JP2000151120A - Manufacture of multilayer printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a multilayer printed wiring board with excellent etching precision of interlayer connecting holes. SOLUTION: In this manufacture of a multilayer printed wiring board using an epoxy resin curing compound containing halogen atoms for insulating layers, interlayer connecting holes are formed by removing the resin curing compound provided in the portions to be the interlayer connecting holes by using an etching solution consisting of alkali metal compounds, an amide solvent and an alcohol solvent and the etching solution is filtrated during the treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a multilayer printed wiring board having holes for interlayer connection.

[0002]

2. Description of the Related Art In general, a multilayer printed wiring board is a resin-impregnated prepreg having a glass cloth as a base material between an inner circuit board having a circuit formed on a copper-clad laminate and a single-sided copper-clad laminate or copper foil. Then, it is heated and hardened by heating and pressurizing to form a circuit on the outer layer surface of the copper-clad laminate with the inner layer circuit bonded and integrated. With the recent miniaturization, high performance, and multi-functionality of electronic equipment, multilayer printed wiring boards have become higher density, thinner between layers, finer wiring, and smaller diameter of interlayer connection holes. Interstitial via holes that connect only adjacent wiring layers (hereinafter referred to as
It is called a via hole. ) Has been used. Recently, it has been required to reduce the diameter of the via hole in order to further increase the wiring density.

[0003] A conventional method of manufacturing a multilayer printed wiring board having via holes is, for example, to stack a plurality of prepregs and copper foil on an inner circuit board in which a circuit is formed on a copper-clad laminate, and heat and press. There is a method of forming a via hole at a predetermined position of the integrated copper-clad laminate containing an inner layer circuit by drilling a hole so as to reach the inner layer circuit. Also, a method of forming a via hole by removing only the connection hole portion of the outermost copper foil of the multilayer-bonded substrate by etching and irradiating a laser to remove the resin material of the window opening portion and irradiating a laser, for example, And Japanese Patent Publication No. 4-3676. Furthermore,
In order to form via holes, a method of selectively chemically etching a plastic part has been proposed,
Such a method is disclosed in, for example, JP-A-50-4577, JP-A-51-27464, or
As disclosed in JP-A-49068, this is a method in which a polyimide film is used as an insulating layer and etched with hydrazine or the like. Although the purpose is not to form a via hole, a method of roughening or desmearing a cured epoxy resin used for a printed wiring board with concentrated sulfuric acid, chromic acid, permanganic acid, etc. Showa 5
It is known from JP-A-4-144968 and JP-A-62-104197.

[0004] The present inventors have determined that the weight average molecular weight is 100,0.
Using a thermosetting epoxy resin composition containing an epoxy polymer of at least 00 as an interlayer insulating material, forming connection holes of a multilayer wiring board with an etchant comprising an alkali metal compound, an amide solvent, and an alcohol solvent. A method and an etching solution are proposed in Japanese Patent Application Laid-Open No. 8-325438.

[0005]

Among such conventional methods, the method of drilling a hole for a via hole to a position reaching an inner layer wiring circuit by a drill is different from the method of drilling a through hole. There is a problem that processing cannot be performed by superimposing a plurality of sheets, and processing is performed one by one, which requires a very long time and low productivity. Further, in order to control the depth of the tip of the drill, it is necessary to match the depth of the copper wiring pattern. However, since the thickness of the multilayer wiring board usually has a certain degree of variation, the thickness between the layers is larger than the set depth. When the thickness is thick, it may not reach the wiring circuit of the inner layer,
Conversely, if the thickness between the layers is smaller than the set depth, it may reach the wiring circuit in the layer below it, which causes a disconnection or short-circuit and poor conduction. In addition, 0.3m
In the case of drilling a small diameter of less than m, there is a problem that the life of the drill is remarkably reduced due to the deviation of the core of the drill and the processing of the resin layer containing the glass cloth base material.

In the via hole processing using a laser, when the insulating layer is formed of only a resin without a glass cloth base material or a material containing a resin and a small amount of an inorganic filler, a laser pulse is applied. When the energy per hit is increased, heat is stored in the hole, and the heat promotes the thermal decomposition of the resin on the wall surface of the hole, resulting in an octopus-shaped hole in which the hole wall of the resin is larger than the copper foil opening. And the plating thickness in the hole cannot be sufficiently ensured. For the same reason, even if the irradiation interval of the laser pulse is shortened, the heat accumulation is large and the heat promotes the thermal decomposition of the resin on the wall surface of the hole. There is a problem in that the shape is reduced, the exchangeability of the plating solution is reduced, and the plating thickness in the hole cannot be sufficiently secured. Therefore, it is difficult to find the optimum conditions for laser processing. In addition, since drilling by laser is performed one hole at a time, if the number of holes increases, the processing time becomes longer, and there is a problem that productivity is low.

In the method of performing chemical etching, hydrazine is highly toxic, or concentrated sulfuric acid, chromic acid, and permanganic acid are specified as specific chemical substances. There were problems of high cost and low safety. In addition, the amide-based solvent previously proposed, drilling with an etching solution composed of an alcohol-based solvent solution of an alkali metal compound, when the number of times the solution is used increases, the etching properties vary,
There is a problem that the etching accuracy is low.

An object of the present invention is to provide a method for manufacturing a multilayer printed wiring board having excellent etching accuracy for interlayer connection holes.

[0009]

The method of manufacturing a multilayer printed wiring board according to the present invention is a method of manufacturing a multilayer printed wiring board using a cured epoxy resin containing a halogen atom for an insulating layer, wherein a hole for interlayer connection is formed. A method of removing a cured resin at a portion to be a hole for interlayer connection using an etching solution comprising an alkali metal compound, an amide solvent, and an alcohol solvent, and performing the treatment while filtering the etching solution. It is characterized by.

In the cured epoxy resin, it is preferable to use a cured epoxy resin having a halogen atom content of 5 wt% or more for the insulating layer.

The cured epoxy resin includes a cured product of a halogenated polyfunctional epoxy resin and / or a cured product of a halogenated polyfunctional phenol, and a weight average molecular weight of 50,000.
Use of at least one selected from the above high molecular weight epoxy polymers, high molecular weight epoxy polymers having a weight average molecular weight of 50,000 or more using the above halogenated difunctional epoxy resin and / or halogenated difunctional phenols as raw materials. Can be. At this time, it is preferable to use a bromine atom as the halogen atom.

The amide solvent of the etching solution includes N, N
It is preferable to use at least one selected from the group consisting of -dimethylformamide, N, N-dimethylacetamide, and N-methyl-2-pyrrolidone. The alcoholic solvent of the etching solution is preferably methanol, ethanol, ethylene glycol. It is preferable to use one or more selected from the group consisting of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, triethylene glycol, tetraethylene glycol, and polyethylene glycol. It is preferable to use an etchant containing 50 to 99% by weight of an amide solvent, 0.5 to 49.5% by weight of an alcoholic solvent, and 0.5 to 40% by weight of an alkali metal compound.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The average pore size of a filter used for filtration is preferably in the range of 0.5 μm to 100 μm from the viewpoint of filtration efficiency. Depending on the material, the resistance when passing through the filter is increased, and the filtration efficiency is significantly reduced.
If it exceeds 0 μm, the ability to capture the melt of the cured epoxy resin decreases. The types of filters include glass, stainless steel, polyester, polyethylene, fluorocarbon, polypropylene, acrylic, and woven and nonwoven fabrics made of fibers such as fluorocarbon resin, stainless steel wire mesh or sintered metal filter media, polyester, polyethylene, fluorocarbon, and polypropylene. There are porous plastics and porous porcelain made of, for example, acetate, acrylic, fluororesin and the like. As the shape of the filter, a flat plate type, a cartridge type, or the like can be used.

