Fabrication of homogeneous CIGS thin film by plasma-enhanced Se vapor selenization coupled with etching process

In this study, a novel plasma-enhanced Se vapor selenization coupled with etching (PESVSE) technique is demonstrated to achieve a uniform depth distribution of Ga in the Cu(In, Ga)Se-2 (CIGS) film. The significant increase of Ga concentration on the surface of the CIGS film was ascribed to the removal of the excessive metallic-indium by the Ar-plasma during the PESVSE process and a single phase CIGS film was obtained without phase separation. No small grains or cracks were observed in the CIGS film based on the PESVSE process. The CIGS device obtained from the PESVSE process showed an enhanced conversion efficiency of 8.79%, compared to that of the device obtained from the TASVS process (6.18%). (C) 2017 Elsevier B.V. All rights reserved.