Two-faced liquid silicon

Nature India ◽  
2011 ◽  
Keyword(s):  
Liquid Silicon

AEM of reaction-bonded SiC

1992 ◽  
Vol 50 (1) ◽  
pp. 344-345
Author(s):  
K Das Chowdhury ◽  
R. W. Carpenter ◽  
W. Braue
Keyword(s):  
Mechanical Properties ◽  
Phase Transformation ◽  
High Temperature ◽  
Epitaxial Growth ◽  
Liquid Silicon ◽  
Structural Ceramic ◽  
Few Data

Research on reaction-bonded SiC (RBSiC) is aimed at developing a reliable structural ceramic with improved mechanical properties. The starting materials for RBSiC were Si,C and α-SiC powder. The formation of the complex microstructure of RBSiC involves (i) solution of carbon in liquid silicon, (ii) nucleation and epitaxial growth of secondary β-SiC on the original α-SiC grains followed by (iii) β>α-SiC phase transformation of newly formed SiC. Due to their coherent nature, epitaxial SiC/SiC interfaces are considered to be segregation-free and “strong” with respect to their effect on the mechanical properties of RBSiC. But the “weak” Si/SiC interface limits its use in high temperature situations. However, few data exist on the structure and chemistry of these interfaces. Microanalytical results obtained by parallel EELS and HREM imaging are reported here.

The Interactions of Carbon and Nitrogen in Liquid Silicon

2014 ◽  
Vol 33 (4) ◽  
pp. 363-368 ◽  
Author(s):  
Halvor Dalaker ◽  
Merete Tangstad
Keyword(s):  
Silicon Nitride ◽  
Carbon Source ◽  
Nitrogen Content ◽  
High Purity ◽  
Liquid Silicon ◽  
Interaction Parameters ◽  
Carbon And Nitrogen ◽  
Temperature Range ◽  
High Purity Silicon

AbstractThe interactions between carbon and nitrogen in liquid silicon have been studied experimentally. High purity silicon was melted in silicon nitride crucibles under an Ar atmosphere with a graphite slab inserted in the crucible prior to melting as a carbon source. The system was thus simultaneously equilibrated with Si3N4 and SiC. Samples were extracted in the temperature range 1695–1798 K and analyzed using Leco.It was observed that the simultaneous saturation of nitrogen and carbon caused a significant increase in the solubilities of both elements. The interaction parameters were derived as The solubility of carbon in liquid silicon as a function of temperature and nitrogen content was found to follow: And the solubility of nitrogen in liquid silicon found to follow:

Liquid Silicon-Monona

2018 ◽  
Vol 53 (2) ◽  
pp. 214-228 ◽  
Author(s):  
Yue Zha ◽  
Jing Li
Keyword(s):  
Liquid Silicon

scholarly journals Persistence of Covalent Bonding in Liquid Silicon Probed by Inelastic X-Ray Scattering

2012 ◽  
Vol 108 (6) ◽  
Author(s):  
J. T. Okada ◽  
P. H.-L. Sit ◽  
Y. Watanabe ◽  
Y. J. Wang ◽  
B. Barbiellini ◽  
...  
Keyword(s):  
Covalent Bonding ◽  
Liquid Silicon ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Electrical Conductivity of SiC/Si Composites Obtained from Wood Preforms

2011 ◽  
Vol 66 (1-2) ◽  
pp. 134-138
Author(s):  
Marco Antonio Béjar ◽  
Rodrigo Mena ◽  
Juan Esteban Toro
Keyword(s):  
Electrical Conductivity ◽  
Silicon Content ◽  
Beech Wood ◽  
Liquid Silicon

Biomorphic SiC/Si composites were produced from pine and beech wood, and the corresponding electrical conductivity was determined as a function of the temperature. Firstly, wood preforms were pyrolized at 1050 °C in nitrogen. Then, the pyrolized preforms were impregnated with liquid silicon and kept at 1600 °C for 2 h in vacuum. The SiC/Si composites were obtained due to the produced carbothermal reaction. As expected, the resulting electrical conductivity of these composites increased with the temperature and with the silicon content.

