JPH0841660A - Resin film-coated copper-base material sheet and its production - Google Patents

Abstract

PURPOSE:To produce a resin film-coated copper-base metal sheet excellent in adhesion to the resin. CONSTITUTION:At least a part of the surface of a sheet 1 consisting of copper- base metal is roughened to form a roughened surface 2, and the sheet 1 surface is coated with resin to form a resin coating layer 3. The roughening is conducted by the chemical etching using a mixed soln. of hydrochloric acid and ferric chloride at 40-200A/dm<2> anode current density.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-coated copper-based metal plate in which the surface of a copper-based metal plate is coated with a resin, preferably a heat-resistant and insulating resin such as polyimide, and a method for producing the same.
Particularly, it is suitable for use in narrow pitch connectors for semiconductor devices for high-density mounting that can exert a large shearing force during the manufacturing process, burn-in IC sockets for IC tests that are exposed to thermal cycles under high temperature and high humidity, and the like. TECHNICAL FIELD The present invention relates to a resin-coated copper-based metal plate and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventional resin-coated copper-based metal (copper and copper alloy) plates are made by applying a heat-resistant and insulating resin film to a copper-based metal plate via an adhesive or by directly applying a varnish-like resin. However, in any case, strong bonding was not obtained at the interface between the copper-based metal material and the resin, and there was a problem in adhesion.

[0003]

That is, the resin-coated copper-based metal plate thus prepared can be used without problems in a normal use environment where bending stress and heat load are small, but a large bending stress is applied. When used in a situation,
When used in a situation where it is exposed to a harsh heat load, there is a problem that the coating resin peels off from the surface of the copper-based metal material. For example, in the case of a narrow-pitch connector (connector with a pin interval of about 0.3 mm) used for connecting substrates of a semiconductor device for high-density mounting, it may be shocked during press work or bending work during manufacturing. Shear force acts, which causes peeling at the adhesive interface between the coating resin and the copper-based metal material, or even when peeling does not occur, the adhesive strength at the interface decreases significantly, and it is used during IC testing. When exposed to a harsh heat load during a thermal cycle test under high temperature (maximum temperature 155 ° C) and high humidity (maximum humidity 95%), such as burn-in IC socket Due to the difference in the coefficient of thermal expansion with the resin, a shearing force acts on the adhesive interface between the copper-based metal material and the coating resin, and the adhesiveness of the interface is lost.

Therefore, the present invention has been made to solve the above-mentioned conventional problems, and it has excellent adhesiveness to a resin, and when subjected to press working or bending, high temperature,
An object of the present invention is to provide a resin-coated copper-based metal sheet that has sufficient adhesion and does not peel off even when exposed to a harsh thermal cycle under high humidity, and a method for producing the same.

[0005]

A resin-coated copper-based metal plate according to the invention of claim 1 is made of a copper-based metal having a roughened surface formed by subjecting at least a part of the surface to a roughening treatment. And a resin coating film that covers the surface of the plate material. The resin-coated copper-based metal plate according to the invention of claim 2 is configured such that the roughness of the roughened surface is 1.0 μm or more in center line average roughness (Ra) defined in JISBO601. It In the method for producing a resin-coated copper-based metal plate according to the invention of claim 3, a step of forming a roughened surface by subjecting at least a part of a surface of a plate material made of copper-based metal to a roughening treatment by chemical etching. And a step of coating the surface of the plate material with a resin to form a resin film. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 4, a step of subjecting at least a part of the surface of a plate material made of copper-based metal to a surface roughening treatment by electrolytic etching to form a surface roughened treatment surface. And a step of coating the surface of the plate material with a resin to form a resin film. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 5, the roughness of the roughened surface is 1.0 μm or more in center line average roughness (Ra) defined in JISBO601. Is composed of. The method for producing a resin-coated copper-based metal plate according to the invention of claim 6 is:
In the chemical etching, a mixed solution of hydrochloric acid and ferric chloride is used as an etching solution. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 7, in the electrolytic etching, electrolytic etching is performed under processing conditions of a voltage of 10 V or more and 50 V or less and an anode current density of 40 A / dm ² or more and 200 A / dm ² or less. .

