锗硅分子束外延层与衬底界面的电镜研究

Study of boundary between Ge_xSi_1-xMBE layer and Si substrate by TEM

使用分子束外延（ＭＢＥ）技术制备了应变锗硅外延薄膜，并在不同温度下对样品等时热退火处理；采用侧面透射电子显微镜（ＸＴＥＭ）对退火样品进行观测，获得有关高温退火后锗硅外延层与硅衬底界面的位错生长情况，采用高分辨电子显微镜（ＨＲＥＭ）观测样品退火以前的界面显微结构，表明样品在８５０℃退火温度时出现的位错生长是一种混合型热松弛机理．

The thermal relaxation of coherently strained GexSi1-x films grown by molecularbeam epitaxy on Si(100) is studied by cross-section transmission electron microscopy (XTEM) and high-resolution latticeimaging TEM. For anneals done at different temperatures up to 750℃, dislocation generation on the boundary proceeds slowly. However, at 850℃ thedislocation increases rapidly, which may be caused by dislocation climb aided by Ge interdiffusion.