Hostname: page-component-77c89778f8-sh8wx Total loading time: 0 Render date: 2024-07-18T05:50:25.081Z Has data issue: false hasContentIssue false

Evolution of the Mobility Gap with Thickness in Hydrogen-Diluted Intrinsic Si:H Materials in the Phase Transition Region and Its Effect on p-i-n Solar Cell Characteristics

Published online by Cambridge University Press:  17 March 2011

R.J. Koval
Affiliation:
The Center for Thin Film Devices at Pennsylvania State University, University Park, PA 1680
J.M. Pearce
Affiliation:
The Center for Thin Film Devices at Pennsylvania State University, University Park, PA 1680
A.S. Ferlauto
Affiliation:
The Center for Thin Film Devices at Pennsylvania State University, University Park, PA 1680
R.W. Collins
Affiliation:
The Center for Thin Film Devices at Pennsylvania State University, University Park, PA 1680
C.R. Wronski
Affiliation:
The Center for Thin Film Devices at Pennsylvania State University, University Park, PA 1680
Get access

Abstract

Insights into the growth processes and evolution of microstructure in intrinsic hydrogenated silicon (Si:H) films obtained from real-time spectroscopic ellipsometry (RTSE) are extended to the characterization of the optoelectronic properties of the corresponding solar cells. To assess the effects of transition regions from the amorphous to mixed microcrystalline phases, cell structures with and without such regions at different depths in the i-layer from the p-contact have been investigated. Experimental results are presented that clearly demonstrate changes in the mobility gap, Eµ, of the materials as their microstructure evolves with thickness, further supporting the important effect of the hydrogen dilution ratio R (R[H2]/[SiH4]) on the transition between the amorphous and microcrystalline phases. Light J-V characteristics at room temperature and dark J-V characteristics at different temperatures were measured on p(a-SiC:H:B)-i(Si:H)-n(µc-Si:H:P) solar cell structures with i-layers of different thicknesses and R values. The mobility gaps of both the amorphous and microcrystalline intrinsic-layer materials as well as those of the transition layers are obtained from dark J(V,T) measurements. Using numerical simulation, both the light and the dark J-V characteristics are self-consistently modeled assuming sharp changes in the mobility gaps at the intrinsic layer transition thicknesses determined by RTSE.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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. Bennett, M., Rajan, K., and Kritikson, K., Conf. Record of the 23rd IEEE PVSC, (IEEE, NY 1993), p. 845.Google Scholar
2. Yang, J., Xu, X., and Guha, S., Mater. Res. Soc. Symp. Proc. 336, 669 (1994).10.1557/PROC-336-669Google Scholar
3. Lee, Y., Jiao, L., Liu, H., Lu, Z., Collins, R.W., and Wronski, C.R., Conf. Record of 25th IEEE PVSC, (IEEE, NY 1996), p. 1165.Google Scholar
4. Koh, J., Lee, Y., Fujiwara, H., Wronski, C.R., and Collins, R.W., Appl. Phys. Lett. 73, 1526 (1998).Google Scholar
5. Collins, R.W., and Yang, B.Y., J. Vac. Sci. Tech. B 7, 1155 (1989).Google Scholar
6. Koh, J., Ferlauto, A.S., Rovira, P.I., Koval, R.J., Wronski, C.R., and Collins, R.W., Journal of Non-Crystalline Solids 266–269, 43 (2000).Google Scholar
7. Kocka, J., Fejfar, A., Fojtik, P., Luterova, K., Pelant, I., Rezek, B., Stuchlikova, H., Stucklik, J., and Svrcek, V., Solar Energy Materials and Solar Cells 66, 61 (2001).Google Scholar
8. Ferlauto, A.S., Rovira, P.I., Koval, R.J., Wronski, C.R., and Collins, R.W., Mater. Res. Soc. Symp. Proc. (2000, in press).Google Scholar
9. Koval, R.J., Koh, J., Lu, Z., Lee, Y., Jiao, L., Collins, R.W., and Wronski, C.R., Mater. Res. Soc. Symp. Proc. 557, 263 (1999).Google Scholar
10. Collins, R.W., An, I., Fujiwara, H., Lee, J., Lu, Y., Koh, J., and Rovira, P.I., Thin Solid Films 313, 18 (1998).10.1016/S0040-6090(97)00764-5Google Scholar
11. McElheny, P.J., Arch, J.K., Lin, H.S., and Fonash, S.J., J. Appl. Phys. 64, 1254 (1988).Google Scholar
12. Jiao, L., Semoushikina, S., Lee, Y., Wronski, C.R., Mater. Res. Soc. Symp. Proc. 97, 233 (1997).10.1557/PROC-467-233Google Scholar
13. Wagner, H., personal communication.Google Scholar
14. Finger, F., Muller, J., Malten, C., and Wagner, H., Phil. Mag. B 77, 805 (1998).10.1080/13642819808214836Google Scholar
15. Wronski, C.R., Lee, S., Hicks, M., and Kumar, S., Phys. Rev. Lett. 63, 1420 (1989).Google Scholar
16. Bennett, M.S. and Arya, R.R., Solar Cells 18, 289 (1986).Google Scholar
17. Zhu, H. and Fonash, S., Mater. Res. Soc. Symp. Proc. 507, 395 (1998).Google Scholar
18. Pearce, J., Koval, R., Ferlauto, A., Collins, R.W., Wronski, C.R., Yang, J., and Guha, S., Appl. Phys. Lett. 77, 3090 (2000).10.1063/1.1323550Google Scholar
19. Koval, R.J., Pearce, J., Ferlauto, A., Collins, R.W., and Wronski, C.R., Conf. Record of the 28th IEEE PVSC, (2000, in press).Google Scholar
20. Siebke, F., Yata, S., Hishikawa, Y., and Tanaka, M., Mater. Res. Soc. Symp. Proc. 507, 517 (1998).Google Scholar