Thin film solar cells, based on CIGS and perovskites, continue to enhance their market share as promising energy conversion devices for indoor and outdoor applications. Copper Indium Gallium Selenide (CIGS) has been known for its high absorption coefficient, tunable band gap and flexibility. Nevertheless, the use of toxic, regulated elements (Cd) and reliance on rare elements creates a huge barrier in the efforts to enhance the commercial market of CIGS. Perovskite solar cells (PSCs) have attracted increasing scientific and technological interest because of their high efficiency. This is due to their ability to fulfill the multiple roles of light-absorption, charge separation, and transportation of holes and electrons in materials. Furthermore, they contain low amounts of rare earth materials. However, this technology is still limited by the stability, scale-up and the composition of materials. CIGS-Perovskite tandem solar cells continue to demonstrate very high efficiencies in excess of 24%. In this study, an overview of the recent developments in material specifications, deposition techniques and device architecture of CIGS and perovskite solar cells is presented.
