ELECTRICAL-PROPERTIES OF EPITAXIAL 3C-SIC AND 6H-SIC P-N-JUNCTION DIODES PRODUCED SIDE-BY-SIDE ON 6H-SIC SUBSTRATES

3C-SiC (beta-SiC) and 6H-SiC p-n junction diodes have been fabricated in regions of both 3C-SiC and 6H-SiC epitaxial layers which were grown side-by-side on low-tilt-angle 6H-SiC substrates via a chemical vapor deposition (CVD) process. Several runs of diodes exhibiting state-of- the-art electrical characteristics were produced, and performance char acteristics were measured and compared as a function of doping, temper ature, and polytype. The first 3C-SiC diodes which rectify to reverse voltages in excess of 300 V were characterized, representing a six-fol d blocking voltage improvement over experimental 3C-SiC diodes produce d by previous techniques. When placed under sufficient forward bias, t he 3C-SiC diodes emit significantly bright green-yellow light while th e 6H-SiC diodes emit in the blue-violet. The 6H-SiC p-n junction diode s represent the first reported high-quality 6H-SiC devices to be grown by CVD on very low-tilt-angle (< 0.5-degrees off the (0001) silicon f ace) 6H substrates. The reverse leakage current of a 200 mum diameter circular device at 1100 V reverse bias was less than 20 nA at room tem perature, and excellent rectification characteristics were demonstrate d at the peak characterization temperature of 400-degrees-C.