Influence of argon pressure on the crystalline phase formation of RF sputtered zinc sulfide thin films

Abstract

Zinc Sulphide thin films on quartz substrates, were deposited using RF sputtering with variable argon pressures, to assess its effect on the crystallinity and surface morphology. Structural analysis by XRD reveals the formation of crystalline ZnS films, with preferential growth along hexagonal (1 0 3) direction, at a low argon pressure of 0.02 mbar and preferential growth along cubic (1 1 1) direction, at an argon pressure greater than 0.02 mbar. It has been found that crystallinity, is improved at argon pressure of 0.1 mbar. An exponential decrease in film thickness & RMS surface roughness is observed, increasing argon pressure.