of 1 nm to 500 nm; And a second metal layer having a thickness of 0.1 μm to 500 μm formed on the first metal layer. As the first metal layer has a thickness in the above-described range, it is possible to reduce the aspect ratio of the via hole formed inside the insulating layer in the method of manufacturing the insulating layer, thereby forming a fine pattern having a width / spacing of 50 μm or less. Can be implemented. In addition, in the multilayer printed circuit board manufacturing process (for example, SAP or MSAP) to be described later, since the first metal layer may serve as a seed layer, there is an advantage of not having to form a separate metal seed layer. High circuit adhesion can be achieved.

The ratio of the thickness of the second metal layer to the thickness of the first metal layer may be 10 to 10000, or 100 to 1000, or 300 to 500. As such, since the second metal layer has a thicker thickness than the first metal layer, the second metal layer may serve as a carrier layer. Specifically, for example, in the process of forming a first metal layer on the second metal layer, and then forming a polymer resin layer on the first metal layer and laminating the laminate with a substrate, the second metal layer is a laminate The efficiency of the movement and lamination process can be improved.

The first metal layer may include a metal having a specific resistance of 1000 nPa · m or less, or 500 nPa · m or less as measured at 20 ° C. Since the specific resistance of the metal included in the first metal layer is less than 1000 nΩ · m, the first metal layer may serve as a seed layer as described above.

The first metal included in the first metal layer and the second metal included in the second metal layer may be the same or different from each other, and each example is not limited thereto, and a well-known metal may be used without limitation. More specific examples of the first metal and the second metal, for example, independently of copper (Cu), gold (Au), silver (Ag), aluminum (Al), nickel (Ni), tin (Sn), and lead ( Pb), zinc (Zn), titanium (Ti), two or more kinds of these alloys, and the like can be used.

The polymer resin layer refers to a film formed through drying or curing of the polymer resin composition including an alkali-soluble resin and a thermosetting binder.

The polymer resin layer may exist alone or in a state formed on a substrate including a semiconductor material such as a circuit board, a sheet, a multilayer printed wiring board, and an example of a method of forming the polymer resin layer on a substrate is greatly limited. However, for example, a method of directly coating the polymer resin composition on a substrate or in a state in which the polymer resin composition is applied on a carrier film, and then performing a coating to remove a carrier film or a polymer on the first metal layer. The method of laminating with a base material etc. in the state which apply | coated the resin composition can be used.

The polymer resin layer may have a thickness of 0.1 μm to 500 μm. The ratio of the thickness of the polymer resin layer to the thickness of the first metal layer may be 10 to 10000, or 100 to 1000, or 400 to 600.

The polymer resin layer may include 1 part by weight to 50 parts by weight, or 10 parts by weight to 30 parts by weight with respect to 100 parts by weight of the alkali-soluble resin. When the content of the thermosetting binder is excessively high, the developability of the polymer resin layer may be lowered, and the strength may be lowered. On the contrary, when the content of the thermosetting binder is too low, not only the polymer resin layer is excessively developed, but also uniformity may be reduced during coating.

The thermosetting binder may be a thermosetting functional group, for example, an epoxy group, an oxetanyl group, a cyclic ether group, a cyclic thio ether group, a cyanide group, a maleimide group, a benzoxazine group or these It may contain two or more kinds of. Such a thermosetting binder may form a crosslinking bond with an alkali-soluble resin or the like by thermosetting to secure heat resistance or mechanical properties of the insulating layer.

More specifically, for example, as the thermosetting binder, a resin containing two or more cyclic ether groups and / or cyclic thioether groups (hereinafter referred to as cyclic (thio) ether groups) in a molecule may be used, or 2 A functional epoxy resin can be used. The thermosetting binder containing two or more cyclic (thio) ether groups in the molecule may be a compound having any one or two or more of three, four or five membered cyclic ether groups, or cyclic thioether groups in the molecule. have.

In addition, the thermosetting binder may be a polyfunctional epoxy compound including at least two or more epoxy groups in a molecule, a polyfunctional oxetane compound including at least two or more oxetanyl groups in a molecule, or an episulfide resin including two or more thioether groups in a molecule , A polyfunctional cyanate ester compound including at least two or more cyanide groups in a molecule, or a multifunctional benzoxazine compound or the like including at least two or more benzoxazine groups in a molecule.

