Deep-level transient spectroscopic studies of ZnSe-GaAs heterointerfaces

A numerical analysis of the deep-level transient spectroscopy of the ZnSe-GaAs heterojunction based on rigorously solving the Poisson equation and taking account of the interfacial band discontinuity is presented. By combining the numerical analysis with the experimental measurements, properties of the interfacial defects are revealed. It is found that there are donor-like interfacial defects at the ZnSe-GaAs interface with the energy level being located at about 0.5 eV below the conduction band minimum of GaAs, and with an electron capture cross section of 2.5 x 10(-16) cm(2). The areal density of interfacial defects is determined to be 1 x 10(12) cm(2) for ZnSe grown on GaAs substrate treated with S2Cl2.