Novel Piezoelectric Force Sensor Array for Investigation of Ultrasonic Wire Bonding

In this paper, the process chain of a novel 4×3 force sensor array prototype for in-situ detection of the stress distribution during ultrasonic (US) wire bonding process is demonstrated. The sensor is based on d 15 lead zirconate titanate (PZT) 255 ceramic, which is cut into individual columns by precision dicing. Polyimide is then filled among the columns to constitute a new PZT/polyimide hybrid sensor platform. Each PZT column is responsible for the measurement of the local tangential force at the wire/substrate interface during US wire bonding.