摘要
Using the first-principle self-consistent linear-muffin-tin-orbital method within the local density approximation,band structure of(111)-oriented strained-layer SiGe superlattice is studied.Three different ordered arrangements of atom layers(Si-Ge■Si-Ge Si-Si■Ge-Ge and Si■Si-Ge■Ge)are considered.Calculated results indicate that(111)-oriented SiGe strained layer superlattices are semiconductive,with a band gap about 1.OeV.The first two superlattices are indirect band gap semiconductors,and the third one(Si■Si-Ge■Ge)is a direct band gap semiconductor.The influence of strain on the band structure is also investigated.
