Reactive Mechanism of Cu2ZnSnSe4 Thin Films Prepared by Reactive Annealing of the Cu/Zn Metal Layer in a SnSex + Se Atmosphere
Liyong Yao,
Jianping Ao,
Ming-Jer Jeng,
Jinlian Bi,
Shoushuai Gao,
Guozhong Sun,
Qing He,
Zhiqiang Zhou,
Yi Zhang,
Yun Sun,
Liann-Be Chang
Affiliations
Liyong Yao
Tianjin Institute of Power Source, Tianjin 300384, China
Jianping Ao
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Ming-Jer Jeng
Department of Electronic Engineering, Chang Gung University, KueiShan 333, Taiwan
Jinlian Bi
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Shoushuai Gao
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Guozhong Sun
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Qing He
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Zhiqiang Zhou
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Yi Zhang
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Yun Sun
Institute of Photoelectronic Thin Film Devices and Technology of Nankai University, Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Key Laboratory of Optical Information Science and Technology of Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
Liann-Be Chang
Department of Electronic Engineering, Chang Gung University, KueiShan 333, Taiwan
Cu2ZnSnSe4 (CZTSe) thin films were prepared by a two-step process with the electrodeposition of a Cu/Zn metallic stack precursor followed by a reactive anneal under a Se + Sn containing atmosphere. We investigate the effect of the Sex and SnSex (x = 1,2) partial pressures and annealing temperature on the morphological, structural, and elemental distribution of the CZTSe thin films. Line scanning energy dispersive spectroscopy (EDS) measurements show the presence of a Zn-rich secondary phase at the back-absorber region of the CZTSe thin films processed with higher SnSex partial pressure and lower annealing temperatures. The Zn-rich phase can be reduced by lowering the SnSex partial pressure and by increasing the annealing temperature. A very thin MoSe2 film between the CZTSe and Mo interface is confirmed by X-ray diffraction (XRD) and grazing incidence X-ray diffraction (GIXRD) measurements. These measurements indicate a strong dependence of these process variations in secondary phase formation and accumulation. A possible reaction mechanism of CZTSe thin films was presented. In a preliminary optimization of both the SnSex partial pressure and the reactive annealing process, a solar cell with 7.26% efficiency has been fabricated.
