Characteristics of Pt Schottky contacts on hydrogen peroxide-treated n-type ZnO(0001) layers

The effect of hydrogen peroxide (H2O2) treatment on the characteristics of Pt Schottky contacts to n-type ZnO(0001) layers (8×1016–2×1017 cm−3) has been investigated. Pt contacts on conventional organic solvent-cleaned ZnO show fairly leaky behaviour with a leakage current of −0.05 A under −5 V, while Pt contacts on H2O2-treated ZnO give good Schottky behaviour with a leakage current of −6.5×10−8 A under −5 V. Schottky barrier heights extracted from the current–voltage characteristics are in the range 0.88–0.97 eV depending on the ideality factors. Room temperature photoluminescence results show that the hydrogen peroxide treatment is fairly effective in removing deep-level defects near the ZnO surface region.