For fabrication of high efficiency Cu(In,Ga)Se2 (CIGS) solar cell, CdS thin film is usually used as buffer layer. However, since Cd is toxic and also hazard material for environment, Cd-free or Cd-reduced buffer is required for realization of CIGS solar cell as an environment-friendly device. We fabricated Cd-reduced hybrid buffer layer of CdS(Cd-treatment)/Zn(O,S), where CdS was made by dipping into CdS CBD solution for 2 min and Zn(O,S) was deposited by co-sputtering of ZnO and ZnS. The hybrid buffer provided improved short circuit current and open circuit voltage and resultantly high power conversion efficiency. The best CIGS solar cell with the hybrid buffer showed 12.69 % cell efficiency compared to the CdS-buffered standard cell with 13.06 %. The improved efficiency for Cd-treated solar cell was found to be consequence of enhanced response to blue wave length photon and surface passivation of absorber surface by the treatment.

中文翻译：

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用于环保CIGS太阳能电池的Cd减少的CdS / Zn（O，S）混合缓冲层

为了制造高效的Cu（In，Ga）Se2（CIGS）太阳能电池，通常将CdS薄膜用作缓冲层。但是，由于Cd有毒且对环境有害，因此将CIGS太阳能电池实现为环境友好型设备需要无Cd或减少Cd的缓冲液。我们制造了CdS（Cd处理）/ Zn（O，S）的减少Cd的混合缓冲层，其中通过将CdS浸入CdS CBD溶液中2分钟而制得CdS，并通过共同溅射沉积Zn（O，S） ZnO和ZnS。该混合缓冲器提供了改善的短路电流和开路电压，并因此提高了功率转换效率。最佳的具有混合缓冲液的CIGS太阳能电池显示出12.69％的电池效率，而CdS缓冲的标准电池具有13.06％的效率。