Influence of Zinc Concentration and Sulfurization on the Physical Properties of CZTS Thin Films: Synthesis and Characterization

Document Type : Original Article


School of Physics, Damghan University, Damghan, IRAN


This study focused on the synthesis and characterization of CZTS thin films using a spray pyrolysis method followed by sulfurization. Three different samples were prepared by varying the molar ratios of zinc to tin: Cu2ZnSnS4 (PV), Cu2Zn0.9Sn1.1S4 (NC), and Cu2Zn1.1Sn0.9S4 (PC). The samples were annealed in the presence of sulfur at 300℃. X-ray diffraction (XRD) analysis revealed the formation of a kesterite crystal structure in all samples, with the (112) plane being the dominant orientation. The CZTS thin films showed a maximum crystallite size of 11.6 nm in the PC sample. Field emission scanning electron microscopy (FESEM) was used to investigate the morphological properties, providing insights into the surface characteristics and microstructure of the thin films. The optical properties of the CZTS thin films were examined using UV-Vis spectroscopy. It was observed that the band gap energy increased in all samples after sulfurization, ranging from 1.50 eV to 1.66 eV.  This indicates the potential suitability of the films as absorber layers in solar cell applications. The electrical properties were evaluated through Hall effect measurements, which revealed that the CZTS thin films exhibited p-type conductivity. The NC sample demonstrated the lowest specific resistivity of 1.43 Ω.cm.


Main Subjects

© 2023 The Author(s). Journal of Progress in Physics of Applied Materials published by Semnan University Press. This is an open access article under the CC-BY 4.0 license. (