Specific examples of the polyfunctional epoxy compound include bisphenol A type epoxy resins, hydrogenated bisphenol A type epoxy resins, brominated bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, novolac type epoxy resins, and phenols. Novolac type epoxy resin, Cresol novolac type epoxy resin, N-glycidyl type epoxy resin, bisphenol A novolac type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin, chelate type epoxy resin, glyoxal type Epoxy resin, amino group-containing epoxy resin, rubber modified epoxy resin, dicyclopentadiene phenolic epoxy resin, diglycidyl phthalate resin, heterocyclic epoxy resin, tetraglycidyl xylenoylethane resin, silicone modified epoxy resin, ε -A caprolactone modified epoxy resin, etc. are mentioned. In addition, in order to impart flame retardancy, those in which atoms such as phosphorus are introduced into the structure may be used. By thermosetting these epoxy resins, characteristics, such as adhesiveness of a cured film, solder heat resistance, and electroless plating resistance, are improved.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [( 3-methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methylacrylic Latex, (3-ethyl-3-oxetanyl) methylacrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate, these In addition to polyfunctional oxetanes such as oligomers and copolymers, oxetane alcohols and novolac resins, poly (p-hydroxystyrenes), cardo-type bisphenols, charixarenes, carlixresolecinarenes, or silses And etherates with resins having hydroxy groups such as quoxane. In addition, the copolymer etc. of the unsaturated monomer which has an oxetane ring, and an alkyl (meth) acrylate are mentioned.

Examples of the multifunctional cyanate ester compound include bisphenol A type cyanate ester resin, bisphenol E type cyanate ester resin, bisphenol F type cyanate ester resin, bisphenol S type cyanate ester resin, bisphenol M type cyanate ester resin, Novolac cyanate ester resins, phenol novolac cyanate ester resins, cresol novolac cyanate ester resins, novolac cyanate ester resins of bisphenol A, biphenol cyanate ester resins or oligomers or air thereof Coalescence, etc. are mentioned.

Examples of the polyfunctional maleimide compound include 4,4'-diphenylmethane bismaleimide, phenylmethane bismaleimide, and m-phenylmethane bismaleimide (m- phenylmethane bismaleimide), bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide (3, 3´-dimethyl-5,5´-diethyl-4,4´-diphenylmethane bismaleimide), 4-methyl-1,3-phenylene bismaleimide, 1,6 ′ -Bismaleimide- (2,2,4-trimethyl) hexane (1,6′-bismaleimide- (2,2,4-trimethyl) hexane) and the like.

Examples of the multifunctional benzoxazine compounds include bisphenol A benzoxazine resins, bisphenol F benzoxazine resins, phenolphthalein benzoxazine resins, thiodiphenol type benzoxazine resins, dicyclopentadiene benzoxazine resins, and 3,3 '. -(Methylene-1,4-diphenylene) bis (3,4-dihydro-2H-1,3-benzoxazine (3,3 '-(methylene-1,4-diphenylene) bis (3,4- dihydro-2H-1,3-benzoxazine) resin and the like.

As a compound which has two or more cyclic thioether group in the said molecule | numerator, bisphenol A episulfide resin YL7000 by the Japan epoxy resin company, etc. are mentioned, for example. Moreover, episulfide resin etc. which substituted the oxygen atom of the epoxy group of the novolak-type epoxy resin with the sulfur atom can also be used. Moreover, YDCN-500-80P of Kukdo Chemical Co., Ltd. phenol novolak-type cyanide ester resin PT-30S of Lonza Corporation, phenylmethane type maleimide resin BMI-2300 of Daiwa Corporation, Pd type benzoxazine of Shikoku Corporation Resin and the like can be used.

The alkali soluble resin may include a carboxyl group or a phenol group-containing resin. Such alkali-soluble resins include a carboxyl group, and the polymer resin layer exhibits a higher alkali developability, and a development rate of the polymer resin layer can be controlled by showing a lower developability than a carboxyl group including a phenol group. The said carboxyl group-containing resin and phenol group containing resin can be used individually or in mixture.

As said carboxyl group or phenol group containing resin, well-known and common carboxyl group-containing resin or phenol group containing resin which contains a carboxyl group or a phenol group in a molecule | numerator can be used.

As an example of the said carboxyl group-containing resin, resin of (1)-(7) enumerated below is mentioned.

(1) carboxyl group-containing resin obtained by making a polyfunctional epoxy resin react with saturated or unsaturated monocarboxyl group, and then making polybasic acid anhydride react,

(2) a carboxyl group-containing resin obtained by reacting a bifunctional phenol and / or a dicarboxyl group with a bifunctional epoxy resin, followed by reacting a polybasic anhydride,

(3) carboxyl group-containing resin obtained by making a polyfunctional phenol resin react with the compound which has one epoxy group in a molecule | numerator, and then reacting polybasic acid anhydride,

(4) Carboxyl group-containing resin formed by making polybasic acid anhydride react with the compound which has two or more alcoholic hydroxyl groups in a molecule | numerator.

