A study of photostructural changes in amorphous P-Se thin films using IR and X-ray photoelectron spectroscopy

Abstract

The structure of the thin films of P_xSe_1-x deposited at various angles incidence and the photostructural changes occuring therein on illumination with UV light been studied by infrared (IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). IR spectra reveal the absorption bands due P=Se, P-Se-P, and -Se-Se group variations. The coexistence of various types of structural units (SePSe3/2 , PSw3/2 and -Se-Se-) in these films supported by XPS and IR results. The photostructural changes are a consequence of the changes in the relative concentration of these structural units. It has been shown that the magnitude of the photostructural changes is maximum for the composition (P₄Se₁₀) having maximum concentration of fourfold coordinated (SePSe3/2) units.