P-Silicon

Manufacture of P-Silicon Carbide. A commercially utilized appHcation of polysdanes is the conversion of some homopolymers and copolymers to siHcon carbide (130). For example, polydimethyl silane is converted to the ceramic in a series of thermal processing steps. SiHcon carbide fibers is commercialized by the Nippon Carbon Co. under the trade name Nicalon (see Refractory fibers). 

Fig. 7.9. Measurements of the degree of conversion of ct p silicon nitride at a fixed time and various temperatures are thought to show the strong influence of shock modification on the high temperature dissolution [84B01].

Lopour P, Plichta Z, Volfova Z, Hron P, and Vondracek P. Silicone rubber-hydrogel composites as polymeric biomaterials. Biomaterials, 1993, 14(14), 1051-1055. 

Lednicky F, Janatova V, and Lopour P. Silicone rubber-hydrogel composite as polymeric biomaterials [J]. Biomaterials, 1991, 12, 848. 

A (100) oriented p-silicon wafer (Wacker Chemitronic) was cut into 5x5 mm pieces. These were cleaned in a UV/ozone dry stripper (Samco) for 15 min followed by a two minute rinse in doubly deionized water. The samples were dried in clean air for several minutes. A 10 pi amount of TEOS (purchased by Aldrich, electronic grade, as received) was dropped onto the dried surfaces. The film was allowed to dry in ambient air for 10 minutes and then immediately transferred into the vaccum-chamber of the TOF-SIMS spectrometer. 

A. Y. Liu and M. L. Cohen, Structural Properties and Electronic Structure of Low-Compressibility Materials P-silicon Nitride and Hypothetical Carbon Nitride (P-C3N4), Phys. Rev. B, 41(15), 10727-34 (1990). 

Figure 11.12. Si electrode and NW hybrid device, (a) Schematic of a single LED fabricated by the method outlined in Fig. 11.11. (b) I-V behavior for a crossed p-n junction formed between a fabricated p+-Si electrode and an n-CdS NW. (c) EL spectrum from the forward biased junction, (d) SEM image of a CdS NW assembled over seven p+-silicon electrodes on a SOI wafer (e) EL image recorded from an array consisting of a CdS NW crossing seven p+-Si electrodes. The image was acquired with +5V applied to each silicon electrode while the CdS NW was grounded. [Reprinted with permission from Ref. 59. Copyright 2005 Wiley-VCH Verlag.]...

Reed, G. T. Knights, A. P., Silicon Photonics An Introduction, Wiley, Chichester 2004... 

Colvin, E. U. Silicon in Organic Synthesis " Butterworths London, 1981 Weber, W. P. "Silicon Reagents for Organic Synthesis " Springer-Verlag Berlin, 1983. 

Maier CU, Specht M, Bilger G (1996) Hydrogen evolution on platinum-coated p-silicon photocathodes. Int J Hydrogen Energy 21 859-864... 

The ceramic, polycrystalline silicon carbide [409-21 -2], SiC, is processed using p-silicon carbide and boron (9). The boron is a sintering aid used at... 

Gu, H. and Shinoda, Y., (2000), Structural and chemical widths of general grain boundaries modification of local structure and bonding by boron-doping in P-silicon carbide , Interface Science, 8 (2/3), 269-278. 

Tentative evidence that the insertion of dichlorocarbene occurs preferentially into the C-H bond which is anti-periplanar to a p-silicon or tin is suggested from an examination of the stereochemistry of its reaction with scc-butyltrimethylsilane 67 M = Si and veobutyltrimethylstannane 67 M = Sn (Scheme 6).66 Both substrates gave an uneven mixture of the erythro-68 and threo-69 diastereoisomers, but the diastereomeric product ratio derived from the silicon compound was opposite to that obtained from the tin compound. The diastereoselectivity was rationalized as reflecting the preferential insertion of dichlorocarbene into the anti-periplanar C-H bond (with retention of configuration) in the most stable conformation. By the predictions of molecular... 

Fig. 15.9. Depth profiles of the Pt Af and 2s photoelectron signal of the electron beam-evaporated Pt layer on Si and the concentration profiles of Pt, Si, O and C. (Reprinted from C. U. Maier, Hydrogen Evolution on Platinum-Coated p-Silicon Photocathodes, Int. J. Hydrogen Energy21 840,1996. Reproduced with permission of the International Association for Hydrogen Energy.)...

Weber, W. P. Silicon Reagents for Organic. Synthesis Springer Berlin. 1983. 

Habereder P, Silicon-Weichmacher Struktur-Wirkungsbeziehungen , Melliand... 

Over the past few years, the debate over the origin of the p-silicon effect on carbocations has narrowed to one of the relative magnitudes of inductive and hyperconjugative factors. Theory and experiment are finally in agreement that hyperconjugation is by far the dominant factor—29 kcal/mol calculated to be from P-stabilization ( ) versus 9 kcal/mol from induction and polarization. The realization of these effects is dramatically revealed in the SnI solvolyses of the conformationally locked cyclohexyl trifluoroacetates (OTFA) (3-5), The relative solvolysis rates at 25 °C for compounds 3-5 are 1, 4 X 10, and 2.4 X 10, respectively. Compound 4 cannot attain the necessary anti-coplanar relationship of the Si-C and C-O bonds, which is present in 5 and required for full hyperconjugative interaction with the cation formed as the C-O bond suffers heterolysis. 

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