Thermal resistance of AlGaN/GaN HEMTs on SopSiC composite substrate

In this reported work, the thermal resistance of AlGaN/GaN HEMTs processed on SopSiC composite substrate is determined by electrical I-V pulsed measurement. SopSiC substrate is based on an innovative structure with a thin Si single crystal layer transferred on top of a thick polycrystalline SiC wafer. For the first time, it is demonstrated that the thermal resistivity of such devices reaches 18.9 K mm/W when 7.5 W/mm power is dissipated, while 23.5 K mm/W are measured on silicon in the same conditions. This result shows the capabilities of composite substrates to compete with silicon for microwave power applications.