Surface passivation and electrical properties of p-CdZnTe crystal

The electrical properties of Au/p-CdZnTe contacts with different surface treatments, especially passivation treatment, are investigated in this paper. After the passivation, a TeO2 oxide layer with a thickness of 3.1 nm on the CdZnTe surface was identified by XPS analysis. Meanwhile, photoluminescence (PL) spectra confirmed that the passivation treatment minimized the surface trap state density and decreased the deep-level defects related to recombination of Cd vacancies. Current-voltage and capacitance-voltage characteristics were measured. It was shown that the passivation treatment could increase the barrier height of the Au/p-CdZnTe contact and decrease the leakage current.