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Atomic Structure of β-Tantalum Nanocrystallites

Published online by Cambridge University Press:  15 November 2005

Karsten Tillmann
Affiliation:
Ernst Ruska-Centrum für Mikroskopie und Spektroskopie mit Elektronen, D-52425 Jülich, Germany Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
Andreas Thust
Affiliation:
Ernst Ruska-Centrum für Mikroskopie und Spektroskopie mit Elektronen, D-52425 Jülich, Germany Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
Andreas Gerber
Affiliation:
Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
Martin P. Weides
Affiliation:
Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
Knut Urban
Affiliation:
Ernst Ruska-Centrum für Mikroskopie und Spektroskopie mit Elektronen, D-52425 Jülich, Germany Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
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Abstract

The structural properties of β-phase tantalum nanocrystallites prepared by room temperature magnetron sputter deposition on amorphous carbon substrates are investigated at atomic resolution. For these purposes spherical aberration-corrected high-resolution transmission electron microscopy is applied in tandem with the numerical retrieval of the exit-plane wavefunction as obtained from a through-focus series of experimental micrographs. We demonstrate that recent improvements in the resolving power of electron microscopes enable the imaging of the atomic structure of β-tantalum with column spacings of solely 0.127 nm with directly interpretable contrast features. For the first time ever, we substantiate the existence of grain boundaries of 30° tilt type in β-Ta whose formation may be well explained by atomic agglomeration processes taking place during sputter deposition.

Type
Materials Applications
Copyright
© 2005 Microscopy Society of America

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References

REFERENCES

Abelmann, L. & Lodder, C. (1997). Oblique evaporation and surface diffusion. Thin Solid Films 305, 121.Google Scholar
Arakcheeva, A., Chapuis, G., & Grinevitch, V. (2002). The self-hosting structure of β-Ta. Acta Cryst B 58, 17.Google Scholar
Boothroyd, C.B. (1998). Why don't high resolution simulations and images match? J Microsc 190, 99108.Google Scholar
Coene, W.M.J., Thust, A., Op De Beeck, M., & Van Dyck, D. (1996). Maximum-likelihood methods for focus-variation image reconstruction in high resolution transmission electron microscopy. Ultramicroscopy 64, 109135.Google Scholar
Face, D.W. & Prober, D.E. (1987). Nucleation of body-centred-cubic tantalum films with a thin niobium underlayer. J Vac Sci Technol A 5, 34083411.Google Scholar
Feinstein, L.G. & Huttemann, R.D. (1973). Factors controlling the structure of sputtered Ta films. Thin Solid Films 16, 129145.Google Scholar
Gatan Inc. (1999). DigitalMicrograph 3.4 User's Guide. Pleasanton, CA: Gatan Inc.
Gupta, D. (1995). Diffusion in several materials relevant to Cu interconnection technology. Mater Chem Phys 41, 199205.Google Scholar
Haider, M., Rose, H., Uhlemann, S., Schwan, E., Kabius, B., & Urban, K. (1998). Electron microscopy image enhanced. Nature 392, 768769.Google Scholar
Hieber, K. & Mayer, N.M. (1982). Structural changes of evaporated tantalum during film growth. Thin Solid Films 90, 4350.Google Scholar
Hirsch, P., Howie, A., Nicholson, R., Pashley, D.W., & Whelan, M.J. (1965). Electron Microscopy of Thin Crystals. London: Butterworth.
Hübner, R., Hecker, M., Mattern, N., Hoffmann, V., Wetzig, K., Wenger, C., Engelmann, H.J., Wenzel, C., Zschech, E., & Bartha, J.W. (2003). Structure and thermal stability of graded Ta-TaN diffusion barriers between Cu and SiO_{2}. Thin Solid Films 437, 248256.Google Scholar
Hÿtch, M.J. & Stobbs, W.M. (1994). Quantitative comparison of high resolution TEM images with image simulations. Ultramicroscopy 53, 191203.Google Scholar
Jia, C.L., Lentzen, M., & Urban, K. (2004). High-resolution transmission electron microscopy using negative spherical aberration. Microsc Microanal 10, 174184.Google Scholar
Jiang, A., Yohannan, A., Nnolim, N.O., Tyson, T.A., Axe, L., Lee, S.L., & Cote, P. (2003). Investigation of the structure of β-tantalum. Thin Solid Films 437, 116122.Google Scholar
Klaver, P. & Thijsse, B. (2002). Thin Ta films: Growth, stability, and diffusion studied by molecular-dynamics simulations. Thin Solid Films 413, 110120.Google Scholar
Kwon, K.W., Lee, H.J., & Sinclair, R. (1999). Solid-state amorphization at tetragonal-Ta/Cu interfaces. Appl Phys Lett 75, 935937.Google Scholar
Laurila, T., Zeng, K., Kivilahti, K., Molarius, J., & Suni, I. (2000). Failure mechanism of Ta diffusion barrier between Cu and Si. J Appl Phys 88, 33773384.Google Scholar
Lentzen, M., Jahnen, B., Jia, C.L., Tillmann, K., & Urban, K. (2002). High-resolution imaging with an aberration-corrected transmission electron microscope. Ultramicroscopy 92, 233242.Google Scholar
Moseley, P.T. & Seabrook, C.J. (1973). The crystal structure of β-tantalum. Acta Cryst B 29, 11701171.Google Scholar
O'Keefe, M.A. & Kilaas, R. (1988). Advances in high-resolution image simulation. Scan Microsc Suppl 2, 225244.Google Scholar
Read, M.H. & Altman, C. (1965). A new structure in tantalum thin films. Appl Phys Lett 7, 5152.Google Scholar
Sajovec, F., Meuffels, P.M., & Schober, T. (1992). Structural and electrical properties of ion beam sputter deposited tantalum films. Thin Solid Films 219, 206209.Google Scholar
Stadelmann, P.A. (1987). EMS—A software package for electron diffraction analysis and HREM image simulation in materials science. Ultramicroscopy 21, 131145.Google Scholar
Stokes, R.J. & Evans, D.F. (1997). Fundamentals of Interfacial Engineering. New York: John Wiley & Sons.
Thust, A., Coene, W.M.J., Op De Beeck, M., & Van Dyck, D. (1996a). Focal-series reconstruction in HRTEM: Simulation studies on non-periodic objects. Ultramicroscopy 64, 211230.Google Scholar
Thust, A., Jia, C.L., & Urban, K. (2002). Extraction of imaging parameters from the object wave function in phase-retrieval electron microscopy. In Proceedings of the 15th International Congress on Electron Microscopy, Cross, R. (Ed.), vol. 3, pp. 167168. Durban, South Africa: Microscopy Society of Southern Africa.
Thust, A., Overwijk, M.H.F., Coene, W.M.J., & Lentzen, M. (1996b). Numerical correction of lens aberrations in phase-retrieval HRTEM. Ultramicroscopy 64, 249264.Google Scholar
Tillmann, K., Thust, A., & Urban, K. (2004). Spherical aberration correction in tandem with exit-plane wave reconstruction: Interlocking tools for the atomic scale imaging of lattice defects in GaAs. Microsc Microanal 10, 185198.Google Scholar
Venables, J.A., Spiller, G.D.T., & Hanbücken, M. (1984). Nucleation and growth of thin films. Rep Prog Phys 47, 399459.Google Scholar
Westwood, W.D. (1973). X-ray analysis of tantalum films triode-sputtered in argon–oxygen mixtures. Thin Solid Films 15, 1530.Google Scholar
Westwood, W.D., Waterhouse, N., & Wilcox, P.S. (1975). Tantalum Thin Films. London: Academic Press.