Hydrogen-terminated silicon surface

The radical-based functionalization of silicon surfaces is a growing area because of the potential practical applications. Although further knowledge is needed, the scope, limitations, and mechanism of these reachons are sufficiently well understood that they can be used predictably and reliably in the modification of hydrogen-terminated silicon surfaces. The radical chemistry of (TMSlsSiH has frequently served as a model in reactions of both hydrogen-terminated porous and flat silicon surfaces. We trust that the survey presented here will serve as a platform to expand silicon radical chemistry with new and exciting discoveries. 

In 1993, Linford firstly reported a quite useful method to prepare monolayers of alkyl chains by thermal hydros-ilylation of hydrogen-terminated silicon surfaces [25]. Alkyl chains are covalently bound to Si surface by Si-C bonds. This thermal hydrosilylation could be attributed to a free-radical process with 1-alkene. First, a diacyl peroxide initiator was used to produce free radicals. However, at higher temperature, only hydrogen-terminated silicon and a neat solution of 1-alkene or 1-alkyne can form Si-C linkages [26]. Furthermore, lately it is found that such Si-C covalent links can be observed even in dilute solutions of 1-alkenes [27]. In that case, the density of monolayer packing strongly depends on the reaction temperature. 

Immobilization of Gold Nanoparticles onto Hydrogen-Terminated Silicon Surface by Si-C Covalent Bonds... 

Wet preparation of metal nanoparticles and their covalent immobilization onto silicon surface has been surveyed in this manuscript. Thiol-metal interaction can be widely used in order to functionalize the surface of metal nanoparticles by SAM formation. Various thiol molecules have been used for this purpose. The obtained functionalized particles can be purified to avoid the effect of unbounded molecules. On the other hand, hydrogen-terminated silicon surface is a good substrate to be covered by Si-C covalently bonded monolayer and can be functionalized readily by this link formation. Nanomaterials, such as biomolecules or nanoparticles, can be immobilized onto silicon surface by applying this monolayer formation system. 

Robertson has summarized the three recent classes of models of a-Si H deposition [439]. In the first one, proposed by Ganguly and Matsuda [399, 440], the adsorbed SiHa radical reacts with the hydrogen-terminated silicon surface by abstraction or addition, which creates and removes dangling bonds. They further argue that these reactions determine the bulk dangling bond density, as the surface dangling bonds are buried by deposition of subsequent layers to become bulk defects. 

Wayner, D. D. M. and Wolkow, R. A. Organic modification of hydrogen terminated silicon surfaces. Journal of the Chemical Society-Perkin Transactions 2, 23 (2002). 

Some examples of molecular adsorbates on the patterned hydrogen terminated silicon surface are shown in Fig. 13. Perhaps the most notable for... 

The procedure for preparing atomically smooth, hydrogen-terminated silicon surfaces involves a number of steps removal of hydrocarbon contamination, formation of a uniform oxide, oxide removal, etching of the silicon surface, and the formation of the passivation layer. The uniformity of the oxide is important in developing a smooth surface at the Si/Si02 interface. 

Scanning probe lithography on metal or silicon substrates is a well known technique and can be supported by a self-assembled monolayer (SAM) [1,2], Such monolayers are of great interest e.g. for passivation of silicon surfaces [3]. Covalently bound monolayers by Si-C bonds that are formed by the reaction of 1-alkenes and a hydrogen terminated silicon surface [4,5], are known to show high thermal [6] as well as chemical stability [3,7]. 

Lie L. H., Patole, S. N., Hart E. R., Houlton A. and Horrocks B. R. (2002), Photochemical reaction of diazomethane with hydrogen-terminated silicon surfaces , J. Phys. Chem. B 106, 113-120. 

Kaiser WJ, BeU LD, Hecht MH, Gnmthaner FJ (1988) Scanning mnneling tmcroscopy characterization of the geometric and electronic stmcture of hydrogen terminated silicon surfaces. J Vac Sci Tech A Vac Surf Films 6 519-523... 

Although silicon nanocrystals are now more commonly prepared by a variety of means which are easier to scale up, e.g., pyrolysis of silanes (Xuegeng et al. 2004), thermal treatment of silsesquioxanes (Hessel et al. 2006, 2010), and from reactions of molecular silicon compounds (Wilcoxon et al. 1999 Bley and Kauzlarich 1996), this review will concentrate on routes which proceed via the formation of porous silicon. More general reviews of silicon nanocrystals Irom physics and chemistry perspectives are available (Shirahata 2011 Kang et al. 2011 Heitmann et al. 2005). Derivatization of porous silicon and SiNCs usually relies on the chemistry of the hydrogen-terminated silicon surface, which shares some of the organic reactivity of hydrosilanes (Buriak 2002). Reaction with alcohols results in Si-O-C bonded monolayers (Sweryda-Krawiec et al. 1999), but these are suseeptible to hydrolysis under ambient conditions. Alternately, addition of surface Si-H aeross a C = C double bond produces Si-C bonded monolayers, which are very stable. 

Fabre, B. Ferrocene-terminated monolayers covalently bound to hydrogen-terminated silicon surfaces. Toward the development of charge storage and communication devices. Acc. Chem. Res. 43, 2010 1509-1518. 

T. Takahagi, 2001, Atomic-scale defect control on hydrogen-terminated silicon surface at wafer scale , Appl. Phys. Lett. 78, 309-311. 

Yzambart G, Fabre B, Camerel F, Roisnel T, Lorcy D (2012) Controlled grafting of tetrathiafulvalene (TTF) containing diacetylenic units on hydrogen-terminated silicon surfaces from redox-active TTF monolayer to polymer films. J Phys Chem C 116 12093-12102... 

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