Development of high-efficiency Cu(InGa)Se2 thin-film solar cells fabricated by a nanoparticles based process

本研究工作采用非真空工艺开发了Cu（InGa）Se 2（CIGS）太阳电池的制备工艺，旨在实现CIGS太阳电池的低成本制备。在这个过程中，纳米粒子被化学合成，然后它们被喷涂/烧结以产生CIGS薄膜。结果表明，Cu-In-Ga-Se纳米粒子的晶粒尺寸小，结晶度低，导致电池效率低。以Cu-Se和In-Se纳米粒子为原料，晶化速度加快，晶粒尺寸增大。此外，还提出了一种提高CIS薄膜质量的新方法，即采用硫脲作为粘结剂和烧结助剂，制备高质量的CIS薄膜。与使用Cu-In-Ga-Se纳米颗粒制备的CIGS膜相比，所制备的CIS膜表现出更致密和更大晶粒尺寸的层。最后，成功地制作了转换效率为3.5%的CIS太阳能电池。

In the research work, the fabrication process for Cu(InGa)Se2 (CIGS) solar cells has been developed by using a non-vacuum process, aiming at a realization of low-cost fabrication process for CIGS solar cells. In the process, nanoparticles were chemically synthesized, and then they were spray-printed/sintered to produce CIGS thin films. It was found that the Cu-In-Ga-Se nanoparticles caused small grain size and low crystallinity, resulting in low-efficiency solar cells. The crystallization velocity was increased and the large grain size was obtained when the Cu-Se and In-Se nanoparticles were used as the starting materials. Furthermore, a new approach for the quality improvement of CIS film has been developed, that is, thiourea has been applied as a binding agent and a sintering additive for the fabrication of high-quality CIS film. The fabricated CIS film exhibited a denser and larger-grain-size layer compared with the CIGS film fabricated using Cu-In-Ga-Se nanoparticles. Finally,a CIS solar cell with an efficiency of 3.5% has been successfully fabricated.