Fabrication and characterization of n-type cadmium telluride nanowires for thin-film solar cell applications

Thin films of n-type cadmium telluride nanowires were produced by electro-deposition into the pores of alumina membranes and were studied for their morphology, chemical composition, crystallite orientation and spectral transmission characteristics. Electrodes were deposited to form ITO/CdTe nanowire/Graphite Schottky diodes and ITO/CdTe nanowire/Indium conducting contact devices and their electrical characteristics were studied. Nanowires of 50 nm diameter and 200 nm lengths, embedded in a matrix of alumina, were obtained. CdTe crystallites in the nanowires were of cubic phase with a <;111>; preferential orientation. Film resistivity in the direction normal to the film was 2.4*10³ Ω-cm. Spectral transmission measurements revealed that for wavelengths below 450 nm, a 200 nm thick CdTe nanowire film had higher transmission than a polycrystalline CdS film of same thickness.