Flexible kesterite thin-film solar cells under stress

Ha Kyung Park, Yunae Cho, Juran Kim, Sammi Kim, Sungjun Kim, Jeha Kim, Kee Jeong Yang, Dae Hwan Kim, Jin Kyu Kang, William Jo

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


Understanding the stress-induced phenomena is essential for improving the long-term application of flexible solar cells to non-flat surfaces. Here, we investigated the electronic band structure and carrier transport mechanism of Cu2ZnSn(S,Se)4 (CZTSSe) photovoltaic devices under mechanical stress. Highly efficient flexible CZTSSe devices were fabricated controlling the Na incorporation. The electronic structure of CZTSSe was deformed with stress as the band gap, valence band edge, and work function changed. Electrical properties of the bent CZTSSe surface were probed by Kelvin probe force microscopy and the CZTSSe with Na showed less degraded carrier transport compared to the CZTSSe without Na. The local open-circuit voltage (VOC) on the bent CZTSSe surface decreased due to limited carrier excitation. The reduction of local VOC occurred larger with convex bending than in concave bending, which is consistent with the degradation of device parameters. This study paves the way for understanding the stress-induced optoelectronic changes in flexible photovoltaic devices.

Original languageEnglish
Article number91
Journalnpj Flexible Electronics
Issue number1
StatePublished - Dec 2022

Bibliographical note

Funding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2018R1A6A1A03025340) and Ministry of Science, Technology, ICT, and Future Planning (NRF-2021R1A2B5B02001961). This research was supported by the program of Phased development of carbon neutral technologies through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (NRF-2022M3J1A1064229). Additionally, this work was supported by the DGIST R&D programs of the Ministry of Science and ICT (22-CoE-ET-01). The first author, H.K. Park, is also grateful for the financial support received from the Hyundai Motor Chung Mong-Koo Foundation.

Publisher Copyright:
© 2022, The Author(s).


Dive into the research topics of 'Flexible kesterite thin-film solar cells under stress'. Together they form a unique fingerprint.

Cite this