JP2849059B2 - Processing method of copper foil for printed circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a copper foil for a printed circuit, and more particularly to a method for treating a copper foil on a surface of the copper foil.
After roughening treatment by cobalt-nickel alloy plating, by forming a cobalt-nickel alloy plating layer, it has alkali etching property, and has good heat-resistant peeling strength and heat-resistant oxidation property, and has a black surface tone. The present invention relates to a method for producing a copper foil for a printed circuit, which further improves the heat-resistant oxidation resistance by forming a zinc-nickel alloy plating layer. The copper foil of the present invention can be used, for example, for fine pattern printed circuits and FPCs (Flexible Printe) for magnetic heads.
d Circuit).

[0002]

2. Description of the Related Art Copper and copper alloy foil (hereinafter referred to as copper foil)
Has greatly contributed to the development of the electrical and electronic related industries,
In particular, it is indispensable as a printed circuit material. In general, copper foil for printed circuits is laminated and bonded to a base material such as a synthetic resin board and a film under a high temperature and a high pressure with an adhesive or without using an adhesive to produce a copper-clad laminate. After a necessary circuit is printed through a resist coating and exposure process to form a circuit to be formed, an etching process for removing an unnecessary portion is performed. Finally, the required elements are soldered to form various printed circuit boards for electronic devices. The quality requirements for the copper foil for printed circuit boards differ between the surface to be bonded to the resin substrate (roughened surface) and the non-bonded surface (glossy surface), and many methods have been proposed for each.

[0003] For example, requirements for a roughened surface include mainly that there is no oxidative discoloration during storage and that the peeling strength with a substrate is sufficient even after high-temperature heating, wet processing, soldering, chemical processing, or the like. And that there is no so-called lamination stain generated after lamination with the base material and etching.

[0004] Roughening plays a large role in determining the adhesion between the copper foil and the substrate. As the roughening treatment, copper roughening treatment for electrodepositing copper was initially adopted, but various techniques have been subsequently proposed, especially heat-resistant peel strength,
Copper-nickel roughening treatment has come to be established as one typical treatment method for the purpose of improving hydrochloric acid resistance and oxidation resistance. The present applicant has proposed copper-nickel roughening treatment in Japanese Patent Application Laid-Open No. 52-145768 and has achieved results. The copper-nickel-treated surface has a black color, and particularly in rolled foils for flexible substrates, the black color of the copper-nickel treatment has been recognized as a symbol as a commercial product.

However, the copper-nickel roughening treatment is
Although excellent in heat-resistant peeling strength, oxidation resistance and hydrochloric acid resistance, it is difficult to etch with an alkaline etchant that has recently become important as a fine pattern treatment.
When a fine pattern having a circuit width of 150 μm or less is formed, the processing layer is left unetched.

Therefore, as a process for fine patterns,
The applicant of the present application has previously conducted Cu-Co treatment (Japanese Patent Publication No. 63-21 / 1988)
No. 58 and Japanese Patent Application No. 1-112227) and Cu-Co
-Ni processing (Japanese Patent Application No. 1-112226) was developed.
These roughening treatments had good etching properties, alkali etching properties and hydrochloric acid resistance, but it was found again that the heat-resistant peel strength when using an acrylic adhesive was reduced, and oxidation resistance was also low. The color was not enough and the color did not reach black, but it was brown to dark brown.

[0007] With the recent trend toward fine patterning and diversification of printed circuits, the printed circuit boards have heat-resistant peel strength (especially when an acrylic adhesive is used) and hydrochloric acid resistance comparable to those of Cu-Ni treatment. A printed circuit having a circuit width of 150 μm or less can be etched with an alkaline etchant. Oxidation resistance (180 ° C.) as in the case of Cu-Ni treatment.
It has been further required to improve the oxidation resistance in an oven for 30 minutes, and to perform the same blackening treatment as in the case of Cu-Ni treatment. That is, as the circuit becomes thinner, the tendency of the circuit to be easily peeled off by the hydrochloric acid etching solution becomes stronger, and it is necessary to prevent such tendency. When the circuit becomes thin,
The high temperature during the processing such as soldering also makes the circuit easy to peel off, and its prevention is also necessary. Currently fine pattern progresses, for example in CuCl ₂ etching solution 150
It is no longer an essential requirement that a printed circuit having a circuit width of μm pitch or less can be etched, and alkali etching is becoming a necessary requirement as resists and the like are diversified.
The black surface is also important from the standpoint of copper foil fabrication and chip mounting in terms of enhancing alignment accuracy and heat absorption.

