Characteristics of CdS: Cu Photosensitive Films Obtatined by Magnetron Sputtering Method

Authors: Emil GUSEINOV, Maarif JAFAROV, Ilham GASANOV, Ilgar NASIBOV

Abstract: In_{2}O_{3}-CdS sandwich structures with thickness 0,5-1,5 \mum have been obtained by magnetron sputtering method on glass substrates. Investigations of dark and light conductivity, the spectrum and kinetics of photoconductivity of CdS films have been carried out. The studies of the current-voltage characteristics of In_{2}O_{3}-CdS have been performed based on the generalized approximate theory of injection contact phenomena in semiconductors. The volume (n_{0}) and precontact (n_{c}) change carrier concentration, recombination (N_{rec}) and trapping (N_{cn}) center concentration, the absorption edge and the transmission coefficient, the region and the maximum of the photocurrent spectral dependence, the life time of nonequilibrium and minority carriers have been determined. With increasing the annealed sample thickness the conductivity has been shown to decrease as L^{-3}, and the voltage at transition from the Ohm's law to a quadratic law increases as L^{2}. It has been found that the In_{2}O_{3} contact is close to a neutral one as a methalic transparent electrode than In. The CdS films obtained by magnetron sputtering method are characterized by high reproducibility, sensitivity, electric strength (10^{6} V/cm), high resistivity (\rho\sim 10^{9}-10^{10} Ohm. cm), optical transmission (more than 60\%). The In_{2}O_{3}-CdS structure is useful as the basic material of an image converter.

Keywords: