Provided is a photodetector in which a transparent nonconductive material having an interface charge and a trapped charge is deposited on a semiconductor surface so as to form a depletion region on the surface of the semiconductor, and the depletion region is employed as an optical detecting region, thereby not only improving detection with respect to light having a wavelength of ultraviolet and blue ranges but also filtering light having a wavelength of visible and infrared ranges, and in which a fabricating process thereof is compatible with a universal silicon CMOS process.