As the epoxy resin cured product used for the insulating layer between layers, any one containing a halogen atom can be used. As a constituent of the epoxy resin cured product containing a halogen atom, epoxy resin or high molecular weight There are an epoxy polymer, a curing agent, a cross-linking agent, and the like, and any of these may contain a halogen atom. further,
If necessary, an accelerator, a catalyst, an elastomer, a filler, a flame retardant and the like may be added.

(Epoxy resin) Examples of the resin used for such an epoxy resin cured product include a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin having an epoxy group in a molecule.
Alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, diglycidyl etherified product of phenol, diglycidyl etherified product of alcohol, and There are these alkyl-substituted products, halides, hydrogenated products and the like, and these may be used in combination, and components other than the epoxy resin may be contained as impurities.

(Curing Agent) As the curing agent used for the epoxy resin cured product, any one can be used as long as it can cure the epoxy resin. For example, polyfunctional phenols, amines, imidazole compounds, acid Examples include anhydrides, organophosphorus compounds and their halides. Examples of the polyfunctional phenols include monocyclic bifunctional phenols such as hydroquinone, resorcinol, catechol, and polycyclic bifunctional phenols such as bisphenol A, bisphenol F, naphthalene diols, biphenols, and halides thereof, and alkyl group substitution. There is a body. Further, there are novolaks and resols which are polycondensates of these phenols and aldehydes. Examples of amines include aliphatic or aromatic primary amines, secondary amines, tertiary amines, quaternary ammonium salts and aliphatic cyclic amines, guanidines, urea derivatives and the like. Examples of these compounds include N, N-benzyldimethylamine, 2- (dimethylaminomethyl) phenol,
2,4,6-tris (dimethylaminomethyl) phenol, tetramethylguanidine, triethanolamine,
N, N'-dimethylpiperazine, 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo [4,4,0 -5-nonene, hexamethylenetetramine, pyridine, picoline, piperidine, pyrrolidine, dimethylcyclohexylamine, dimethylhexylamine, cyclohexylamine, diisobutylamine,
Di-n-butylamine, diphenylamine, N-methylaniline, tri-n-propylamine, tri-n-octylamine, tri-n-butylamine, triphenylamine, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium Examples include iodide, triethylenetetramine, diaminodiphenylmethane, diaminodiphenylether, dicyandiamide, tolylbiguanide, guanylurea, and dimethylurea. Examples of the imidazole compound include imidazole, 2-ethylimidazole, 2-ethyl-4
-Methylimidazole, 2-methylimidazole, 2-
Phenylimidazole, 2-undecylimidazole,
1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 4,5-diphenylimidazole,
2-methylimidazoline, 2-phenylimidazoline,
2-undecylimidazoline, 2-heptadecylimidazoline, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl-4-methylimidazole, 2-ethylimidazoline, 2-phenyl-4-methylimidazoline, benzimidazole, 1-cyanoethylimidazole and the like. Examples of acid anhydrides include:
Examples include phthalic anhydride, hexahydrophthalic anhydride, pyromellitic dianhydride, and benzophenonetetracarboxylic dianhydride. As the organic phosphorus compound, any phosphorus compound having an organic group can be used. For example, hexamethylphosphoric triamide, tri (dichloropropyl) phosphate, tri (chloropropyl) phosphate, triphenyl phosphite,
Examples include trimethyl phosphate, phenylphosphonic acid, triphenylphosphine, tri-n-butylphosphine, diphenylphosphine, and the like. These curing agents are
They can be used alone or in combination. The amount of the curing agent for the halogenated epoxy resin can be used without any particular limitation as long as the curing reaction of the epoxy group can proceed.
It is used in the range of 0.01 to 5.0 equivalents to the mole.

(Curing Accelerator) A curing accelerator may be added to the resin composition used for the cured epoxy resin, if necessary. Typical curing accelerators include tertiary amines and imidazole. And quaternary ammonium salts.

