Dimer structure of clean Si(001) surface studied by grazing-incidence back-scattering MEED

The buckled-dimer structure of the Si(001)2 × 1 surface has been studied as a performance test of an apparatus that was designed and constructed for grazing-incidence back-scattering medium energy electron diffraction (GBMEED). The apparatus mainly consists of a μ-electron-beam gun and an electron energy analyzer of retarding-field and two-dimensional-display type. A μ-electron-beam of 1 keV was incident at a grazing angle to a single-domain Si(001)2 × 1 surface and quasi-elastically back-scattered electron intensity patterns (GBMEED patterns) were displayed by the two-dimensional analyzer. It was shown that the buckled dimer structure of the Si(001)2 × 1 surface was directly reflected in the GBMEED patterns. This demonstrates the potential of the method and the capabilities of the GBMEED apparatus we have constructed as a promising surface-structure-analysis tool.