Heavy aluminum wire bonding-a state of the art assessment

Ultrasonic wire bonding of Al wire from 0.005" to 0.020" in diameter is being increasingly used for devices where high currents and high heat dissipation are required. Most of this type of bonding is done on an Orthodyne 360 bonder, which offers unique capabilities and constraints. This paper analyzes the bond process and demonstrates how good bonds are made, what their characteristics are, and discusses their impact on design considerations. Sound design rules are explained and demonstrated.