HIGH-STRENGTH COPPER ALLOY LEAD FRAME MATERIAL FOR BARE BONDING AND BARE BONDING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a lead frame material for bare bonding which is made of a high-strength copper alloy having a conductivity of not higher than 90%IACS, with an excellent wire bonding property. SOLUTION: The high-strength copper alloy material having a conductivity of not less than 20%IACS and not more than 90%IACS as well as the oxide layer thickness of not more than 100 angstrom. A high-strength copper alloy lead frame material covering the surface of the copper material and consisting of an oxidization preventing film not containing benzotriazol are employed. Bare bonding is effected while maintaining a temperature lower than 250 deg.C whereby an excellent wire bonding property can be obtained.