[0006]

In the resin-coated copper-based metal plate according to the first aspect of the present invention, the resin is filled and held in the uneven portions of the roughened surface formed on the surface of the plate material, so that the roughened surface and the resin coating are formed. The adhesive force between them becomes strong, and the adhesion between the plate material and the resin coating improves. In the resin-coated copper-based metal plate according to the invention of claim 2, the roughness of the roughened surface is set to 1.0 μm or more in the center line average roughness (Ra) defined in JISBO601. The adhesive force between the treated surface and the resin coating is further strengthened, and the adhesion between the plate material and the coating resin is further improved. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 3, the adhesive force of the resin film to the plate material is increased by subjecting at least a part of the surface of the plate material to the surface roughening treatment by chemical etching. Adhesion with the resin coating is improved. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 4, the roughening treatment is performed on at least a part of the surface of the plate material by electrolytic etching, whereby the adhesive force of the resin film to the plate material is increased and Adhesion with the resin coating is improved. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 5, the roughness of the roughened surface is set to J
Since the center line average roughness (Ra) defined by ISBO601 is 1.0 μm or more, the adhesive force between the roughened surface and the resin coating becomes stronger, and the adhesion between the plate material and the coating resin is improved. Is further improved. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 6, chemical etching is performed using a mixed solution of hydrochloric acid and ferric chloride as an etching solution. In the method for producing a resin-coated copper-based metal plate according to the invention of claim 7, electrolytic etching is performed under processing conditions of a voltage of 10 V or more and 50 V or less and an anode current density of 40 A / dm ² or more and 200 A / dm ² or less.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view schematically showing an interface between a plate material made of a copper-based metal (copper or copper alloy) of the present invention and a resin coating the plate material, and (a) and (b) are a chemical etching method and an electrolytic method. The center line average roughness of the interface is shown when the etching method is used.

In FIG. 1, reference numeral 1 is a plate material made of a copper alloy as a copper-based metal, and at least a part of the surface of the plate material 1 is roughened to form a roughened surface 2. Has been done. The roughened surface 2 is a portion whose surface roughness is adjusted, and the center line average roughness defined by JISB0601 of this portion is 1.0 μm or more. Further, the surface of the plate material 1 including the roughened surface 2 is covered with a resin such as heat resistant and insulating resin to form a resin coating film 3.

Since the resin-coated copper alloy plate as the resin-coated copper-based metal plate having the above-mentioned structure adjusts the surface roughness of at least a part of the surface thereof, the adhesiveness with the resin film 3 is remarkable. To be strengthened. Therefore, when the resin-coated copper alloy plate of the present invention is used as a substrate for a narrow-pitch connector (connector with a pin interval of about 0.3 mm) used for connecting substrates of a semiconductor device for high-density mounting, Even if a shocking shearing force is exerted during press working or bending during manufacturing, this does not cause peeling at the adhesive interface between the resin coating 3 and the plate material 1. Further, when the resin-coated copper alloy plate of the present invention is used as the substrate of the burn-in IC socket used for the IC test, high temperature (maximum temperature 1
55 ° C., exposed to a harsh heat load during a heat cycle test under high humidity (maximum humidity 95%), due to the difference in thermal expansion coefficient between the plate material 1 and the resin coating 3, the plate material 1 and the resin coating Three
Even if shear force acts on the adhesive interface with
Does not separate from the plate material 1.

Next, a method of manufacturing the resin-coated copper-based metal plate will be described. In the following examples,% represents% by weight.

Embodiment 1. 5. As an example of a manufacturing method for obtaining the resin-coated copper-based metal plate having excellent resin adhesion, nickel (Ni); 9.0%, tin (Sn);
A copper alloy having 0% and the balance being copper (Cu) was manufactured by an age hardening treatment to manufacture a plate material 1 of a copper alloy. This plate material 1
Was used to adjust the surface roughness by a chemical etching method under the following conditions to form a roughened surface 2 having a center line average roughness of 1.0 μm or more.

Treatment condition 1 Composition of etching solution: 10% hydrochloric acid, 20% ferric oxide, temperature: 50 ° C. Then, the roughened surface 2 thus adjusted in roughness is thickened by using an acrylic adhesive. After adhering a 12.5 μm thick polyimide tape, the adhesive was heat-cured to obtain a resin-coated copper alloy plate.

Example 2. As a base material, tin (Sn); 8
%, CDA alloy No. with the balance being copper (Cu) C5
Using the plate material 1 equivalent to 2100, the roughness was adjusted by the electrolytic etching method under the following conditions, and the roughened surface 2 having a center line average roughness of 1.0 μm or more was formed.

Treatment condition 2 Etching solution: Phosphoric acid 100 ml / l Sulfuric acid 10 ml / l Potassium dichromate 15 ml / l Voltage; 30 V Anode current density; 125 A / dm ² Temperature; 40 ° C. And, as in Example 1 above. A resin-coated copper alloy plate to which a polyimide tape was attached was obtained. After cutting the resin-coated copper alloy sheets of Examples 1 and 2 produced in this way into a predetermined shape, the inside radius was made 3 times the sheet thickness and bent to 90 °, and the bent portion was parallel to the bending direction. Was polished. That is, first, using Emily paper (sandpaper), change from coarse to fine one in order (# 80, #
240, # 600, # 800, # 1000), followed by buffing with an alumina abrasive having a particle size of 2.0 μm, and then finishing buffing with an alumina abrasive having a particle size of 0.05 μm. went. When the cross section of the resin-coated copper alloy plate thus produced was observed with a metallographic microscope, no peeling of the interface between the plate material 1 and the resin 3 was observed.

