CdTe-based solar cells exhibiting 19% power conversion efficiency were produced using widely available thermal evaporation deposition of the absorber layers on SnO 2 -coated glass with or without a transparent MgZnO buffer layer. Evaporating CdSe and CdTe sequentially by thermal evaporation and subsequent CdCl 2 annealing establishes efffective CdSeTe band grading as well as dense, large-grain films. These results show that high-performance II−VI photovoltaics can be made by inexpensive, commercially available evaporation systems without the need to build customized equipment, enabling CdTe photovoltaics research and manufacturing to be more accessible to the broader photovoltaics community.
Buffer layers, such as CdS and Mg x Zn 1−x O (MZO), are critical for CdTe and other thin film polycrystalline solar cells. A ternary compound, such as MZO, allows for interface engineering by adjusting composition, bandgap, and doping to manipulate barriers and recombination to enhance thin film efficiencies toward 25%. Here, theoretical studies demonstrate the enormous impact of front interface offset and emitter doping have on device performance. The results reveal it is possible to achieve 25% device efficiency with open-circuit voltage >1 V, even for 10 5 cm/s recombination velocity, provided the interface offsets and doping are properly engineered.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.