GOLD-TIN SOLDER JOINTS HAVING REDUCED EMBRITTLEMENT

摘要

A metal interconnection for two workpieces such as a semiconductor chip and an insulating substrate. The first workpiece (101) has a first contact pad (201) with a gold stud (110); the second workpiece (103) is covered with an insulating layer (213) and a window in the layer to a second contact pad (211). The interconnection between the second pad and the gold stud is a 278°C eutectic structure (111) with about 80 weight percent gold and about 20 weight percent tin. The eutectic structure has a Young's modulus of 59.2 GPa and a lamellar micro-structure of the phases AusSn and AuSn. There is substantially no metallic tin at the second contact pad.