(5) Polyamic acid resin or copolymer resin of polyamic acid resin which reacted diamine and dianhydride

(6) polyacrylic acid resin or copolymer of polyacrylic acid resin reacted with acrylic acid

(7) resins prepared by ring opening anhydrides of polymaleic anhydride resins and polymaleic anhydride resin copolymers reacted with maleic anhydride with weak acids, diamines, imidazoles, and dimethyl sulfoxides; Although it is mentioned, it is not limited to these.

More specific examples of the carboxyl group-containing resin include CCR-1291H from Nippon Kayaku Co., SHA-1216CA60 from Shina T & C, Noverite K-700 from Lubrizol, or a mixture of two or more thereof.

Although the example of the said phenol group containing resin is not restrict | limited greatly, For example, novolak resins, such as a phenol novolak resin, cresol novolak resin, bisphenol F (BPF) novolak resin, or 4,4 '-(1- (4 -(2- (4-hydroxyphenyl) propan-2-yl) phenyl) ethane-1,1-diyl) diphenol [4,4´- (1- (4- (2- (4-Hydroxyphenyl) bisphenol A resins such as propan-2-yl) phenyl) ethane-1,1-diyl) diphenol] may be used alone or in combination.

The polymer resin layer may further include at least one additive selected from the group consisting of a thermosetting catalyst, an inorganic filler, a leveling agent, a dispersant, a mold release agent, and a metal adhesion promoter.

The thermosetting catalyst serves to promote thermosetting of the thermosetting binder. As said thermosetting catalyst, for example, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, Imidazole derivatives such as 1-cyanoethyl-2-phenylimidazole and 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; Amines such as dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, 4-methyl-N, N-dimethylbenzylamine compound; Hydrazine compounds such as adipic dihydrazide and sebacic acid dihydrazide; Phosphorus compounds, such as a triphenylphosphine, etc. are mentioned. Moreover, as what is marketed, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (all are brand names of an imidazole compound) by the Shikoku Kasei Kogyo Co., Ltd., U-CAT3503N and UCAT3502T by San Apro Corporation (All are brand names of block isocyanate compounds of dimethylamine), DBU, DBN, U-CATS A102, U-CAT5002 (both bicyclic amidine compounds and salts thereof) and the like. It is not specifically limited to these, The thermosetting catalyst of an epoxy resin or an oxetane compound, or the thing which accelerates reaction of an epoxy group and / or an oxetanyl group, and a carboxyl group can also be used, and can also be used individually or in mixture of 2 or more types. . Also, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-4,6-diamino-S-tri Azine, 2-vinyl-4,6-diamino-S-triazine-isosauranuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine-isosaanuric acid S-triazine derivatives, such as an adduct, can also be used, Preferably, the compound which also functions as these adhesive imparting agents can be used together with the said thermosetting catalyst.

Examples of the inorganic filler include silica, barium sulfate, barium titanate, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, mica or a mixture of two or more thereof. Examples of the silica include SC2050-FNB (manufactured by Admatechs).

Examples of the release agent include polyalkylene waxes such as low molecular weight polypropylene and low molecular weight polyethylene, ester wax, carnauba wax, paraffin wax and the like.

The metal adhesion promoter may be a material that does not cause problems in surface alteration or transparency of the metal material, for example, a silane coupling agent or an organometallic coupling agent.

The leveling agent serves to remove the popping or crater of the surface when the film coating, for example, BYK-380N, BYK-307, BYK-307, BYK-378, BYK-350 of BYK-Chemie GmbH may be used.

In addition, the polymer resin layer may further include a resin or an elastomer having an epoxy equivalent of 5000 or more. Accordingly, the roughening treatment of the cured product of the polymer resin layer may be possible.

In addition, the polymer resin layer may further include an alkali-soluble resin including a thermosetting binder or a photoreactive unsaturated group and a photoinitiator in order to impart photocurable properties to the polymer resin layer. Specific examples of the thermosetting binder including the photoreactive unsaturated group, the alkali-soluble resin including the photoreactive unsaturated group and the photoinitiator are not particularly limited, and various compounds used in the art related to the photocurable resin composition may be used without limitation.

Meanwhile, in the forming of the patterned protective layer on the multilayer structure, the protective layer may include a photosensitive resin layer or a third metal layer. Examples of the photosensitive resin layer include alkali-soluble or non-thermosetting photosensitive dry film resists (DFR), and examples of the third metal layer include metals such as gold, silver copper, tin, nickel aluminum, titanium, and the like. The metal layer containing the alloy etc. containing 2 or more types of mixtures is mentioned.

Forming the patterned protective layer on the multilayer structure may include exposing and developing the photosensitive resin layer formed on the multilayer structure. In this case, the photosensitive resin layer may be used as a protective layer.

The photosensitive resin layer may have a thickness of 1 μm to 500 μm, or 3 μm to 200 μm, or 5 μm to 100 μm. When the thickness of the photosensitive resin layer is excessively increased to more than 500 μm, the resolution of the pattern formed on the multilayer structure may be reduced.

