Photoinduced Noise in Amorphous Semiconductor Films

Abstract

ABSTRACTElectrical noise measurements have been performed on amorphous semiconductor films under irradiation with monochromatic light at different wavelengths. The Power Spectrum Densities (PSDs) of highly photoconductive undoped a-Si:H and a-SiC:H (deposited by glow discharge) in the frequency range .1 – 20 kHz are obtained at room temperature. The analysis is performed upon metal/semiconductor/ITO Schottky barriers. The PSDs vs frequency follow l/fn law and show a change of magnitude when the wavelength of the incident light is varied around the value corresponding to the energy gap.