溅射气压对Ge/Si纳米点表面形貌的影响

Effect of sputtering pressure on the surface morphology of the Ge/Si nanodots

利用磁控溅射技术在Si(100)衬底上直接外延生长一系列不同压强下的Ge纳米点样品,并利用AFM、Raman和XRF对Ge纳米点样品形貌和结构进行了研究。结果表明Ge薄膜表面粗糙度在某一临界压强下发生突变,高能粒子热化的临界值与这种转变密切相联;分析讨论了Ge岛在不同溅射气压下的生长过程,在一定范围随着压强的增大会显示典型生长阶段的特征。

A series of Ge nanodots samples on Si （100） surface were epitaxial grown with different pressures by using magnetron sputtering technique. The morphology and structure of Ge nanodots were also characterized by atomic force microscopy （AFM）,Raman and X-ray fluorescence spectrum （XRF）. It is indicated that the surface roughness of the films have an abrupt transition at a critical pressure. Such transition shows a close relation with the turning point of energetic particle thermalization. The growth process of nano-island is well analyzed, and the typical growth stage of nano-island and film with the increase of pressure in certain ranges is also presented.