Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-29T09:19:08.121Z Has data issue: false hasContentIssue false

Tunability of Intrinsic Stress in Siox Dielectric Films Formed by Molecular Beam Deposition

Published online by Cambridge University Press:  21 February 2011

Naresh Chand
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
R. R. Kola
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
J. W. Osenbach
Affiliation:
AT&T Bell Laboratories, Breinigsville, PA 18031.
W. T. Tsang
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
Get access

Abstract

Silicon monoxide (SiO) formed by molecular beam deposition (MBD) has many attractive optical, electrical, mechanical, and chemical properties which make it a suitable dielectric for many semiconductor device applications. It can be thermally evaporated at a much lower temperature than Si, SiO2 or Si3 N4 and it condenses on cooler surfaces in uniform and adherent stoichiometric SiO (x = 1) films when evaporated in high vacuum. At low deposition rates and at high pressures of oxygen, SiOx (1 ≤ x ≤ 2) films result. This allows variation of refractive index, stress and other properties of SiOx with x. In general, the SiO (x = l) films are under tensile stress <100 MPa which is significantly lower than that observed in other dielectric films. Slight introduction of oxygen during deposition reduces the tensile stress; at an O2 pressure of 5 × 10−7 Torr and above, the films are in compression. This allows the tunability of stress in SiOx films and deposition of films essentially free from stress. Furthermore, both Si and SiO have similar values of the linear thermal expansion coefficient (average values between 23 °C and 350°C: 3.37 × 10−6°C−1 and 2.7 × 10−6°C−1, respectively). As a result, SiOx/Si films develop little thermal stress during thermal cycling.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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

1. Obeng, Y. S., Steiner, K. G., Velaga, A. N. and Pai, C-S., AT&T Tech. Journal 73, 94 (1994).Google Scholar
2. Flinn, P. A., Gardner, D. S. and Nix, W. D., IEEE Trans, on Electron Devices ED34, 689 (1987).Google Scholar
3. See various papers in Thin Films: Stresses and Mechanical Properties II, Doerner, M. F., Oliver, W. C., Pharr, G. M. and Brotzen, F. R., Eds., MRS Symposium Proceedings, vol. 188 (1990).Google Scholar
4. Bradford, A. P. and Hass, G., J. Opt. Soc. Am. 53, 1096 (1963).Google Scholar
5. Hass, G., J. Am. Ceramic Soc., 33, 353 (1950).Google Scholar
6. Hass, G. and Salzberg, C. D., J. Opt. Soc. Am. 44, 181 (1954).Google Scholar
7. Phillipp, H. P., J. Phys. Chem. Solids 32, 1935 (1971).Google Scholar
8. Priest, J., Caswell, H. L., and Budo, Y., J. Appl. Phys. 34, 347 (1963).Google Scholar
9. Eisenstein, G., Raybon, G. and Stulz, L. W., J. Lightwave Technol. 6, 12 (1988).Google Scholar
10. Saitoh, T., Mukai, T., and Mikami, O., J. Lightwave Technol. LT–3, 288 (1985).Google Scholar
11. Wu, I.-F., Dottellis, J. B., and Dagenais, M., J. Vac. Sci. Technol. A11, 2398 (1993).Google Scholar
12. Chand, N., Johnson, J. E., Liang, W. C., Feldman, L. C., Tsang, W. T., Krautter, H. W., Passlack, M., Hull, R., Osenbach, J. W., and Swaminathan, V., J. Crystal Growth, To be published.Google Scholar
13. Chand, N., Osenbach, J. W., Kola, R. R., Opila, R., Comizzoli, R. B., Krautter, H., Sergent, A. M., and Tsang, W. T., J. Appl. Phys., To be published.Google Scholar
14. Stoney, G. G., Proc. R. Soc. A82, 172 (1909).Google Scholar