Silicon

About: Silicon is a research topic. Over the lifetime, 196073 publications have been published within this topic receiving 3038411 citations. The topic is also known as: element 14 & Si.

Micrometre-scale silicon electro-optic modulator

Abstract: Metal interconnections are expected to become the limiting factor for the performance of electronic systems as transistors continue to shrink in size. Replacing them by optical interconnections, at different levels ranging from rack-to-rack down to chip-to-chip and intra-chip interconnections, could provide the low power dissipation, low latencies and high bandwidths that are needed. The implementation of optical interconnections relies on the development of micro-optical devices that are integrated with the microelectronics on chips. Recent demonstrations of silicon low-loss waveguides, light emitters, amplifiers and lasers approach this goal, but a small silicon electro-optic modulator with a size small enough for chip-scale integration has not yet been demonstrated. Here we experimentally demonstrate a high-speed electro-optical modulator in compact silicon structures. The modulator is based on a resonant light-confining structure that enhances the sensitivity of light to small changes in refractive index of the silicon and also enables high-speed operation. The modulator is 12 micrometres in diameter, three orders of magnitude smaller than previously demonstrated. Electro-optic modulators are one of the most critical components in optoelectronic integration, and decreasing their size may enable novel chip architectures.

The chemistry of organic silicon compounds

Abstract: Historical overview and comparison of silicon with carbon, J.Y.Corey theoretical aspects of organosilicon compounds, Y.Apeloig structural chemistry of organic silicon compounds, W.S.Sheldrick dynamic stereochemistry at silicon, R.J.P.Corriu et al thermochemistry, R.Walsh analysis of organosilicon compounds, T.R.C.Crompton positive and negative ion chemistry of silicon-containing molecules in the gas phase, H.Schwarz NMR spectroscopy of organosilicon compounds, E.A.Williams photoelectron spectra of silicon compounds, H.Bock and B.Solouki general synthetic pathways to organosilicon compounds, L.Birkofer and O.Stuhl recent synthetic application of organosilanes, G.L.Larson acidity, basicity and complex formation of organosilicon compounds, A.R.Bassindale and P.G.Taylor reaction mechanisms of nucleophilic attacks at silicon, A.R.Bassindale and P.G.Taylor activating and directive effects of silicon, A.R.Bassindale and P.G.Taylor the photochemistry of organosilicon compounds, A.G.Brook trivalent silyl ions, J.B.Lambert and W.J.Schulz Jr multiple bonds to silicon, G.Raabe and J.Michl bio-organic chemistry, R.Tacke and J.Linoh polysilanes, R.West hypervalent silicon compounds, R.J.P.Corriu and J.C.Young siloxane polymers and copolymers, T.C.Kendrick organosilicon derivatives of phosphorus arsenic, antimony and bismuth, D.A.Armitage chemistry of compounds with silicon-sulphur, silicon-selenium and silicon-tellurium bonds, D.A.Armitage transition-metal silyl derivatives, T.D.Tilley the hydrosilylation reaction, I.Ojima.

Optical gain in silicon nanocrystals

Abstract: Adding optical functionality to a silicon microelectronic chip is one of the most challenging problems of materials research. Silicon is an indirect-bandgap semiconductor and so is an inefficient emitter of light. For this reason, integration of optically functional elements with silicon microelectronic circuitry has largely been achieved through the use of direct-bandgap compound semiconductors. For optoelectronic applications, the key device is the light source--a laser. Compound semiconductor lasers exploit low-dimensional electronic systems, such as quantum wells and quantum dots, as the active optical amplifying medium. Here we demonstrate that light amplification is possible using silicon itself, in the form of quantum dots dispersed in a silicon dioxide matrix. Net optical gain is seen in both waveguide and transmission configurations, with the material gain being of the same order as that of direct-bandgap quantum dots. We explain the observations using a model based on population inversion of radiative states associated with the Si/SiO2 interface. These findings open a route to the fabrication of a silicon laser.

High Performance Silicon Nanowire Field Effect Transistors

Abstract: Silicon nanowires can be prepared with single-crystal structures, diameters as small as several nanometers and controllable hole and electron doping, and thus represent powerful building blocks for nanoelectronics devices such as field effect transistors. To explore the potential limits of silicon nanowire transistors, we have examined the influence of source-drain contact thermal annealing and surface passivation on key transistor properties. Thermal annealing and passivation of oxide defects using chemical modification were found to increase the average transconductance from 45 to 800 nS and average mobility from 30 to 560 cm 2 /V‚s with peak values of 2000 nS and 1350 cm 2 /V‚s, respectively. The comparison of these results and other key parameters with state-of-the-art planar silicon devices shows substantial advantages for silicon nanowires. The uses of nanowires as building blocks for future nanoelectronics are discussed.