NEW TECHNIQUE FOR SURFACE CRYSTALLOGRAPHY: DIRECT INVERSION OF KIKUCHI ELECTRON PATTERNS. C. M. Wei, Institute of Physics, Academia Sinica, NanKang, Taipei, Taiwan 11529, Republic of China

Direct inversion of the diffraction patterns of low-energy Kikuchi electrons named Kikuchi electron holography, using integral-energy phase-summing method [1], is found to yield the three-dimensional Patterson function of the near-surface structure. The results on the Ag(100), Ag(111), Si(001) (2x1), and Si(111) [[radical]]3x[[radical]]3 R30deg.-Au surfaces will be present. High-fidelity, artifact-free three-dimensional images of nearby atoms measured from the emitters on surfaces are obtained with a high-resolution (~1Å) in all direction [2]. These works have demonstrated high surface sensitivity of Kikuchi electrons and thus led to direct surface structural determination by inverting Kikuchi electron patterns. Finally, the future of this new surface technique will be discussed.

[1] C. M. Wei and S. Y. Tong, Surf. Sci. Lett. 274, L577 (1992).

[2] C. M. Wei, I. H. Hong, and Y. C. Chou, Surface Review Letters 1, p335 (1994)