Au/n-ZnO rectifying contacts fabricated with hydrogen peroxide pre-treatment

Au contacts were fabricated on pressurized melted grown n-type ZnO single crystal samples pre-treated with boiling organic solvent and hydrogen peroxide. Contacts fabricated without any pre-treatment and with boiling organic solvent pre-treatment were found to have ohmic behavior. For the samples pre-treated with hydrogen peroxide, the Au contacts were found to have rectifying property. Systematic investigation was performed to study the dependence of the Schottky barrier height and the reverse bias leakage current on the temperature and the duration of the pre-treatment. Positron annihilation spectroscopy (PAS), Xray photoemission (XPS) and scanning electron microscope (SEM) were also used to understand how the vacancy type defect, contamination and surface morphology would influence the electrical property of the fabricated contacts.