Fabrication and characterization of p-CuS/n-GaN thin film heterojunction diodes

The p-CuS/n-GaN heterojunctions were fabricated successfully using RF magnetron sputtering. It was found that the properties of CuS films with annealing treatment were superior to non-annealed ones through various tests of SEM, XRD, Raman, EDS, and absorption spectrum. The optical band-gap slightly increased after annealing treatment. The current-voltage (I-V) characteristics of p-CuS/n-GaN heterojunction were measured and showed well-defined rectifying behavior for the annealed device.