摘要
本文用透射电镜（ＸＴＥＭ）和二次离子质谱（ＳＩＭＳ）分析了由超高真空化学气相淀积法（ＵＨＶＣＶＤ）生长的ｎ－Ｓｉ／ｉ－ｐ＋－ｉＳｉＧｅ／ｎ－Ｓｉ结构，发现在硅上外延生长ｉ－ｐ＋－ｉＳｉＧｅ时，在靠近Ｓｉ的ｉ／ｐ＋ＳｉＧｅ界面处存在一个很薄的层，但在ｉ－ｐ＋－ｉＳｉＧｅ上外延生长Ｓｉ时，无此现象产生．此薄层是由在硅上外延生长ｉ－ｐ＋－ｉＳｉＧｅ时硼原子聚集在靠近Ｓｉ的ｉ／ｐ＋ＳｉＧｅ界面处形成的高掺杂薄层．高掺杂的薄层影响由此结构制备的异质结双极晶体管（ＨＢＴ）的ＢＣ结的正向导通电压．
Abstract n Si/i p + i SiGe/n Si structures grown by ultra high vacuum chemical vapor deposition are investigated by transmission electron microscopy and secondary ion mass spectrometry. It is found that a very thin layer exists at the interface of i/p + SiGe closer to the Si substrate when i p + i SiGe is grown on Si, and this phenomenon does not occur when Si is grown on i p + i SiGe. This thin layer is heavily boron doped due to the accumulation of boron atom at the interface of i/p + SiGe closer to the Si substrate. As a result, the turn on voltage of the BC junction of the SiGe HBT made from this structure was affected seriously
