Effect of boron ion implantation on the structural and optical properties of polycrystalline Cd0.96Zn0.04Te thin films

Abstract

Structural and optical studies have been carried out on Cd0.96Zn0.04Te thin films implanted with mass analyzed boron ions (B-10(+)). We have analyzed the properties of the as-deposited and B-10(+) implanted Cd0.96Zn0.04Te thin films using X-ray diffraction, roughness measurement, Raman scattering and optical transmittance measurements. The optical band gap of the as-deposited film is 1.539 eV and the value is found to reduce with the increase in implantation dose. This was accompanied by a progressive reduction in the sharpness of the absorption band edge. Raman spectrum of the as-deposited film shows longitudinal optic and transverse optic modes, which arise from CdTe and ZnTe like vibrations. On implantation the FWHM as well as the relative peak intensity are found to be increased. These results are explained on the basis of the implantation induced surface roughness and lattice disorder. (C) 2002 Elsevier Science B.V. All rights reserved.