Growth of Single Crystal Beta Silicon Carbide

Beta-SiC is a promising, wide bandgap material for high power electronic devices capable of operation at high temperatures. Its high saturation velocity, high breakdown electric field, and high thermal conductivity point to superior performance for high frequency applications. The successful fabrication of Beta-SiC devices requires high quality films to be epitaxially grown on lattice-matched substrate materials. Single crystals of Beta-SiC offer the optimum substrate material for lattice matching. The major problem to be overcome in the growth of large single crystals of Beta-SiC is polytype alpha-SiC formation. Cubic Beta-SiC crystallizes only below 2000 deg C. Above this temperature, SiC undergoes a phase transformation from the Beta-to the alpha-phase. In Phase I, we investigated two crystal growth techniques: sublimation and gas-vapor transport. We were able to grow small 3C-SiC crystals by both methods. Original contains color plates: All DTIC and NTIS reproductions will be in black and white.