Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-20T13:24:54.098Z Has data issue: false hasContentIssue false

A Comparative Study of Ti/Low-k HSQ (Hydrogen Silsesquioxane) and Ti/TEOS (Tetraethylorthosilicate) Structures at Elevated Temperatures

Published online by Cambridge University Press:  17 March 2011

Linghui Chen
Affiliation:
Department of Chemical, Bio and Materials Engineering, NSF Center for Low Power Electronics, Arizona State University, Tempe, Arizona 85287-6006, USA
T. L. Alford
Affiliation:
Department of Chemical, Bio and Materials Engineering, NSF Center for Low Power Electronics, Arizona State University, Tempe, Arizona 85287-6006, USA
Get access

Abstract

For the benefit of reducing capacitance in multilevel interconnect technology, low-k dielectric HSQ (hydrogen silsesquioxane) has been used as a gapfill material in Al-metallization- based non-etchback embedded scheme. The vias are consequently fabricated through the HSQ layer followed by W plug deposition. In order to reduce the extent of via poisoning and achieve good W/Al contact, thin Ti/TiN stack films are typically deposited before via plug deposition. In this case, HSQ makes direct contact with the Ti layer. The reliability of the Ti/HSQ structures at elevated temperatures has been systematically studied in this work by using a variety of techniques. These results are also compared with those from Ti/TEOS (Tetraethylorthosilicate) structure, where TEOS is a conventional intra-metal dielectric. When the temperature is below 550 °C, a significant number of oxygen atoms are observed to diffuse into the titanium layer. The primary source of oxygen is believed to come from the HSQ film. When the temperature is above 550 °C, HSQ starts to react with Ti. At 700 °C, a TiO/Ti5Si3/HSQ stack structure forms. The Ti/HSQ system exhibits a higher reactivity than that of the Ti/TEOS system.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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. Jeng, S.-P., Chang, M.-C., Kroger, T., McAnally, P., Havemann, R. H., VLSI Tech. Symp. Tech. Dig. 1994, p73.Google Scholar
2. Taylor, K. J., Eissa, M., Gaynor, J., Ngugen, H., Mat. Res. Soc. Sym. Proc. 476 (1997) 82.10.1557/PROC-476-197Google Scholar
3. Lee, W. W., Ho, P. S., MRS Bulletin 22 (1997) 19.10.1557/S0883769400034151Google Scholar
4. Jeng, S.-P., Taylor, K.J., Seha, T., Chang, M.-C., Fattaruso, J., Havemann, R. H., VLSI Tech. Symp. Kyoto, Japan, 1995, p61.Google Scholar
5. Bremmer, J. N., Liu, Y., Gruszynski, K. G., Dall, F. C., Mat. Res. Soc. Sym. Proc. 427 (1997) 103.Google Scholar
6. Chiang, C., Lam, N.V., Chu, J. K., Cox, N., Fraser, J., Bozarth, J., Mumford, B., V-MIC Conf. IEEE, 1987, p404.Google Scholar
7. Tompkins, H. G., Tracy, C., J. Vac. Sci. Technol. B 8 (1990) 558.10.1116/1.585009Google Scholar
8. Ting, C. Y., Wittmer, M., Lyer, S. S., Brodsky, S. B., J. Electrochem. Soc., 131 (1984) 2934.10.1149/1.2115445Google Scholar
9. Kuiper, A. E. T., Willemsen, M. F. C., Barbour, J. C., Appl. Surf. Sci. 35 (1988-1989) 186.10.1016/0169-4332(88)90048-7Google Scholar
10. Russell, S. W., Strane, J. W., Mayer, J. W., Wang, S.-Q., J Appl. Phys. 76 (1994) 257.10.1063/1.357137Google Scholar
11. Doolittle, L. R., Nucl. Instrum. Meth. B 9 (1985) 344.10.1016/0168-583X(85)90762-1Google Scholar
12. Zeng, Y., Russell, S. W., McKerrow, A. J., Chen, L.-H., Alford, T. L., J. Vac. Sci. Technol B 18 (2000) 221.10.1116/1.591176Google Scholar
13. Russell, S. W., Strane, J. W., Mayer, J.W., Wang, S.-Q., J Appl. Phys. 76 (1994) 264.10.1063/1.357139Google Scholar
14. Patnaik, B. K., C. V. Barros Leite, Baptista, G. B., Schweikert, E. A., Cocke, D. L., Quinones, L., Magussen, N., Nucl. Instrum. Meth. B 35 (1988) 159.10.1016/0168-583X(88)90488-0Google Scholar