JP2003051657A - Method for manufacturing printed circuit substrate having ultra fine wiring pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high-density printed circuit substrate in which a pattern having proper copper foil adhesive force and a good shape is manufactured of ultra fine wirings on a thin copper foil-clad copper-clad substrate. SOLUTION: A method for manufacturing a printed circuit substrate, having the ultra fine wiring pattern comprises the steps of applying electroless copper plating of 0.1 to 1 μm and then electric copper plating of 0.5 to 3 μm by using an ultra thin copper foil (a), having a copper foil thickness of 5 μm or less of an outermost layer formed with a through-hole and/or a blind via hole, adhering a plating resist (h), then making electric copper plating of 6 to 30 μm to adhere, further making adhering plating resist (j) thereon, making nickel plating and gold plating or solder plating to adhere at a position in which the plating resist is not adhered, peeling off the resist, and then melt removing a thin electrical copper plating layer (g), an electroless copper plating layer (f) and the ultra fine copper foil layer by etching to form a pattern of line/space = 40/40 μm or less. Accordingly, the high-density printed circuit substrate having the very small undercut of the pattern and superior copper foil adhering force can be obtained.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a printed wiring board having an extremely fine line / space pattern, for example, a pattern of 40/40 μm or less. The high-density printed wiring board having the obtained ultrafine line pattern is mainly used for a new semiconductor plastic package or the like. 2. Description of the Related Art Conventionally, in a high-density printed wiring board used for a semiconductor plastic package or the like, a method of forming a fine line pattern is 5 μm by a subtractive method.
Using the following ultra-thin copper foil, after forming through holes and / or blind via holes with a carbon dioxide laser, etc.,
Deposit about 15μm and remove the copper foil by etching using a plating resist, etc., or irradiate the carbon dioxide laser directly on the copper foil to remove the copper foil burrs generated in the holes after the formation of through holes and / or blind via holes. 12μ the surface layer of the copper foil and simultaneously dissolved and removed by SUEP (S urface U niform E tching P rocess)
A method of dissolving and removing from a thickness of 5 m or less to a thickness of 5 μm or less, and after desmearing, depositing a copper plating of about 15 μm and using a normal etching resist or the like to form a fine line pattern is known. In this method, the pattern becomes thinner than the bottom by etching, and the cross section becomes trapezoidal or triangular, which has caused a defect. There is also a method of producing a fine line pattern using an etching resist or the like after plating up by a semi-additive method. However, this method is also required when the thickness of copper plating is increased to about 18 μm. It has the same shape, and has problems in adhesion to copper, reliability and the like. Further, when copper plating is applied by the full additive method, there is a problem that even if the copper plating layer is thickened, the adhesive strength of copper is low. On the other hand, using an ultra-thin copper foil, applying electroless copper plating on this, then forming a pattern by the pattern copper plating method, and furthermore, applying a thin electroless copper layer on the substrate by the semi-additive method There is a method of forming a pattern by a pattern copper plating method using this, but the electroless copper layer is side-etched in the final flash etching, and there is a problem with copper adhesion in a fine pattern. . Further, the fine pattern has a problem in reliability such as migration resistance. [0004] The present invention has solved the above-mentioned problems by a subtractive method, that is, an ultrafine line pattern having a good pattern shape while maintaining the adhesive strength of a copper foil. It is intended to provide a method for manufacturing a printed wiring board on which is formed. SUMMARY OF THE INVENTION The present invention provides a high-density printed circuit having an extremely fine line pattern and excellent copper foil adhesion by manufacturing a printed wiring board in the following steps. A wiring board was obtained. That is, (1) a through-hole and / or a blind via hole is formed, the outermost copper foil thickness is 5 μm or less using an ultra-thin copper-clad plate, and the surface including the inside of the hole is 0.1 mm.
