Improved photodetector performance of SnO ₂ nanowire by optimized air annealing

Abstract

Abstract This study demonstrates the fabrication of uniform and vertically oriented SnO 2 nanowires (NWs) using glancing angle deposition technique. The SnO 2 NW was then subjected to different annealing temperatures of 350 °C, 550 °C, 650 °C, 750 °C and 900 °C in air, each for 1 h to discover the best optimized photodetector performance. The 650 °C sample showed the best photodetector material properties, with highest optical absorption, crystallinity, and reduced dislocation density. As such, the photodetector based on annealed 650 °C device exhibited an obvious best performance in terms of high responsivity as compared to other annealed samples. Also, a large UV responsivity of 2.58 A W −1 at 300 nm with high detectivity of 64.13 × 10 10 Jones and a low noise equivalent power of 6.56 pW was observed for 650 °C sample. Thus, the increase in the crystallinity along with less scattering of photogenerated carriers enhanced the photoconductivity of 650 °C annealed UV photodetector.