Field Emission Studies of Surface Diffusion of Adsorbates
The field emission microscope, invented by E. W. Müller in 1937, has proved to be remarkably useful for studying the diffusion of adsorbed atoms or molecules on metal surfaces. Two quite distinct but complementary ways of using it for this purpose exist, namely shadowing and the measurement of current fluctuations. The former provides information on overall diffusion behavior in a very graphic way; the latter focuses more narrowly on diffusion under very well-defined conditions on a single crystal plane. This article will give a very brief review of the salient features of the field emission microscope, describe the shadowing and fluctuation methods, and will present some results obtained with them. These, more than any discussion, will give the reader a feeling for the strengths and weaknesses of the two methods.
KeywordsWork Function Surface Diffusion Boundary Diffusion Trap Site Sticking Coefficient
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- 1.R. Gourer, in: “Structure and Properties of Metal Surfaces,” p. 128, Honda Memorial Series on Material Science, Maruzen Lt., Tokyo ( 1973 ); R. Gourer, “Field Emission and Field Ionization,” Harvard University Press, Cambridge, Mass. (1960).Google Scholar
- 7.R. Gourer, J. Chem. Phys. 28: 168 (1958).Google Scholar
- 10.R. Lewis and R. Gourer, Nuovo Cimento, V: 506 (1967).Google Scholar
- 21.R. Wortman, R. Gourer, and R. Lundy, J. Chem. Phys. 27: 1099 (1957).Google Scholar
- 26.M. G. Lagally, T.-M. Lu, and G.-C. Wang, in: “Ordering in Two Dimensions,” S. K. Sunha, ed., Elsevier-North Holland Press, New York (1980), p. 113.Google Scholar
- 27.M. Tringides, to be published.Google Scholar
- 28.R. DiFoggio and R. Gourer, Phys. Rev. B, to be published.Google Scholar