GaN MSM UV Detectors with Different Electrode Materials

Abstract

The different electrode (In-In, Ni-Ni, Ni-In) MSM ultraviolet photodetectors were fabricated on GaN thin film which is grown on sapphire. The test result of the three electrode detectors show that the dark current of In-In device and Ni-Ni device are in the order of 10 -8A and 10 -9A , respectively, at bias of 5-10V. Asymmetric electrode (Ni-In) device has asymmetry dark current and a larger photocurrent than the symmetrical electrode devices. At the same time, Ni-In devices have a self-powered effect, under 0V bias, the photocurrent reaches 8× 10 -9A , and the photoresponse is 5.4mA/W at 360nm.