理论和实验研究表明，在一定的应变和掺杂浓度下，Si基外延Ge薄膜能实现1.55μm光通信波段的直接带隙发光。讨论了Si基外延Ge材料的生长技术及其能带结构，结合本小组近年来在该领域所取得的成果，介绍了国内外各研究机构对Ge薄膜发光材料和器件的研究进展，展望了未来的发展趋势。

It has been theoretically and experimentally demonstrated that, with proper band structure engineering using inplain tensile stress and ntype doping, germanium can be used as efficient light emission materials and optical gain can be achieved at near 1550nm. In this paper, epitaxial growth of Ge on Si substrate and modulation of its band structure are summarized. The research progress on light emission of Sibased Ge epilayer is reviewed and the developing trends are discussed.