Electroless copper plating of 1 to 1 μm is applied, (2) Then, an electrolytic copper plating layer having a thickness of 0.5 to 3 μm is formed using the electroless copper plating deposition layer as an electrode, and (3) the copper plating deposition layer Form a plating resist layer for pattern electroplating on the required part on the top, (4) On the copper surface where the plating resist layer is not formed,
Attach 6-30μm of pattern copper plating by electrolytic copper plating,
(5) Attach plating resist on it, (6) Attach nickel plating and gold plating, or solder plating, (7)
(8) Etch the entire surface, dissolve and remove the thin copper layer, electroless copper layer and ultra-thin copper foil layer at least where the pattern copper plating layer is not formed. A printed wiring board having a pattern is manufactured. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention uses a copper-clad board laminated using a general thin copper foil of 5 μm or less, and has a line / space of 40/40 μm or less, and further 25/25 μm or less. A high-density printed wiring board is manufactured by the method of manufacturing a fine line pattern described above. The process is as follows: (1) First, an ultrathin copper-clad board having at least two or more layers of copper foil, in which a general electrolytic copper foil of 5 μm or less is provided on the outermost layer. Through holes and / or blind via holes are formed in the ultra-thin copper-clad plate by a generally known method. There is no particular limitation on the method of producing the ultra-thin copper foil clad laminate having a copper foil thickness of 5 μm or less as the outermost layer. Peeling off to make a copper-clad board, lamination molding using a copper foil with a thickness exceeding 5 μm, and removing it by etching before drilling
5μm or less, or carbon dioxide laser JP 11-22024
3.As shown in JP-A-11-346059, after drilling, the copper foil burr generated around the hole is removed by etching, and at the same time, a part of the copper foil in the thickness direction is removed by etching to leave a residual copper foil thickness of 5 μm.
A generally known method such as the following method can be used. An electroless copper plating of 0.1 to 1 μm is applied to the surface including the inside of the hole of the copper clad plate having the hole. (2) Next, an electrolytic copper plating layer having a thickness of 0.5 to 3 μm is formed using the electroless copper plating deposited layer as an electrode.
The type of copper plating is not particularly limited, and for example, copper sulfate plating, copper pyrophosphate plating, or the like can be used. (3) A plating resist layer for copper electroplating is formed on required portions of the copper plating deposition layer. This step is also performed by a generally known method. If the degree of curing of the plating resist by UV irradiation is insufficient, the degree of curing is improved by post-UV irradiation or post-heat curing so that the plating resist does not swell in the subsequent electroplating. (4) On the copper surface on which the plating resist layer is not formed, pattern copper plating is performed by electrolytic copper plating to 6 to 30 μm,
Preferably, 10 to 20 μm is deposited, (5) a plating resist is deposited thereon, (6) nickel plating and gold plating, or solder plating is deposited where necessary, (7) the plating resist is peeled off, (8) etching the entire surface, dissolving and removing at least the thin copper layer, the electroless copper layer and the ultra-thin copper foil layer at the portion where the pattern copper plating layer is not formed to form a printed wiring board having an ultra-fine line pattern To manufacture. By producing a fine pattern in this step, a pattern having a good shape could be formed without undercut as compared with a normal method, and a printed wiring board excellent in reliability could be manufactured. [0010] The copper-clad board used in the present invention is a copper-clad board having two or more layers of copper. Copper clad laminate,
Examples thereof include a multilayer copper-clad board having a generally known structure, such as a multilayer copper-clad board, a multilayer board using a copper foil sheet with a resin as a surface layer, and a copper-clad board of a base material such as a polyimide film or a polyparabanic acid film. The substrate-reinforced copper-clad laminate is first impregnated with a thermosetting resin composition and dried to form a B stage,
Create a prepreg. Next, a predetermined number of the prepregs are stacked, and a copper foil having a thickness of 3 to 5 μm for reinforcing a protective metal plate is arranged outside the prepreg, and laminated under heat and pressure to form a copper-clad laminate. The multilayer board is formed by processing the copper foil of the double-sided copper-clad laminate to form a pattern, treating the copper foil surface to produce an inner layer board,
Place the prepreg and B-stage resin sheet on the outside, place the protective metal plate reinforced thin copper foil on the outside, and laminate or form the B-stage resin sheet with the protective metal plate reinforced thin copper foil on the outside of the inner layer plate. And laminated to form a multilayer copper-clad board. Also, as the outermost layer of double-sided copper clad board and multilayer copper clad board
It is also possible to form a laminate using a copper foil of 7 μm or more, and to etch the copper foil to a thickness of 5 μm or less. In this case, it is also possible to perform etching so as to leave only the feet (knobs) of the copper foil. As the substrate, generally known organic and inorganic woven fabrics and nonwoven fabrics can be used. Specifically, examples of the inorganic fibers include fibers such as E, S, D, and NE glass. Examples of the organic fibers include generally known fibers such as wholly aromatic polyamide and liquid crystal polyester. These may be mixed. In addition, a film substrate is also used. As the resin of the thermosetting resin composition used in the present invention, generally known thermosetting resins are used.
