title: Epitaxial growth of vertically free-standing ultra-thin silicon nanowires.
abstract: We report epitaxial growth of ultra-thin vertically free-standing silicon nanowires (Si NWs) on Si(111) and Si(110) substrate, by an ultra-high vacuum chemical vapor deposition method. The epitaxial growth direction of Si NWs with sub-10 nm diameters was found to be dependent upon the orientation type of the Si substrate. The 〈112〉 and 〈110〉 epitaxial growth directions are crystallographically preferred on Si(111) and Si(110) substrates, respectively. Especially, for the epitaxy on Si(110), most of the Si NWs are grown vertically in the [110] direction with sub-5 nm diameters. Based on transmission electron microscope investigations, a growth model for ultra-thin Si NWs was deduced from the morphology of interface between catalyst and nanowire, and the growth direction at a very early stage of epitaxy was determined.
authors: Institute for Advanced Materials and Laboratory of Quantum Engineering and Quantum Materials, South China Academy of Advanced Optoelectronics, Guangzhou 510006, People's Republic of China.
authors: Qingwei
authors: Q
authors: Zhou
authors: Liwei
authors: L
authors: Liu
authors: Xingsen
authors: X
authors: Gao
authors: Lijun
authors: L
authors: Chen
authors: Stephan
authors: S
authors: Senz
authors: Zhang
authors: Z
authors: Zhang
authors: Junming
authors: J
authors: Liu