Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-27T01:47:13.787Z Has data issue: false hasContentIssue false

Impact of thickness variation of the ZnO:Al window layer on optoelectronic properties of CIGSSe solar cells

Published online by Cambridge University Press:  07 July 2011

Jan Keller
Affiliation:
Energy and Semiconductor Research Laboratory, D-26111 Oldenburg, Germany
Martin Knipper
Affiliation:
Energy and Semiconductor Research Laboratory, D-26111 Oldenburg, Germany
Jürgen Parisi
Affiliation:
Energy and Semiconductor Research Laboratory, D-26111 Oldenburg, Germany
Ingo Riedel
Affiliation:
Energy and Semiconductor Research Laboratory, D-26111 Oldenburg, Germany
Thomas Dalibor
Affiliation:
AVANCIS GmbH & Co. KG, Otto-Hahn-Ring 6, D-81739 Munich, Germany
Alejandro Avellan
Affiliation:
AVANCIS GmbH & Co. KG, Otto-Hahn-Ring 6, D-81739 Munich, Germany
Get access

Abstract

We studied the thickness variation of equally doped ZnO:Al films used as conductive window layer in Cu(In,Ga)(Se,S)2 (CIGSSe) thin film solar cells. The IV-characteristics of solar cells with window layer thickness of d1=200nm exhibit a strong enhancement of the short-circuit current density JSC (ΔJSC = 3mA/cm2) as compared to samples with module-like ZnO:Al-film thickness (d2=1200nm). Accordingly, the quantum efficiency reveals the spectral regimes where the JSC-gain occurs. Moreover, current-voltage measurements reveal that the cells with thicker ZnO:Al exhibit slightly decreased open circuit voltage VOC. This finding can be assigned to a decreased net-doping density NA, which appears to be introduced by additional heat flux during the longer process time required for deposition of thicker ZnO:Al films. However, the improved efficiency of solar cells with thinner window layer comes along with an increase of the series resistance (RS) by almost a factor of 2, which will have consequences for the series connection of elements in a module. XRD-diffractograms and SEM cross-section imaging suggest that the enhanced RS in cells with thin ZnO:Al is not exclusively related to the thickness but is also due to a reduced (002)-texture and an elongated lateral charge carrier pathway.

Type
Research Article
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Green, M. A., Emery, K., Hishikawa, Y., and Warta, W., Progress in Photovoltaics: Research and Applications (2010).Google Scholar
2. Dhere, N. G., Solar Energy Materials and Solar Cells 95, pp. 277280 (2010).Google Scholar
3. Kieven, D., Chen, J., Klenk, R., Rissom, T., Tang, Y., and Lux-steiner, M. C., Progress in Photovoltaics: Research and Applications 18, pp. 209213 (2010).Google Scholar
4. Kluth, O., Rech, B., Houben, L., Wiedera, S., Schöpe, G., Benekinga, C., Wagner, H., Löffl, A., Schock, H.W., Thin Solid Films 351, pp. 247253 (1999).Google Scholar
5. Hagiwara, Y., Nakada, T., Kunioka, A., Sol. Energy Mater. Sol. Cells 67, pp. 267271 (2001).Google Scholar
6. Hegedus, S. S. and Shafarman, W. N., Progress in Photovoltaics: Research and Applications 12, pp. 155176 (2004).Google Scholar
7. Heller, R. and McGannon, J., J. Appl. Phys. 21, p. 1283 (1950)Google Scholar
8. Dasgupta, N. P., Neubert, S., Lee, W., Trejo, O., Lee, J.-R., and Prinz, F. B., Chemistry of Materials, pp. 47694775 (2010).Google Scholar
9. Lee, J.-H. and Park, B.-O., Thin Solid Films 24, pp. 9499 (2003).Google Scholar