In response to such a demand, the applicant of the present application has proposed a method of forming a printed circuit by forming a cobalt plating layer or a cobalt-nickel alloy plating layer on a surface of a copper foil after roughening treatment by copper-cobalt-nickel alloy plating. As well as having many of the above-mentioned general properties as a copper foil, in particular, it has the above-mentioned properties comparable to Cu-Ni treatment, and furthermore, has a reduced heat-resistant peel strength when an acrylic adhesive is used. Without this, the inventors succeeded in developing a copper foil treatment method having excellent oxidation resistance and a black surface color (Japanese Patent Publication No. 6-54831). The cobalt-nickel alloy plating layer is more excellent in heat deterioration resistance than the cobalt plating layer.
Preferably, after forming the cobalt plating layer or the cobalt-nickel alloy plating layer, rust prevention represented by a single coating treatment of chromium oxide or a mixed coating treatment of chromium oxide and zinc and / or zinc oxide. Processing is performed.

[0009]

Thereafter, as the development of electronic equipment has progressed, the miniaturization and high integration of semiconductor devices have further progressed, and the processing performed in the manufacturing process of these printed circuits has become even higher and products The heat generated during the use of the device after the occurrence of the above has caused a decrease in the bonding strength between the copper foil and the resin base material, which has become a problem. The object of the present invention is to
In a method of treating a copper foil for a printed circuit, a copper plating layer or a cobalt-nickel alloy plating layer is formed after a roughening treatment by copper-cobalt-nickel alloy plating on the surface of the copper foil established in Japanese Patent Publication No. 6-54831. ,
When forming a cobalt-nickel alloy plating layer which is more excellent in heat deterioration resistance than the cobalt plating layer after the roughening treatment, the heat-peelability is further improved.

[0010]

As a result of the study by the present inventors, a surface of a copper foil is roughened by copper-cobalt-nickel alloy plating, and then a cobalt-nickel alloy plating layer is formed. It has been clarified that the formation of a zinc-nickel alloy plating layer can further improve the heat-peeling resistance while keeping the advantages up to now. Based on this finding, the present invention provides a method of treating a copper foil for printed circuits, comprising forming a cobalt-nickel alloy plating layer after roughening treatment by copper-cobalt-nickel alloy plating on the surface of the copper foil, -To provide a method for treating a copper foil for a printed circuit, characterized by forming a nickel alloy plating layer. Preferably, after the formation of the zinc-nickel alloy plating layer, a rust prevention treatment represented by a single coating treatment of chromium oxide or a mixed coating treatment of chromium oxide and zinc and / or zinc oxide is performed. You.

