Capability study on the destructive pull test of 1 mil gold wire bond and its asymmetric distribution

The Statistical Process Control (SPC) of destructive pull test on 1 Au gold wire is studied on two High-Rel devices, namely #1 and #2. It was found that the Cpk of both parts are around 1.2, which have not meet our goal of 1.33 and the ultimately Six Sigma (Cpk= 2). However, this study shows that the traditional method of calculating Cpk has underestimated the capability of process control if considering the tolerance as asymmetric, such as the case for 1mil gold wire bond.