STATUS OF SILICON-CARBIDE (SIC) AS A WIDE-BANDGAP SEMICONDUCTOR FOR HIGH-TEMPERATURE APPLICATIONS - A REVIEW

Silicon carbide (SiC), a material long known with potential for high-t emperature, high-power, high-frequency, and radiation hardened applica tions, has emerged as the most mature of the wide-bandgap (2.0 eV less than or similar to E(g) less than or similar to 7.0 eV) semiconductor s since the release of commercial 6H-SiC bulk substrates in 1991 and 4 H-SiC substrates in 1994. Following a brief introduction to SiC materi al properties, the status of SiC in terms of bulk crystal growth, unit device fabrication processes, device performance, circuits and sensor s is discussed. Emphasis is placed upon demonstrated high-temperature applications, such as power transistors and rectifiers, turbine engine combustion monitoring, temperature sensors, analog and digital circui try, flame detectors, and accelerometers. While individual device perf ormances have been impressive (e.g. 4H-SiC MESFETs with f(max) of 42 G Hz and over 2.8 W mm(-1) power density; 4H-SiC static induction transi stors with 225 W power output at 600 MHz, 47% power added efficiency ( PAE), and 200 V forward blocking voltage), material defects in SiC, in particular micropipe defects, remain the primary impediment to wide-s pread application in commercial markets. Micropipe defect densities ha ve been reduced from near the 1000 cm(-2) order of magnitude in 1992 t o 3.5 cm(-2) at the research level in 1995. Copyright (C) 1996 Elsevie r Science Ltd