Photo-detector diode based on thermally oxidized TiO2 nanostructures/p-Si heterojunction

Titanium oxide (TiO2)-based photodetectors were fabricated using a thermal oxidation technique. The effect of two different annealing temperatures on morphology, structure, and I-V characteristics has been investigated. TiO2/Si heterostructure exhibited diode-like rectifying I-V behavior both in dark and under illumination. Dependence in photoresponse on annealing temperature was observed that was related to effective surface area of quasi-one-dimensional TiO2 nanostructures. Fabricated TiO2/Si diodes in 850 degrees C as the lower annealing temperature showed higher responsivity and sensitivity compared with grown ones in 950 degrees C (R-850 degrees C/ R-950 degrees C similar to 5 and S-850 degrees C/ S-950 degrees C similar to 1.6).Rather good photoresponse and simple fabrication process make the 850 degrees C-TiO2/Si diode a promising candidate for practical applications. (c) 2016 AIP Publishing LLC.