Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-18T04:28:13.922Z Has data issue: false hasContentIssue false

Buffer-layer Effect on Mixed-Phase Cells Studied by Micro-Raman and Photoluminescence Spectroscopy

Published online by Cambridge University Press:  21 March 2011

Andrea Hilchey
Affiliation:
Dept of Physics & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599
Chris Lawyer
Affiliation:
Dept of Physics & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599
Keda Wang
Affiliation:
Dept of Physics & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599
Daxing Han
Affiliation:
Dept of Physics & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599
Baojie Yan
Affiliation:
United Solar Ovonic Corporation, 1100 West Maple Road, Troy, MI 48084
Guozhen Yue
Affiliation:
United Solar Ovonic Corporation, 1100 West Maple Road, Troy, MI 48084
Jeffrey Yang
Affiliation:
United Solar Ovonic Corporation, 1100 West Maple Road, Troy, MI 48084
Subhendu Guha
Affiliation:
United Solar Ovonic Corporation, 1100 West Maple Road, Troy, MI 48084
Get access

Abstract

We use micro-Raman and photoluminescence (PL) spectroscopy to study the effects of an a-Si:H buffer layer at the i/p interface of the mixed-phase silicon solar cells. We find that the signature of the crystalline 520 cm−1 mode still appears on the Raman spectrum for the cells with a 100 Å thick a-Si:H buffer layer; but it completely disappears for cells with a 500 Å thick a-Si:H buffer layer. At 80 K, the PL spectral lineshape reflects the features of the electronic states in the band tails. The characteristics of the PL spectra of the mixed-phase cells are a narrower main band than the standard a-Si:H band and an extra low energy band from the grain boundary region. As the thickness of the a-Si:H buffer layer increases, the PL main band becomes broader, and the low energy band is depressed. We find that, after light soaking, the PL main band is slightly broadened for the cells with no a-Si:H buffer layer, almost no change for the cells with a 100 Å thick buffer layer, and a remarkable decrease in total PL intensity for the cells with a 500 Å thick buffer layer. In addition, the PL intensity of the defect band increases after light soaking for the cells with a 500 Å thick buffer layer, where light-induced defect generation in the a-Si:H buffer layer masks the changes in the mixed-phase intrinsic layer. The Raman and PL results are consistent with previous observations of the effect of an a-Si:H buffer layer on the performance and metastability against light soaking for mixed-phase solar cells.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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

REFERENCE

1. Lord, K., Yan, B., Yang, J., and Guha, S., Appl. Phys. Lett. 79, 3800 (2001).Google Scholar
2. Yang, J., Lord, K., Yan, B., Banerjee, A., Guha, S., Han, D., Wang, K., Mater. Res. Soc. Symp. Proc. 715, 601 (2002).Google Scholar
3. Baugh, Jonathan and Han, Daxing, Phys. Rev. B 66 (2002) 115203.Google Scholar
4. Yan, B., Yang, J., and Guha, S., Proc. of 3rd World Conf. on Photovoltaic Conversion, (Osaka, Japan, 2003), in press.Google Scholar
5. Owens, J. M., Han, D., Yan, B., Yang, J., Lord, K., and Guha, S., Mater. Res. Soc. Symp. Proc. 762, 339 (2003).Google Scholar
6. Staebler, D.L. and Wronski, C.R., Appl. Phys. Lett. 31, 292 (1977).Google Scholar
7. Yue, G., Yan, B., Yang, J., Lord, K., and Guha, S., Mater. Res. Soc. Symp. Proc. 762, 21 (2003).Google Scholar
8. Yan, B., Yue, G., Yang, J., Banerjee, A., and Guha, S., Mater. Res. Soc. Symp. Proc. 762, 309 (2003).Google Scholar
9. Yue, G., Han, D., Williamson, D.L., Yang, J., Lord, K. and Guha, S., Appl. Phys. Lett. 77, 31853187 (2000).Google Scholar
10. Yue, G., McNeil, L. E., Han, D., and Wang, Q., J. Appl. Phys. 88, 4940 (2000).Google Scholar
11. Yue, G., Lorentzen, J. D., Lin, J., Wang, Q. and Han, D., Appl. Phys. Lett. 75, 492494 (1999).Google Scholar