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Direct UHV-TEM Observation of Palladium Clusters on a Silicon Surface

Published online by Cambridge University Press:  22 January 2004

Masaki Takeguchi ,
Kazutaka Mitsuishi ,
Miyoko Tanaka  and
Kazuo Furuya
Masaki Takeguchi
Affiliation:
Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan
Kazutaka Mitsuishi
Affiliation:
Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan
Miyoko Tanaka
Affiliation:
Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan
Kazuo Furuya
Affiliation:
Nanomaterials Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan
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Abstract

About 1 monolayer of palladium was deposited onto a silicon (111) 7 × 7 surface at a temperature of about 550 K inside an ultrahigh vacuum transmission electron microscope, resulting in formation of Pd2Si nanoislands and a 1 × 1 surface layer. Pd clusters created from an excess of Pd atoms on the 1 × 1 surface layer were directly observed by in situ plan view high-resolution transmission electron microscopy. When an objective aperture was introduced so that electron diffractions less than 0.20 nm were filtered out, the lattice structure of the 1 × 1 surface with 0.33 nm spacing and the Pd clusters with a trimer shape were visualized. It was found that image contrast of the 1 × 1 lattice on the specific height terraces disappeared, and thereby an atomic structure of the Pd clusters was clearly observed. The appearance and disappearance of the 1 × 1 lattice was explained by the effect of the kinematical diffraction. It was identified that a Pd cluster was composed of three Pd atoms without a centered Si atom, which is consistent with the model proposed previously. The feature of the Pd clusters stuck at the surface step was also described.

Keywords

UHV-TEMHRTEMsurface structurepalladiumcluster
Type
Research Article
Information
Microscopy and Microanalysis , Volume 10 , Issue 1 , February 2004 , pp. 134 - 138
Copyright
© 2004 Microscopy Society of America

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References

REFERENCES

Chen, Y., Ohlberg, D.A.A., & Williams, R.S. (2002). Nanowires of four epitaxial hexagonal silicides grown on Si(001). J Appl Phys 91, 3213–3218.Google Scholar
Cherns, D. (1974). Direct resolution of surface atomic steps by transmission electron-microscopy. Phil Mag 30, 549–556.Google Scholar
Edington, J.W. (1976). Practical Electron Microscopy in Materials Science. Appendix 8. New York: Van Nostrand Reinhold Co.
Ichihashi, T. (1996). In situ observation of oxidation and etching of silicon by ultra-high-vacuum transmission electron microscopy. Jpn J Appl Phys 35, 6610–6613.Google Scholar
Ozawa, S., Yamazaki, A., Kobayashi, K., Tanishiro, Y., & Yagi, K. (1990). A new technique to produce clean and thin silicon films in situ in a UHV electron microscope for TEM-TED studies of surfaces. Jpn J Appl Phys 29, L655–L658.Google Scholar
Suematsu, T., Tanaka, M., Fujii, T., Hashimoto, S., Kumagai, Y., & Hasegawa, F. (1997). Aggregation of monocrystalline β-FeSi2 by annealing and by Si overlayer growth. Jpn J Appl Phys 36, L1225–L1228.Google Scholar
Takeda, S., Koto, K., Iijima, S., & Ichihashi, T. (1997). Nanoholes on silicon surface created by electron irradiation under ultrahigh vacuum environment. Phys Rev Lett 79, 2994–2997.Google Scholar
Takeguchi, M., Mitsuishi, K., Tanaka, M., & Furuya, K. (2003). UHV-HRTEM observation of Pd clusters on Pd adsorbed Si (111) 1 × 1 surface. Surf Sci 532–535, 671–677.Google Scholar
Takeguchi, M., Tanaka, M., Yasuda, H., & Furuya, K. (2001a). Cross-sectional high-resolution transmission electron microscopy observation of Si(113) 3 × 2 structure. Surf Sci 482–485, 1385–1391.Google Scholar
Takeguchi, M., Tanaka, M., Yasuda, H., & Furuya, K. (2001b). Real-time high-resolution transmission electron microscopy observation of the growth process of (001) surfaces on a nanometer-sized Si multiply twinned particle. Surf Sci 493, 414–419.Google Scholar
Takeguchi, M., Tanaka, M., Yasuda, H., & Furuya, K. (2001c). Analytical ultrahigh-vacuum transmission electron microscopy applied to the studies of Pd2Si island formation on Si(111) surfaces. Surf Interface Anal 31, 68–72.Google Scholar
Tanaka, N., Kimata, H., & Kizuka, T. (1997). Time-resolved high-resolution electron microscopy of step-diffusion of tungsten atoms on MgO(001) surface. Surf Sci 386, 216–221.Google Scholar