Abstract: The present invention provides a tin-based two-layered plating film exhibiting suppressed whisker growth comprising a lower layer of a tin plating film or tin alloy plating film comprising 5% by weight or less of at least one metal selected from the group consisting of cobalt, copper, bismuth, silver, and indium, and 95% by weight or more of tin, and an upper layer of a tin plating film or tin alloy plating film comprising 5% by weight or less of at least one metal selected from the group consisting of cobalt, copper, bismuth, silver and indium, and 95% by weight or more of tin. The tin-based plating film of the present invention is a lead-free tin plating film or tin alloy plating film, exhibits suppressed whisker growth over an extended period, and can further be formed relatively easily without complicated steps.
Type:
Application
Filed:
May 27, 2005
Publication date:
February 28, 2008
Applicants:
RAMBO CHEMICALS (H.K.) LTD., OKUNO CHEMICAL INDUSTRIES CO., LTD.
Inventors:
Chun Wah Jimmy Kwok, Yim Wah Rosaline Kwok, Yutaka Nakagishi