The silicon isotope composition of three carbonaceous chon-drites (Orgueil, Murchison, and Vigarano), three ordinary chon-drites (Parnallee, Bovedy, Bremervörde), one enstatite chondrite (Sahara 97158) and nine terrestrial samples (7 peridotites, 1 mid-ocean ridge basalt, 1 ocean island basalt) were measured to high precision and accuracy using the high resolution Nu Plasma 1700 MC-ICPMS at ETH...

We have demonstrated a new technique to transform bulk materials into one-dimensional nanostructures. We have shown that p-type Si nanotubes (SiNTs) can be grown by a simple dual RF plasma treatment of p-type Si substrates at 500 °C. These SiNTs have diameters of ∼50-80 nm with tubular wall thickness of ∼10-15 nm. The use of Cu vapor and reactive plasma has enabled the growth of these SiNTs ins...

Damage build up and amorphization in Si, induced by 25 keV Si 5 cluster ions and similar mass Cs ions have been studied using transmission electron microscopy and channeling Rutherford backscattering spectrometry. Amorphization is found to be a nucleation and growth process, under the direct impact mechanism. A transition to a completely amorphized state is indicated at a dose of around 17 eV/a...

We demonstrate lithographically fabricated Si nanowire field effect transistors (FETs) with long Si nanowires of tiny cross sectional size (∼3-5 nm) exhibiting high performance without employing complementarily doped junctions or high channel doping. These nanowire FETs show high peak hole mobility (as high as over 1200 cm(2)/(V s)), current density, and drive current as well as low drain leaka...

The in situ SiC/Al composites were fabricated in Al-Si-C systems with different Si/C mass ratios and holding time by the method of combustion synthesis and hot press consolidation. The influences of Si/C mass ratio and holding time on the phase constitution, microstructure, and hardness of the composites were investigated. The results indicate that the increase of Si/C mass ratio leads to more ...

A powerful characterization technique, pulse capacitance-voltage (CV) technique, was used to investigate oxide traps before and after annealing for lanthanide zirconium oxide thin films deposited on n-type Si (111) substrates at 300 °C by liquid injection Atomic Layer Deposition (ALD). The results indicated that: (1) more traps were observed compared to the conventional capacitance-voltage char...

A 47-year-old woman gave a 1-month history of persistent oedema of the eyelids and lips. There was no apparent relationship to externa] triggering factors, and she liad no known history of sensitization or atopy and no relevant personal or family history. For 1 year she had been wearing a partial removable methacrylate prosthesis (Fig. 1). This was mainly composed of cobalt and chromium (Co: 60...

A longstanding challenge in production chemistry is the development of catalytic methods for the transformation of carbon dioxide into useful chemicals. Silane and borane promoted reductions can be fined-tuned to provide a number of C1-building blocks under mild conditions, but these approaches are limited because of the production of stoichiometric waste compounds. Here we report on the conver...

We investigate the impact of water on the optical absorption of prototypical silicon clusters. Our clusters contain 5 silicon atoms, tetrahedrally coordinated and passivated with either hydrogen or oxygen. We approach this complex problem by assessing the contributions of three factors: chemical reactivity, thermal equilibration, and dielectric screening. We find that the silanone (Si=O) functi...

The elastic response, including the spring constant, of individual Si helical-shape submicron springs, was measured using a tip-cantilever assembly attached to a conventional atomic force microscope. The isolated, four-turn Si springs were fabricated using oblique angle deposition with substrate rotation, also known as the glancing angle deposition, on a templated Si substrate. The response of ...