Specifically, in the method for treating a copper foil for a printed circuit, the amount of adhesion on the surface of the copper foil is 15 to 40 mg / dm ^2.
Copper—100 to 3000 μg / dm ² , preferably 200
0-3000 μg / dm ² cobalt-100-500 μ
g / dm ² , preferably 200-400 μg / dm ² After roughening treatment by copper-cobalt-nickel alloy plating such as nickel, the adhesion amount is 200-3000 μg / d.
m ^2, preferably 500~3000μg / dm ² of cobalt -100~700μg / dm ^2, preferably 300 to
A cobalt-nickel alloy plating layer of 700 μg / dm ² nickel is formed, and the adhesion amount is 10 to 200 μg / d.
m ² , preferably 40-180 μg / dm ² zinc-60
２００200 μg / dm ² , preferably 80-200 μg / dm ²
zinc dm ² nickel - forming a nickel alloy plating layer. Preferably, in the roughened copper-cobalt-nickel alloy plating layer and the cobalt-nickel alloy plating layer and the zinc-nickel alloy plating layer thereon, the total amount of deposited cobalt is 300 to 5000 μg / dm ² , preferably 2500. 5,000 μg / dm ² and the total amount of nickel deposited is 260-1000 μg / dm ² , preferably 580-1000 μg / dm ² .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The copper foil used in the present invention is:
Either electrolytic copper foil or rolled copper foil may be used. Usually, the surface of the copper foil that adheres to the resin substrate, that is, the roughened surface, has a bumpy shape on the surface of the degreased copper foil for the purpose of improving the peel strength of the copper foil after lamination. A roughening process for performing the wearing is performed. Although the electrolytic copper foil has irregularities at the time of manufacture, the convexities of the electrolytic copper foil are enhanced by roughening treatment to further increase the irregularities. In the present invention, this roughening treatment is performed by copper-cobalt-nickel alloy plating. Normal copper plating or the like may be performed as a pre-treatment before roughening, and normal copper plating or the like may be performed as a finishing treatment after the roughening to prevent the electrodeposits from falling off. The content of the treatment may be somewhat different between the rolled copper foil and the electrolytic copper foil. In the present invention, known treatments related to copper foil roughening, including such a pretreatment and a finishing treatment, are included as necessary, and are generally referred to as a roughening treatment.

The copper-cobalt-nickel alloy plating as a roughening treatment in the present invention has an adhesion amount of 15 to 40 mg / dm ² copper-100 to 3000 μg by electrolytic plating.
/ Dm ² cobalt—implemented to form a ternary alloy layer such as 100-500 μg / dm ² nickel. If the amount of Co adhesion is less than 100 μg / dm ² , the heat resistance deteriorates and the etching property deteriorates. Co deposition amount is 30
If it exceeds 00 μg / dm ² , it is not preferable when the influence of magnetism must be taken into consideration, and etching stains may occur, and deterioration of acid resistance and chemical resistance may be considered.
If the amount of Ni attached is less than 100 μg / dm ² , the heat resistance becomes poor. On the other hand, when the Ni adhesion amount exceeds 500 μg / dm ² , the etching property is reduced. That is, it is not at a level that an etching residue can be formed or cannot be etched, but it is difficult to form a fine pattern. The preferred Co coverage is 2000-3000 μg / dm ² and the preferred nickel coverage is 200-400 μg / d
m ² . Here, the etching stain means that when etched with copper chloride, Co remains without dissolving, and when the etching residue is alkali-etched with ammonium chloride, Ni remains without dissolving. It means that.

The general bath and plating conditions for forming such a ternary copper-cobalt-nickel alloy plating are as follows: (copper-cobalt-nickel alloy plating) Cu: 10-20 g / liter Co: 1 to 10 g / liter Ni: 1 to 10 g / liter pH: 1 to 4 Temperature: 40 to 50 ° C. Current density D _k : 20 to 30 A / dm ² hours: 1 to 5 seconds

According to the present invention, after the roughening treatment, the adhered amount on the roughened surface is 200 to 3000 μg / dm ² cobalt-100 to 7
A cobalt-nickel alloy plating layer of 00 μg / dm ² nickel is formed. This treatment can be regarded as a kind of rust prevention treatment in a broad sense. This cobalt-nickel alloy plating layer needs to be applied to such an extent that the adhesive strength between the copper foil and the substrate is not substantially reduced. 200μ cobalt deposit
If it is less than g / dm ² , the heat-resistant peel strength decreases, and the oxidation resistance and chemical resistance deteriorate. Another reason is that if the amount of cobalt is small, the treated surface becomes reddish, which is not preferable. 3000μg of cobalt deposit
If / dm ² is exceeded, it is not preferable when the influence of magnetism must be considered, and etching stains occur,
Deterioration of acid resistance and chemical resistance is considered. A preferable cobalt deposition amount is 500 to 3000 μg / dm ² . On the other hand, when the nickel adhesion amount is less than 100 μg / dm ² , the heat-resistant peel strength decreases, and the oxidation resistance and chemical resistance deteriorate. When the nickel adhesion amount exceeds 700 μg / dm ² , the alkali etching property is deteriorated. A preferable nickel deposition amount is 300 to 700 μg / dm ² .

