The super-lattice power amplifier with diamond enhanced superjunctions (SPADES) is a device that incorporates nanocrystalline diamond superjunctions into the super-lattice castellated field effect transistor (SLCFET), to improve breakdown voltage. A diamond superjunction is formed with p-type nanocrystalline diamond to balance mutual depletion between the two-dimensional electron gas superlattices and the doped diamond in order to reduce the peak electric field in the drain access region. Formation of the diamond superjunction presents several challenges, such as managing diamond conformality, strain, and control over p-type doping. Optimization of diamond growth led to conformal films, with low stress, and linear dependence hole concentration from p-type doping, suitable for the SPADES device.
Formation of Diamond Superjunctions to Enable GaN-Based Super-Lattice Power Amplifiers with Diamond Enhanced Superjunctions (SPADES)Geoffrey Foster, ASEE Postdoctoral Fellow Residing at NRLTatyana Feygelson, Naval Research LaboratoryJames Gallagher, ASEE Postdoctoral Fellow Residing at NRLJosephine Chang, Northrop GrummanShamima Afroz, Northrop GrummanKen Nagamatsu, Northrop GrummanRobert Howell, Northrop GrummanKarl Hobart, U.S. Naval Research LaboratoryFritz Kub, Naval Research LaboratoryAndrew Koehler, U.S. Naval Research LaboratoryDownload Paper
6a.3 Reduction of Thin Film Stress-induced Micro-masking by Using Ti/Ni Hard Mask for High Power SiC Transistor FabricationShamima Afroz, Northrop GrummanJason Thomen, Northrop Grumman CorporationJames Oliver, Northrop Grumman CorporationEvan Jones, Wolfspeed | A Cree Company