Paper Title
Improved Fabrication Process for UV/VIS Photodetector and Photo Characteristics Study of Deposited Sb2S3 on TiO2-Graphene Composite Material by Chemical Bath Deposition

Abstract
In this study, TiO2 semiconductor thin film were deposited onto glass substrate by drop coating . Then graphene was grown on copper foil by chemical vapor deposition (CVD) and transferred onto TiO2 semiconductor thin film. Finally, Sb2S3 semiconductor thin film were deposited onto graphene by chemical bath deposition (CBD) respectively. The responsivity of graphene on UV light and visible light was increased with this enhancement. The effect of different casted TiO2 layers on the responsivity of the device was studied. The optimized device was defined. The most suitable responsive wavelength and responsivity of the device were measured by full-spectrum technique. The best responsivity and time response of the optimized device were determined by Xenon (Xe) lamp, Light Emitting Diode (LED) and Laser. Irradiated light with 365 nm and 1 μW by Xe lamp showed best responsivity which is 732 A/W, whereas 365 nm and 50 mW of LED light showed shortest rising and falling time which are 0.16 s and 0.59 s respectively. And Irradiated light with 405 nm and 1 μW by Xe lamp showed best responsivity which is 14.33 A/W, 405 nm and 50 mW of LED light showed shortest rising and falling time which are 4.7 ms and 4.5 ms respectively. The deposition of TiO2 and Sb2S3 semiconductor on graphene photodetector was proven increasing the responsivity of the device and successfully fabricated. Keywords - Graphene, Sol-gel method, Chemical bath deposition, TiO2, Sb2S3, Photodetector, Multiple-unit semiconductor device