Zhang Leng, Yu Yongyi, Yu Jing, Wei Yaowei
School of Electronics and Information Engineering, Jinling Institute of Technology, 211169 Nanjing, Jiangsu, People's Republic of China.
State Center for International Cooperation on Designer Low-carbon and Environmental Materials, School of Materials Science and Engineering, Zhengzhou University, 450001 Zhengzhou, People's Republic of China.
R Soc Open Sci. 2020 Oct 7;7(10):200662. doi: 10.1098/rsos.200662. eCollection 2020 Oct.
Quaternary sputtering without additional selenization is a low-cost alternative method for the preparation of Cu(InGa)Se (CIGS) thin film for photovoltaics. However, without selenization, the device efficiency is much lower than that with selenization. To comprehensively examine this problem, we compared the morphologies, depth profiles, compositions, electrical properties and recombination mechanism of the absorbers fabricated with and without additional selenization. The results revealed that the amount of surface Se on CIGS films annealed in a Se-free atmosphere is less than that on CIGS films annealed in a Se-containing atmosphere. Additionally, the lower amount of surface Se reduced the carrier concentration, enhanced the resistivity of the CIGS film and allowed CIGS/CdS interface recombination to be the dominant recombination mechanism of CIGS device. The increase of interface recombination reduced the efficiency of the device annealed in a Se-free atmosphere.
无需额外硒化的四级溅射是一种用于制备光伏用铜铟镓硒（CIGS）薄膜的低成本替代方法。然而，未经硒化处理时，器件效率远低于经过硒化处理的情况。为全面研究这一问题，我们比较了经过和未经额外硒化处理所制备吸收层的形貌、深度分布、成分、电学性质及复合机制。结果表明，在无硒气氛中退火的CIGS薄膜表面的硒含量低于在含硒气氛中退火的CIGS薄膜。此外，表面硒含量较低降低了载流子浓度，提高了CIGS薄膜的电阻率，并使CIGS/CdS界面复合成为CIGS器件的主要复合机制。界面复合的增加降低了在无硒气氛中退火的器件的效率。
