Studies on size dependent properties of cadmium telluride thin films deposited by using successive ionic layer adsorption and reaction method

Successive ionic layer adsorption and reaction method (SILAR) have been used to deposit CdTe thin films onto glass substrate using cadmium chloride solution as cationic and sodium tellurite solution as anionic precursor. In order to Study size dependent optical, structural and electrical properties, films having different thicknesses from 96 to 312 nm have been prepared by changing SILAR deposition cycles from 50 to 110. The XRD studies show that films were nanocrystalline in nature with Wurtzite (hexagonal) structure. A shift of band gap energy from 1.86 to 1.47 eV, a decrease in electrical resistivity from 10.52 x 10(1) to 4.78 x 10(1) Omega m (at 528 K), increase ill grain size from 14.5 to 32.8 run and decrease in activation energy from 0.39 to 0.19 eV have been observed when film thickness was varied from 96 to 312 run. The films prepared are semiconducting in nature with p-type conductivity.