Fabrication of Cu₂O nanorod using glancing angle deposition technique for photodetector application

In this study, we explore the practical application of Cu₂O nanorod (NR) in photodetection application which is fabricated on Si substrate using e-beam evaporation with an integrated glancing angle deposition (GLAD) technique. Notably, this fabrication method does not rely on catalysts. X-ray diffraction (XRD) analysis reveals two distinct peaks at ~ 36.98° and ~ 43.60°, corresponding to (111) and (200) crystal orientations with an average crystallite size ~ 13.01 nm. This confirms the presence of cuprous oxide (Cu₂O) and thus exhibiting a polycrystalline structure. FE-SEM image examination also confirms the growth of Cu₂O-NRs, displaying a well-aligned structure with average diameter of ~ 30 nm and total length of ~ 250 nm. At a fixed voltage of + 1.5 V, the device remarkably displays a constant switching response when light intensity increases from ~ 0.86 mW/cm² to ~ 2.59 mW/cm². The photodetector records a fall time of rise time of ~ 0.153 s and a fall time of ~ 0.164 s. The device exhibits responsivity in the visible and near-infrared spectrums with its maximum peak intensity observed at ~ 750 nm and a responsivity of ~ 0.9 A/W. Furthermore, the device demonstrates a low noise equivalent power of ~ 8.52 × 10^− 13 W and a detectivity value of ~ 3.29 × 10¹² Jones. The electrical analysis demonstrates a promising photosensitivity characteristic of the Cu₂O-NR device which may be applicable in various optoelectronics applications.