Oxidation reactions at an unpaired dangling-bond site on a H-terminated (100)-(2 x 1) surface were studied by using an ultra-high vacuum scanning tunnelling microscope. The surface image was observed in situ during exposure to O molecules at room temperature. During exposure, the unpaired dangling-bonds produced structural changes around themselves, and they were localized mainly on one side of a Si dimer bond. It was concluded that back-bonds near to an unpaired dangling bond were preferentially oxidized, following the dissociation of O molecules at the unpaired dangling-bond site.

Initial backbond oxidation at an unpaired dangling bond site on a hydrogen-terminated Si(100)-(2 x 1) surface H.Kajiyama, S.Heike, T.Hitosugi, T.Hashizume: Japanese Journal of Applied Physics - 2, 1998, 37[11B], L1350-3