Assessment of off-axis and in-line electron holography for measurement of potential variations in Cu(In,Ga)Se2 thin-film solar cells
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- 作者：Debora Keller ; Stephan Buecheler…
- 关键词：In ; line ; Off ; axis ; Holography ; Transport of intensity equation (TIE) ; Mean inner potential (MIP) ; Cu(In ; Ga)Se2 ; Chalcopyrite ; Solar cell
- 刊名：Advanced Structural and Chemical Imaging
- 出版年：2017
- 出版时间：January 2017
- 年：2017
- 卷：2
- 期：1
- 全文大小：5,180 KB
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Stephan Buecheler (1)
Patrick Reinhard (1)
Fabian Pianezzi (1)
Etienne Snoeck (3)
Christophe Gatel (3)
Marta D. Rossell (2)
Rolf Erni (2)
Ayodhya N. Tiwari (1)
1. Laboratory for Thin Films and Photovoltaics, Empa - Swiss Federal Laboratories for Materials Science and Technology, Ueberlandstrasse 129, 8600, Duebendorf, Switzerland
2. Electron Microscopy Center, Empa - Swiss Federal Laboratories for Materials Science and Technology, Ueberlandstrasse 129, 8600, Duebendorf, Switzerland
3. CNRS CEMES, 29, rue Jeanne Marvig, 31055, Toulouse, France - 刊物类别：Characterization and Evaluation of Materials; Spectroscopy/Spectrometry; Biological Microscopy;
- 刊物主题：Characterization and Evaluation of Materials; Spectroscopy/Spectrometry; Biological Microscopy;
- 出版者：Springer International Publishing
- ISSN：2198-0926
文摘
Electron holography is employed to study variations of the electrostatic crystal potential in Cu(In,Ga)Se2 (CIGS) thin-film solar cells at different length scales: Long-range potential variations across the layer structure of the solar cell as well as inhomogeneities within the layers are analyzed by off-axis holography. In-line holography is applied to examine the local potential variation across a CIGS grain boundary. The phase reconstruction from a focal series is performed by a modified transport of intensity equation (TIE) which is optimized to reduce common artifacts. For comparison, three different microscopes of different optical configurations were used for in-line holography. Based on the results, the impact of the used microscope as well as further acquisition parameters on the in-line holography measurement is assessed. The measured potential variations are discussed considering the effect of different possible sources that may cause potential fluctuations. It is found that most of the variations are best explained by mean inner potential fluctuations rather than by inhomogeneities of the electronic properties. Finally, the present resolution limit of both methods is discussed regarding the feasibility of future electronic characterization of CIGS by holography. Keywords In-line Off-axis Holography Transport of intensity equation (TIE) Mean inner potential (MIP) Cu(In,Ga)Se2 Chalcopyrite Solar cell