Ga Doped ZnO Nanorods Ultraviolet Photodetectors on Flexible Substrate

Abstract

In this study, high-density single crystalline Ga doped ZnO (GZO) nanorods were grown on flexible substrate by the hydrothermal method. From the FESEM image, it was found that GZO nanorods have a hexagonal wurtzite structure and the average length and diameter of the GZO nanorods were 1.35 μm and 31 nm, respectively. It was also found that high density vertically oriented nanorods are grown on the seed layer/flexible substrate. Further, Ga-doped ZnO nanorods metal-semiconductor-metal (MSM) ultraviolet (UV) photodetectors (PD) were fabricated. Under 1 V applied bias, the dark current and photocurrent of GZO MSM PDs were 8.60 × 10 -9 A and 3.92 × 10 -6 A, respectively. The responsivity of the synthesized GZO PDs were around 0.031 A/W with a sharp cutoff wavelength at 370 nm. The UV-to-visible rejection ratio of the GZO PDs sample was 23.87 as the measured responsivity at UV and visible peaks were 370 and 450 nm, respectively.