Title:
LEAD FRAME
Document Type and Number:
Japanese Patent JPH01112757
Kind Code:
A
Abstract:
PURPOSE:To improve the quality of external appearance by providing a tin or tin-lead alloy plated layer on the surface of a lead frame, and defining the thickness of a plated layer on an island part and an inner lead part to be less than a specific thickness, and further providing an Ag plated layer on the upper surface of the plated layer. CONSTITUTION:In a lead frame 1, a tin or tin-lead alloy plated layer 7 is previously provided on the surface of the lead frame. In addition, the thickness of the tin or tin-lead alloy plated layer 7 formed on an inner lead part 4 and an island part 2 is made to be less than 3mum. Further, an Ag plated layer 6 is provided on the tin or tin-lead alloy plated layer 7 in the inner lead part 4 and the island part 2. A soldering property is improved and the rate of production of reddish ground is lowered, thereby improving the corrosion resistance of the lead frame.
Inventors:
YOSHIOKA OSAMU
YAMAGISHI RYOZO
YAMAGISHI RYOZO
Application Number:
JP27052487A
Publication Date:
May 01, 1989
Filing Date:
October 27, 1987
Export Citation:
Assignee:
HITACHI CABLE
International Classes:
H01L23/50; (IPC1-7): H01L23/50
Attorney, Agent or Firm:
Watanabe Noboru Minoru
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