Conductivity of Sb x Se y films grown by CMBD from Sb and Se precursors for use in solar cells

Abstract

Antimony selenide (Sb 2 Se 3 ) has been developed as attractive, non-toxic and earth-abundant solar absorber candidate among the thin-film photovoltaic devices. The growth of Sb x Se y thin films, by atmospheric pressure chemical molecular beam deposition (CMBD) method, from separate Sb and Se precursors has been reported. The conductivity of the films was investigated as a function of the vapor phase mixture of Sb and Se. By the precise control of the Sb/Se ratio we succeeded in obtaining stoichiometric Sb 2 Se 3 films. It is also found out that we can control the conductivity by deliberately introducing the deviation from the stoichiometry. The conductivity was varied in the wide range of 10 −5 ÷ 10 2 (Ohm × cm) −1 and samples had p- and n-type conductivity depending on Sb/Se ratio. The obtained results were explained by the formation of intrinsic point defects.