Leadframe for semiconductor
Abstract
Abstract PURPOSE:To improve the reliability by forming an alloy plating layer mainly containing copper and zinc on the surface of a copper leadframe, thereby improving the bondability of an oxidized film, and completing the sealability of semiconductor sealing plastic and the leadframe. CONSTITUTION:An alloy plating layer 2 which mainly contains copper and zinc is formed on the surface of a semiconducator leadframe 1 formed of copper or copper alloy. For example, after the surface of the leadframe 1 formed of copper alloy is pretreated by degreasing and pickling, a plating film 2 of 0.2mum is formed in a copper-zinc plating bath (containing zinc cyanide, copper cyanide, sodium cyanide and Rochelle salt). Further, silver plating 3 is formed in a thickness of 5mum on a tab 5 to be brazed with an Si element and the inner lead 6 wire bonded to all wirings.
Inventors
- 👤 Ryozo Yamagishi
- 👤 山岸 良三
- 👤 Osamu Yoshioka
- 👤 修 吉岡
- 👤 Yoshiaki Wakashima
- 👤 若島 喜昭
Bibliographic Details
Claims Analysis
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