III-V HBTs for microwave applications: technology status and modeling challenges

This paper provides an overview of GaAs HBT applications to microwave power amplifiers, and discusses associated technology challenges, and modeling issues. On-going research efforts with GaInP-GaAs and GaInNAs-GaAs heterostructures are described. The development of comprehensive large signal models for amplifier design is reviewed; nonlinearity mechanisms, saturation effects, thermal effects, ledge effects, and heterojunction effects are discussed.