In the step of exposing and developing the photosensitive resin layer formed on the multilayer structure, the method of forming the multilayer structure photosensitive resin layer is not particularly limited. For example, the photosensitive resin in the form of a film, such as a photosensitive dry film resist, may be multilayered. The method of laminating | stacking on a structure or the method of coating the photosensitive resin composition on a multilayer structure by the spraying or dipping method, and crimping | bonding can be used.

In the step of exposing and developing the photosensitive resin layer formed on the multilayer structure, an example of a method of exposing the photosensitive resin layer is not particularly limited. For example, a photomask having a predetermined pattern formed on the photosensitive resin layer is applied. Contact and irradiate ultraviolet rays, or by imaging a predetermined pattern included in the mask through the projection objective lens and then irradiating ultraviolet rays, or directly by using a laser diode as a light source and then irradiating ultraviolet rays And the like can be selectively exposed. Under the present circumstances, as an example of ultraviolet irradiation conditions, irradiation with the light quantity of 5mJ / cm <2> -600mJ / cm <2> is mentioned.

In addition, in the step of exposing and developing the photosensitive resin layer formed on the multilayer structure, an example of a method of developing the photosensitive resin layer may be a method of treating an alkali developer. Examples of the alkaline developer are not particularly limited, but for example, alkaline aqueous solutions such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, tetramethylammonium hydroxide, and amines may be used. The specific amount of the alkaline developer is not particularly limited.

The forming of the patterned protective layer on the multilayer structure may include forming a third metal layer on the multilayer structure; Forming a patterned photosensitive resin layer on the third metal layer; And etching the third metal layer in a state in which the third metal layer is blocked by the patterned photosensitive resin layer. In this case, the third metal layer may be used as a protective layer.

In the forming of the third metal layer on the multilayer structure, an example of a method of forming a third metal layer on the multilayer structure may include a method of depositing a third metal on the multilayer structure. An example of a method of depositing a third metal on the multilayer structure is not particularly limited. For example, a metal sputtering method or a chemical vapor deposition (CVD) method may be used.

In the forming of the third metal layer on the multilayer structure, the thickness of the third metal layer formed on the multilayer structure may be 10 nm to 5 μm. When the thickness of the third metal layer is excessively increased to more than 5 μm, as an excess metal is required to form the third metal layer, raw material costs may increase and efficiency may be reduced in terms of economy.

Meanwhile, forming the patterned photosensitive resin layer on the third metal layer may include exposing and developing the photosensitive resin layer formed on the third metal layer.

The thickness of the photosensitive resin layer formed on the third metal layer may be 0.1 μm to 500 μm. When the thickness of the photosensitive resin layer is excessively increased to more than 500 μm, the resolution of the pattern formed on the third metal layer may decrease.

Specific details of the step of exposing and developing the photosensitive resin layer formed on the third metal layer include the above-described details in the step of exposing and developing the photosensitive resin layer formed on the multilayer structure.

In the etching of the third metal layer in a state in which the third metal layer is blocked by the patterned photosensitive resin layer, the patterned photosensitive resin layer is used as a resist for forming a pattern on the third metal layer.

Therefore, the state in which the third metal layer is blocked by the patterned photosensitive resin layer means a state in which the photosensitive resin layer patterned on the surface of the third metal layer prevents contact between the third metal layer and the etching solution. As a result, a pattern may be formed on the third metal layer while being blocked by the patterned photosensitive resin layer and exposing a portion of the exposed third metal layer.

The etching solution may be selected according to the type of the metal layer, and it is preferable to use a material which has little influence on the lower copper line and does not affect the lower multilayer structure.

Meanwhile, the method of manufacturing the insulating layer may include etching the metal layer in a state in which the metal layer is blocked with the patterned protective layer.

In the present specification, a pattern may mean a specific shape that is finally remaining by a process of removing portions other than a specific shape to be left with respect to a material having a form of a thin film or a layer. As used herein, "patterned" also means "patterned".

That is, the pattern formed on the protective layer is used as a resist for forming a pattern on the metal layer. Therefore, the blocking state of the metal layer with the patterned protective layer means a state in which the protective layer patterned on the surface of the metal layer prevents contact between the metal layer and the etching solution. Accordingly, a pattern may be formed on the metal layer while the metal layer is not blocked by the patterned protective layer and the exposed metal layer is removed.

Specifically, forming the patterned metal layer by etching the metal layer in the blocked state with the patterned protective layer may include patterning the second metal layer by etching the second metal layer while the metal layer is blocked with the patterned protective layer. Forming a second metal layer; And etching the first metal layer in a state in which the first metal layer is blocked by the patterned second metal layer.

