Boosting Self-Powered UV Detection in All-Oxide PIN Heterojunctions via Antireflective Nanostructures and Enhanced
Fuwang Zhou1,2, Kewei Liu1,2, Yongxue Zhu1
1State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, No. 3888 Dongnanhu Road, Changchun130033, PR China.
Abstract:
Self-powered ultraviolet (UV) photodetectors exhibit broad application potential in fields such as space communication, environmental monitoring, and biological analysis. However, while the internal quantum efficiency of current devices has reached a bottleneck, the external quantum efficiency limited by surface/interface reflection losses still offers considerable room for improvement. Constructing nanostructured antireflective surfaces is therefore a critical strategy to overcome this performance bottleneck. Nevertheless, the fabrication of such nanostructured antireflective layers on many wide-band-gap semiconductors is often constrained by complex processes and the introduction of defects. In this work, a mask-free, room-temperature dilute hydrochloric acid (HCl) solution etching technique is successfully employed to fabricate nanostructured antireflective layers on ZnMgO surfaces, and an all-oxide p-NiO/i-ZnMgO/n-ZnO heterojunction self-powered UV photodetector is constructed. This method not only constructs nanostructures that suppress optical reflection but also optimizes the interfacial properties. The optimized device achieves a peak responsivity of 50.5 mA/W at 295 nm under 0 V bias and a high rectification ratio of 5 × 107 at ±5 V and exhibits a fast response speed. This work provides a simple and effective fabrication strategy for developing high-performance self-powered UV photodetectors.