Specifically, an epoxy resin, a polyfunctional cyanate ester resin, a polyfunctional maleimide-cyanate ester resin, a polyfunctional maleimide resin, an unsaturated group-containing polyphenylene ether resin, and the like, and one or more kinds Are used in combination. From the viewpoint of through-hole shape in processing by high-output carbon dioxide laser irradiation, a thermosetting resin composition having a glass transition temperature of 150 ° C or higher is preferable, and has moisture resistance, migration resistance, and electrical characteristics after moisture absorption. In view of the above, a polyfunctional cyanate resin composition is preferred. When the through hole and / or the blind via hole are formed by a carbon dioxide gas laser, a nickel metal, a cobalt metal, a nickel metal, a cobalt metal, or the like may be formed on the shiny surface of the copper foil in addition to the methods described in JP-A-11-220243 and JP-A-11-346059. Using a copper foil that has been subjected to an alloy treatment, a method of irradiating a carbon dioxide gas laser directly onto the copper foil to form holes, or on a copper foil that has been subjected to black copper oxide treatment, chemical treatment, etc. For example, a method of directly irradiating a carbon dioxide laser on the copper foil to form a hole can be used. The copper foil adhered to the protective metal plate used in the present invention is generally known. The thickness of the copper foil is
3-5μm, untreated on the shiny side of copper foil,
Alternatively, a nickel metal, a cobalt metal, or an alloy thereof is used. If metal treatment is applied, copper foil is laminated on the surface and stretched, and after removing the protective metal plate on the surface, relatively low energy 5-20m directly from above
The hole can be formed by irradiating the carbon dioxide laser of J. or,
A thin nickel foil can be used instead of the thin copper foil. When drilling through holes and / or blind via holes, a copper-clad board is prepared by using a copper foil exceeding 5 μm for the surface layer, and the copper foil on the surface layer is dissolved to 5 μm or less with a chemical solution and directly A method in which a copper foil is processed by irradiating a gas laser to form through holes and / or blind via holes can also be used.
A method of drilling through holes using a metal drill of 100 to 150 μm can also be used. A carbon dioxide laser is irradiated by pulse oscillation at an output of 5 to 60 mJ to form a through hole and / or
Alternatively, when a blind via hole is formed, burrs are generated around the hole. Therefore, after the carbon dioxide laser irradiation, both surfaces of the copper foil are planarly etched in the thickness direction, preferably with a chemical solution, and by removing a part of the thickness of the original metal foil, burrs are simultaneously formed. The removed and obtained thinned copper foil is suitable for forming a fine pattern, and forms a through hole and / or a blind via hole in which the copper foil around the hole suitable for a high-density printed wiring board remains. . In the case of removing burrs, etching is more preferable than mechanical polishing in terms of removing burrs from holes and dimensional change due to polishing. The method of the present invention for removing the copper burrs generated in the holes and part of the copper foil in the thickness direction by etching is as follows.
Although not particularly limited, for example, JP-A-02-22887, JP-A-02-228
96, 02-25089, 02-25090, 02-59337, 02-6018
9, 02-166789, 03-25995, 03-60183, 03-9449
1, a method of dissolving and removing a metal surface with a chemical (referred to as a SUEP method) disclosed in JP-A-04-199592 and JP-A-04-263488. The etching rate is 0.02 to 1.0 μm / sec. The carbon dioxide laser is in the infrared wavelength range.
Wavelengths between 9.3 and 10.6 μm are commonly used. Energy is
The copper foil is processed by pulse oscillation at 5 to 60 mJ, preferably 7 to 45 mJ, and holes are made. Energy is processed on the surface copper foil,
It is appropriately selected according to the thickness of the copper foil. Of course, hole formation with an excimer laser or a YAG laser can be used or used together. After the entire surface is finally electroplated with copper, the thin copper layer is etched until it reaches the substrate to form a pattern. The etchant is not particularly limited, and a generally known method such as the above-mentioned SUEP method, a method using a ferric chloride, copper chloride, or ammonium persulfate solution can be used, but the SUEP method is preferably used. The present invention will be specifically described below with reference to examples and comparative examples. Unless otherwise specified, “parts” indicates parts by weight. Example 1 900 parts of 2,2-bis (4-cyanatophenyl) propane,
100 parts of (maleimidophenyl) methane are melted at 150 ° C,
The mixture was reacted for 4 hours with stirring to obtain a prepolymer. This was dissolved in a mixed solvent of methyl ethyl ketone and dimethylformamide. Add bisphenol A type epoxy resin (trade name: Epicoat 1001, Yuka Shell Epoxy Co., Ltd.)
