Analysis of stress and strain distribution on pad during bump bonding process

The finite element model of bump bonding is built and loads with conditions of bonding time, bonding pressure and bonding power at the same time, and the stress and strain analysis of the pad will take place using this bump bonding finite element model. The result show that: the stress and strain distribution of the pad is not even and increasing with the time, the largest stress and strain all locate the bonding edge, meanwhile, the small stress and strain all locate the bonding centre and basically remain unchanged in the bonding process, a stress and strain gradient from the bonding centre to the bonding edge appear in the pad. The distribution of stress and strain of pad is reflected from the bump bonding conditions.