[1] Khemiri, N., Chamekh, S. and Kanzari, M., 2020. Properties of thermally evaporated CZTS thin films and numerical simulation of earth abundant and non toxic CZTS/Zn (S, O) based solar cells. Solar Energy, 207, pp.496-502.
[2] Isotta, E., Syafiq, U., Ataollahi, N., Chiappini, A., Malerba, C., Luong, S., Trifiletti, V., Fenwick, O., Pugno, N.M. and Scardi, P., 2021. Thermoelectric properties of CZTS thin films: Effect of Cu–Zn disorder. Physical Chemistry Chemical Physics, 23(23), pp.13148-13158.
[3] Tanaka, K., Oonuki, M., Moritake, N. and Uchiki, H., 2009. Cu2ZnSnS4 thin film solar cells prepared by non-vacuum processing. Solar Energy Materials and Solar Cells, 93(5), pp.583-587.
[4] Xu, B., Qin, X., Lin, J., Chen, J., Tong, H., Qi, R., Yue, F., Chen, Y., Yang, P., Chu, J. and Sun, L., 2022. Positive role of inhibiting CZTSSe decomposition on intrinsic defects and interface recombination of 12.03% efficient kesterite solar cells. Solar RRL, 6(8), p.2200256.
[5] Islam, M.F., Yatim, N.M. and Hashim, M.A., 2021. A review of CZTS thin film solar cell technology. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 81(1), pp.73-87.
[6] Sayed, M.H., Schoneberg, J., Parisi, J. and Guetay, L., 2018. Influence of silver incorporation on CZTSSe solar cells grown by spray pyrolysis. Materials Science in Semiconductor Processing, 76, pp.31-36.
[7] Shockley, W. and Queisser, H., 2018. Detailed balance limit of efficiency of p–n junction solar cells. In Renewable Energy (pp. Vol2_35-Vol2_54). Routledge.
[8] Tanaka, K., Oonuki, M., Moritake, N. and Uchiki, H., 2009. Cu2ZnSnS4 thin film solar cells prepared by non-vacuum processing. Solar Energy Materials and Solar Cells, 93(5), pp.583-587.
[9] Deokate, R.J., Chavan, H.S., Im, H. and Inamdar, A.I., 2022. Spray-deposited kesterite Cu2ZnSnS4 (CZTS): Optical, structural, and electrical investigations for solar cell applications. Ceramics International, 48(1), pp.795-802.
[10] Wibowo, R.A., 2018. Powder-to-film approach for fabricating critical raw material-free kesterite Cu2ZnSn (S, Se) 4 thin film photovoltaic: A review. Solar Energy, 176, pp.157-169.
[11] Wright, L.D., Lowe, J.C., Bliss, M., Tsai, V., Togay, M., Betts, T.R., Walls, J.M., Malkov, A.V. and Bowers, J.W., 2019. Water based spray pyrolysis of metal-oxide solutions for Cu2ZnSn (S, Se) 4 solar cells using low toxicity amine/thiol complexants. Thin Solid Films, 669, pp.588-594.
[12] Bruc, L.I., Guc, M., Rusu, M., Sherban, D.A., Simashkevich, A.V., Shorr, S., Izquierdo-Roca, V., Pérez-Rodríguez, A. and Arushanov, E.K., 2012. Kesterite thin films of Cu2ZnSnS4 obtained by spray pyrolysis. In Proceedings of 27th European Photovoltaic Solar Energy Conference and Exhibition (pp. 2763-2766).
[13] Wang, K., Gunawan, O., Todorov, T., Shin, B., Chey, S.J., Bojarczuk, N.A., Mitzi, D. and Guha, S., 2010. Thermally evaporated Cu2ZnSnS4 solar cells. Applied Physics Letters, 97(14).
[14] Xie, M., Zhuang, D., Zhao, M., Zhuang, Z., Ouyang, L., Li, X. and Song, J., 2013. Preparation and characterization of Cu 2 ZnSnS 4 thin films and solar cells fabricated from quaternary Cu-Zn-Sn-S target. International Journal of Photoenergy, 2013.
[15] Singh, O.P., Muhunthan, N., Singh, V.N., Samanta, K. and Dilawar, N., 2014. Effect of temperature on thermal expansion and anharmonicity in Cu2ZnSnS4 thin films grown by co-sputtering and sulfurization. Materials Chemistry and Physics, 146(3), pp.452-455.
[16] Yeh, M.Y., Lee, C.C. and Wuu, D.S., 2009. Influences of synthesizing temperatures on the properties of Cu 2 ZnSnS 4 prepared by sol–gel spin-coated deposition. Journal of sol-gel science and technology, 52, pp.65-68.
[17] Kumar, S., Singh, P.K. and Chilana, G.S., 2009. Study of silicon solar cell at different intensities of illumination and wavelengths using impedance spectroscopy. Solar Energy Materials and Solar Cells, 93(10), pp.1881-1884.
[18] Kumar, Y.K., Bhaskar, P.U., Babu, G.S. and Raja, V.S., 2010. Effect of copper salt and thiourea concentrations on the formation of Cu2ZnSnS4 thin films by spray pyrolysis. physica status solidi (a), 207(1), pp.149-156.
[19] Nakayama, N. and Ito, K., 1996. Sprayed films of stannite Cu2ZnSnS4. Applied Surface Science, 92, pp.171-175.
[20] Kumar, Y.K., Babu, G.S., Bhaskar, P.U. and Raja, V.S., 2009. Preparation and characterization of spray-deposited Cu2ZnSnS4 thin films. Solar Energy Materials and Solar Cells, 93(8), pp.1230-1237.
[21] Kameyama, T., Osaki, T., Okazaki, K.I., Shibayama, T., Kudo, A., Kuwabata, S. and Torimoto, T., 2010. Preparation and photoelectrochemical properties of densely immobilized Cu 2 ZnSnS 4 nanoparticle films. Journal of Materials Chemistry, 20(25), pp.5319-5324.
[22] Stanchik, A.V., Gremenok, V.F., Juskenas, R., Tyukhov, I.I., Tivanov, M.S., Fettkenhauer, C., Shvartsman, V.V., Giraitis, R., Hagemann, U. and Lupascu, D.C., 2019. Effects of selenization time and temperature on the growth of Cu2ZnSnSe4 thin films on a metal substrate for flexible solar cells. Solar Energy, 178, pp.142-149.
[23] Park, H., Hwang, Y.H. and Bae, B.S., 2013. Sol–gel processed Cu 2 ZnSnS 4 thin films for a photovoltaic absorber layer without sulfurization. Journal of sol-gel science and technology, 65, pp.23-27.
[24] Ko, B.S., Kim, J.S., Jeon, D.H., Kang, J.K. and Hwang, D.K., 2018. Effects of back annealing on the structural and electrical properties of Cu2ZnSnSe4 thin films grown by a modified two-step process. Science of Advanced Materials, 10(4), pp.580-585.
[25] Benaicha, M., Hamla, M. and Derbal, S., 2016. Electrochemical formation and selenization of ternary CuZnSn alloys for growing Cu2ZnSnSe4 photoactive thin films. International Journal of Electrochemical Science, 11(6), pp.4909-4921.
[26] Abusnina, M., Moutinho, H., Al-Jassim, M., DeHart, C. and Matin, M., 2014. Fabrication and characterization of CZTS thin films prepared by the sulfurization of RF-sputtered
stacked metal precursors. Journal of electronic materials, 43, pp.3145-3154.