) And 600 parts of a cresol novolak type epoxy resin (trade name: ESCN-220F, manufactured by Sumitomo Chemical Co., Ltd.) were uniformly mixed and dissolved. Further, as a catalyst, zinc octylate 0.4
Was added and dissolved and mixed. To this, 2000 parts of an inorganic filler (trade name: calcined talc, manufactured by Nippon Talc Co., Ltd.) was added, and the mixture was uniformly stirred and mixed to obtain Varnish A. This varnish is impregnated with a glass woven fabric having a thickness of 100 μm, dried at 150 ° C., and subjected to a gelation time (at 170
C) for 120 seconds to prepare a prepreg (prepreg B) having a thermosetting resin composition content of 44% by weight. A general electrolytic copper foil having a thickness of 12 μm is arranged above and below the four prepregs B, and 200
The laminate was subjected to lamination molding under a vacuum of 20 ° C., 20 kgf / cm ² and 30 mmHg for 2 hours to obtain a double-sided copper-clad laminate C having an insulating layer thickness of 400 μm. On the other hand, copper powder (average particle diameter: 0.
8 μm) of 800 parts was added to a varnish prepared by dissolving polyvinyl alcohol powder in water, and uniformly mixed by stirring (varnish D).
This was coated on one side of a 25 μm-thick polyethylene terephthalate film to a thickness of 60 μm,
After drying for 0 minutes, an auxiliary material E having a metal powder content of 65% by volume was formed. A varnish D was applied to one side of a 50 μm-thick aluminum so as to have a resin layer thickness of 30 μm, and dried to prepare a backup sheet F. The copper clad laminate C
An auxiliary material E is placed on top, and a backup sheet F is placed below, with the resin surface facing the copper foil side, and laminated with a roll at a temperature of 100 ° C. at a linear pressure of 15 kgf / cm to obtain good adhesion. A coating was formed. 900 holes with a hole diameter of 1 μm and a diameter of 100 μm are directly irradiated with a direct carbon dioxide laser at a pulse energy of 30 m from above.
Irradiation was performed with J for 6 shots, and 70 blocks of through holes were made. After the desmear treatment, the copper foil burrs around the hole are dissolved and removed by the SUEP method, and the copper foil on the surface is also 2 μm.
Until dissolved. An electroless copper plating was applied to the plate at a thickness of 0.4 μm, and then a copper layer having a thickness of 1 μm was applied by electrolytic copper plating. A resist layer for pattern copper electroplating was formed to a thickness of 18 μm on a required portion on the copper plating deposition layer, and a pattern copper plating of 15 μm was applied to the copper surface of the portion where the plating resist was not formed by copper electroplating. A plating resist of 10 μm is further adhered on this, and nickel plating is
m, after depositing gold plating 0.5μm on it, stripping off all plating resist, etching the whole surface with SUEP solution (flash etching), line / space = 25 / 25μ
m pattern was formed. This pattern cross section had a good shape without undercut due to etching.
A UV permanent protection resist was applied thereon and cured by a conventional method except for a portion where gold plating was adhered. Table 1 shows the evaluation results of the printed wiring board. Example 2 Epoxy resin (trade name: Epicoat 5045) 700 parts, epoxy resin (trade name: ESCN220F) 300 parts, dicyandiamide 35
And 1 part of 2-ethyl-4-methylimidazole was dissolved in a mixed solvent of methyl ethyl ketone and dimethylformamide. 800 parts of the calcined talc of Example 1 was further added, and the mixture was uniformly dispersed by forced stirring to obtain Varnish G. . This is impregnated into a 100 μm thick glass woven fabric, dried, and impregnated into a prepreg (prepreg H) having a gelling time of 150 seconds, a thermosetting resin composition content of 45% by weight and a 50 μm thick glass woven fabric, After drying, a prepreg (prepreg I) having a gelling time of 178 seconds and a thermosetting resin composition content of 70% by weight was prepared. Using two sheets of this prepreg H, a general electrolytic copper foil having a thickness of 12 μm is placed on both sides, and laminated and molded at 190 ° C., 20 kgf / cm ² , and a vacuum of 30 mmHg or less for 2 hours to form a double-sided copper-clad laminate J. Produced. A pattern is formed on both surfaces, black copper oxide treatment is performed, and one prepreg I is disposed on both outer sides, and a thickness of 3
A copper foil (product name: F3B-WS copper foil, Furukawa Circuit Foil) that is treated with a cobalt alloy on the shiny surface of a general electrolytic copper foil of μm, and overlaid with a protective and reinforced 35 μm copper plate
Co., Ltd.) was arranged and laminated and molded in the same manner to produce a four-layer plate. Peel off the protective metal plate on this surface, and on the copper foil on the surface,
One shot was irradiated with a carbon dioxide laser pulse energy of 12 mJ, and blind via holes with a hole diameter of 100 μm were made on both sides.
