Barrier layers for electroplated SnPb eutectic solder joints
摘要
The present invention provides a means of fabricating a reliable C4 flip-chip structure for low-temperature joining. The electrochemically fabricated C4 interconnection has a barrier layer between the electroplated tin-rich solder bump and the ball-limiting metallurgy that protects the terminal metal in the ball-limiting metallurgy from attack by the Sn in the solder. The barrier layer is electroplated through the same photoresist mask as the solder and thus does not require a separate patterning step. A thin layer of electroplated nickel serves as a reliable barrier layer between a copper-based ball-limiting metallurgy and a tin-lead (Sn-Pb) eutectic C4 ball.
申请公布号
US5937320(A)
申请公布日期
1999.08.10
申请号
US19980057205
申请日期
1998.04.08
申请人
INTERNATIONAL BUSINESS MACHINES CORPORATION
发明人
ANDRICACOS, PANAYOTIS CONSTANTINOU;DATTA, MADHAV;HORKANS, WILMA JEAN;KANG, SUNG KWON;KWIETNIAK, KEITH THOMAS