Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-23T15:13:32.386Z Has data issue: false hasContentIssue false

Microscopic Measurements of Electrical Potential in Hydrogenated Nanocrystalline Silicon Solar Cells

Published online by Cambridge University Press:  15 June 2012

C.-S. Jiang
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
H.R. Moutinho
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
R.C. Reedy
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
M.M. Al-Jassim
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
B. Yan
Affiliation:
United Solar Ovonic LLC, Troy, MI 48084, USA
G. Yue
Affiliation:
United Solar Ovonic LLC, Troy, MI 48084, USA
L. Sivec
Affiliation:
United Solar Ovonic LLC, Troy, MI 48084, USA
J. Yang
Affiliation:
United Solar Ovonic LLC, Troy, MI 48084, USA
S. Guha
Affiliation:
United Solar Ovonic LLC, Troy, MI 48084, USA
X. Tong
Affiliation:
Brookhaven National Laboratory, Upton, NY 11973, USA
Get access

Abstract

We report on a direct measurement of electrical potential and field profiles across the n-i-p junction of hydrogenated nanocrystalline silicon (nc-Si:H) solar cells, using the nanometer-resolution potential imaging technique of scanning Kelvin probe force microscopy (SKPFM). It was observed that the electric field is nonuniform across the i layer. It is much higher in the p/i region than in the middle and the n/i region, illustrating that the i layer is actually slightly n-type. A measurement on a nc-Si:H cell with a higher oxygen impurity concentration shows that the nonuniformity of the electric field is much more pronounced than in samples having a lower O impurity, indicating that O is an electron donor in nc-Si:H materials. This nonuniform distribution of electric field implies a mixture of diffusion and drift of carrier transport in the nc-Si:H solar cells. The composition and structure of these nc-Si:H cells were further investigated by using secondary-ion mass spectrometry and Raman spectroscopy, respectively. The effects of impurity and structural properties on the electrical potential distribution and solar cell performance are discussed.

Type
Articles
Copyright
Copyright © Materials Research Society 2012

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

Schiff, E.A., Sol. Energy Mater. Sol. Cells 78, 567 (2003).CrossRefGoogle Scholar
Schiff, E.A., Mater. Res. Soc. Symp. Proc. 1153, 1151–A15 (2009).CrossRefGoogle Scholar
Fischer, D. and Shah, A.V., Appl. Phys. Lett. 65, 986 (1994).CrossRefGoogle Scholar
Dairiki, K., Yamada, A., and Konagai, M., Jpn. J. Appl. Phys. 40, 486 (2001).CrossRefGoogle Scholar
Nonnemacher, M., O’Boyle, M.P., and Wickramasinghe, H.K., Appl. Phys. Lett. 58, 2921 (1991).CrossRefGoogle Scholar
Jiang, C.-S., Moutinho, H.R., Reedy, R., Al-Jassim, M.M., and Blosse, A., J. Appl. Phys. 104, 104501 (2008).CrossRefGoogle Scholar
Jiang, C.-S., Ptak, A., Yan, B., Moutinho, H.R., Li, J.V., and Al-Jassim, M.M., Ultramicroscopy 109, 952 (2009).CrossRefGoogle Scholar
Yan, B., Yue, G., Yang, J., and Guha, S., Mater. Res. Soc. Symp. Proc. 989, 335 (2007).CrossRefGoogle Scholar
Yue, G., Yan, B., Sivec, L., Zhou, Y., Yang, J., and Guha, S., Sol. Energy Mater. Sol. Cells, submitted (2012).Google Scholar
Ammerlaan, C.A.J., in Properties of Crystalline Silicon, ed. Hull, R. (INSPEC, London, 1999), p.663.Google Scholar