Structural and Electrical Transport Properties of CdS and Al-doped CdS Thin Films Deposited by Spray Pyrolysis

Abstract

Cadmium sulfide (CdS) and aluminum (Al) doped cadmium sulfide (Cd1-xAlxS) thin films have been deposited on glass substrate at 300 ºC by spray pyrolysis. The structural and electrical properties of the as-deposited films have been characterized using Energy Dispersive X-ray (EDX) analysis, X-ray diffraction (XRD) and D.C. electrical measurement. The effect of Al on the surface morphology of CdS film was studied by Scanning Electron microscopy (SEM). EDX shows that the deposited samples are stoichiometric. The peak intensities observed in the XRD patterns were found consistent to a polycrystalline hexagonal structure. The XRD study shows that the hexagonal structure of CdS is not much affected with respect to Al doping.  Al-doped CdS thin films show low electrical resistivity of about 48 Ω cm and high carrier density of about 1.1×1019 cm-3.Keywords: Spray pyrolysis; CdS, Cd1-xAlxS; Thin films; EDX; XRD; Hall mobility.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i1.8548J. Sci. Res. 4 (1), 11-19  (2012)