Core-level photoemission study of the Si(111)4x1-In surface

In 4d and Si 2p photoemission spectra for the Si(111)4x1-In surface have been measured. It is found that the In 4d spectra consist of mainly two components and that no significant surface core level shift is present on Si 2p. The latter finding suggests that the substrate is almost ideally terminated by a one-to-one bonding with In atoms. It is also found that the In 4d spectra are asymmetric in shape while Si 2p spectra are symmetric. This shows that In atoms form a metallic over-layer with covalent bondings to a semiconducting Si substrate. * Present address: Institute for Molecular Science, Okazaki 444, Japan.