Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-24T02:29:38.997Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access

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

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

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