First principles simulation of liquid silicon

1993 ◽  
Vol 88 (5) ◽  
pp. 381-385 ◽  
Author(s):  
James R. Chelikowsky ◽  
N. Binggeli
Keyword(s):  
First Principles ◽  
Liquid Silicon

Sound velocity in liquid silicon

1979 ◽  
Vol 72 (2) ◽  
pp. 153-154 ◽  
Author(s):  
N.M. Kéita ◽  
S. Steinemann
Keyword(s):  
Sound Velocity ◽  
Liquid Silicon

Arsenic Implant Activation and Redistribution in P-Type Silicon Induced by Pulsed Electron Beam Annealing

1982 ◽  
Vol 13 ◽  
Author(s):  
D. Barbierf ◽  
M. Baghdadi ◽  
A. Laugier ◽  
A. Cachard
Keyword(s):  
Electron Beam ◽  
Carrier Concentration ◽  
Beam Energy ◽  
Energy Deposition ◽  
Liquid Silicon ◽  
Electron Beam Energy ◽  
Pulsed Electron Beam ◽  
Highly Active ◽  
P Type ◽  
Fluence Range

ABSTRACTIn this work Pulsed Electron Beam Annealing has been used to Sctivaye As implanted in (100) and (111) silicon (140 keV- 1015 cm−2 ). With a selected electron beam energy deposition profile excellent regrowth layer quality and As activation has been obtained in the 1.2–1.4 J/cm2 fluence range. As redistribution is conistent with the melting model assuming a diffusivity of 10−4 cm2/s in liquid silicon. As losses might slightly reduce the carrier concentration near the surface in the case of (100) silicon. However a shallow and highly active N+ layer have been achieved with optimized PEBA conditions.

Formation of dense silicon carbide by liquid silicon infiltration of carbon with engineered structure

2008 ◽  
Vol 23 (5) ◽  
pp. 1237-1248 ◽  
Author(s):  
Jesse C. Margiotta ◽  
Dajie Zhang ◽  
Dennis C. Nagle ◽  
Caitlin E. Feeser
Keyword(s):  
Silicon Carbide ◽  
Bulk Density ◽  
Phenolic Resin ◽  
Pore Diameter ◽  
Chemical Reactivity ◽  
Liquid Silicon ◽  
Crystalline Cellulose ◽  
Carbon Preform ◽  
Median Pore ◽  
The Ideal

Fully dense and net-shaped silicon carbide monoliths were produced by liquid silicon infiltration of carbon preforms with engineered bulk density, median pore diameter, and chemical reactivity derived from carbonization of crystalline cellulose and phenolic resin blends. The ideal carbon bulk density and minimum median pore diameter for successful formation of fully dense silicon carbide by liquid silicon infiltration are 0.964 g cm−3 and approximately 1 μm. By blending crystalline cellulose and phenolic resin in various mass ratios as carbon precursors, we were able to adjust the bulk density, median pore diameter, and overall chemical reactivity of the carbon preforms produced. The liquid silicon infiltration reactions were performed in a graphite element furnace at temperatures between 1414 and 1900 °C and under argon pressures of 1550, 760, and 0.5 Torr for periods of 10, 15, 30, 60, 120, and 300 min. Examination of the results indicated that the ideal carbon preform was produced from the crystalline cellulose and phenolic resin blend of 6:4 mass ratio. This carbon preform has a bulk density of 0.7910 g cm−3, an actual density of 2.1911 g cm−3, median pore diameter of 1.45 μm, and specific surface area of 644.75 m2 g−1. The ideal liquid silicon infiltration reaction conditions were identified as 1800 °C, 0.5 Torr, and 120 min. The optimum reaction product has a bulk density of 2.9566 g cm−3, greater than 91% of that of pure β–SiC, with a β–SiC volume fraction of approximately 82.5%.

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