Investigation on interface barrier of Au–CdZnTe contacts

The interface barrier between Au contact and p-CdZnTe was studied by synchrotron-based X-ray photoemission spectroscopy (SXPS), where the interface barrier was determined by the discrepancy between EV−C deduced by the Cd 4d core level with valence band region and EB deduced by the Cd 4d core level with the Fermi edge. The interface barrier height was determined to be 0.88±0.02 eV for Au–CdZnTe without passivation and 1.17±0.02 eV for Au–CdZnTe after passivation. Schottky barrier height was 0.85±0.02 eV without passivation and 0.96±0.02 eV with passivation by current–voltage method. However, 1.39±0.02 eV without passivation and 1.51±0.02 eV with passivation were measured according to the capacitance–voltage method.