Further, the surface structure of the plate materials 1 of Examples 1 and 2 thus formed was examined by observing with an operating microscope. FIG. 2A is a scanning micrograph (magnification: 1600 times) of the plate material 1 obtained by the chemical etching of Example 1, which has a structure in which voids are formed by particles of several μm to several tens of μm. Can be confirmed. Further, FIG. 3 shows this surface roughness chart and measured values, and it is confirmed from this figure that the center line average roughness is 1.72 μm. FIG. 2B is a scanning micrograph (magnification: 400 times) of the plate material 1 obtained by electrolytic etching of Example 2. From this figure, it is confirmed that the structure has holes having a diameter of several μm to several tens of μm. Can be confirmed. Further, FIG. 4 shows this surface roughness chart and measured values, and it is confirmed from this figure that the center line average roughness is 1.25 μm.

Next, in addition to Embodiments 1 and 2 described above, an embodiment (3,
4, 5), and Examples 6 and 7 in which only the electrolytic etching treatment conditions of Example 2 were changed, and for the purpose of comparison, in order to examine the adhesion of the untreated one to the resin coating, a commercially available epoxy was used. After applying a resin (high moisture resistance type in ThreeBond 2060 series) to the surface of a plate material made of the same material as in Example 1 and not subjected to surface roughening treatment,
The surface roughness (Ra) obtained in the process of obtaining the comparative example 1 and the example 2 prepared by curing was 0.5 μm, 0.
Comparative Examples 2 and 3 having a thickness of 7 μm were prepared, and polyimide varnish was adhered to the symmetrical surfaces on both sides of each resin-coated copper alloy plate thus prepared, and the tensile strength was measured. However, in order to eliminate the change in the shearing force due to the shape, the size of the sample was aligned with a strip having a length of 70 mm and a width of 15 mm, and the test was performed. The results of this tensile test are shown in Table 1. As shown in Table 1, it was confirmed that the examples of the present invention have an adhesion force that resists an extremely large shearing force as compared with the comparative examples.

[0017]

[Table 1]

By the way, the conditions for forming the roughened surface described in each of the above embodiments do not necessarily have to be as described above, but from the viewpoint of etching reactivity of copper alloy, manufacturing cost and the like. It may be appropriately changed within the scope of the present invention. That is, in the case of electrolytic etching, J
In order to obtain a rough surface having a center line average roughness (Ra) defined by ISBO601 of 1.0 μm or more, the voltage is in the range of 10 V to 50 V and the anode current density is 40 A / d.
It is preferable to perform etching in the range of m ² or more and 200 A / dm ² or less. If the base material is copper or a copper alloy generally used as a connector material, the center line average roughness (Ra) of 1.0 μm or more can be obtained by applying the above chemical etching method or electrolytic etching method. It is possible to form a roughened surface.

[0019]

As described above, according to the resin-coated copper-based metal plate of the first aspect, the copper-based metal having the roughened surface formed by subjecting at least a part of the surface to the roughening treatment is used. Since it is provided with a plate material and a resin film that covers the surface of the plate material, the resin is filled and held in the uneven portions of the roughened surface, and the adhesive force between the plate material and the resin film becomes strong, and Even if an impact occurs, the resin coating does not separate from the plate material, and even if a shocking shearing force acts on the interface between the plate material and the resin coating, it exerts sufficient counter force and exerts sufficient resistance between the plate material and the resin coating. There is an effect that the adhesiveness can be secured. According to the resin-coated copper-based metal plate of claim 2, the roughness of the roughened surface is
Centerline average roughness (Ra) defined in JISBO601
Since the thickness is 1.0 μm or more, the adhesive force between the roughened surface and the resin coating is further enhanced, and the adhesion between the resin coating and the plate material is further improved.

According to the method for producing a resin-coated copper-based metal plate of claim 3, at least a part of the surface of the plate material made of copper-based metal is subjected to a roughening treatment by chemical etching to form a roughened surface. Then, since the resin coating is formed by coating the surface of the plate material with a resin, the resin is filled in the concave and convex portions of the roughening-treated surface, and the adhesive force between the plate material and the resin coating is retained, and the adhesive force becomes strong. Even if a thermal shock occurs, the resin coating does not separate from the plate material, and even if a shocking shearing force acts on the interface between the plate material and the resin coating, it exerts sufficient resistance and adheres between the plate material and the resin coating. It is possible to secure the sex.

