JPS6114234B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing metal-plated Cu and Cu alloy plates and strips that do not cause any blistering on the metal-plated surface. Conventionally, metal-plated Cu and Cu alloy plates and strips (hereinafter collectively referred to as metal-plated Cu)
(abbreviated as Cu alloy plate material and explanation of the plate material)
First, a Cu or Cu alloy ingot of a specified size is hot-rolled to form a plate material of a specified thickness, which is then face-milled and then annealed, pickled, and rolled in one step.
A plate material of a predetermined thickness is formed by cold rolling, which is performed one or more times depending on the hardness required for the final plate material, and then, successively, continuously or in a predetermined manner. After a period of time has elapsed, the oil adhering to the surface of the plate material is degreased during the final finish rolling in the cold rolling process, followed by etching treatment, and finally metal plating. For example, in the metal-plated Cu alloy plate material manufactured by the method,
When using this material as a lead material for semiconductor devices, there were problems such as frequent blistering on the metal plating surface when heated during the semiconductor assembly process, which significantly deteriorated the yield of semiconductor products. Therefore, from the above-mentioned viewpoint, the present inventors conducted research to obtain a metal-plated Cu alloy plate material that does not cause blisters on the metal-plated surface. When pickling is performed to remove the metal oxide film, a chemical compound (hereinafter referred to as pickling If rolling is performed with the pickling compound present on the surface of the material, the oil-containing pickling compound will firmly adhere to the surface of the material after rolling. Pickling compounds containing oil cannot be completely removed by the usual degreasing and etching processes that are performed as a pre-process to metal plating, and as a result, these pickling compounds remain attached to the surface of the material. Since metal plating will be applied in this state, blisters will occur on the metal plating surface due to the pickling compound. On the other hand, it may be possible to perform a strong etching treatment to completely remove the oil-containing pickling compound, but if such a strong etching treatment is applied, the surface of the board will become extremely rough, and it will not be smooth. A metal-plated surface cannot be obtained. (b) However, instead of pickling treatment using a weakly oxidizing acidic solution (e.g. diluted sulfuric acid) to remove the metal oxide film formed on the surface of the material during annealing, an extremely strongly oxidizing acidic solution, e.g. Brightening treatment liquid (Kirinsu liquid), nitric acid liquid, chromic acid -
If it is completely removed by a polishing process using a sulfuric acid solution or a hydrogen peroxide brightness/scale removal solution (hereinafter referred to as chemical polishing process), the compounds formed on the surface of the material by this chemical polishing process (hereinafter referred to as chemical polishing process) These compounds (compounds) can be easily and completely removed by a normal etching process that is performed after rolling and prior to normal metal plating. There will be no occurrence of blisters. (c) Paragraphs (a) and (b) above apply not only to plates but also to shapes, bars, or wires with circular, square, rectangular, or irregular cross-sectional shapes (collectively referred to as strips). The same applies to The findings shown in sections (a) to (c) above were obtained. The present invention has been made based on the above knowledge, and it is possible to produce Cu and Cu alloy plate material or Cu and Cu alloy strip material (hereinafter collectively referred to as Cu alloy plate material) by normal hot rolling and cold rolling. metal plating, which consists of molding a molded material (known as ``metal plating''), then subjecting it to normal pretreatment, and then applying metal plating.
In the manufacturing method of Cu alloy plate material, at least the final step in the cold rolling process is annealing, chemical polishing,
By making the process consist of final finish rolling,
The feature is that there is no blistering on the metal-plated surface of the metal-plated Cu alloy plate material. In addition, when carrying out the method of this invention,
It is best to make the surface of the Cu alloy plate as smooth as possible after final finish rolling, and the best metal plating surface can be obtained by controlling the average roughness to 0.1 μm or less and the maximum roughness to 1.0 μm or less. be. Next, the method of the present invention will be specifically explained using examples. Example Molten metals of the materials shown in Table 1 were prepared by the usual melting and casting method, and the thickness: 160 mm x width:
After making an ingot with dimensions of 370 mm x length: 1400 mm, the ingot was hot rolled to form a plate-like material with a thickness of 11 mm, and the top and bottom surfaces of this plate-like material were further coated to remove scale. The thickness of the plate is 10mm by face cutting.
Subsequently, the plate material was repeatedly subjected to normal cold rolling, that is, rolling, annealing, and pickling, so that the thickness of the pre-rolled plate was as shown in Table 1. Cu alloy sheets 1 to 4 of the present invention were manufactured by performing annealing under the conditions shown in (1), chemical polishing treatment for removing the metal oxide film generated during the annealing, and finish rolling.

【table】

[Table] On the other hand, for the purpose of comparison, the manufacturing conditions are the same as each of the above-mentioned Cu alloy sheets 1 to 4 of the present invention, except that pickling is performed under the conditions shown in Table 1 instead of the above-mentioned chemical polishing treatment. Comparison Cu alloy plate material 1 under the conditions of
-4 were produced, respectively. Next, for the resulting Cu alloy plates 1 to 4 of the present invention and comparative Cu alloy plates 1 to 4,
Degreasing and etching are performed as a pre-process for metal plating, followed by Ni and Ag metal plating with a thickness of 2 μm under normal electroplating conditions. A metal-plated Cu alloy plate material was heated under the same conditions shown in Table 2, and the occurrence of blisters on the metal-plated surface after heating was observed. As a result, the metal-plated Cu alloy plate material 1 of the present invention
No blistering was observed in any of the comparative metal-plated Cu alloy sheets 1 to 4.
4, a large number of blisters occurred in all cases. As described above, the present invention has industrially useful effects such as being able to manufacture metal Cu and Cu alloy plates and conditions that do not cause blisters on the metal plating surface with extremely simple operations and at low cost. is brought about.

Claims (1)

[Claims] 1 Hot-rolling and cold-rolling an ingot of Cu or Cu alloy to form a plate or strip, then degreasing and etching the plate or strip, and finally applying metal plating. Metal plating Cu and Cu
In the method for manufacturing alloy plates and strips, after annealing in at least the final step of the cold rolling step, a chemical polishing treatment is performed to completely remove the metal oxide film formed on the material surface by the annealing. 1. A method for producing metal-plated Cu and Cu alloy plates and strips, which comprises the steps of: rolling, followed by final finish rolling.