Chemical and Electronic Structure of the i‐ZnO/In<sub>x</sub>S<sub>y</sub>:Na Front Contact Interface in Cu(In,Ga)(S,Se)<sub>2</sub> Thin‐Film Solar Cells
Abstract The chemical and electronic structure of the front contact i‐ZnO/In x S y :Na interface for Cu(In,Ga)(S,Se) 2 ‐based thin‐film solar cells is investigated using a combination of x‐ray and electron spectroscopies. Upon i‐ZnO sputter deposition on the In x S y :Na buffer layer, we find an intermixed heterojunction and the formation of InO x and Na 2 SO 4 . The window layer is shown to consist of a mixture of Zn(OH) 2 and ZnO, with decreasing relative Zn(OH) 2 content for thicker window layers. Moreover, we observe diffusion of sodium to the surface of the window layer. We derive electronic surface band gaps of the i‐ZnO and In x S y :Na layers of 3.86 ± 0.18 eV and 2.60 ± 0.18 eV, respectively, and find a largely flat conduction band alignment at the i‐ZnO/In x S y :Na interface.
Authors
- Thomas Dalibor (ORCID: https://orcid.org/0000-0003-1178-6793)
- Clemens Heske (ORCID: https://orcid.org/0000-0001-7586-4549)
- A. Benkert
- L. Weinhardt (ORCID: https://orcid.org/0000-0003-3361-1054)
- Monika Blum (ORCID: https://orcid.org/0000-0002-2918-9092)
- Wanli Yang (ORCID: https://orcid.org/0000-0003-0666-8063)
- Dirk Hauschild (ORCID: https://orcid.org/0000-0001-9088-8944)
- F. Reinert (ORCID: https://orcid.org/0000-0001-7993-1171)
- F. Meyer
Institutions
- Karlsruhe Institute of Technology (DE)
- University of Nevada, Las Vegas (US)
- Lawrence Berkeley National Laboratory (US)
- University of Würzburg (DE)
- Fraunhofer Institute for Mechanics of Materials (DE)
Publication Details
- Journal
- Progress in Photovoltaics Research and Applications
- Published
- 2024-08-23
- DOI
- https://doi.org/10.1002/pip.3840
- Primary Topic
- Chalcogenide Semiconductor Thin Films
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- U.S. Department of Energy
- Office of Science