UV–visible light detection with TiO2 thin film deposited on chemically textured p-Si substrate

Abstract

This paper reports a study on the photodetection properties of TiO2 thin film deposited on chemically textured p-Si substrate and is compared to those deposited on pristine p-Si substrate. The structural properties of both the heterostructures were investigated using XRD analysis. FESEM images confirmed the deposition of TiO2 thin film on chemically pyramidal textured Si substrate. The average total reflectance of the textured Si substrate was reached to ~ 7.6% in the wavelength range of 300–900 nm. It was further decreased to ~ 6.5% after the deposition of 55 nm thick TiO2 on the top of the textured Si substrate. A systematic study was carried out to correlate the structural, optical and electrical properties of both the heterostructures. The electrical parameters of the heterojunction diodes were measured and compared under dark and illuminated conditions using UV and solar simulated light. UV as well as visible light detection property of the heterostructure of TiO2 thin film deposited on pyramidal textured Si substrate was improved compared to the one deposited on pristine Si by the factor 2.0 and 1.86, respectively, under the bias of − 2 V.