Dip coated TiO2 based metal-semiconductor-metal ultraviolet photodetector for UV A monitoring

Metal-Semiconductor-Metal ultraviolet photodetector was fabricated by painting silver contacts on dip coated TiO2 thin films. The number of deposition cycles have influence on physiochemical properties and UV sensing properties. The UV photodetector properties were studied by illuminating devices with light intensity of 1.8 mu W/cm(2) and 5 V bias. The fabricated devices show ohmic I-V characteristics. The maximum photocurrent of 0.64 mu A is obtained at 365 nm for film deposited at 8 cycles. The highest photoresponsivity obtained for C-8 sample under UV illumination of 365 nm is 2.15 A/W at 5 V bias. The fast rise and fall times obtained for fabricated device are 17 s and 19 s. The optical switching characteristics show good reproducibility and stability.