Numerical Evaluation of Forward Voltage in SiC Pin Diode with Non-Ohmic Current Component in Contact to p-Type Layer
Forward voltage of SiC pin diodes is evaluated by device simulation, where a p-type contact is described by Schottky barrier to a p-type surface region. The contact resistance is calculated from the comparison to I-V characteristic of Schottky structure to a p-SiC layer with a sufficiently low Schottky barrier height. Even in the relatively low contact resistance rc of 10-4 Wcm2, non-ohmic current component is observed in Schottky structure to p-SiC and the increase of forward voltage of pin diodes is fairly small. Forward voltage of pin diodes increases in the pin diodes with contact resistance rc over 10-4 Wcm2. The same behavior is also observed irrespective of a time constant of carriers, and doping concentration and thickness of a drift layer.
Akira Suzuki, Hajime Okumura, Prof. Tsunenobu Kimoto, Takashi Fuyuki, Kenji Fukuda and Dr. Shin-ichi Nishizawa
K. Ohtsuka et al., "Numerical Evaluation of Forward Voltage in SiC Pin Diode with Non-Ohmic Current Component in Contact to p-Type Layer", Materials Science Forum, Vols. 600-603, pp. 1035-1038, 2009