(Polymer Epoxy Polymer) When it is necessary to form a film as an interlayer insulating layer, it is preferable to use a high molecular weight epoxy polymer having a weight average molecular weight of 50,000 or more for the cured epoxy resin. The high-molecular-weight epoxy polymer having a weight-average molecular weight of 50,000 or more is a polymer obtained by alternately copolymerizing a bifunctional epoxy resin and a bifunctional phenol. May be something. As the bifunctional epoxy resin, which is a raw material for synthesizing a high molecular weight epoxy polymer, any compound having two epoxy groups in the molecule can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin,
Bisphenol S type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, diglycidyl etherified bifunctional phenols, diglycidyl etherified bifunctional alcohols, and their halides and hydrogenated products And any molecular weight of these compounds can be used. Even if these compounds are polymerized with each other, it is only necessary to have two epoxy groups in the molecule.Moreover, these compounds can be used in combination of several types, and components other than the bifunctional epoxy resin, Even if it is contained as an impurity, it can be used.
For the bifunctional phenols that are the raw materials for the synthesis of the high molecular weight epoxy polymer, any compound having two phenolic hydroxyl groups can be used, for example,
Monocyclic bifunctional phenols such as hydroquinone, resorcinol, catechol, and polycyclic bifunctional phenols such as bisphenol A, bisphenol F, biphenol, dihydroxydiphenylether, dihydroxydiphenylsulfone, and halides, alkyl-substituted isomers, and isomers thereof are available. Any molecular weight can be used for these compounds. Even if these compounds are polymerized with each other or polymerized with other compounds,
It suffices to have two phenolic hydroxyl groups in the molecule, several of these compounds can be used in combination, and components other than bifunctional phenols can be used even if they are contained as impurities.

(Crosslinking Agent) When a high molecular weight epoxy polymer or an epoxy resin having a hydroxyl group is used, a crosslinking agent which undergoes a crosslinking reaction with the hydroxyl group can be used, and a crosslinking agent containing a halogen is used. You can also.

(Etching solution) The etching solution for the cured epoxy resin used in the present invention is an alkali metal compound,
Amide solvent, alcohol solvent as a component,
Any compound other than these may be added. Examples of the amide solvent include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N, N, N ′, N′-tetramethylurea, 2-Pyrrolidone, N-methyl-2-pyrrolidone, carbamic acid esters and the like can be used. Of these, the use of N, N-dimethylformamide, N, N-dimethylacetamide, and N-methyl-2-pyrrolidone has the effect of swelling the cured epoxy resin, and the solubility of the decomposed product is particularly good. preferable. These solvents can be used in combination, and can also be used in combination with other solvents typified by ketone solvents, ether solvents and the like. Ketone solvents that can be used together include, for example, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone,
Examples include methyl isobutyl ketone, 2-heptanone, 4-heptanone, diisobutyl ketone, and cyclohexanone.
In addition, ether solvents that can be used in combination, for example, dipropyl ether, diisopropyl ether, dibutyl ether, anisole, phenetole, dioxane, tetrahydrofuran, ethylene glycol dimethyl ether,
Examples include ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether. As the alkali metal compound used in the present invention, lithium, sodium, potassium, rubidium, cesium or any other alkali metal compound that can be dissolved in an alcohol-based solvent may be any, for example, lithium, sodium, potassium , Rubidium, cesium and other metals, hydrides, hydroxides, borohydrides, amides, fluorides, chlorides, bromides, iodides, borates, phosphates, carbonates, sulfates, nitrates, organic acids Salts, alcoholates, phenolates and the like. Examples of the alcohol solvent used in the present invention include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, iso-butanol, tert-butanol, 1-pentanol, and 2-pentanol. 3-pentanol, 2-methyl-1-butanol, is
o-pentyl alcohol, tert-pentyl alcohol,
3-methyl-2-butanol, neopentyl alcohol,
1-hexanol, 2-methyl-1-pentanol, 4-methyl-2-pentanol, 2-ethyl-1-butanol, 1-
Heptanol, 2-heptanol, 3-heptanol, cyclohexanol, 1-methylcyclohexanol, 2-
Methylcyclohexanol, 3-methylcyclohexanol, 4-methylcyclohexanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl Ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol, polyethylene glycol (molecular weight 200 to 400), 1,2-propanediol, 1, 3-propanegio Diol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol,
Examples include 2,3-butanediol, 1,5-pentanediol, glycerin, dipropylene glycol and the like. Of these, methanol, ethanol, ethylene glycol,
Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, triethylene glycol, tetraethylene glycol, and polyethylene glycol are particularly preferred because of their high solubility of alkali metal compounds. Some of these solvents can be used in combination. This etching solution contains amide solvents 50 to 9
The alcohol-based solvent is preferably in a range of 0.5 to 49.5% by weight with respect to 9% by weight, and when the concentration of the amide-based solvent is less than 50% by weight, the swelling property of the epoxy cured product can be improved.
When the solubility of the decomposed product is reduced and exceeds 99% by weight, the concentration of the alkali metal compound is consequently reduced, so that the decomposition rate of the cured epoxy resin is reduced. The concentration of the alkali metal compound in the solution is preferably in the range of 0.5% by weight to 40% by weight. When the concentration is less than 0.5% by weight, the decomposition rate of the cured epoxy resin decreases, and when it exceeds 40% by weight. In addition, the alkali metal compound does not completely dissolve in the alcohol solvent. A surfactant or the like can be added to this etching solution.