The conditions for cobalt-nickel alloy plating are as follows: (Cobalt-nickel alloy plating) Co: 1 to 20 g / liter Ni: 1 to 20 g / liter pH: 1.5 to 3.5 Temperature: 30 To 80 ° C. Current density D _k : 1.0 to 20.0 A / dm ² hours: 0.5 to 4 seconds

According to the present invention, a zinc-nickel alloy plating layer having a coating amount of 10 to 200 μg / dm ² zinc—60 to 200 μg / dm ² nickel is further formed on the cobalt-nickel alloy plating. Zinc adhesion amount is 10μg / d
If it is less than m ² , there is no effect of improving the heat deterioration rate. On the other hand, when the zinc adhesion amount exceeds 200 μg / dm ² , the rate of deterioration of hydrochloric acid resistance becomes extremely poor. If the amount of nickel adhered is less than 60 μg / dm ² , the rate of deterioration of hydrochloric acid resistance becomes extremely poor, while if the amount of nickel adhered exceeds 200 μg / dm ² , etching residue occurs. Preferably, the zinc coverage is 40-180 μg /
dm ² , particularly preferably 40 to 160 μg / dm ² , and the nickel coverage is preferably 80 to 200 μg / dm ^2.
g / dm ² , particularly preferably 100 to 200 μg
/ Dm ² . The zinc-nickel alloy plating conditions are as follows: (Zinc-nickel alloy plating) Zn: 10 to 30 g / liter Ni: 1 to 10 g / liter pH: 3 to 4 Temperature: 40 to 50 ° C. Current density D _k : 0.5-5A / dm ² hours: 1-3 seconds

According to the present invention, a copper-cobalt-nickel alloy plating layer, a cobalt-nickel alloy plating layer, and a zinc-nickel alloy plating layer are sequentially formed as a roughening treatment. It has been found that the coating weight and the nickel coating weight are important.
For unknown reasons, the three layers behave together. The total cobalt coverage is 300-5000 μg / dm ² and the total nickel coverage is 260-1000 μg / dm ^2.
dm ² is desirable. If the total amount of deposited cobalt is less than 300 μg / dm ² , heat resistance and chemical resistance will be reduced. On the other hand, the total deposited amount of cobalt is 5000 μg /
If it exceeds dm ² , etching stains will occur. If the total amount of nickel deposited is less than 260 μg / dm ² , heat resistance and chemical resistance will decrease. The total amount of nickel deposited is 100
If it exceeds 0 μg / dm ² , an etching residue occurs. Preferably, the total deposit of cobalt is 2500-5000.
μg / dm ² and the total nickel coverage is 5
80 to 1000 μg / dm ² , particularly preferably 600 to
It is 1000 μg / dm ² .

Thereafter, rust prevention treatment is performed as required. In the present invention, a preferable rust preventive treatment is a film treatment of chromium oxide alone or a mixture of chromium oxide and zinc / zinc oxide. The coating treatment of a mixture of chromium oxide and zinc / zinc oxide refers to zinc-containing zinc or zinc oxide and chromium oxide by electroplating using a plating bath containing zinc salt or zinc oxide and chromate.
This treatment covers the rust-preventive layer of the chromium-based mixture. As a plating bath, typically, at least one of dichromates such as K ₂ Cr ₂ O ₇ and Na ₂ Cr ₂ O ₇ and CrO ₃ and a water-soluble zinc salt,
For example ZnO, and at least one ZnSO ₄ · 7H ₂ O, etc., a mixed aqueous solution of alkali hydroxide is used. Typical plating bath compositions and examples of electrolysis conditions are as follows: (Chromium rust preventive treatment) K ₂ Cr ₂ O ₇ (Na ₂ Cr ₂ O ₇ or CrO ₃ ): 2 to 10 g / liter NaOH or KOH: 10 to 50 g / liter ZnO or _{ZnSO 4 · 7H 2 O: 0.05~10g} / l pH: 7 to 13 bath temperature: 20 to 80 ° C. current density D _k: 0.05~5A / dm ² Time: 5 30 seconds Anode: Pt-Ti plate, stainless steel plate, etc. Chromium oxide requires a coating amount of 15 μg / dm ² or more in terms of chromium and zinc requires 30 μg / dm ² or more.

