Silicon Carbide Static Induction Transistor with Implanted Buried Gate
Buried gate static induction transistors (BGSITs) were fabricated on commercial 4H-SiC wafer with 20 m thick n-type epilayer having a net donor density of 0.71015 cm-3. Buried gate regions were formed by the selective implantation of high energy (up to 2 MeV) aluminium performed at 600 °C. Nitrogen was implanted at temperature of 400 °C to form a heavily doped blanket source region. Post-implantation annealing was carried out at the atmospheric pressure in argon using a graphite capping layer. Fabricated normally-on devices with source contact diameter of 0.2 mm were tested at temperatures up to 500 °C and current densities up to 270 A/cm2. The specific on-resistance of a completely open 4H-SiC BGSIT was 34 mcm2 and showed a thermally activated behaviour at temperatures up to 500 °C.
Amador Pérez-Tomás, Philippe Godignon, Miquel Vellvehí and Pierre Brosselard
K. Vassilevski et al., "Silicon Carbide Static Induction Transistor with Implanted Buried Gate", Materials Science Forum, Vols. 615-617, pp. 735-738, 2009