In addition, in order to adjust the etching rate at the time of etching, the etching solution can be used at any temperature within the range from the freezing point to the boiling point of the solvent. The etching method is performed by immersion in an etching solution, and can be subjected to vibration by ultrasonic waves to increase the etching rate.Also, without immersion in the solution, spraying by spraying or the like can be performed. You can do it too. It is also possible to make a hole in advance with a drill, a laser or the like, and then etch the remaining resin.

[0022]

EXAMPLES Example 1 An epoxy equivalent of 470 and a brominated bisphenol A type epoxy resin having a bromine content of 22% by weight were used with respect to 100 parts by weight.
Methyl ethyl ketone / ethylene glycol monomethyl ether (weight ratio 9/1) of an epoxy resin composition comprising 4 parts by weight of dicyandiamide and 0.5 part by weight of imidazole
The solution was applied to the roughened surface of the copper foil, and the solvent was removed in a dryer at 150 ° C. for 5 minutes to produce an epoxy adhesive film with a copper foil having a thickness of 50 μm. This was applied to one side of the laminate on which the circuit pattern shown in FIG.
The laminate was laminated under the condition of 0 minutes, and the outer layer copper foil on the side of the adhesive film after lamination was etched by copper foil using a resist so as to have a diameter of 0.15 mm so as to overlap the pad portion of the circuit pattern shown in FIG. A hole was made to expose the cured adhesive film. The exposed adhesive film cured product was removed by etching by immersing it in an etching solution heated to 50 ° C. for 1 hour. As an etching solution, a mixed solution of 4% by weight of sodium hydroxide, 80% by weight of N-methyl-2-pyrrolidone and 16% by weight of methanol was prepared. At this time, the etching solution was circulated, and a fluororesin cartridge filter having an average pore diameter of 1.0 μm was arranged in the circulation path, and while filtering the etching solution,
Etching was performed. After the etching, copper plating was applied to connect the inner layer circuit and the outer layer copper foil. The circuit pattern shown in FIG. 1 (b) was formed by copper foil etching using a resist in accordance with the connection hole of the outer layer copper foil on the adhesive film side, and a test piece for a thermal shock test was prepared. went.

Example 2 A thermal shock test was performed under the same conditions as in Example 1 except that a polypropylene cartridge filter having an average particle size of 5.0 μm was used.

