Carbon‐coated natural graphite has been prepared by thermal vapor decomposition treatment of natural graphite at 1000°C. Natural graphite coated with carbon showed much better electrochemical performance as an anode material in both propylene carbonate‐based and ethylene carbonate‐based electrolytes than “bare” natural graphite. The effect of carbon coating on the electrochemical performance was investigated by solid‐state 7normalLi‐NMR in conjunction with standard electrochemical techniques. © 2000 The Electrochemical Society. All rights reserved.

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A novel spectroscopy technique based on modulated photoconductivity measurements with varying illumination level has been applied to investigate the capture coefficients and the energy distribution of defect states in undoped amorphous silicon. From the experimental data, charged and neutral defect distributions are clearly resolved according to their own capture coefficients. The carrier capture process as well as the defect formation mechanism are both quantitatively discussed.

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The synthesis of a novel anion-exchangeable nanostructured aminophenylsilica with a well-ordered layer geometry was demonstrated by utilizing the sol-gel reaction of p-aminophenyltrimethoxysilane in the presence of an anionic surfactant micelle under acidic conditions

An organic aqueous solution of metal acetylacetonate precursors was subjected to spray pyrolysis in order to fabricate SrAl2O4:Eu (SAO) nanoparticles. Non‐agglomerated luminescent SAO nanoparticles, having a spherical shape with a size of 10–30 nm, were achieved in a single step, while only submicrometer‐sized SAO particles were obtained from the conventional ultrasonic pyrolysis of the metal nitrates. Without any post‐annealing process, the as‐prepared SAO nanoparticles were observed to exhibit a strong photoluminescence, which is comparable with that of the submicrometer‐sized SAO particles. A mechanism for the formation of the nanoparticles is also discussed.

A broad beam ion source using a microwave electron cyclotron resonance (ECR) discharge has been newly developed, giving high reliability in operation. The ion source operates at gas pressures higher than about 3×10-5 Torr, and an ion current density of 1 mA/cm2 is obtained at an ion extraction voltage of 1000 V. By introducing C4F8 and SiCl4 into the ion source, SiO2 and Al are etched at rates greater than 1000 Å/min, with high selectivities and high-accuracy pattern transfer.