Experimental Study on Structural, Optical and Electrical Properties of Chemical Bath Deposited CdZnS Thin Films

[摘要] CdZnS thin films have been prepared from an aqueous solution containing cadmium chloride, zinc acetate and thiourea by chemical bath deposition (CBD) method on a glass substrate at 82°C. Amount of cadmium chloride and zinc acetate were systematically varied as y=0.2, 0.4, 0.6, 0.8 (y=a/(a+b), a=volume of zinc acetate, b=volume of cadmium chloride) and subsequent effects on the film's property were studied by diffractometer, scanning electron microscope, spectrophotometer, four point probe and hall effect measurement. X-ray diffraction result shows that an increase in the Zn-content decreases the crystalline quality of the films. Transmittance and absorbance data was obtained by using UV-Vis spectrometer. Transmittance of 85-90% is found beyond the 700 nm wavelength. Optical bandgaps calculated from these data show a gradual increase in value with a gradual increase in Zn content. The electrical resistance of the so prepared films were measured by four point probe method. The result indicates that the resistance increases with increasing Zn content.

[关键词] Chemical bath deposition;Thin film solar cell;CdZnS;X-ray diffraction;Scanning electron microscope;UV-visiblespectrometry