This article describes how to extract accurate information about a plasma from a capacitively coupled planar probe that is biased using pulsed radio-frequency excitation. The conditions necessary to observe correct saturation of the probe current are investigated, particularly the use of correct geometry and biasing for the guard ring. With these precautions the probe is an effective diagnostic for electron tail temperature at energies beyond those probed by conventional cylindrical probes. The dynamic response of the probe is investigated using conventional sweep voltages and shows the onset of displacement current and inertial effects associated with ions and electrons. In addition the effect of insulating films on the probe surface is examined, showing how the probe continues to operate even when it is coated. Characteristic changes caused by the presence of an insulating film give information about its electrical properties and its thickness.

The use of diamond as a material for high power electronics requires high‐purity monocrystalline thick diamond films. Hence it is extremely important to have perfect control of the morphology during the entire growth process, so that the useable surface be maximized and residual stresses (which may cause cracking of the sample during the growth process) be limited. To assist in this work, a 3D geometric growth model has been recently developed, taking into account the growth rate of the different crystallographic planes: {100}, {110}, {111}, and {113}. The knowledge of the growth rate along the different directions as a function of growth parameters (substrate temperature, methane concentration, and nitrogen content in the gas phase) was the missing link between simulations and effective thick film processing. This knowledge is here embodied in the measurements displayed in this paper. In particular, we report on a way of limiting the occurrence of specific facets with deleterious effects on stress and crystal cracking probability. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

International audienceThe permanent operation of a 3 axes magnetometer in the LSBB below 550 m of calcite rock is a unique system of magnetic observation: a rejection rate better than 3 fT/Hz over 40 Hz. The observation of magneto-ionosphere responses to wave emissions both at the epicentre and at their arrival at LSBB for earthquakes of magnitude larger than 3 is reported. A simple model predicts the starting time of these events. These results are compared with those provided by Doppler sounders for ionosphere responses to Rayleigh waves

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