According to the method for producing a resin-coated copper-based metal plate of claim 4, at least a part of the surface of the plate material made of copper-based metal is subjected to a roughening treatment by electrolytic etching to form a roughened surface. Then, since the resin coating is formed by coating the surface of the plate material with a resin, the resin is filled in the concave and convex portions of the roughening-treated surface, and the adhesive force between the plate material and the resin coating is retained, and the adhesive force becomes strong. Even if a thermal shock occurs, the resin coating does not separate from the plate material, and even if a shocking shearing force acts on the interface between the plate material and the resin coating, the adhesive force between the plate material and the resin coating will be sufficient by exerting sufficient resistance. Can be secured.

According to the method for producing a resin-coated copper-based metal plate of claim 5, the roughness of the roughened surface is determined according to JISBO60.
Since the center line average roughness (Ra) defined by 1 is 1.0 μm or more, the adhesion between the resin coating and the plate material is further improved. According to the method for producing a resin-coated copper-based metal plate of claim 6, in the chemical etching, a mixed solution of hydrochloric acid and ferric chloride is used as an etching solution, so that the etching efficiency in the roughening treatment is high. The desired surface roughness can be obtained in a relatively short time. According to the method for producing a resin-coated copper-based metal plate of claim 7, in the electrolytic etching, electrolytic etching is performed under the processing conditions of a voltage of 10 V or more and 50 V or less and an anode current density of 40 A / dm ² or more and 200 A / dm ² or less. Efficient etching is possible, and the desired surface roughness can be obtained in a relatively short time.

[Brief description of drawings]

FIG. 1A is a sectional view schematically showing an interface between a plate material and a mold resin when a chemical etching method is used, and FIG.
FIG. 4 is a sectional view schematically showing an interface between a plate material and a mold resin when electrolytic etching is used.

FIG. 2A is a scanning micrograph of a roughened surface formed by chemical etching of copper according to the first embodiment (Example 1) of the method for manufacturing a plate material of the present invention, and FIG. It is a scanning micrograph of the roughening process surface formed by the electrolytic etching of copper by the 2nd Example (Example 2) of the manufacturing method of the board | plate material of invention.

FIG. 3 is a graph showing a surface roughness chart and a roughness measurement result of a roughened surface obtained by the first example (Example 1) of the method for manufacturing a plate material according to the present invention.

FIG. 4 is a surface roughness chart of a roughened surface obtained by a second example (Example 2) of the method for manufacturing a plate material of the present invention and a graph showing a result of roughness measurement.

[Explanation of symbols]

 1 plate material, 2 roughened surface, 3 resin coating.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naotake Wada 1-57 Miyashita, Sagamihara City Mitsubishi Electric Metex Co., Ltd. Sagami Factory (72) Inventor Hisatoshi Ito 1-57 Miyashita, Sagamihara Mitsubishi Electric Metex Co., Ltd. Sagami Plant (72) Inventor Mitsuru Haruyama 1-57 Miyashita, Sagamihara City Mitsubishi Electric Metex Co., Ltd. Sagami Plant (72) Inventor Kenji Kubo 1-57 Miyashita, Sagamihara City Mitsubishi Denki Metex Co., Ltd. Sagami Factory

Claims (7)

[Claims] 1. A plate material comprising a copper-based metal having a roughened surface formed by subjecting at least a part of the surface to a roughening treatment, and a resin coating film covering the surface of the plate material. Characteristic resin coated copper metal plate. 2. The roughness of the roughened surface is JISBO
1.0μ in centerline average roughness (Ra) defined by 601
The resin-coated copper-based metal plate according to claim 1, wherein the resin-coated copper-based metal plate is at least m. 3. A plate surface made of copper-based metal is subjected to a surface roughening treatment by chemical etching to form a surface roughened surface, and the surface of the plate material is coated with a resin to form a resin coating. A method for producing a resin-coated copper-based metal sheet, which is characterized by being formed. 4. A plate surface made of copper-based metal is subjected to a surface roughening treatment by electrolytic etching to form a surface roughened surface, and the surface of the plate material is covered with a resin to form a resin film. A method for producing a resin-coated copper-based metal sheet, which is characterized by being formed. 5. The roughness of the roughened surface is JISBO.
1.0μ in centerline average roughness (Ra) defined by 601
It is m or more, The manufacturing method of the resin coat copper system metal plate of Claim 3 or Claim 4 characterized by the above-mentioned. 6. The method for producing a resin-coated copper-based metal plate according to claim 3, wherein a mixed solution of hydrochloric acid and ferric chloride is used as an etching solution in the chemical etching. 7. A voltage of 10 in the electrolytic etching.
V or more and 50 V or less, anode current density 40 A / dm ² or more 2
The method for producing a resin-coated copper-based metal plate according to claim 4, wherein the electrolytic etching is performed under a treatment condition of 00 A / dm ² or less.