The copper foil thus obtained has excellent heat-resistant peel strength, oxidation resistance and hydrochloric acid resistance,
₍₂₎ A printed circuit having a pitch of 150 μm or less can be etched with an etching solution, and alkali etching is also possible. Examples of the alkaline etching solution include NH ₄ O
H: 6 mol / l; NH ₄ Cl: 5 mol / l; CuCl ₂ :
Liquids such as 2 mol / liter (temperature 50 ° C.) are known.

More importantly, the obtained copper foil is made of Cu
-Has black color as in the case of the Ni treatment. Such black color is important in terms of high alignment accuracy and high heat absorption. Specifically, printed circuit boards, including rigid boards and flexible boards, are equipped with components such as ICs, resistors, and capacitors in an automated process.
At that time, the chip is mounted while reading the circuit with the sensor. At this time, the alignment on the copper foil treated surface may be performed through a film such as Kapton. The same applies to the positioning at the time of forming the through hole. At this time, the closer the processing surface is to black, the better the light absorption, and thus the higher the positioning accuracy. Further, when producing a substrate, the copper foil and the film are often subjected to curing while being heated and adhered. In this case, when heating is performed by using long-wavelength waves such as far-infrared rays and infrared rays, the black surface tone of the treated surface improves the heating efficiency.

Finally, if necessary, a silane treatment for applying a silane coupling agent to at least the roughened surface on the rust-preventing layer is performed mainly for the purpose of improving the adhesive strength between the copper foil and the resin substrate. The application method may be any of spraying of a silane coupling agent solution, application with a coater, immersion, and pouring. For example, Japanese Patent Publication No. 60-15654 describes that the adhesive strength between a copper foil and a resin substrate is improved by performing a silane coupling agent treatment after performing a chromate treatment on a rough surface side of the copper foil. . Please refer to this for details. Thereafter, if necessary, an annealing treatment may be performed for the purpose of improving ductility of the copper foil.

[0023]

EXAMPLES Examples and comparative examples will be described below. The rolled copper foil is subjected to a roughening treatment by copper-cobalt-nickel alloy plating under the following condition range, and copper is added at 17 mg / dm.
^2, cobalt and 2200μg / dm ² and nickel after 300 [mu] g / dm ² deposited, washed with water, cobalt thereon - to form a nickel alloy plating layer. The deposited amount of cobalt was set to 800 to 1400 μg / dm ² and the deposited amount of nickel was set to 400 to 600 μg / dm ² . After washing, a zinc-nickel alloy plating layer, a zinc plating layer, or a nickel plating layer was formed on the cobalt-nickel alloy plating layer. The amount of zinc deposited was 0-250 μg / dm ² and the amount of nickel deposited was 0-300 μg / dm ² . Finally, a rustproofing treatment was carried out and dried. Therefore, the total deposited amount of cobalt in the three layers is 3000 to 3600 μg / dm ^2.
And a total nickel coverage of 700-1000 μg
/ Dm ² . Comparative Example Sample No. shows the case where cobalt plating was performed instead of the cobalt-nickel alloy plating after the above-described roughening treatment. 4 (800 μg / dm ² );
11 (1200 μg / dm ² ). On the cobalt-nickel alloy plating layer after the roughening treatment, zinc-
The comparative sample to which no nickel was attached was designated as No. No. 15 (only cobalt-nickel alloy plating), No. 22 ((cobalt-nickel alloy plating) + nickel plating) and No. 22 16, 19 ((Cobalt-nickel alloy plating)
+ Zinc plating).

