Distinguishing the EH 1 and S 1 defects in n-type 4H-SiC by Laplace DLTS

We report on the low-energy electron and fast neutron irradiated 4H-SiC studied by deep-level transient spectroscopy (DLTS) and Laplace DLTS. Irradiations introduced two defects, E c −0.4 eV and E c −0.7 eV. They were previously assigned to carbon interstitial (C i ) labeled as EH 1/3 and silicon-vacancy ( V Si ) labeled as S 1/2 , for the low-energy electron and fast neutron irradiation, respectively. This work demonstrates how Laplace DLTS can be used as a useful tool for distinguishing the EH 1 and S 1 defects. We show that EH 1 consists of a single emission line arising from the C i ( h ), while S 1 has two emission lines arising from the V Si ( h ) and V Si ( k ) lattice sites.