In this study, gallium nitride (GaN)-based metal-insulator-semiconductor (MIS) ultraviolet (UV) photodetectors (PDs) with a gallium oxide (GaO x) gate layer formed by alternating current bias-assisted photoelectrochemical oxidation of n-GaN are presented. By introducing the GaOx gate layer to the GaN MIS UV PDs, the leakage current is reduced and a much larger UV-to-visible rejection ratio (RUV/vis) of spectral responsivity is achieved. In addition, a bias-dependent spectral response results in marked increase of the RUV/vis with bias voltage up to ∼10 5. The bias-dependent responsivity suggests the possible existence of internal gain in of the GaN MIS PDs.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics