Abstract
The Cu2ZnSnS4 (CZTS) thin film with both high carrier concentration of 3.10 × 1020 cm−3 and high mobility of 19.8 cm2/V/s was prepared with optimization of heat treatment technique. In this work, different heat treatment techniques have been applied for the as-deposited CZTS by electrodeposition method. The as-deposited CZTS thin films have suitable Cu-poor and Zn-rich chemical composition, determining the high carrier concentration. The grain boundaries were designed for enhancement of carrier mobility of the CZTS thin films. Multi-step annealing refined the grains and increased the area of the grain boundaries in the films, resulting in the slight decrease of carrier mobility. Based on multi-step annealing, long and narrow particles and the preferential orientation of the grain boundaries formed by the decrease of Ar flow rate in 550 °C annealing. With such structure, the direct transportation of the holes along the vicinity of the grain boundaries increased carrier mobility.
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This work obtained the financial support from National Natural Science Foundation of China (Grant No. 51472020).
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Tang, A., Li, Z., Wang, F. et al. Preparation of Cu2ZnSnS4 thin films with high carrier concentration and high carrier mobility by optimized annealing. J Mater Sci: Mater Electron 29, 7613–7620 (2018). https://doi.org/10.1007/s10854-018-8753-5
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DOI: https://doi.org/10.1007/s10854-018-8753-5