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Process Optimization and Integration of HFO2 and HF-Silicates

Published online by Cambridge University Press:  28 July 2011

Hideki Takeuchi  and
Tsu-Jae King
Hideki Takeuchi
Affiliation:
Department of Electrical Engineering and Computer SciencesUniversity of California, Berkeley Berkeley, CA 94720-1770, U.S.A.
Tsu-Jae King
Affiliation:
Department of Electrical Engineering and Computer SciencesUniversity of California, Berkeley Berkeley, CA 94720-1770, U.S.A.
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Abstract

We have established in-line characterization techniques for analyzing the bulk and interface-charge properties of dielectric films, for process optimization. Surface charge analysis (SCA) is used to determine the densities of interface states, fixed charge, and near-interface traps in ultra-thin dielectrics, and is useful for tracking the influence of post-deposition processing on interface-charge properties. Spectroscopic ellipsometry (SE) is used to obtain the absorption spectra in the conduction band-tail region. The intensity of an extra absorption peak inside the bandgap of HfO2 is clearly correlated with leakage current density and near-interface trap density. Based on the observed process dependencies, defects within the HfO2 films are likely to be oxygen vacancies. The relative scalability of HfO2 and Hf-silicate films of various compositions is examined using a figure of merit based on the direct-tunneling leakage current model. Pure HfO2 is expected to be more scalable than Hf-silicates. However, it is typically accompanied by an interfacial layer which significantly increases the equivalent oxide thickness (EOT). A 20% Hf silicate with relative permittivity of 11 or higher can be more scalable than HfO2 with an interfacial layer. Alternatively, an ultra-thin interfacial Si3N4 diffusion barrier can be used with HfO2, to allow for more aggressive EOT scaling. The dependencies of interface-charge properties and surface roughness on the nitride barrier formation process are presented.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 811: Symposia D/E – Integration of Advanced Micro-and Nanelectronic Devices-Critical Issues and Solutions , 2004 , D7.6
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

[1] Wakabayashi, H. et al. , IEDM Tech Dig., p.989 (2003).Google Scholar
[2] ITRS 2002, http://public.itrs.net/.Google Scholar
[3] Lee, S.J. et al. , IEDM Tech Dig., p.31 (2000).Google Scholar
[4] Kang, L., et al. , IEDM Tech Dig., p.35 (2000).Google Scholar
[5] Lee, B.H., et al. , IEDM Tech Dig., p.39 (2000).Google Scholar
[6] Chau, R., AVS Fifth Intnl. Conf. on Microelctronice and Interfaces, p.1 (2004).Google Scholar
[7] Quevedo-Lopez, M., et al. , Appl. Phys. Lett., 79, p.4192 (2001).Google Scholar
[8] Onishi, K., et al. , Symp. on VLSI Tech., p.22 (2002).Google Scholar
[9] Kim, H., et al. , Appl. Phys. Lett., 82, p.106 (2003).Google Scholar
[10] Quevedo-Lopez, M., et al. , Appl. Phys. Lett., 82, p.1609 (2002).Google Scholar
[11] Hobbs, C., et al. , Symp. on VLSI Tech., p.9 (2003).Google Scholar
[12] Kim, Y., et al. , Symp. on VLSI Tech., p.167 (2003).Google Scholar
[13] Kauerauf, T., et al. , IEDM Tech Dig., p.521 (2002).Google Scholar
[14] Cho, M., Appl. Phys. Lett., 81, p.334 (2002).Google Scholar
[15] Koyama, M., et al. , IEDM Tech Dig., p.849 (2002).Google Scholar
[16] Qi, W-J., et al. , Symp. on VLSI Tech., p.40 (2000).Google Scholar
[17] Zhu, W., et al. , IEDM Tech Dig., p.463 (2001).Google Scholar
[18] Takeuchi, H., et al. , J. Electrochem. Soc., 151, p.H44 (2004).Google Scholar
[19] SemiTest Inc., Application Note #102 (1997).Google Scholar
[20] SemiTest Inc., SCA-2500 User Manual (2000).Google Scholar
[21] Sze, S. M., Physics of Semiconductor Devices, 2nd ed. (Wiley, New York, 1981).Google Scholar
[22] Onishi, K., et al. , Symp. VLSI Tech., p.22, (2002).Google Scholar
[23] Takeuchi, H., et al. , to appear in J. Vac. Sci. Tech. A (2004)Google Scholar
[24] Degraeve, R., et al. , IEDM Tech Dig., p.935 (2003).Google Scholar
[25] Shimiuzu, K., et al. , J. Appl. Phys.., 74, p. 375 (1993)Google Scholar
[26] Sawada, H., et al. , J. Appl. Phys.., 86, p. 956 (1999)Google Scholar
[27] Cho, Y. J., et al. , Appl. Phys. Lett., 82, p.1249 (2002)Google Scholar
[28] Robertson, J., J. Vac. Sci. Tech. B, 18, p.1785 (2000)Google Scholar
[29] Zhu, W., et al. , IEDM Tech Dig, p.463 (2001)Google Scholar
[30] Lucovsky, G., et al. , Appl. Phys. Lett., 79, p. 1775 (2001)Google Scholar
[31] Yu, P. Y., and Cardona, M., Fundamentals of Semiconductors: Physics and Material Properties, 2nd ed., (Springer, New York, 1996)Google Scholar
[32] Takeuchi, H., et al. , Appl. Phys. Lett., 83, p. 788 (2003)Google Scholar
[33] Lee, W.-C., et al. , IEEE Trans. Elect Dev. 48, p.1366 (2001)Google Scholar
[34] Yeo, Y.-C., et al. , IEEE Elect Dev. Lett., 21, p.540 (2000)Google Scholar
[35] Yeo, Y.-C., et al. , Appl. Phys. Lett., 81, p.2091 (2002)Google Scholar
[36] Krieger, G., et al. , J.Appl. Phys., 52, p..5710 (1982)Google Scholar
[37] Weinberg, Z. A., J. Appl. Phys., 53, p.5052 (1982)Google Scholar
[38] Kato, H., et al. , J. Appl. Phys., 92, p.1106 (2002)Google Scholar
[39] Callegari, A., et al. , J. Appl. Phys., 90, p.6466 (2001)Google Scholar
[40] Lucovsky, G., et al. , IEDM Tech Dig., p.617 (2002)Google Scholar
[41] Shanware, A., et al. , IEDM Tech Dig., p.137 (2001)Google Scholar
[42] Harada, Y., et al. , Symp. on VLSI Tech, p.26, (2002)Google Scholar
[43] Maria, J.-P., et al. , J. Mater. Res., 17, p.1571 (2002)Google Scholar
[44] Wilk, G. D., et al. , J. Appl. Phys., 87, p.484 (2000)Google Scholar
[45] Polishchuk, I., et al. , Dev. Res. Conf., p.105 (2002)Google Scholar
[46] Buchheit, K. M., et al. , MRS Fall meeting, E2.2 (2003)Google Scholar
[47] Lu, Q., et al. , IRPS, p.377 (2002).Google Scholar
[48] Hori, T., et al. , IEEE Trans on Elect. Dev., ED-34(11), p.2238 (1987)Google Scholar