Recent developments in compound semiconductor microwave power transistor technology

This paper addresses the state of the art in microwave and millimetre-wave power transistor technology. The relative performance of microwave power transistor technology from 1 GHz to 60 GHz is reviewed. The fundamental technological drivers in the design of microwave compound semiconductor power transistors are discussed as the basis for developing optimum designs. A new high yield power GaAs pHEMT process is described and the application of this technology to multicarrier microwave power amplifiers is discussed, achieving state of the art performance, with output powers of up to 120 W with 70% efficiency at 2.1 GHz.