Phase selective growth of Cu12Sb4S13 and Cu3SbS4 thin films by chalcogenization of simultaneous sputtered metal precursors

Abstract

In this work, it is presented a procedure to grow single phase Cu12Sb4S13 and Cu3SbS4 thin films consisting on the annealing of simultaneously sputtered metal precursors fllowed by a annealing treatment in a sulphur atmosphere. The selection of the ternary phase which is intended to grow is performed by adjusting the sulfur evaporation temperature in chalcogenization process. It is shown that for a sulphur evaporation temperature of 140 ◦C the predominant phase is Cu12Sb4S13 and for 180 ◦C the predominant phase is Cu3SbS4. In order to ensure precursor composition homogeneity, the Cu-Sb metallic precursors are deposited simultaneously by rf magnetron sputtering using adjustable segmented targets. The morphological characterization of the films was made by scanning electron microscopy and the composition was analysed by energy dispersive spectroscopy. The structural analysis and phase identification were performed by X-ray diffraction and Raman scattering. The optical properties were studied through spectrophotometry on films deposited directly on bare glass.