Numerical Optimization of a CZTS Thin-Film Solar Cell for Enhanced Photovoltaic Performance Using SCAPS-1D

• Wafaa F. Gebril

  Department of Physics, Faculty of Science-Almarj, University of Benghazi, Almarj, Libya

  Author

Earth-abundant and non-toxic copper zinc tin sulfide (Cu2ZnSnS4, CZTS) serves as a compelling absorber candidate for thin-film solar technology, characterized by a favorable direct optical bandgap near 1.5 eV alongside a strong absorption coefficient. This work presents a numerical simulation of an ITO ZnO CdS CZTS Mo heterojunction configuration carried out via the SCAPS-1D platform under ambient conditions (300 K) and standard AM1.5G solar spectrum (100 mW cm²). Key physical parameters, including the spatial dimensions of the CZTS absorber, ZnO window, and CdS buffer layers, alongside acceptor doping densities and working temperatures, were systematically varied to evaluate device characteristics. Findings demonstrate that increasing the CZTS absorber thickness enhances the photovoltaic response up to an optimum thickness of 2.4 μm, beyond which only a limited additional improvement is obtained. The ZnO thickness has a comparatively minor influence on the simulated performance over the investigated range; therefore, a thickness of 50 nm was selected as a practical value while maintaining near-maximum efficiency. The absorber acceptor concentration strongly affects the device characteristics, with an optimum practical value of NA=1×10¹⁸ cm^-3 identified for the investigated structure. Following optimization of the selected device parameters, the proposed solar cell achieves a maximum power conversion efficiency of 24.19%, with an open-circuit voltage V_oc of 1.057 V, a short-circuit current density J_sc of 26.18 mA cm^-2, and a fill factor FF of 87.42%. These outcome metrics confirm that comprehensive physical and electrical calibration across the absorber, buffer, and window regions significantly boosts the simulated efficiency of thin-film CZTS heterojunction devices.

Ait Abdelkadir, A., & Sahal, M. (2023). Theoretical development of the CZTS thin-film solar cell by SCAPS-1D software based on experimental work. Materials Science and Engineering: B, 296, Article 116710. https://doi.org/10.1016/j.mseb.2023.116710 DOI: https://doi.org/10.1016/j.mseb.2023.116710

Alhammadi, S., Park, H., & Kim, W. K. (2019). Optimization of intrinsic ZnO thickness in Cu(In,Ga)Se₂-based thin film solar cells. Materials, 12(9), Article 1365. https://doi.org/10.3390/ma12091365 DOI: https://doi.org/10.3390/ma12091365

Armstrong, R. C., Wolfram, C., de Jong, K. P., Gross, R., Lewis, N. S., Boardman, B., ... Yano, J. (2016). The frontiers of energy. Nature Energy, 1, Article 15020. https://doi.org/10.1038/nenergy.2015.20 DOI: https://doi.org/10.1038/nenergy.2015.20

Belarbi, F., Matur, U. C., Tamin, C., Rahal, W., Benghabrit, S., Baydogan, N., & Adnane, M. (2023). Experimental study and numerical simulation for the development of critical performance parameters of eco-friendly Cu₂ZnSnS₄-based solar cells. Optics & Laser Technology, 158, Article 108800. https://doi.org/10.1016/j.optlastec.2022.108800 DOI: https://doi.org/10.1016/j.optlastec.2022.108800

Benzetta, A. E., Abderrezek, M., & Djeghlal, M. E. (2021). Numerical study of CZTS/CZTSSe tandem thin film solar cell using SCAPS-1D. Optik, 242, Article 167320. https://doi.org/10.1016/j.ijleo.2021.167320 DOI: https://doi.org/10.1016/j.ijleo.2021.167320

Burgelman, M., Nollet, P., & Degrave, S. (2000). Modelling polycrystalline semiconductor solar cells. Thin Solid Films, 361–362, 527–532. https://doi.org/10.1016/S0040-6090(99)00825-1 DOI: https://doi.org/10.1016/S0040-6090(99)00825-1

Chen, J., Xu, B., Ma, H., Tong, H., Zou, L., Yang, P., Chu, J., Sun, L., & Chen, Y. (2024). Enhanced the performance of CZTSSe solar cells by optimized i:ZnO window layer. Materials Science in Semiconductor Processing, 171, Article 107993. https://doi.org/10.1016/j.mssp.2023.107993 DOI: https://doi.org/10.1016/j.mssp.2023.107993

Ellmer, K. (2012). Past achievements and future challenges in the development of optically transparent electrodes. Nature Photonics, 6(12), 809–817. https://doi:10.1038/nphoton.2012.282 DOI: https://doi.org/10.1038/nphoton.2012.282

Haegel, N. M., Atwater, H., Barnes, T., Breyer, C., Burrell, A., Chiang, Y.-M., ... Glunz, S. (2019). Terawatt-scale photovoltaics: Transform global energy. Science, 364(6443), 836–838. https://doi.org/10.1126/science.aaw1845 DOI: https://doi.org/10.1126/science.aaw1845

Intal, D., & Ebong, A. U. (2026). Thin-film solar photovoltaics: Trends and future directions. Renewable and Sustainable Energy Reviews, 226, Article 116464. https://doi.org/10.1016/j.rser.2025.116464 DOI: https://doi.org/10.1016/j.rser.2025.116464

Katagiri, H., Jimbo, K., Maw, W. S., Oishi, K., Yamazaki, M., Araki, H., & Takeuchi, A. (2009). Development of CZTS-based thin film solar cells. Thin Solid Films, 517(7), 2455–2460. https://doi.org/10.1016/j.tsf.2008.11.002. DOI: https://doi.org/10.1016/j.tsf.2008.11.002

Kumar, M., Dubey, A., Adhikari, N., Venkatesan, S., & Qiao, Q. (2015). Strategic review of secondary phases, defects and defect-complexes in kesterite CZTS–CZTSSe solar cells. Energy & Environmental Science, 8(11), 3134–3159. https://doi.org/10.1039/C5EE02153G DOI: https://doi.org/10.1039/C5EE02153G

Lai, C.-K., & Lin, Y.-C. (2024). Numerical investigation and device architecture optimization of Sb₂Se₃ thin-film solar cells using SCAPS-1D. Materials, 17(24), Article 6203. https://doi.org/10.3390/ma17246203 DOI: https://doi.org/10.3390/ma17246203

Liu, B., Guo, J., Hao, R., Liu, X., et al. (2019). Effect of ZnO intermediate layer thickness on performance of Cu₂ZnSnS₄ solar cells. Journal of Electronic Materials, 48(8), 1–7. https://doi.org/10.1007/s11664-019-07284-6 DOI: https://doi.org/10.1007/s11664-019-07284-6

Park, S. H., Crossay, A., & Naghavi, N. (2020). Transparent conductive oxides for thin film solar cells: Properties and applications. IEEE Journal of Photovoltaics, 10(3), 710–721. https://doi.org/10.1109/JPHOTOV.2020.2978120

Ranjan, R., Anand, N., Tripathi, M. N., Srivastava, N., Sharma, A. K., Yoshimura, M., Chang, L., & Tiwari, R. N. (2023). SCAPS study on the effect of various hole transport layer on highly efficient 31.86% eco-friendly CZTS based solar cell. Scientific Reports, 13, Article 18411. https://doi.org/10.1038/s41598-023-44845-6 DOI: https://doi.org/10.1038/s41598-023-44845-6

Sahu, S., Bais, B., & Santhosh, M. (2021). Optimization of CZTS based solar cell using SCAPS-1D. Optical and Quantum Electronics, 53(10), Article 592. https://doi.org/10.1007/s11082-021-03225-8

Scragg, J. J., Wätjen, J. T., Edoff, M., Ericson, T., Kubart, T., & Platzer-Björkman, C. (2012). A detrimental reaction at the molybdenum back contact in Cu₂ZnSn(S,Se)₄ thin-film solar cells. Journal of the American Chemical Society, 134(47), 19330–19333. https://doi:10.1021/ja308862n DOI: https://doi.org/10.1021/ja308862n

Siebentritt, S. (2013). Why are kesterite solar cells not 20% efficient? Thin Solid Films, 535, 1–4. https://doi.org/10.1016/j.tsf.2012.12.089 DOI: https://doi.org/10.1016/j.tsf.2012.12.089

Sivula, K., & van de Krol, R. (2016). Semiconducting materials for photoelectrochemical energy conversion. Nature Reviews Materials, 1, Article 15010. https://doi.org/10.1038/natrevmats.2015.10 DOI: https://doi.org/10.1038/natrevmats.2015.10

Sultan, M. Z., Shahriar, A., Tota, R., Howlader, M. N., Rodro, H. H., Akhy, M. J., & Rashik, M. A. A. (2024). Numerical study and optimization of CZTS-based thin-film solar cell structure with different novel buffer-layer materials using SCAPS-1D software. Energy and Power Engineering, 16(4), 179–195. https://doi.org/10.4236/epe.2024.164009 DOI: https://doi.org/10.4236/epe.2024.164009

Suryawanshi, M. P., Agawane, G. L., Bhosale, S. M., Shin, S. W., Patil, P. S., Kim, J. H., & Moholkar, A. V. (2013). CZTS based thin film solar cells: A status review. Materials Technology, 28(1–2), 98–109. https://doi.org/10.1179/1753555712Y.0000000038 DOI: https://doi.org/10.1179/1753555712Y.0000000038

Wei, H., Li, Y., Cui, C., Wang, X., Shao, Z., Pang, S., & Cui, G. (2023). Defect suppression for high-efficiency kesterite CZTSSe solar cells: Advances and prospects. Chemical Engineering Journal, 462, Article 142121. https://doi.org/10.1016/j.cej.2023.142121 DOI: https://doi.org/10.1016/j.cej.2023.142121

Zhang, S., Fan, L., Yao, D., Wu, J., Guo, H., Wang, H., & Zhang, Y. (2021). Band alignment tuning at Mo/CZTS back contact interface through surface oxidation states control of Mo substrate. Solar Energy Materials and Solar Cells, 229, Article 111141. https://doi.org/10.1016/j.solmat.2021.111141 DOI: https://doi.org/10.1016/j.solmat.2021.111141

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