Effect of substrate temperature on thermally evaporated CdS/CZTS for solar cell fabrication

Abstract

The metal chalcogenides has a potential application in energy harvesting systems due to the good optical absorption, much abundance and suitable band potentials. In view of this, n-type Cadmium sulphide (CdS) thin films were thermally evaporated on conducting glass substrate (patterned Indium doped Tin Oxide (ITO) substrates, Ossila S211) followed by the p-type Copper Zinc Tin Sulphide (CZTS) films using nanocrystalline CZTS which in turn was obtained by mechanosynthesis at different milling rates. The mechanosynthesized CZTS nanoparticles and its corresponding films obtained by thermal evaporation were subjected to various characterization techniques such as XRD, UV–Vis-NIR spectroscopy and Hall Effect Measurement techniques in order to understand its physical properties, to access the rate of absorbance and to determine the type of conduction. Moreover, n-CdS as well as p-CZTS films were deposited at different substrate temperatures and studied the effect of temperature on the structural and optoelectronic behaviour of the respective films toward the fabrication of heterojunction solar cells. Finally, the p-n heterojunction was formed using n-CdS/p-CZTS films on patterned ITO substrates.