摘要
利用自制的冷壁石英腔 UHV/CVD设备 ,60 0℃条件下 ,通过 Ge组分渐变缓冲层技术 ,在 Si( 1 0 0 )衬底上成功地生长出完全弛豫、无穿透位错的 Si0 .83Ge0 .17外延层 ,并在其上获得了具有张应变的 Si盖帽层 .另外 ,还在 550℃下生长了同样结构的样品 ,发现此样品厚度明显变薄 ,组分渐变层的应变释放不完全 ,位错网稀疏而且不均匀 ,其上的 Si0 .83Ge0 .
The fully relaxed Si\-\{0.83\}Ge\-\{0.17\} epitaxial layer with Ge composition grade buffer layer is grown at 600℃ by our cold\|wall ultrahigh vacuum chemical vapor deposition system (UHV/CVD). The transmission electron microscopy (TEM) image shows that the Si 0.83 Ge 0.17 epitaxial layer is free of dislocations, and the Si cap layer on it is in tensile strain. Additionally, it is found that the temperature can affect the results of the growth greatly. The higher temperature can increase the growth rate and accelerate the relaxation velocity of the Ge composition grade layers. This is of advantage to the growth of thick Ge composition grade layers.