The sample was laminated and bonded to a glass cloth substrate epoxy resin plate, and peeled at normal (room temperature) (kg / cm).
Was measured, and the heat resistance deterioration was shown as a deterioration rate (%) of the peel strength after heating at 180 ° C. for 48 hours.
% Immersion in 1% hydrochloric acid for 1 hour
It is shown as a deterioration rate (%) when measured with 10 circuits. In the alkaline etching, the following liquids were used to visually observe the etching state. (Alkali etching solution) NH ₄ OH: 6 mol / l NH ₄ Cl: 5 mol / l CuCl ₂ .2H ₂ O: 2 mol / l Temperature: 50 ° C. Etching stains were made using the following copper chloride-hydrochloric acid solution. The etched state was visually observed. (Copper chloride etching solution) CuCl ₂ .2H ₂ O: 200 g / liter HCl: 150 g / liter Temperature: 40 ° C.

The bath composition and plating conditions used were as follows: [Bath composition and plating conditions] (A) Roughening treatment (Cu-Co-Ni alloy plating) Cu: 15 g / liter Co: 8.5 g / Liter Ni: 8.6 g / liter pH: 2.5 Temperature: 38 ° C. Current density D _k : 20 A / dm ² hours: 2 seconds Copper adhesion amount: 17 mg / dm ² Cobalt adhesion amount: 2200 μg / dm ² Nickel adhesion amount : 300 μg / dm ² (B) Rust prevention treatment (Co-Ni alloy plating) Co: 4 to 7 g / liter Ni: 10 g / liter pH: 2.5 Temperature: 50 ° C. Current density D _k : 8.9 to 13. 3A / dm ² Time: 0.5 seconds cobalt deposition ^{amount: 800~1400μg / dm 2 (No.1~No.3:} 800μg / dm 2, No.5~No.7: 1000μg / dm 2, No.8 ~ No 10, No.15~No.29: 12
No. 00 μg / dm ² , 12-No. 14: 1400μg / dm ²⁾ Nickel coating ^{weight: 400~600μg / dm 2 (No.15~No.22:} 600μg / dm 2, No.23~No.29: 400μg / dm 2) (C) Heat peelability Improvement treatment (Zn-Ni) Zn: 0 to 20 g / liter Ni: 0 to 5 g / liter pH: 3.5 Temperature: 40 ° C. Current density D _k : 0 to 1.7 A / dm ² hours: 1 second Zn adhesion amount ^{: 0~250μg / dm 2 (No.1~14:} 150μg / dm 2) Ni deposition ^{amount: 0~300μg / dm 2 (No.1~14:} 100μg / dm 2) (D) rust (chromate) K ₂ Cr ₂ O ₇ (Na ₂ Cr ₂ O ₇ or CrO
_3): 5 g / l NaOH or KOH: 30 g / liter ZnO or _{ZnSO 4 · 7H 2 O: 5g} / liter pH: 10 Temperature: 40 ° C. Current density D _k: 2A / dm ² Time: 10 seconds anode: Pt-Ti Board

[0026]

[Table 1]

[0027] In Table 1, Co and Ni deposition amount are expressed as the following total amount: (A) roughening treatment (Cu-Co-Ni) Co : 2200μg / dm 2, Ni: 300μg / dm 2 (B ) Rust prevention treatment (Co-Ni) Co: 800 to 1400 μg / dm ² , Ni: 400 to 600 μg / dm ² (C) Heat resistance improvement treatment (Zn-Ni) Zn: 0 to 250 μg / dm ² Ni: 0 to 300 μg / Dm ² etching residue, 22 only, good otherwise. No etching stain was observed in any of the samples.
From Table 1, it can be seen that: (1) When the amount of zinc and nickel deposited in the zinc-nickel alloy plating process is fixed, the amount of cobalt deposited and the amount of nickel deposited in the cobalt-nickel alloy plating process increase, and the heat deterioration rate increases. Decrease. When the cobalt-nickel alloy plating treatment is a cobalt treatment, the heat resistance deterioration rate and / or the hydrochloric acid resistance deterioration rate deteriorate.
(No. 1 to No. 14) (2) When the amount of nickel deposited in the zinc-nickel alloy plating treatment is constant, the amount of zinc deposited is 200 μg / d.
If it exceeds m ² , the rate of deterioration of hydrochloric acid resistance rapidly deteriorates. or,
When the zinc-nickel alloy plating treatment is not performed, and when the zinc-nickel alloy plating treatment is nickel treatment, the heat deterioration rate is deteriorated. (No. 15 to No. 2
2) (3) The amount of nickel deposited in the zinc-nickel alloy plating treatment is less than 60 μg / dm ² , that is, 50 μg / d
If m ² , the rate of deterioration of hydrochloric acid resistance becomes poor. (No. 23-
No. 29) From the above, according to the present invention, it is possible to improve the heat deterioration resistance and to obtain a copper foil for a printed circuit having characteristics in which both the heat deterioration rate and the hydrochloric acid deterioration rate are balanced. I understand.

