Preparation and Characterization of II-VI Group Thin Films

Abstract

Cadmium Sulfide (CdS) polycrystalline thin films were grown on corning glass substrate by Close Spaced Sublimation (CSS) technique. Films were immersed in low concentrated (0.1g/100mL) AgNO3–H2O solution (ion-exchange process) at room temperature to get Agdoped films. The structural and morphological investigations were performed by means of X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). Structural study showed that the deposited films exhibit a polycrystalline structure with <111> as preferred orientation. Optical and Electrical measurements were examined by UV-VIS/NIR spectrophotometer (Perkin Elmer Lambda 900 ) and Hall apparatus, respectively. The structural, optical and electrical properties of these films were analyzed as a function of the film thickness and Ag-concentration (mass %). The deposited films showed that the value of resistivity decreased with increasing thickness and Ag-concentration as well, manifesting the semi conducting behavior of the films. The structural study showed that with increase in film thickness grain size increased but optical transmission slightly decreased.