Patent ID: 7025600

Claim:
A method of using a semiconductor device, said device comprising a substrate body; a plurality of external contact terminals formed of springy wires, said external contact terminals arranged on and extending from said substrate body; each of said external contact terminals having a base end connected to said substrate body and a tip end apart from said base end; and each of said external contact terminals being plated on at least said tip end thereof with a film of multiple successively plated layers which are selectively removable by an etching treatment, said method comprising: selectively removing one or more of said layers of said plated film by an etching treatment in accordance with a degree of contamination of the tip end, wherein: an outermost layer of the successively plated layers is dissolvable by a first etching agent but is not reactive to a second etching agent, and a next most outermost layer is dissolvable by the second etching agent but is not reactive to the first etching agent, and said selectively removing comprises using the first etching agent to remove the outmost layer; and rinsing the semiconductor device to enable reuse of same.