the raw materials about the film electrical properties from Effects of annealing atmosphere on the performance of Cu(InGa)Se2 films sputtered from quaternary targets

Quaternary sputtering without additional selenization is a low-cost alternative method for the preparation of Cu(InGa)Se2 (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 to be CIGS/CdS interface recombination. The increase interface recombination reduced the efficiency of the device annealed in a Se-free atmosphere.

无需额外硒化的四元溅射法，是制备光伏用铜铟镓硒（Cu(InGa)Se₂, CIGS）薄膜的低成本替代方案。然而，未经硒化处理的器件光电转换效率远低于经硒化处理的器件。为全面探究这一问题，本研究对比了经额外硒化处理与未经硒化处理制备的吸收层的形貌、深度分布、组分、电学特性以及复合机制。结果表明，在无硒气氛下退火制备的CIGS薄膜的表面硒含量低于含硒气氛下退火制备的CIGS薄膜。此外，较低的表面硒含量会降低载流子浓度、提升CIGS薄膜的电阻率，并使CIGS/硫化镉（CdS）界面复合成为主导复合机制。界面复合的增强会降低无硒气氛下退火制备的器件的光电转换效率。