| 摘要 |
An improvement of joint reliability between Sn-yAg (0<=y<=4.0) solder and Ni-P under-bump metallic layers is achieved by cobalt (Co) addition. A solder joint with improved joint reliability is formed between a solder part of an electronic packaging and an under-bump metallic (UBM) layer, which has a specific structure comprising Sn-yAg-xCo (0.02<=x<=0.1, 0<=y<=4.0) alloy solder containing cobalt (Co) ingredient bonded to a Ni-P UBM. Also, a solder joint with a joint structure comprising Sn-yAg-xCo (0.02<=x<=0.1, 0<=y<=4.0) alloy solder with addition of Co ingredient and Ni-P UBM is formed, which is inserted between a PCB substrate and a silicon chip to join the same. |
