Ultra-high power semiconductor devices: heat-sinking using GaN-on-diamond

GaN devices when operated at high powers are limited by excessive temperature rise in the device critical regions. Traditionally SiC, Si or sapphire substrates or homoepitaxy on GaN substrates are used for the growth of GaN device structures, however, the substrate thermal conductivity is rather limited. Diamond substrates with their ultra-high thermal conductivity offer new opportunities for achieving ultra-high power GaN electronic microwave / RF devices, and optoelectronic devices. This is presently being explored within the UK EPSRC research program GaN-DaME.