Example 3 Based on 100 parts by weight of a brominated bisphenol A type epoxy resin having an epoxy equivalent of 400 and a bromine content of 48% by weight,
A thermal shock test was conducted under the same conditions as in Example 1 except that an epoxy resin composition comprising 30 parts by weight of phenol novolak resin and 0.2 parts by weight of imidazole was used, and a stainless steel cartridge filter having an average pore diameter of 3.0 μm was used. Was done.

Example 4 A thermal shock test was performed under the same conditions as in Example 3 except that a polyester cartridge filter having an average pore diameter of 25.0 μm was used.

Example 5 20 parts by weight of phenol-masked diisocyanate and tetrabromobisphenol A were added to 100 parts by weight of a high-molecular-weight epoxy polymer having a weight-average molecular weight of 100,000 synthesized from bisphenol A type epoxy resin and bisphenol A. A thermal shock test was performed under the same conditions as in Example 1 except that a resin composition composed of 30 parts by weight of the epoxy resin was used.

Example 6 A weight-average molecular weight of 130,00 synthesized from a bisphenol A epoxy resin and tetrabromobisphenol A
Using a resin composition comprising 20 parts by weight of diisocyanate masked with methyl ethyl ketone oxime, 30 parts by weight of a bisphenol A type epoxy resin, and 20 parts by weight of talc as a filler, based on 100 parts by weight of a high molecular weight epoxy polymer having a molecular weight of 0 Example 1 was repeated except that filtration was carried out using a stainless steel cartridge filter having a pore size of 40.0 μm.
A thermal shock test was performed under the same conditions as described above.

Example 7 As an etching solution, potassium hydroxide 5% by weight, N, N
A thermal shock test was performed under the same conditions as in Example 1 except that a mixed solution of 75% by weight of dimethylformamide and 20% by weight of ethylene glycol was used.

Example 8 A thermal shock test was performed under the same conditions as in Example 3 except that the etching solution prepared in Example 7 was used.

Example 9 A thermal shock test was performed under the same conditions as in Example 5 except that the etching solution prepared in Example 7 was used.

Example 10 As an etching solution, 5% by weight of lithium hydride, N, N
A thermal shock test was performed under the same conditions as in Example 1 except that a mixed solution of 70% by weight of dimethylacetamide and 25% by weight of ethylene glycol monomethyl ether was used.

Example 11 A thermal shock test was performed under the same conditions as in Example 3 except that the etching solution prepared in Example 10 was used.

Example 12 A thermal shock test was performed under the same conditions as in Example 6 except that the etching solution prepared in Example 10 was used.

Comparative Example 1 The procedure of Example 1 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 2 The procedure of Example 3 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 3 The procedure of Example 5 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 4 Example 6 was the same as Example 6 except that etching was performed without filtering with a filter.

Comparative Example 5 Example 7 was the same as Example 7 except that etching was performed without filtering with a filter.

Comparative Example 6 The procedure of Example 8 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 7 The procedure of Example 9 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 8 The procedure of Example 10 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 9 The procedure of Example 11 was repeated, except that the etching was performed without filtering with a filter.

Comparative Example 10 Example 12 was the same as Example 12 except that etching was performed without filtering with a filter.

(Test Method) In each of the examples and comparative examples, etching for producing a test piece for a thermal shock test was performed 100 times, and the first, tenth, 25th, 50th, and
A thermal shock test was performed for each of the 00th times. The circuit patterns used in the examples and comparative examples were those shown in FIGS. 1A and 1B, and had a pad diameter of 0.30 mm and a conductor width of 0.15 mm. The conditions and test method of the thermal shock test are shown below. Step 1 temperature / time: -65 ± 3 ° C / 30 minutes Step 2 temperature / time: 175 ± 3 ° C / 30 minutes Steps 1 and 2 are performed once each to make one cycle, and the connection between the inner and outer layers is established. The number of cycles that were not performed and were not judged to be broken and had no practical problem was set to 30 cycles.
Table 1 shows the results of Examples and Comparative Examples.

