Structural analysis of Cu(In,Ga)Se2 thin-films by depth-resolved XAFS
Abstract
Cu(In,Ga)Se2 (CIGS) is a promising material for thin-film photovoltaic devices. Elucidation of the crystal structure of CIGS thin-films is significant for understanding the properties of CIGS solar cells. This study demonstrates the structural evaluation of CIGS thin-films prepared by a three-stage process using Se K-edge depth-resolved X-ray absorption fine structure (XAFS). The CIGS films changed from a Cu-poor to Cu-rich composition during the second stage of the three-stage process. Notably, Cu2-x Se is generated at the surface of the film at the end of the second stage. After the third stage process, CIGS films have a Cu-poor composition from the surface to a depth of 200 nm. Depth-resolved XAFS technique is sufficiently applicable for evaluation of electronic and crystal structure of CIGS thin-film. This study will provide useful information for the elucidation of the structure of CIGS thin films.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- October 2019
- DOI:
- 10.7567/1347-4065/ab4573
- Bibcode:
- 2019JaJAP..58j5502B