Amorphous Indium-Gallium-Oxide UV Photodetectors

We report the fabrication of amorphous (InxGa1-x)(2)O-3 metal-semiconductor-metal ultraviolet (UV) photodetectors on glass substrate by co-sputtering. It was found that, we could change the cutoff wavelength of the fabricated photodetectors by changing the RF sputtering power of the In2O3 target. With 5 V applied bias, it was found that the measured dark currents were 2 x 10(-12), 1 x 10(-11), and 2.3 x 10(-11) A for sample A prepared with 40 W In2O3 sputtering power, sample B prepared with 50 W In2O3 sputtering power, and sample C prepared with 60 W In2O3 sputtering power, respectively. It was also found that the UV-to-visible rejection ratios were 3 x 10(3), 5 x 10(3), and 1.5 x 10(4) for samples A, B, and C, respectively. Furthermore, it was found that the response speeds of the fabricated devices were good.