Si3N4/Si表面Si生长过程的扫描隧道显微镜研究

利用原位扫描隧道显微镜和低能电子衍射分析了Si的纳米颗粒在Si₃N₄/Si(111)和Si₃N₄/Si(100)表面生长过程的结构演变.在生长早期T为350—1075K范围内,Si在两种衬底表面上都形成高密度的三维纳米团簇,这些团簇的大小均在几个纳米范围内,并且在高温退火时保持相当稳定的形状而不相互融合.当生长继续时,Si的晶体小面开始显现.在晶态的Si₃N₄(0001)/S 关键词： 氮化硅 扫描隧道显微镜 纳米颗粒

SCANNING TUNNELING MICROSCOPY STUDY OF Si GROWTH ON Si3N4/Si SURFACE

The growth of Si on silicon nitride surfaces has been studied using in situ STM, low energy electron diffraction and Auger electron spectroscopy. In the early stage(T=350—1075 K), Si nano-clusters can appear on different substrates. These clusters are round with sizes in the range of several nanometers.They are also rather stable when the substrate temperature changes (or annealing). As these clusters grow continually, crystalline facets start to form. On the crystalline Si₃N₄(0001)/Si(111), Si islands with (111) oriented top facets grow faster than others, and they are aligned with the original Si(111) substrate. Finally, Si(111) became the dominant feature on the whole surface. In contrast, on the amorphous Si₃N₄ surface, Si islands grow in random orientation. Low-index facets, such as (111) and (100), and high-index facets, such as (113), coexist. Some discussions are given to explain the above growth procedures.