Improved Schottky barrier characteristics for AlInN/GaN diodes by oxygen plasma treatment

In this work, the effects of oxygen plasma treatment by inductive coupled plasma on current transport of AlInN/GaN Schottky diodes were investigated. The current-voltage (I-V) results show that oxygen plasma treatment can significantly suppress reverse leakage current of the Schottky diodes by over three orders of magnitude, and meanwhile can enhance remarkably the effective barrier height and improve the ideality factor of the Schottky contact by forming a thin oxidation layer at the AlInN surface. However, I-V curve occurs a transient and recoverable reduction in current response at low forward bias. The further analysis indicates that donor-like traps related to nitrogen vacancies or their complexes induced by oxygen plasma treatment are responsible for this transient current reduction.