|Title||X-Ray Absorption Spectroscopy Study of Structure and Stability of Disordered (Cu SnS ) (ZnS) Alloys|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Siah, SC, Jaramillo, R, Chakraborty, R, Erslev, PT, Sun, C, Weng, T, Toney, MF, Teeter, G, Buonassisi, T|
|Journal||IEEE Journal of Photovoltaics|
|Pagination||372 - 377|
|Keywords||Amorphous Materials, Annealing, Chalcogenides, CZTS, X-Ray Absorption Spectroscopy|
Secondary phase segregation is hypothesized to have detrimental impacts on Cu2ZnSnS4 (CZTS) thin-film solar cells. In this study, we demonstrate the potential of using kinetic stabilization to inhibit phase decomposition in CZTS. By growing CZTS films at low temperature, we achieve a kinetically stabilized alloy with an expanded solid solution window in the pseudoternary CuS–ZnS–SnS phase diagram. Using X-ray absorption spectroscopy, we study the structural evolution and stability of this metastable alloy upon annealing. For near-stoichiometric samples, we observe a continuous emergence of short-range order toward crystalline CZTS that is nearly complete after a 1-min anneal at 450 °C. For Zn-rich samples, we detect precipitation of ZnS upon annealing, which suggests that the excess Zn exists as cation antisite defects in metastable CZTS.