Etching the second metal layer to form a patterned second metal layer by blocking the metal layer with the patterned protective layer; And etching the first metal layer in a state in which the first metal layer is blocked with the patterned second metal layer. The etching may be performed simultaneously or sequentially, but may be performed sequentially. Accordingly, the first metal layer may be prevented from being etched at the same time in the etching of the second metal layer, thereby preventing the polymer resin layer from being removed by direct contact between the polymer resin layer disposed under the first metal layer and the etching solution. have.

The method may further include removing the patterned second metal layer after etching the first metal layer in a state in which the first metal layer is blocked by the patterned second metal layer. For example, a photoresist stripping solution, a desmear process, plasma etching, or the like may be used as a more specific method of removing the patterned second metal layer, and the above methods may be used in combination.

On the other hand, the insulating layer manufacturing method may further include the step of removing the patterned protective layer after the step of forming a patterned metal layer by etching while blocking the metal layer with the patterned protective layer, As a specific example of removing the patterned protective layer, for example, removing the third metal layer pattern remaining on the second metal layer or removing the patterned photosensitive resin layer remaining on the second metal layer. It may further comprise a step. More specifically, for example, the photoresist stripping solution may be treated, a desmear process, plasma etching, or the like may be performed, and the above methods may be used in combination.

In addition, the insulating layer manufacturing method may include a step of alkali development in a state in which the polymer resin layer is blocked with the patterned metal layer. As described above, the patterned metal layer may include a patterned first metal layer, wherein only a part of the surface of the polymer resin layer exposed through the pattern formed on the first metal layer is selectively contacted with the alkaline developer. By replacing the conventional laser etching process, it is possible to secure more than the equivalent level of precision and higher process economics.

In the alkali development in the state where the polymer resin layer is blocked with the patterned metal layer, the patterned metal layer is used as a resist for forming a pattern on the polymer resin layer.

Therefore, the state in which the polymer resin layer is blocked with the patterned metal layer means a state in which the patterned metal layer prevents contact between the polymer resin layer and alkali on the surface of the polymer resin layer. Accordingly, a pattern may be formed on the polymer resin layer while being blocked by the patterned metal layer and exposing a portion of the exposed polymer resin layer.

As the polymer resin layer includes an alkali soluble resin, since the polymer resin layer has alkali solubility dissolved by an alkali developer, a portion of the polymer resin layer in contact with the alkali developer may be dissolved and removed.

Examples of the alkaline developer are not particularly limited, but for example, alkaline aqueous solutions such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, tetramethylammonium hydroxide, and amines may be used. The specific amount of the alkaline developer is not particularly limited.

In addition, the insulating layer manufacturing method may include a step of thermosetting the polymer resin layer after the alkali development. Thermosetting the polymer resin layer may be performed at a temperature of 100 ℃ to 300 ℃. As the polymer resin is thermally cured after the pattern is formed on the polymer resin layer, a finer pattern can be realized as compared to the method of thermosetting the conventional polymer resin first and forming the pattern through etching using a laser. have.

Meanwhile, according to another embodiment of the present invention, a method of manufacturing a multilayer printed circuit board including forming a patterned metal substrate on the insulating layer manufactured in the above embodiment may be provided.

The inventors of the present invention, as the insulating layer prepared in the embodiment includes a predetermined pattern, in the process of newly laminating a metal substrate on the insulating layer, as the inside of the pattern is filled with a metal, based on the insulating layer The invention was completed by confirming that the metal substrates located below and are connected to each other to manufacture a multilayer printed circuit board.

In particular, the insulating layer prepared in the embodiment may include a polymer resin layer including an alkali-soluble resin and a thermosetting binder of the thermosetting binder and a metal layer formed on the surface of the polymer resin layer. The content of the alkali-soluble resin, the thermosetting binder and the metal layer includes the details described above in the embodiment.

As such, as the insulating layer includes not only a polymer resin layer but also a metal layer formed on the surface of the polymer resin layer, a microcircuit pattern forming process known as Semi Additive Process (SAP) or Modified Semi Additive Process (MSAP) is known in the art. Application can be easy.

Specifically, the MSAP process refers to a case in which a microcircuit pattern is formed in a state in which a metal thin film having a thickness of 5 μm or less is formed on the insulating layer, and as the metal layer included in the insulating layer serves as a metal thin film, The process for forming the metal thin film may not be required.

The forming of the patterned metal substrate on the insulating layer may include: plating the surface of the insulating layer with a patterned photosensitive resin layer formed on the insulating layer; And removing the photosensitive resin layer.

In the state in which the patterned photosensitive resin layer is formed on the insulating layer, plating the surface of the insulating layer may include, but is not limited to, an example of a method of forming the patterned photosensitive resin layer on the insulating layer. For example, a method of applying, exposing and developing a photosensitive resin layer on the insulating layer can be used. Information on the exposure and development of the photosensitive resin layer includes the above-described information in the embodiment.

