Hostname: page-component-77c89778f8-sh8wx Total loading time: 0 Render date: 2024-07-17T14:41:41.116Z Has data issue: false hasContentIssue false

Tailoring the Structure of Low-Temperature-Deposited Microcrystalline Silicon Films by Biasing the Substrate

Published online by Cambridge University Press:  17 March 2011

Burkhardt Selle
Affiliation:
Hahn-Meitner-Institut Berlin, Silizium-Photovoltaik, Kekuléstr. 5, 12489 Berlin, GERMANY
Walther Fuhs
Affiliation:
Hahn-Meitner-Institut Berlin, Silizium-Photovoltaik, Kekuléstr. 5, 12489 Berlin, GERMANY
Don L. Williamson
Affiliation:
Colorado School of Mines, Department of Physics, Golden, CO 80401, USA
Get access

Abstract

Biasing the substrate during deposition and the substrate's surface morphology may both have major effects on the structural properties of thin films. We present the results of structural investigations (Raman and FTIR spectroscopy, XRD, SAXS) of thin silicon films that were prepared at low temperatures by electron-cyclotron resonance (ECR) chemical-vapor deposition. The effect of substrate bias during the deposition was investigated for positive DC susceptor biases VB ranging from 0 to 45 V. For stainless steel substrates with an artificially enlarged surface roughness (smart substrates), an increase of the crystallinity could be observed with Raman spectroscopy. Films prepared under a susceptor bias of +15 V exhibited a texture inversion of preferential (220)- to (111)- oriented grains, which was accompanied by an increase in grain size from 18 to 42 nm. Small-angle X-ray scattering (SAXS) revealed the films as deposited on Al foil to exhibit significant free volume fractions (microvoids). The ability of tailoring the structure of thin Si films by applying a bias is discussed in terms of controlling the energy and intensity of ion flux to the surface of the growing film. This can efficiently be achieved in an ECR system, where the mean free path of gas particles exceeds the thickness of the plasma sheath.

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. Shirai, K., Gonda, S., J. Appl. Phys. 68, 4258 (1990).Google Scholar
2. Nozawa, R., Takeda, H., Ito, M., Hori, M., Goto, T., J. Appl. Phys. 81, 8035 (1997).10.1063/1.365408Google Scholar
3. Tae, H.-S., Hwang, S.-H., Park, S.-J., Yoon, E., Whang, K.-W., J. Appl. Phys. 78, 4112 (1995).10.1063/1.359870Google Scholar
4. Platen-Schwarzkopf, J., Selle, B., Christiansen, S., Nerding, M., Schmidbauer, M., Kliefoth, K., Fuhs, W., Mat. Res. Soc. Symp. Proc. 609, 8.6 (2000).Google Scholar
5. Birkholz, M., Conrad, E., Fuhs, W., Jap. J. Appl. Phys., in press (2001).Google Scholar
6. Birkholz, M., Conrad, E., Lips, K., Selle, B., Sieber, I., Christiansen, S., Fuhs, W., Mat. Res. Soc. Symp. Proc. 609, 5.5 (2000).10.1557/PROC-609-A5.5Google Scholar
7. Kirk, C.T., Phys. Rev. B 38, 1255 (1988).10.1103/PhysRevB.38.1255Google Scholar
8. Brüesch, P., Stockmeier, T., Stucki, F., Buffat, P.A., Lindner, J.K.N., J. Appl. Phys. 73, 7690 (1993).10.1063/1.353966Google Scholar
9. Birkholz, M., Selle, B., Conrad, E., Lips, K., Fuhs, W., J. Appl. Phys. 88, 4376 (2000).Google Scholar
10. Williamson, D.L., Mat. Res. Soc. Symp. Proc. 377, 251 (1995).10.1557/PROC-377-251Google Scholar
11. Birkholz, M., Selle, B., Fuhs, W., Christiansen, S., Strunk, H.P., Reich, R., Phys. Rev. B, in press (2001)Google Scholar
12. Holber, W.M., J. Vac. Sci. Technol. A 8, 3720 (1990).Google Scholar
13. Hamers, E.A.G., Sark, W.v., Bezemer, J., Mailing, H., Weg, W.v.d., J. Non-Cryst. Sol. 226, 205 (1998).Google Scholar
14. Tae, H.-S., Park, S.-J., Hwang, S.-H., Hwang, K.-H., Yoon, E., Whang, K.-W., J. Vac. Sci. Technol. B 13, 908 (1995).10.1116/1.588204Google Scholar
15. Hamers, E.A.G., Morral, A. Fontcuberta i, Niikura, C., Brenot, R., Cabarrocas, P. Roca i, J. Appl. Phys. 88, 3674 (2000).10.1063/1.1289523Google Scholar
16. Abelmann, L., Lodder, C., Thin Sol. Films 305, 1 (1997).10.1016/S0040-6090(97)00095-3Google Scholar