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The morphology, microstructure, chemistry, electronic properties, and electrochemical behavior of a boron-doped nanocrystalline diamond (BDD) thin film grown on quartz were evaluated. Diamond optically transparent electrodes (OTEs) are useful for transmission spectroelectrochemical measurements, offering excellent stability during anodic and cathodic polarization and exposure to a variety of chemical environments. We report on the characterization of a BDD OTE by atomic force microscopy, optical spectroscopy, Raman spectroscopic mapping, alternating-current Hall effect measurements, X-ray photoelectron spectroscopy, and electrochemical methods. The results reported herein provide the first comprehensive study of the relationship between the physical and chemical structure and electronic properties of a diamond OTE and the electrode's electrochemical activity.

This letter reports the thermoelectric properties of Bi-doped Mg2Si0.4Sn0.6 thermoelectric materials. It was found that the ZTs of this material could be greatly enhanced by Bi-doping. Analyses on the transport properties showed that the power factors of the material were enhanced while the lattice thermal conductivities were reduced by Bi-doping. The reduction of the lattice thermal conductivity was likely caused by the interstitial Bi impurities. A peak ZT ≈ 1.55 at 773 K was obtained.

High quality single crystal boron-doped diamond films are deposited in a microwave plasma-assisted CVD reactor with feedgas mixtures including hydrogen, methane, diborane, and carbon dioxide at reactor pressures of 160 Torr. The effect of diborane levels and other growth parameters on the incorporated boron levels are investigated, and the doping efficiency is calculated over a wide range of boron concentrations. The boron level is investigated using infrared absorption, and compared to SIMS measurements, and defects are shown to affect the doping uniformity.

A temperature dependent Hall Effect measurement system with software based data acquisition and control was built and tested. Transport measurements are shown for boron-doped single crystal diamond (SCD) films deposited in a microwave plasma-assisted chemical vapor deposition (MPCVD) reactor. The influence of Ohmic contacts and temperature control accuracy are studied. For a temperature range of 300K-700K IV curves, Hall mobilities and carrier concentrations are presented.