Current-voltage characteristics and surface currents in semi-insulating GaAs(Cr)

Abstract

Very recently Kitahara et al. published results of electrical I-V characteristics on GaAs-Cr samples. They found a steep rise in the current which is explained by a space-charge injection phenomenon; some discrepancies still remain unexplained. It will be shown in the present work that Kitahara’s experiments include a surface contribution that seems to be of critical importance.