[0028]

According to the present invention, copper-cobalt-
After the roughening treatment by nickel alloy plating, in a method of treating a copper foil for a printed circuit forming a cobalt-nickel alloy plating layer, it succeeded in further improving the heat-peeling resistance while keeping its beneficial advantages, Provided is a method for processing a copper foil capable of coping with a high temperature of a process accompanying recent rapid development of a semiconductor device and a high density and a high multilayer for a printed circuit.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-231161 (JP, A) JP-A-6-280047 (JP, A) JP-A-2-292894 (JP, A) 169168 (JP, A) JP 6-54831 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) C25D 5/00-7/12 H05K 3/38 H05K 1/09

Claims (7)

(57) [Claims] 1. A method for treating a copper foil for a printed circuit, comprising: forming a cobalt-nickel alloy plating layer on a surface of the copper foil after roughening treatment by copper-cobalt-nickel alloy plating;
A method for treating a copper foil for a printed circuit, further comprising forming a zinc-nickel alloy plating layer. 2. The method for treating a copper foil for a printed circuit according to claim 1, wherein a rust preventive treatment is performed after forming the zinc-nickel alloy plating layer. 3. The copper foil for a printed circuit according to claim 2, wherein the rust preventive treatment is a single film treatment of chromium oxide or a mixed film treatment of chromium oxide and zinc and / or zinc oxide. Processing method. 4. A method for treating a copper foil for a printed circuit, wherein the amount of adhesion on the surface of the copper foil is 15 to 40 mg / dm ² copper-100.
３3000 μg / dm ² cobalt-100-500 μg
/ Dm ² after roughening treatment by nickel-copper-nickel alloy plating, the adhesion amount is 200 to 3000 μg / d
forming a cobalt-nickel alloy plating layer of m ² cobalt-100 to 700 μg / dm ² nickel, and further having an adhesion amount of 10 to 200 μg / dm ² zinc-60 to 200 μg /
zinc dm ² nickel - claims 1-3 any one treatment method of the printed circuit copper foil, which comprises forming a nickel alloy plating layer. 5. The method according to claim 1, wherein the total amount of deposited cobalt is 300 to 500.
0 μg / dm ² and a total nickel coverage of 2
The method for treating a copper foil for a printed circuit according to claim 4, wherein the amount is 60 to 1000 μg / dm ² . 6. A method for treating a copper foil for a printed circuit, wherein the amount of adhesion on the surface of the copper foil is 15 to 40 mg / dm ² copper-200.
0-3000 μg / dm ² cobalt -200-400 μ
g / dm ² nickel after copper-cobalt-nickel alloy plating roughening treatment, the adhesion amount is 500-3000 μg /
dm ² Cobalt-Copper-nickel alloy plating layer of 300-700 μg / dm ² nickel is formed, and the coating amount is 40-180 μg / dm ² Zinc-80-200 μg
/ Dm ² of nickel zinc - processing method of a copper foil for printed circuit according to claim 1 to 3 any one, characterized by forming a nickel alloy plating layer. 7. The total deposited amount of cobalt is 2500 to 50.
00μg / dm is ² and processing method of a printed circuit copper foil according to claim 6 total deposition amount of nickel is 580~1000μg / dm ^2.