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Characterization of Chemical Bonding in Low-K Dielectric Materials for Interconnect Isolation: A XAS and EELS Study

Published online by Cambridge University Press:  01 February 2011

Patrick Hoffmann ,
Dieter Schmeisser ,
Hans-Juergen Engelmann ,
Ehrenfried Zschech ,
Heiko Stegmann ,
Franz Himpsel  and
Jonathan Denlinger
Patrick Hoffmann
Affiliation:
[email protected], Brandenburg Technical University of Cottbus, Chair of Applied Physics II, Konrad-Wachsmann-Allee 17, Cottbus, N/A, 03046, Germany, +49 (0)355 69-2998, +49 (0)355 69-3931
Dieter Schmeisser
Affiliation:
[email protected], Brandenburg Technical University of Cottbus, Chair of Applied Physics II, Konrad-Wachsmann-Allee 17, Cottbus, N/A, 03046, Germany
Hans-Juergen Engelmann
Affiliation:
[email protected], AMD Saxony LLC & Co KG, Dresden, N/A, N/A, Germany
Ehrenfried Zschech
Affiliation:
[email protected], AMD Saxony LLC & Co KG, Dresden, N/A, N/A, Germany
Heiko Stegmann
Affiliation:
[email protected], Carl Zeiss NTS GmbH, Oberkochen, N/A, N/A, Germany
Franz Himpsel
Affiliation:
[email protected], Carl Zeiss NTS GmbH, Oberkochen, N/A, N/A, Germany
Jonathan Denlinger
Affiliation:
[email protected], University of Wisconsin / Madison, Madison, Wisconsin, 53706, United States
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Abstract

The use of low dielectric constant materials in the on-chip interconnect process reduces interconnect delay, power dissipation and crosstalk noise. To achieve the requirements of the ITRS for 2007-2009 minimal sidewall damage from etch, ash or cleans is required. In chemical vapor deposited (CVD) organo-silicate glass (OSG) which are used as intermetal dielectric (IMD) materials the substitution of oxygen in SiO2 by methyl groups (-CH3) reduces the permit-tivity significantly (from 4.0 in SiO2 to 2.6-3.3 in the OSG), since the electronic polarizability is lower for Si-C bonds than for Si-O bonds.

However, plasma processing for resist stripping, trench etching and post-etch cleaning removes C and H containing molecular groups from the near-surface layer of OSG. Therefore, compositional analysis and chemical bonding characterization of structured IMD films with nanometer resolution is necessary for process optimization.

OSG thin films as-deposited and after plasma treatment are studied using X-ray absorp-tion spectroscopy (XAS) and electron energy loss spectroscopy (EELS). In both techniques, the fine structure near the C1s absorption or energy loss edge, respectively, allows to identify C-H, C-C, and C-O bonds. This gives the opportunity to differentiate between individual low-k mate-rials and their modifications. The O1s signal is less selective to individual bonds. XAS spectra have been recorded for non-patterned films and EELS spectra for patterned structures. The chemical bonding is compared for as-deposited and plasma-treated low-k materials. The Fluo-rescence Yield (FY) and the Total Electron Yield (TEY) recorded while XAS measurement are compared. Examination of the C 1s near-edge structures reveal a modified bonding of the re-maining C atoms in the plasma-treated sample regions.

Keywords

dielectricx-ray fluorescenceelectron energy loss spectroscopy (EELS)
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 914: Symposium F – Materials, Technology and Reliability of Low-k Dielectrics and Copper Interconnects , 2006 , 0914-F01-08
Copyright
Copyright © Materials Research Society 2006

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References

1 Maier, G., Prog. in Polym. Sci. 26, 3–65 (2001).Google Scholar
2 Schulze, K., Schuldt, U., Kahle, O., Schulz, S.E., Uhlig, M., Uhlig, C., Dreyer, C., Bauer, M., Gessner, T., Microel.Engin. 82 356–361 (2005)Google Scholar
3 Lee, B.D., YPark, .H., Hwang, Y.T., Oh, W., Yoon, J., Ree, M., Nature Materials 4, 147 (2005).Google Scholar
4 Gosset, L.G., Arnal, V., Brun, P., Broekaart, M., Monget, C., Casanova, N., Rivoire, M., Oberlin, J.C., Torres, J., Microel. Engin. 70, 274 (2003).Google Scholar
5 Torquato, S., Donev, A., Evans, A.G., Brinker, C.J., J.Appl.Phys. 97, 395 (2005).Google Scholar
6 Maex, K., Baklanov, M.R., Shamiryan, D., Iacopi, F., Brongersma, S.H., Yanovitskaya, Z.S., J.Appl.Phys. 93, 8793–8841 (2003).Google Scholar
7 Hermann, H., Elsner, A., Hecker, M., Stoyan, D., Microel.Engin. 81, 535 (2005).Google Scholar
8 Yonekura, K., Sakamori, S., Goto, K., Matsuura, M., Fujiwara, N., Yoneda, M., J.Vac.Sci.Technol. B 22, 548 (2004).Google Scholar
9 Zschech, E., Stegmann, H., Hoffmann, P., Schmeisser, D., Potapov, P., Engelmann, H.-J., Chumakov, D., Geisler, H., Mater.Res.Soc.Proc., this volume.Google Scholar
10 Stegmann, H., Zschech, E. AIP Conf.Proc. 788, 549 (2005).Google Scholar
11 Ade, H., Urquhart, S., “NEXAFS Spectroscopy and Microscopy of Natural and Synthetic Polymers”, Chemical Applications of Synchrotron Radiation, editor Sham, Tsun-Kong (World Scientific Publishing Company, Singapore, July 2002) 285.Google Scholar
12 Wühn, M., Weckesser, J., Wöll, Ch., Langmuir 17, 7605 (2001).Google Scholar