Examples of the method of plating the surface of the insulating layer are not particularly limited, but electrolytic plating or electroless plating can be used, for example. The electroplating method is a method of covering the surface of the negative electrode with another metal using electrolysis, and the electroless plating method is a method of depositing the metal in the solution on the material surface by using a reducing action. Examples of the metal are not particularly limited, but a copper metal can be used.

Meanwhile, the plating of the surface of the insulating layer may further include forming a fine metal thin film layer on an inner surface of the insulating layer in order to increase the plating property of the insulating layer. The inner surface of the insulating layer refers to a surface in which the insulating layer is in contact with the via hole generated by the internal pattern. Since the metal layer is not formed in the portion in contact with the via hole, a micrometal thin film layer may be introduced to compensate for this.

An example of a method of forming the fine metal thin film layer is not particularly limited, and for example, a direct metallization method may be used, and the direct metallization method is a method of introducing a metal to the surface of a non-conductive substrate. However, the example is not particularly limited, and the direct metallization method, which is widely known in the art of manufacturing a printed circuit board, may be used without limitation.

On the other hand, in the step of removing the photosensitive resin layer, for example, a method of treating a photoresist stripping solution, etc. may be mentioned as the photosensitive resin layer removing method.

After removing the photosensitive resin layer, the method may further include etching the insulating layer in a state in which the insulating layer is blocked with the patterned metal substrate, thereby forming a metal layer on the surface of the insulating layer. Some may be etched. Details of the etching method include those described above in the above embodiment.

According to the present invention, it is possible to realize uniform and fine patterns while improving efficiency in terms of cost and productivity, and multilayer printing using an insulating layer manufacturing method capable of securing excellent mechanical properties and an insulating layer obtained from the insulating layer manufacturing method. A circuit board manufacturing method may be provided.

Figure 1 schematically shows an insulating layer manufacturing process of the embodiment.
2 schematically shows a manufacturing process of a multilayer printed circuit board of an embodiment.

The invention is explained in more detail in the following examples. However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited by the following examples.

Example: Fabrication of Insulation Layer and Multilayer Printed Circuit Board

(1) Preparation of Insulation Layer

Titanium metal layer (4) by depositing titanium (Ti) metal to a thickness of 30 nm using sputtering while supplying a gas mixture of argon and oxygen to the deposition equipment on the surface of an electrolytic copper foil layer (manufactured by Iljin Materials) having a thickness of 12 µm. Formed. 30 g of SHA-1216CA60 (manufactured by Shin-A T & G) with an alkali-soluble resin on the titanium layer 4, 6 g of YDCN-500-8P (manufactured by Kukdo Chemical Co., Ltd.) with a thermosetting binder, 0.2 g of 2E4MZ (manufactured by Shikoku Chem) with a thermosetting catalyst, and The polymer resin composition mixed with 25 g of silica SC2050-FNB (manufactured by Admatechs) was applied and dried to form a polymer resin layer (1) having a thickness of 15 µm, and then copper lines (2) were formed on the copper-clad laminate (3). The polymer resin layer was vacuum laminated at 80 ° C. on a circuit board. (See <1> in Figure 1 below)

A 15 μm thick photosensitive dry film resist KL1015 (manufactured by Kolon Industries) 6 on the electrolytic copper foil layer 5 was laminated at 110 ° C., and a circular negative of 30 μm in diameter was formed on the photosensitive dry film resist 6. The photomask was contacted, irradiated with ultraviolet light (amount of light of 25 mJ / cm 2), and then the dry film resist 6 was developed through a 30 ° C. 1% sodium carbonate developer to form a constant pattern. <3> reference)

And the copper etching liquid was processed and the said electrolytic copper foil layer 5 was removed. At this time, the patterned photosensitive dry film resist 6 acted as a protective layer of the electrolytic copper foil layer 5, thereby forming the same pattern as the photosensitive dry film resist 6 on the electrolytic copper foil layer 5. (See <4> in Figure 1 below)

Thereafter, the dry film resist 6 was removed through a 50 ° C. 3% sodium hydroxide dry film resist stripper. (See <5> in FIG. 1 below)

Then, the titanium etching solution was treated to remove the titanium layer 4. At this time, the patterned electrolytic copper foil layer 5 acted as a protective layer of the titanium layer 4, thereby forming the same pattern as the electrolytic copper foil layer 5 on the titanium layer 4. (See <6> in Figure 1 below)

Thereafter, the electrolytic copper foil layer 5 was removed using a copper etching solution. (See <7> in Figure 1 below)

