Reversible Barrier Switching of ZnO/RuO₂ Schottky Diodes

The current-voltage characteristics of ZnO/RuO₂ Schottky diodes prepared by magnetron sputtering are shown to exhibit a reversible hysteresis behavior, which corresponds to a variation of the Schottky barrier height between 0.9 and 1.3 eV upon voltage cycling. The changes in the barrier height are attributed to trapping and de-trapping of electrons in oxygen vacancies.