Metal organic vapor phase epitaxy growth of (Al)GaN heterostructures on SiC/Si(111) templates synthesized by topochemical method of atoms substitution

Abstract

We report a novel approach for metal organic vapor phase epitaxy of (Al)GaN heterostructures on Si substrates. An approximately 90-100 nm thick SiC buffer layer is synthesized using the reaction between Si substrate and CO gas. Highresolution transmission electron microscopy reveals sharp crystalline interfaces with epitaxial relationship between SiC/Si and AlN/SiC layers. Optimization of SiC morphology and AlN seed layer thickness facilitates the growth of GaN layers free of pits (v-defects). It is also found that Si doping eliminates these defects in the case of growth on SiC templates with non-optimized surface morphology. Thus, synthesis of thin SiC buffer layer is suggested as a solution for the interface problems at the initial stage of III-N on Si epitaxy.

Structure and properties of Ta/Al/Ta and Ti/Al/Ti/Au multilayer metal stacks formed as ohmic contacts on n-GaN

“…Growth of GaN epitaxial layers on substrates of other materials (typically, sapphire, SiC and Si) leads to high dislocation densities due to significant lattice mismatches and differences in the coefficients of thermal expansion [7][8][9]. On the one hand, a high defects density limits the advantages of high breakdown field strength in GaN-based power devices.…”