Electrical characteristics modeling of large area boron compensated 6H-SiCpn structures

New models for the high frequency capacitance-voltage, C(V) and forward cur reat-voltage, I-F(V-F) characteristics of a large area 6H-SiC boron compens ated pn junction have been developed and implemented in an optimal paramete r extraction program. The C(V) model and SIMS measurements confirm the presence of two type regio ns (p(-) and n(-)) in the quasi-intrinsic layer induced by boron doping. Th e extracted values of the net doping of these zones (6-10 x 10(12) cm(-3)) are in good agreement with previously reported data. In contrast, the thick ness of the quasi-intrinsic layer, about twice the epilayer width, proves t he expansion of the quasi-intrinsic region in the substrate. The I-F(V-F) modeling includes a square law dependence of the forward curre nt on VF, at high injection level. For the first time in the literature, sa turation currents of SIC pn diodes is reported. The extracted saturation cu rrents increase linearly with area, evidencing the beneficial effect of bor on diffusion for obtaining predictable large area devices. The temperature behavior is also investigated. At high temperatures, the bo ron compensation effect is reduced. (C) 2000 Elsevier Science Ltd. All righ ts reserved.