We investigated the structural property of MgO thin films on Si(001) substrates by molecular beam epitaxy in order to obtain (001)-oriented MgO barrier for high spin polarization on Si substrate. The MgO layer deposited at 200℃ and deposition rate of 0.30 nm/min grew with (001)-orientation on Si(001) substrate. The (001)-orientation and crystallization of the MgO layer were enhanced by insertion of Mg layer into interface between Si substrate and MgO layer. It is considered that the Mg layer prevented oxidation of Si at interface and functioned as buffer layer.
