Realization of High Power MMIC Amplifier in QFN Package at Ka-Band

Achieving high power at high frequency, Ku-band onwards, is a challenge. The interconnect and package effects are considerable at high frequency. Also, the grounding plays a crucial role in suppressing the oscillations in output spectrum. GaAs based high power MMIC (Monolithic Microwave Integrated Circuit) Amplifier die has been selected for packaging. Standard high power QFN (Quad-Flat-No-Lead) package designed to work up to 40 GHz has been used. Various packaging technologies using different solders have been adopted to realize the power amplifier modules. Each module has been characterized and further performance improvement has been carried out by process enhancements. This article details the packaging aspects, void free die-attach techniques as well as interconnection (wire/ribbon) techniques for packaging of high power GaAs MMIC dice in QFN package.