Synthesis and Characterization of α- Fe2O3 NPs/P-Si Heterojunction for High Sensitive Photodetector

In this work, Fe2O3 nanoparticles (NPs) were synthesized successfully through simple chemical precipitation method. The absorption spectra of the synthesized Fe2O3 NPs was studied by UV-Vis spectroscopy which exhibited absorption peak at 230 nm and band gap of 3.6 eV. The X-ray diffraction analysis (XRD) confirmed the formation of polycrystalline alpha-Fe2O3 with rhombohedral structure. Energy dispersive X-ray analysis (EDX) used to estimate the elemental composition of the Fe2O3 NPs. Spherical shape Fe2O3 NPs with average size of 44 nm was estimated from field emission scanning electron microscopy analysis (FESEM). The dark Current-voltage characteristics (I-V) of alpha-Fe2O3 NPs/p-Si hetrojunction exhibited good rectifying behavior. C-V characteristics reveals the formation of abrupt junction with built in potential of 1.5 V. Under illumination the photocurrent increased as intensity of incident light and reverse bias voltage increased. The fabricated alpha-Fe2O3 NPs/p-Si hetrojunction exhibited promising result as photodetector with responsivity of 0.53 A/W at 550 nm.