Put this in a plasma device, remove the residual resin at the bottom, dissolve and remove the surface cobalt alloy treatment with a chemical solution to make the copper foil thickness 1 μm, and then electroless copper plating with a thickness of 0.3 μm on the whole. After applying a 2μm-thick electrolytic copper plating, a plating resist for electrolytic copper plating is adhered to 15μm, and an electrolytic copper plating is applied to the copper surface on which the plating resist layer is not formed.
14 μm was attached. Further, a plating resist is deposited thereon, and solder plating is deposited to a thickness of 10 μm. Then, the plating resist is peeled off, and the entire surface is etched to obtain a thin copper layer where the pattern copper plating layer and the solder plating layer are not formed. The layer, the electroless copper layer, and the ultra-thin copper foil layer were dissolved and removed up to the substrate to produce a printed wiring board having line / space = 20/20 μm. The printed wiring board was covered with a UV permanent protection resist except for the portions where solder plating was applied by a standard method (FIG. 1). Table 1 shows the evaluation results. COMPARATIVE EXAMPLE 1 In the production of the printed wiring board of Example 2, copper plating was applied only to the electroless copper plating by 4 μm, and the panel electrolytic copper plating was directly applied on the electroless copper plating without applying the subsequent electrolytic copper plating. gave. This was similarly etched to remove the thin electroless copper layer and the ultra-thin copper foil layer to which the pattern copper plating was not adhered, to obtain a printed wiring board. The underside of this pattern had an undercut of 6.1 μm on both sides. Table 1 shows the evaluation results. Comparative Example 2 A 12 μm general electrolytic copper foil was applied to the surface of the four-layer copper-clad laminate of Example 2 instead of a copper foil with a metal plate on the surface layer.
Etching was performed down to μm to form 1 μm irregularities on the surface.
Place this on an XY table, irradiate one shot of 15mJ carbon dioxide laser pulse energy from the surface to make a blind via hole, similarly apply plasma treatment, apply 1μm of electroless copper plating, and attach 14μm of electrolytic copper plating After depositing an etching resist of 20 μm thereon, a pattern of line / space = 20/20 μm was formed by a conventional method, but the shape was triangular and the shape was not good. Table 1 shows the evaluation results. Comparative Example 3 After removing the copper foil on the surface layer of the copper-clad laminate of Example 1 by etching, a through hole having a hole diameter of 100 μm was made with a carbon dioxide gas laser of 15 mJ, and the surface was desmeared to perform electroless copper plating. 0.9
μm, and electrolytic copper plating was adhered thereon to 16 μm.
This is performed in the same manner as in Comparative Example 2, and the line / space is 20 / 20μ.
