First-principles study on intrinsic defects of SnSe

Abstract

The formation energies and electronic properties of intrinsic defects of SnSe, including two vacancies (V_Sn and V_Se), two interstitials (Sn_i and Se_i) and two antisites (Sn_Se and Se_Sn), are investigated by using density functional theory (DFT) calculations. The results indicate that, due to a relatively low formation energy as well as a desirable ultra-shallow transition energy level, V_Sn can act as an effective source for p-type conduction under both Sn- and Se-rich conditions, which implies that SnSe is a native p-type semiconductor. On the other hand, a native n-type conduction is unlikely to be realized due to the absence of effective intrinsic sources. In addition, all the three types of intrinsic defects are not capable of inducing magnetism.