A Search for Subsurface Dopants on Hydrogen-Terminated Si(111) Surfaces
A Search for Subsurface Dopants on Hydrogen-Terminated Si(111) Surfaces
复制标题
氢封端 Si(111) 表面次表面掺杂剂的研究
DOI：
10.1143/jjap.42.4655
复制
发表时间：
2003
影响因子：
1.5
通讯作者：
A. Sakai
中科院分区：
文献类型：
--
作者：
S. Kurokawa;T. Takei;A. Sakai
用扫描隧道显微镜(STM)和势垒高度成像(BH)观察到了位于氢端Si(111)1×1表面下的掺杂原子。由于氢终止的Si(111)1×1表面在带隙内没有明显的表面态，因此与清洁的硅表面相比，该表面对亚表面掺杂的屏蔽作用可能较弱。这使得我们能够通过STM观察到靠近表面的带电掺杂。同时获得的BH图像显示，掺杂位置上方的表面电势局部降低。隧道势垒高度的平均降低为∼-1.5 eV。
Dopant atoms located beneath the hydrogen terminated Si(111)1×1 surface have been observed by scanning tunneling microscopy (STM) and barrier-height (BH) imaging. Since the hydrogen terminated Si(111)1×1 surface has no significant surface states within the band gap, the screening effect of this surface on subsurface dopants is expected to be weak, compared to that on clean silicon surfaces. This enables us to observe electrically charged dopants located near the surface by STM. Simultaneously obtained BH images show a local reduction of surface potential above the dopant sites. The average reduction of the tunneling barrier height is ∼-1.5 eV.