Water-Assisted Lift-Off Process for Flexible CdTe Solar Cells
Sandip S. Bista, Deng-Bing Li, Suman Rijal, Sabin Neupane, Rasha A. Awni, Chun‐Sheng Jiang, Chuanxiao Xiao, Kamala Khanal Subedi, Zhaoning Song, Adam B. Phillips, Xixing Wen, Randall J. Ellingson, Michael J. Heben, Yanfa Yan
Abstract
In recent years, various lift-off methods have been developed to fabricate lightweight and flexible cadmium telluride (CdTe)-based solar cells. In this work, we report flexible cadmium sulfide (CdS)/CdTe solar cells using a water-assisted lift-off approach. We demonstrate that an additional cadmium chloride treatment for the CdS film is critical to improve the grain size of CdS and the post-deposited CdTe film and the electron conductivity of the CdS film. As a result, the quality of the CdS/CdTe front junction is significantly improved with reduced nonradiative recombination. Finally, our lightweight and flexible polycrystalline CdTe solar cells demonstrate a champion power conversion efficiency of 12.6%.