Easy and reproducible method for making sharp tips of Pt/IrSharp tips for various modern microscopies, such as field-ion microscopy ͑FIM͒ and scanning tunneling microscopy ͑STM͒, can be prepared by electropolishing in solutions which are relatively innocuous for the environment as well as the researcher, compared to the often hazardous solutions still in widespread use. We have made measurements of polishing times as a function of solution and voltage parameters and we report conditions for electropolishing sharp tips of Pt, Ir, Au, Pd, and Rh using relatively benign solutions.

The thermal properties of the phase-change chalcogenide alloy Ge2Sb2Te5 in its three phases (amorphous, cubic, and hexagonal) and of Si3N4 and SiO2 have been studied to obtain reliable values for device modeling. Thermal conductivity was determined, along with a quantitative estimation of the thermal resistances of the layers’ interfaces, not negligible for highly scaled devices. Electrical resistivity of the chalcogenide material has also been investigated during the phase transition by in situ measurement at constant heating rate.

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The thickness dependence of the dielectric properties of epitaxial BaTiO3 thin films was investigated for thicknesses ranging from 15 to 320 nm. The films were deposited by low-pressure metalorganic chemical vapor deposition on (100) MgO substrates. The relative dielectric permittivity and the loss tangent values decreased with decreasing thickness. High-temperature dielectric measurements showed that with decreasing film thickness, the ferroelectric-to-paraelectric transition temperature decreased, the relative dielectric permittivity decreased, and the phase transition was diffuse. The c/a ratio also decreased with decreasing film thickness. The observed behavior for epitaxial films of BaTiO3 was attributed to the presence of strain in the films.