STUDY OF PHOTO-ELECTRICAL PROPERTIES OF Se90Ag10 AMORPHOUS THIN FILMS
N. K. SINGH
Department of Physics, U. I. E. T, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208024, India.
ANJANI KUMAR
Department of Physics, Harcourt Butler Technological Institute, Kanpur, 208002, India.
D. KUMAR
Department of Physics, J. S. S. Academy of Technical Education, Noida, 201301, India.
S. SHUKLA *
Department of Physics, U. I. E. T, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208024, India.
*Author to whom correspondence should be addressed.
Abstract
Amorphous Se90Ag10 thin films are prepared by vacuum evaporation technique. The present paper reports the temperature and intensity dependence of steady state photoconductivity measurements in the aforesaid thin films. Temperature dependence of conductivity in dark as well as in presence of light shows that conduction is through a thermally activated process in both the cases. The activation energy is found to decrease with the increase in light intensity. This indicates the shift of Fermi level with intensity. The value of photosensitivity is also calculated. The results of intensity dependence of photoconductivity show that it follows a power law σph ∝ Fγ. It is also found that a continuous distribution of localized states exists in the mobility gap of the given glassy system.
Keywords: Thin films, photoconductivity, activation energy, mobility gap