Cd free CIGS solar cells fabricated by dry processes

Dry processes for fabrication of CIGS solar cells are suitable for high throughput mass production based on physical vapor deposition. We report on Cd free CIGS solar cells fabricated by dry processes. To form a homo pn junction, Zn doped into the CIGS surface by Zn evaporation and substrate heating after the preparation of the CIGS films. Zn_1-xMg_xO films with controllable band offset to CIGS films were directly prepared onto the Zn doped surface by sputtering. Cell performances were improved by post-annealing of devices. The cell fabricated by the dry processes showed an efficiency of 16.2%.