Then, the polymer resin layer 1 was developed by treating 30 ° C. 1% sodium carbonate developer. At this time, the patterned titanium layer 4 acted as a protective layer of the polymer resin layer 1 to form the same pattern as the titanium layer 4 in the polymer resin layer 1. Thereafter, the patterned polymer resin layer 1 was thermally cured at a temperature of 200 ° C. for 1 hour to prepare an insulating layer. (See <8> in Figure 1 below)

(2) Manufacture of multilayer printed circuit board

A black hole chemical (manufactured by Macdermid) was treated on the inner wall of the via hole 7 inside the insulating layer to form a seed layer 8 through direct metallization. (See <2> in Figure 2 below)

Thereafter, the photosensitive resin layer was exposed and developed on the titanium layer 4 to form a patterned photosensitive resin layer 9. (See <3> in Figure 2 below)

The metal substrate 10 made of copper was formed on the inside of the via hole 7 and the titanium layer 4 through electroplating. (See <4> in Figure 2 below)

Next, the patterned photosensitive resin layer 9 is removed using a photosensitive resin stripper to form a pattern on the metal substrate 10 (see <5> in FIG. 2 below). The layer 4 was removed to prepare a multilayer printed circuit board. At this time, the patterned metal substrate 10 acted as a protective layer of the titanium layer 4 to form the same pattern as the metal substrate 10 on the titanium layer 4. (See <6> in Figure 2 below)

Comparative Example: Fabrication of Insulation Layer and Multilayer Printed Circuit Board

(1) Preparation of Insulation Layer

Without forming the titanium metal layer 4, 30 g of SHA-1216CA60 (manufactured by Shin-a T & G) with an alkali-soluble resin on the surface of an electrolytic copper foil layer (manufactured by Iljin Materials) having a thickness of 12 µm, and 6 g of YDCN-500-8P (manufactured by Kukdo Chemical) with a thermosetting binder A polymer resin composition was prepared by mixing 0.2 g of 2E4MZ (manufactured by Shikoku Chem) and 25 g of silica SC2050-FNB (manufactured by Admatechs) as a thermosetting catalyst, followed by drying to form a polymer resin layer having a thickness of 15 μm. The polymer resin layer was vacuum laminated at 80 ° C. on the circuit board on which copper lines were formed, and the polymer resin layer was thermally cured at a temperature of 200 ° C. for 1 hour.

A 15 μm thick photosensitive dry film resist KL1015 (manufactured by Kolon Industries) was laminated on the electrolytic copper foil layer at 110 ° C., and a circular negative photomask having a diameter of 30 μm was contacted on the photosensitive dry film resist, and irradiated with ultraviolet rays. (Light amount of 25 mJ / cm 2), and then the dry film resist was developed through a 30 ° C. 1% sodium carbonate developer to form a constant pattern.

And the copper etching liquid was processed and the said electrolytic copper foil layer was removed. At this time, the patterned photosensitive dry film resist acted as a protective layer of the electrolytic copper foil layer, thereby forming the same pattern as the photosensitive dry film resist on the electrolytic copper foil layer.

Thereafter, the dry film resist was removed through a 50 ° C. 3% sodium hydroxide dry film resist stripper.

Then, the polymer resin layer was etched with a CO 2 laser drill along the patterned electrolytic copper foil layer pattern to prepare an insulating layer having via holes having the same pattern as the electrolytic copper foil layer.

(2) Manufacture of multilayer printed circuit board

A multilayer printed circuit board was manufactured in the same manner as in the above example, except that the insulating layer prepared in Comparative Example was used.

Experimental Example: Measurement of Physical Properties of Insulation Layer Obtained in Examples and Comparative Examples

The physical properties of the insulating layer obtained in the Examples and Comparative Examples were measured by the following method, the results are shown in Table 1.

1. Via Hole Plating

About the insulating layer obtained by the said Example and the comparative example, the plating property of the via hole inside an insulating layer was confirmed on the following reference | standard.

OK: No peeling from the insulating layer, no lifting of the plated metal.

NG: Lifting of the metal peeled or plated from the insulating layer occurs.

2. Minimum pattern width (µm) and spacing (µm)

For the insulating layers obtained in the above Examples and Comparative Examples, the width of the upper opening surface (pattern) and the space between the patterns were measured through an optical microscope.

The experimental results of the insulating layers of the Examples and Comparative Examples are shown in Table 1 below.

Experimental Example Results for the Insulation Layer of Examples and Comparative Examples division Via Hole Plating Pattern width (μm) Pattern spacing (μm) EXAMPLE OK 8 8 Comparative example NG 15 15

As shown in Table 1, in the case of the comparative insulating layer in which the via hole was formed by etching the thermosetting resin layer using a CO 2 laser drill, the minimum pattern width was 15 μm and the minimum interval between the patterns was 15 μm. In the case of the insulating layer manufactured in Example, the minimum pattern width was reduced to 8㎛, the minimum interval between patterns to 8㎛, it was confirmed that the finer pattern can be implemented in the insulating layer of the embodiment.

