Abstract Little work has been reported on the performance improvement of the β-CIGS solar cell itself even though the β-CIGS phase can have an ideal band gap for high-conversion efficiency solar cells. We incorporated Na2S to β-CIGS film by supplying Na2S to three different stages: on the (In,Ga)2Se3 layer, on the α-CIGS layer, and on the β -CIGS layer in the three-stage co-evaporation process. The purpose of Na2S incorporation was to control the carrier concentration and passivate grain boundaries in β–CIGS film. With Na2S incorporation on the β–CIGS surface, both the Cu and Se concentrations at the β–CIGS surface were greatly reduced and the Na-depleted subsurface area that existed in the referenced β–CIGS film without Na2S was eliminated. The carrier concentration determined at 100 kHz was lowest with Na2S incorporation on the β–CIGS surface, while that determined at 1 MHz was similar with various Na2S supply stages. The open-circuit voltage and fill factor greatly increased in the β–CIGS solar cell with the Na2S incorporation. The cell conversion efficiency with Na2S incorporation on the β-CIGS layer improved from 10.3% to 14.2% without AR coating, which is a record efficiency in β-CIGS solar cells at this time.

中文翻译：

---

通过 β-CIGS 薄膜表面掺入 Na 2 S，将 Cu(In,Ga) 3 Se 5 (β-CIGS) 太阳能电池的转换效率提高 14% 以上

摘要 尽管 β-CIGS 相可以为高转换效率太阳能电池提供理想的带隙，但关于 β-CIGS 太阳能电池本身的性能改进的报道很少。我们通过将 Na2S 供应到三个不同阶段来将 Na2S 加入 β-CIGS 薄膜：在三阶段共蒸发过程中的 (In,Ga)2Se3 层、α-CIGS 层和 β-CIGS 层。Na2S 掺入的目的是控制载流子浓度并钝化 β-CIGS 薄膜中的晶界。随着 β-CIGS 表面的 Na2S 掺入，β-CIGS 表面的 Cu 和 Se 浓度都大大降低，并且在没有 Na2S 的参考 β-CIGS 膜中存在的 Na 耗尽的亚表面区域被消除。在 100 kHz 下测定的载流子浓度最低，在 β-CIGS 表面掺入 Na2S，而在 1 MHz 下确定的结果与各种 Na2S 供应阶段相似。掺入 Na2S 的 β-CIGS 太阳能电池的开路电压和填充因子大大增加。在β-CIGS 层上掺入Na2S 的电池转换效率从没有AR 涂层的10.3% 提高到14.2%，这是目前β-CIGS 太阳能电池的创纪录效率。