Improving RF Power Amplifier Performance Through Bond Wire Loop Height Optimization

This paper presents a technique wherein a critical component of a system-in-package (SiP) power amplifier (PA) module, the bond wire loop height, was tuned and optimized to improve its output power performance. Varying the bond wire loop height does not entail major product modification, no additional material or process to be performed. It is process-centered, thus process control should be always guaranteed by process capability (CpK) of the production unit. The use of a simulation tool greatly reduced the design cycle time for the experiment. The effects of the loop height variation were observed and became the basis in performing the experiment. Actual PA modules with varied loop heights were tested and measured of their output power. With the positive results of the experiment, it was then expanded to a confirmation run, with greater module quantity. The corresponding improvement in product performance and yield are also discussed.