High Performance UV-A Detector Using Axial n-ZnO/p-CuO p-n Junction Heterostructure Nanowire Arrays

UV-A photodetector (PD) based on axial n-ZnO/p-CuO heterostructure (HS) nanowires (NWs) array was fabricated using GLAD (glancing angle deposition) technique. The high resolution transmission electron microscope (HR-TEM) images confirmed the formation of axial HS NWs. The PD shows a high rectification ratio of ~ 278, with low dark current of 0.49 nA (at –1V) and fast photoresponse with rise time and fall time of 0.18 ms and 0.24 ms respectively. A high detectivity of (0.05 TJones) and low noise equivalent power of (70 pW) was also observed at +3 V for the proposed device.