SiC and GaN Based Transistor and Circuit Advances

Significant progress has been made in the development of SiC MESFETs and MMIC power amplifiers manufactured on 3-inch high purity semiinsulating (HPSI) 4H-SiC substrates. Wide bandwidth circuits using both 10 Watt and 60 watt MESFETs are presented. These MESFETs show no degradation after RFHTOL at a baseplate of 90°C for 4000 hours. High power SiC MMIC amplifiers are shown with excellent yield and repeatability using a released foundry process. GaN HEMTs on HPSI SiC are reported with >30 W/mm RF output power density, and 10 GHz PAE of 72% is also demonstrated for lower voltage devices. Finally, a GaN HEMT operating life of over 500 hours at a TJ =160°C is also reported.