Distinguishing the EH1 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 EH1/3 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 EH1 and S-1 defects. We show that EH1 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.