Photoreflectance Spectra of Highly-oriented Mg₂Si(111)//Si(111) Films

抄録

Direct transition energies of Mg₂Si were obtained by photoreflectance (PR) spectra of a highly-oriented Mg₂Si(111)//Si(111) film. In the PR spectra at 9 K, direct transition energies of E₁ = 2.38 eV, E₂ = 2.58 eV, E₃ = 2.69 eV, and E₄ = 2.82 eV were observed. In the temperature dependence of PR spectra, E₁ and E₂ shifted to lower energy at high temperatures, but there was no temperature dependence of transition energies in E₃ and E₄. These results showed that the temperature dependences of band structure in Mg₂Si differ at direct transition points.