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Effect of Electron Beam Irradiation on Si Surface Cleaning in Ultrahigh-Vacuum System

Effect of electron beam irradiation (15 kV) on Si surface cleaning prior to epitaxial growth in an ultrahigh-vacuum system was investigated. A CaF2 film was epitaxially grown on the Si surface, and the interface was observed by high-voltage electron microscopy. Amorphous layers, which were observed in the interface prepared with conventional thermal treatment at 750°C, became much smaller with electron beam irradiation after the thermal treatment. Based on the electron microscope observation, the effect of electron beam irradiation on Si surface cleaning was briefly discussed.