Single-crystal silicon nanowires

Cui, Y. Lauhon, L. I Gudiksen, M. S. Wang, J. Lieber, C. M. 2001. Diameter-controlled synthesis of single-crystal silicon nanowires. Appl. Phys. Lett. 78 2214-2216. 

Lu, X. Hanrath, T. Johnston, K.P. Korgel, B.A. Growth of single-crystal silicon nanowires in supercritical solution from tethered gold particles on a silicon substrate. Nano Lett. 2003, 3 (1), 93-99. 

A first-principles study of morphology and stability of single crystal silicon nanowires with <001>, <011>, <111> and <112> axes and diameters of 2-5 nm is presented. Different shapes and facet reconstructions have been carefully considered to select the morphology more stable in energy. We find that the <011>-oriented silicon nanowires display the lowest total energy and we also discuss how our results support recent experimental observations. 

Laser ablation Liquid metal alloy nanodroplets 0 Single crystal silicon nanowires 0 Single crystal Ge nanowires... 

Sheath core Si02 / Si nanowire with Fe tip solid) Single crystal silicon nanowire solid phase)... 

A more recent approach, also from the Suizdak group, is to modify silicon surfaces with single-crystal silicon nanowires (SiNWs), which also happen to provide a good platform for surface-based mass spectrometry. Those silicon nanowires are directly synthesized on the surface of a silicon wafer. The formation of SiNW can be well controlled to define physical dimensions, composition, density, and position of the nanowires on the surface [193,194]. 

Tong, H.D., et al, 2009. Novel top-down wafer-scale fabrication of single crystal silicon nanowires. Nano Lett. 9 (3), 1015-1022. 

While the discussion in this chapter has focused on molecular layers on single crystal silicon surfaces, the attachment chemistries discussed here could easily be applied to functionalize silicon nanowires or nanoparticles. Silicon nanowires have been shown to exhibit interesting electrical transport characteristics and have been used to fabricate nanoscale pn junctions [95], field effect transistors [96] and biochemical sensors [97-100]. However, all these interesting phenomena have been reported on oxidized silicon nanowires. It is likely that better control over the surface properties, as could be achieved by employing some of the chemistry discussed here, could significantly improve the performance of these nanowire-based devices. From another perspective, silicon nanowires could prove extremely... 

Prof. Hong Li and co-works from the Institute of Physics, Chinese Academy of science, also purposed to use nanosized silicon as anode for LIBs, which is the first patent of nano-Si anode in the world.They have found that nanosized Si particle showed much better cyclic performance than micrometer sized silicon at room temperature. " Later, they found the room-temperature amorphization phenomenon for single crystal Si nanowires after lithiation and electrochemical agglomeration of nanosized Si particles. " ... 

FETs are actually the basic building blocks of integrated circuits. To develop circuits using nanotubes, we first have to design nanotube-based transistors. Silicon nanowires represent one of the best characterized examples of semiconductor nanotubes with the structure, size, and electronic properties controlled reproducibly (Hu et al., 1999 Cui et al., 2001a). In particular, silicon nanowires can be prepared as single-crystal structures with controllable diameters as small as 2 to 3 nm (Cui et al., 2003 Wu, 2004). Both n- and p-type FET devices can be produced with well-defined and reproducible high-performance properties... 

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