No abstract

Al~traet. CulnSe=o _zlS~x thin films were deposited by spray pyrolysis. Lattice parameters o and c, for all composition parameters X, were calculated from the Phillips X-ray dlffractometer. The structure remained tetragonal chateopyrite throughout, Optical band gap (E~) was determined for the composition parameter X from the transmittance study at room temperature. Variation of E~, a and c with X was found to be linear, Keywords, Ternary semiconductor compounds; spray pyrolysis; chalcopyrite structure.

CuInS 2 is a promising chalcopyrite semiconducting material for solar cell fabrication. Using aqueous solutions of cupric chloride, indium trichloride and thiourea, we deposited thin CuInS 2 films on glass at 350°C and studied their structural, optical and electrical properties. From the XRD pattern the chalcopyrite structure of these films was confirmed. The films were polycrystalline. The grain size estimated from scanning electron mierographs was found to be of the order of 1/~m. Resistivity of the film was measured for temperatures ranging from 77 to 473 K. Band gap values were determined from optical transmission data. Hall mobility and carrier concentration at room temperature were calculated using Van der Pauw-Hall method.

n CulnS2 photoanode has been prepared by spray pyrolysis onto SnO2 deposited glass substrate at 350°C. The conductivity type of the photoanode was tested by hot-probe method and was of n type. The conductivity of the photoanode was of the order of 2-4f2 lcm ~ and was measured by using four-probe method. The effect of etching (HCI:HNO 3 = 5:1 by volume) on photoanode properties has been studied. The best cell had the following parameters: 1~o = 0.29 V, l c = 5.33 mA/cm 2, if= 0.571 and r/= 1.275%.

A CdO thin film was prepared using aqueous solutions of cadmium chloride by spray pyrolysis. The substrate temperature was 350 0 C. Thickness of the films was calculated by using Michelson-interferometer. Electrical resistivity calculated by Four-Probe method for the temperature range 300 0 K to 600 0 K. The two distinct regions corresponding to low and high temperature which indicates the presence of shallows and deep traps level were found.