Enhanced Photodetection in Glancing Angle Deposited One-Dimensional In₂O₃ Nanorod Array.

Abstract

Glancing angle deposition (GLAD) oriented electron beam (e-beam) evaporation process has been employed to develop 1D In₂O₃ nanorod array over n-Si substrate. The morphology of as-deposited In₂O₃ thin film (∼70 nm) and GLAD 1D In₂O₃ nanorod array (∼400 nm) were explored using field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and high resolution transmission electron microscopy (HRTEM) analysis. The structural analysis were perceived by high-resolution X-ray diffraction (HRXRD) and atomic force microscopy (AFM) techniques. The clampdown of ∼4.4 fold photoluminescence (PL) emission intensity was observed for In₂O₃ nanorod array. Metallization were done to measure the current (I)-voltage (V) characteristics for n-Si/In₂O₃ thin film and n-Si/In₂O₃ nanorod devices. The In₂O₃ nanorod device displayed ∼2.2 fold enhancement in current conduction at -4.6 V and an averagely ∼1.1 fold augmentation in photosensitivity were also observed. The photoresponsivity of ∼28 μA/W, maximum specific detectivity of ∼9.9×107 Jones and low NEP of ∼4.5×10-12 W/√Hz was achieved for the In₂O₃ nanorod-based photodetectors. The maximum ∼2.5 fold high detectivity and ∼2.4 fold low noise equivalent power (NEP) were perceived for the 1D In₂O₃ nanorod array detector as compared to the bare In₂O₃ thin film detector.