Fabrication of Cu2SnS3 thin film solar cells using Cu/Sn layered metallic precursors prepared by a sputtering process. (15th March 2017)

• Record Type: Journal Article
• Authors: Lee, Ju Yeon; Kim, In Young; Surywanshi, Mahesh P.; Ghorpade, Uma V.; Lee, Dong Seon; Kim, Jin Hyeok
• Is Part Of: Solar energy. Volume 145(2017)
• Page Start: 27
• Page End: 32
• Publication Date: 2017-03-15
• Subjects: Cu2SnS3 -- Thin film solar cells (TFSCs) -- Sputtering method -- Raman; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2016.09.041
• Languages: English
• ISSNs: 0038-092X

Abstract

Highlights: Cu2 SnS3 was prepared by annealing of sputtered Cu-Sn precursor in Sulfur atmosphere. The amount of S powder was varied. The optimized CTS thin film exhibited the highest efficiency of 2.21%. Abstract: As an alternative to Cu(In, Ga)(S, Se)2 (CIGS) and Cu2 ZnSn(S, Se)4 (CZTS)-based thin film solar cells (TFSCs), the ternary chalcogenide semiconductor Cu2 SnS3 (CTS) is an emerging material with suitable optical band gap energy ranging from 0.93 to 1.77 eV and high absorption coefficients (>10 4 cm −1 ). In this study, we report the preparation of high-quality CTS thin films by the annealing of the sputtered Cu-Sn metallic precursor under S vapor atmosphere in a graphite box using the RTA process. Furthermore, the influence of different S vapor partial pressures in the graphite box during annealing on the properties of the CTS thin films has been investigated systematically. It is observed that the properties and photovoltaic performance of the CTS thin films are strongly dependent on the S vapor partial pressure during annealing. The monoclinic crystal structure is observed from X-ray diffraction (XRD) of the (1 1 2), (2 2 0), and (3 1 2) planes, and it is further confirmed using Raman spectroscopy by the presence of Raman peaks at 295 and 354 cm −1 . The direct band gap energy is found to be 0.91 eV by extrapolation from external quantum efficiency (EQE) measurement of a CTS thin film annealed using 60 mg of S powder. The preliminary best power conversion efficiency (PCE) of 2.21% with a short circuit current density of 29.7 mA/cm 2, an open circuit voltage of 179.5 mV, and a fill factor of 41% have been obtained for a CTS thin film annealed using 60 mg of S powder, although the processing parameters have not been optimized.