TY - JOUR T1 - Device characteristics of CZTSSe thin-film solar cells with 12.6% efficiency JF - Advanced Energy Materials Y1 - 2014 A1 - Wang, Wei A1 - Winkler, Mark T A1 - Oki Gunawan A1 - Tayfun Gokmen A1 - Todorov, Teodor K A1 - Zhu, Yu A1 - Mitzi, David B VL - 4 KW - wang2014device ER - TY - JOUR T1 - Band tailing and efficiency limitation in kesterite solar cells JF - Applied Physics Letters Y1 - 2013 A1 - Tayfun Gokmen A1 - Oki Gunawan A1 - Teodor K. Todorov A1 - David B. Mitzi VL - 103 UR - http://dx.doi.org/10.1063/1.4820250 KW - Gokmen2013 ER - TY - JOUR T1 - The path towards a high-performance solution-processed kesterite solar cell JF - Solar Energy Materials and Solar Cells Y1 - 2011 A1 - David B. Mitzi A1 - Oki Gunawan A1 - Teodor K. Todorov A1 - Kejia Wang A1 - Supratik Guha KW - Solution processing AB - Despite the promise of thin-film Cu(In,Ga)(S,Se)2 (CIGSSe) chalcopyrite and CdTe photovoltaic technologies with respect to reducing cost per watt of solar energy conversion, these approaches rely on elements that are either costly and/or rare in the earth's crust (e.g., In, Ga, Te) or that present toxicity issues (e.g., Cd), thereby potentially limiting these technologies in terms of future cost reduction and production growth. In order to develop a photovoltaic technology that is truly compatible with terawatt deployment, it is desirable to consider material systems that employ less toxic and lower cost elements, while maintaining the advantages of the chalcopyrite and CdTe materials with respect to appropriate direct band gap tunability over the solar spectrum, high device performance (e.g., >10% power conversion efficiency) and compatibility with low-cost manufacturing. In this review, the development of kesterite-based Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells, in which the indium and gallium from \{CIGSSe\} are replaced by the readily available elements zinc and tin, will be reviewed. While vacuum-deposited devices have enabled optimization within the compositional phase space and yielded selenium-free \{CZTS\} device efficiencies of as high as 6.8%, more recently a liquid-based approach has been described that has enabled deposition of \{CZTSSe\} devices with power conversion efficiency of 9.7%, bringing the kesterite-based technology into a range of potential commercial interest. Electrical characterization studies on these high-performance \{CZTSSe\} cells reveal some of the key loss mechanisms (e.g., dominant interface recombination, high series resistance and low minority carrier lifetime) that limit the cell performance. Further elucidation of these mechanisms, as well as building an understanding of long-term device stability, are required to help propel this relatively new technology forward. VL - 95 UR - http://www.sciencedirect.com/science/article/pii/S0927024810006719 KW - Mitzi2011 ER -