In addition, in the case of the insulating layer manufactured in the comparative example, it was confirmed that the plating property to the internal via hole was poor, and interface desorption between the insulating layer and the conductive layer occurred. On the other hand, in the case of the insulating layer of the above embodiment, the interfacial junction between the insulating layer and the conductive layer is maintained, the plated metal surface is uniformly formed, it was confirmed that the excellent plating properties and structural stability.

1: polymer resin layer
2: copper circuit
3: copper clad laminate
4: titanium layer
5: electrolytic copper foil layer
6: Photosensitive Dry Film Resist (DFR)
7: via hole
8: seed layer
9: patterned photosensitive resin layer
10: metal substrate
<1> to <8>: Process sequence of a process

Claims

Forming a patterned protective layer on the multilayer structure including at least two metal layers formed on the polymer resin layer comprising an alkali soluble resin and a thermosetting binder;
Etching the metal layer with the patterned protective layer to form a patterned metal layer;
Alkali developing in a state in which a polymer resin layer is blocked with the patterned metal layer; And
And thermosetting the polymer resin layer;
Etching the metal layer with the patterned protective layer in a blocked state to form a patterned metal layer,
Etching the second metal layer while blocking the metal layer with the patterned protective layer to form a patterned second metal layer; And etching the first metal layer in a state in which the first metal layer is blocked by the patterned second metal layer.

The method of claim 1,
The at least two metal layers,
A first metal layer having a thickness of 1 nm to 500 nm; And a second metal layer having a thickness of 0.1 μm to 500 μm formed on the first metal layer.

The method of claim 2,
The ratio of the thickness of the second metal layer to the thickness of the first metal layer is 10 to 10000, the insulating layer manufacturing method.

The method of claim 2,
The ratio of the polymer resin layer thickness to the thickness of the first metal layer is 10 to 10000, the insulating layer manufacturing method.

The method of claim 2,
The first metal layer comprises a metal having a specific resistance of 1000 nPa · m or less measured at 20 ° C.

delete

The method of claim 1,
Etching the second metal layer while blocking the metal layer with the patterned protective layer to form a patterned second metal layer; And etching the first metal layer in a state in which the first metal layer is blocked by the patterned second metal layer.

The method of claim 1,
The protective layer comprises a photosensitive resin layer or a third metal layer, insulating layer manufacturing method.

The method of claim 1,
Forming a patterned protective layer on the multilayer structure,
Exposing and developing the photosensitive resin layer formed on the multilayer structure.

The method of claim 1,
Forming a patterned protective layer on the multilayer structure,
Forming a third metal layer on the multilayer structure; Forming a patterned photosensitive resin layer on the third metal layer; And etching the third metal layer in a state in which the third metal layer is blocked by the patterned photosensitive resin layer.

The method of claim 1,
After forming the patterned metal layer by etching while blocking the metal layer with the patterned protective layer,
Removing the patterned protective layer.

The method of claim 1,
After etching the first metal layer while blocking the first metal layer with the patterned second metal layer,
And removing the patterned second metal layer.

The method of claim 1,
Thermosetting the polymer resin layer is carried out at a temperature of 100 ℃ to 300 ℃, insulating layer manufacturing method.

The method of claim 1,
The polymer resin layer comprises 1 part by weight to 50 parts by weight of the thermosetting binder with respect to 100 parts by weight of the alkali-soluble resin, insulating layer manufacturing method.

The method of claim 1,
The thermosetting binder includes at least one functional group selected from the group consisting of an epoxy group, an oxetanyl group, a cyclic ether group, a cyclic thio ether group, a cyanide group, a maleimide group and a benzoxazine group.

The method of claim 1,
The said alkali-soluble resin contains a carboxyl group or phenol group containing resin, The manufacturing method of the insulating layer.

A method of manufacturing a multilayer printed circuit board, comprising the step of forming a patterned metal substrate on the insulating layer prepared by claim 1.

The method of claim 17,
The insulating layer comprises a polymer resin layer including an alkali-soluble resin and a thermoset of a thermosetting binder and a metal layer formed on the surface of the polymer resin layer, multilayer printed circuit board manufacturing method.

The method of claim 17,
Forming the patterned metal substrate on the insulating layer,
Plating the surface of the insulating layer with a patterned photosensitive resin layer formed on the insulating layer; And
Removing the photosensitive resin layer; comprising, a multilayer printed circuit board manufacturing method.

The method of claim 19,
After removing the photosensitive resin layer,
And etching the insulating layer while the insulating layer is blocked with the patterned metal substrate.