Covalent attachment of acetylene and methylacetylene functionality to Si(111) surfaces: Scaffolds for organic surface functionalization while retaining Si-C passivation of Si(111) surface sites
Covalent attachment of acetylene and methylacetylene functionality to Si(111) surfaces: Scaffolds for organic surface functionalization while retaining Si-C passivation of Si(111) surface sites
复制标题
DOI：
10.1021/ja061969b
复制
发表时间：
2006-08-09
影响因子：
15
通讯作者：
Lewis, Nathan S.
中科院分区：
文献类型：
--
作者：
Hurley, Patrick T.;Nemanick, E. Joseph;Lewis, Nathan S.
Si（111）表面已经被Si-C <$C-R物种官能化，其中R = H或-CH 3，使用两步反应序列，包括H-Si（111）的氯化，然后用Na-C <$C-H或CH 3-C <$C-Na试剂处理。所得的表面没有显示出可检测到的氧化，如Si 2 p区域的X射线光电子能谱（XPS）数据、Si-H氧化的电化学测量或红外光谱所证明的。在2179 cm-1处，Si-C C-R终止的表面在红外线中表现出特征性的C C伸缩，其强烈极化垂直于Si（111）表面平面。在C 1 s区域的XPS测量显示出一个低的结合能峰，表明Si-C键合，在实验误差范围内，其覆盖率与CH 3封端的Si（111）表面的覆盖率相同，这已被证明可以完全终止未重构的Si（111）表面上的Si顶部位置。通过暴露于-C4 H9 Li，然后暴露于paraBr-C6 H5-CF 3，进一步官能化Si-C-C-H-封端的表面，允许引入para-C6 H5 CF 3基团，同时保持所需的化学和电学性质，伴随着Si（111）表面顶部位置的完全Si-C终止。
Si(111) surfaces have been functionalized with Si−C⋮C−R species, where R = H or −CH3, using a two-step reaction sequence involving chlorination of H−Si(111) followed by treatment with Na−C⋮C−H or CH3−C⋮C−Na reagents. The resulting surfaces showed no detectable oxidation as evidenced by X-ray photoelectron spectroscopic (XPS) data in the Si 2p region, electrochemical measurements of Si−H oxidation, or infrared spectroscopy. The Si−C⋮C−R-terminated surfaces exhibited a characteristic C⋮C stretch in the infrared at 2179 cm-1, which was strongly polarized perpendicular to the Si(111) surface plane. XPS measurements in the C 1s region showed a low binding energy peak indicative of Si−C bonding, with a coverage that was, within experimental error, identical to that of the CH3-terminated Si(111) surface, which has been shown to fully terminate the Si atop sites on an unreconstructed Si(111) surface. The Si−C⋮C−H-terminated surfaces were further functionalized by exposure ton-C4H9Li followed by exposure toparaBr−C6H5−CF3, allowing for introduction ofpara−C6H5CF3groups while maintaining the desirable chemical and electrical properties that accompany complete Si−C termination of the atop sites on the Si(111) surface.