A new bond failure wire crater in surface mount device : H. Koyama, H. Shiozaki, I. Okumura, S. Mizugashira, H. Higuchi and T. Ajiki. Proc. IEEE/IRPS, 59 (1988)

Abstract

In the Surface Mount Device(SMD) , a new failure wire crater was studied, and defined as peeling off phenomenon of the wire ball from Si substrate or insulator when soldering heat stress is applied. It only occurs when the package absorbs much water before soldering. To analize this phenomena, conditions of water absorption, soldering heat stress, wafer process(metal1ization and insulator materia1s)and assembly process (wire bonding)were investigated. From these results, it is found that the Cratering occurs when the Si nodules of A1-Si metallization give the damage to the insulator at wire bonding. And this Cratering is accelerated by soldering heat stress (Forces of vaporized pressure of absorbed water and thermal expansion of molding compound).