[0045]

[Table 1]

In Comparative Examples 1 to 10, the number of etchings was 25, the thermal shock test was reduced to 15 to 25 cycles, which did not satisfy 30 cycles which would not be a problem in practical use. While etching could not be carried out until reaching, and the connection between the inner layer circuit and the outer layer circuit could not be made after plating, Examples 1 to 12 showed that the thermal shock test was 30 cycles or more even at the 100th etching, and the connection reliability was high. It has been found that it is possible to form a hole for interlayer connection having good properties. According to the present invention, in a manufacturing process of a multilayer wiring board using an epoxy resin cured product containing a halogen atom as an insulating layer, an etching solution comprising an alkali metal compound, an amide solvent, and an alcohol solvent is circulated for etching. By using the filter and arranging a filter in the circulation path and filtering the etchant, the productivity and the quality of the hole for interlayer connection could be improved.

[0047]

As described above, according to the present invention, it is possible to provide a method for manufacturing a multilayer printed wiring board having excellent etching accuracy and having holes for interlayer connection.

[Brief description of the drawings]

FIG. 1A is a top view showing a circuit pattern of an inner layer of a test piece used in one embodiment of the present invention, and FIG. 1B is a top view showing a circuit pattern of an outer layer.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/00 H05K 3/00 K (72) Inventor Katsushi Shibata 1500 Ogawa Ogawa, Shimodate City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Within Shimodate Research Institute Co., Ltd. DC38 DC41 DC46 DD07 FB07 JA08 5E346 CC09 CC55 GG15 GG22

Claims (9)

[Claims] 1. A method of manufacturing a multilayer printed wiring board using an epoxy resin cured product containing a halogen atom for an insulating layer, wherein a hole for interlayer connection is formed using an alkali-cured resin cured product. A method for producing a multilayer printed wiring board, wherein the method is a method of removing with an etching solution comprising a metal compound, an amide-based solvent, and an alcohol-based solvent, and wherein the treatment is performed while filtering the etching solution. 2. The method for producing a multilayer printed wiring board according to claim 1, wherein a cured epoxy resin having a halogen atom content of 5 wt% or more is used for the insulating layer. 3. The multilayer printed wiring according to claim 1, wherein a cured product of a halogenated polyfunctional epoxy resin and / or a cured product of a halogenated polyfunctional phenol are used as the cured epoxy resin. Plate manufacturing method. 4. The cured epoxy resin has a weight average molecular weight of 5
The method for producing a multilayer printed wiring board according to any one of claims 1 to 3, wherein a high molecular weight epoxy polymer having a molecular weight of 000 or more is used. 5. A high-molecular-weight epoxy polymer having a weight-average molecular weight of 50,000 or more using a halogenated difunctional epoxy resin and / or a halogenated bifunctional phenol as a raw material for the cured epoxy resin. A method for manufacturing a multilayer printed wiring board according to claim 1. . 6. The method for producing a multilayer printed wiring board according to claim 1, wherein a bromine atom is used as the halogen atom. 7. An amide solvent of an etching solution containing N, N-
7. A method according to claim 1, wherein at least one selected from the group consisting of dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone is used.
The method for producing a multilayer printed wiring board according to any one of the above. 8. An alcoholic solvent for an etching solution comprising methanol, ethanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, triethylene glycol, tetraethylene glycol, and polyethylene glycol. The method for manufacturing a multilayer printed wiring board according to any one of claims 1 to 7, wherein at least one selected from a group is used. 9. An amide solvent having a concentration of 50 to 99.
The multilayer print according to any one of claims 1 to 8, wherein a composition comprising 0.5% to 49.5% by weight of an alcohol solvent and 0.5% to 40% by weight of an alkali metal compound is used. Manufacturing method of wiring board.