m pattern was formed. This had an undercut, the shape was triangular, and the shape was poor. Table 1 shows the evaluation results. Comparative Example 4 In Example 2, acrylonitrile butadiene rubber (trade name: N210S, JSR <
Co., Ltd.) was added, and the mixture was uniformly stirred and mixed. Then, a prepreg was prepared in the same manner, and laminated and formed into a four-layer plate. After etching and removing the copper foil on the surface layer of this multilayer copper clad board, a blind via hole with a hole diameter of 100 μm is made with a carbon dioxide gas laser 15 mJ, the surface is desmeared, the entire surface is electroless copper plated 1 μm, and the electrolytic copper plating is performed. A resist was adhered, and an electrolytic copper plating was applied to a thickness of 16 μm on the electroless copper plating where no plating resist was attached. After stripping the plating resist, the entire surface was etched to dissolve and remove the thin electroless copper plating layer to form a line / space = 20/20 μm pattern. This had a little undercut. Table 1 shows the evaluation results. (Table 1) Item Example Comparative Example 1 2 1 2 3 4 Ant-cut (μm) <1 <1 6.1 <1 3.3 1.9 Polyester cross-sectional shape Good Good Bad Triangular Triangular Almost good Copper foil adhesion (kgf / cm) 1.35 1.17 0.61 0.90 0.43 0.77 Ca Bu glass transition temperature (℃) 235 160 235 160 235 154 migration resistance normal ^{5x10 14 6x10 14 5x10 14 4x10 14} 5x10 14 5x10 14 200hrs. 3x10 11 4x10 8 2x10 11 2x10 8 4x10 11 < ^{. 1x10 8 500hrs 6x10 10 <1x10} 8 5x10 10 <1x10 8 5x10 10 over [0029] <measurement method> 1) undercut and a pattern cross-sectional shape: a pattern section was 100 observed and expressed as mean values. For the design value,
The etched distance on one side is shown. The shape was also observed. 2) Copper foil adhesion: Measured according to JIS C6481. The width was measured by the pattern width and converted to kgf / cm and displayed. 3) Glass transition temperature: Measured according to the DMA method of JIS C6481. 4) Migration resistance: In each of Examples and Comparative Examples, a thermosetting resist (trade name:
BT-M450 (Mitsubishi Gas Chemical Co., Ltd.) was coated to a thickness of 40 μm, cured, and applied at 85 ° C./85% RH / 50 VDC to measure the insulation resistance between the patterns. According to the method for producing an ultrafine wire pattern on a copper-clad board having at least two or more thin copper layers on its outer layer, having through holes and / or blind via holes, After applying electroless copper plating and electro copper plating, apply a plating resist and perform pattern copper plating, then attach nickel plating and gold plating, or plating resist to places other than where solder plating is applied, nickel plating and gold plating Alternatively, by applying solder plating and stripping the plating resist, the thin electric copper layer, the electroless copper layer and the thin copper layer were removed by etching, whereby a good pattern having a shape with very few undercuts could be produced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a thin line forming step of Example 1. FIG. 2 is a view showing a thin line forming process of Comparative Example 1. FIG. 3 is a view showing a thin line forming process of Comparative Example 2. [Description of Signs] a Electrolytic thin copper foil with surface cobalt alloy layer formed b Inner layer copper foil c Insulating layer d Blind via hole drilled by carbon dioxide laser e Electrolytic copper foil with surface etched f Electroless copper plating Layer g Electroplated copper layer h Plating resist i Electroplated copper formed by panel plating j Solder plating resist k Solder plating l Thin copper foil layer part m removed by etching m Fine pattern formed by flash etching n Permanent protection solder Resist

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/24 H05K 3/24 B 3/42 620 3/42 620A 3/46 3/46 GN (72 ) Inventor Katsuji Komatsu 6-1-1, Shinjuku, Katsushika-ku, Tokyo F-term in Tokyo Plant of Mitsubishi Gas Chemical Co., Ltd. AD05 AE01 BC02 BD02 BD03 BD06 BD08 BD11 BE13 CD05 CD06 CE02 CE13 CE17 DD03 FF02 GG02 5E343 AA12 AA17 BB08 BB18 BB23 BB24 BB34 BB44 BB54 BB61 BB67 BB71 CC61 CC67 DD33 DD43 DD76 ER11 CC18 CCA CCA CC CC CC55 DD02 DD25 DD32 EE02 EE06 EE09 EE13 FF15 GG17 GG22 GG25 HH07 HH11

Claims (1)

Claims (1) (1) Using an ultra-thin copper foil clad board having a through-hole and / or a blind via hole and having an outermost copper foil thickness of 5 μm or less, A surface containing 0.1 to 1 μm of electroless copper plating is applied, (2) Then, a 0.5 to 3 μm thick electrolytic copper plating layer is formed on the electroless copper plating deposition layer, and (3) the copper plating A plating resist layer for pattern electroplating is formed on the required portion on the deposited layer, and (4) a pattern copper plating is adhered to the copper surface on which the plating resist layer is not formed by 6 to 30 μm by electrocopper plating, 5) Attach plating resist on it, (6) Attach nickel plating and gold plating, or solder plating, (7) Peel and remove plating resist, (8) Etch entire surface, at least pattern copper plating layer Of the thin copper layer, electroless copper layer and ultra-thin copper foil layer A method for producing a printed wiring board having an ultrafine line pattern, which is produced by dissolving and removing.