Si-SiO₂ interface structures on Si(100), (111), and (110) surfaces

The distributions of intermediate oxides (SiO_x, 0<x<2) in ultrathin oxide films formed on (100), (111), and (110) surfaces were investigated by using the nondestructive measurements of Si 2p photoelectron spectra. The experimental observations can be understood as follows: (1) the abrupt interfaces are formed for three crystal orientations; (2) the interface formed at 1000°C on (100), (111), and (110) surface consists mainly of SiO, Si₂O, and the mixture of SiO and Si₂O, respectively; (3) Si₂O₃ is distributed in the oxide films for three crystal orientations.