Influence of annealing on reverse current of 4H-SiC Schottky diodes

In this work, we show results of our measurements of the forward and reverse I-V characteristics of Ni/4H-SiC Schottky rectifiers, which were observed prior and after annealing of devices in various gases (Ar, Ar+H-2). We investigate the influence of temperature and atmosphere of annealing on diodes properties. The annealing has no influence on forward I-V characteristics, but the reverse leakage current is reduced as a result of decreasing number of surface states. This phenomenon decreases generation of minority carriers due to reduction of the number of available discrete energy levels in the bandgap of investigated material. (C) 2002 Elsevier Science B.V. All rights reserved.