STRUCTURAL, COMPOSITIONAL AND PL PROPERTIES OF Cu(In_(1-x), Ga_x)Se_2 SOLAR CELL ABSORBERS DEPENDENCE ON THE STACKING ORDER OF THE PRECURSOR

摘要

In this study, Cu(In, Ga)Se_2 thin films were prepared by a classical two-stage growth process. This process consists of the formation of Cu-In-(Ga)-Se precursors and subsequent selenization to form CuIn(Ga)Se_2. In this work, the possible interactions in Cu-In-Ga-Se systems were investigated and compared using sequentially stacked precursors, in order to modify the diffusion behavior of gallium and to get a better understanding of the Cu(In, Ga)Se_2 thin film formation. Morphology differences were observed between the different sequences, but the XRD analysis revealed the presence of graded CuIn_(1-x)Ga_xSe_2 structure irrespective of the stacking order during the precursor formation step. The PL spectra of the Cu(In_(1-x), Ga_x)Se_2 films also confirm the process of various deposition orders creates gallium gradient across the films.