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We report on specific-heat measurements (0.1 K< T<2K) of heavily neutron-irradiated (4.8×10 and 3×10 n/cm) and as-received Si single crystals and of an evaporated amorphous Si film. The sample irradiated with the higher dose contains 6% amorphous regions, the other remains crystalline. The magnitude of the specific heat increases with 'amorphicity'. However, already in the crystalline sample the specific heat exceeds the Debye contribution. We attribute the excess specific heat to exchange-coupled dangling bonds located at defects in crystalline environments and - for the amorphous sample - to dangling bonds in the amorphous network. [ABSTRACT FROM AUTHOR]

A differential method to compute, with high accuracy, the resonant frequency of a dielectric body with an axis of revolution and placed between two conducting plates is described. The propagation equations, projected on a Fourier basis, are integrated by the Adams-Moulton predictor-corrector algorithm and matched to the modified Bessel expansion of the field. Numerical results obtained for the cylinder shape are compared with those obtained by a modal theory, exhibiting an accuracy better than 10. Results for a dielectric sphere are given as another application. [ABSTRACT FROM AUTHOR]

The electrical properties of n-window layers in p-i-n a-Si:H solar cells were characterised as a function of n-layer thickness, $$d_{n^ + } $$ , by measuring firstly the activation energy E of the dark conductivity and secondly the built-in potential V of the cells. E was found to increase with decreasing $$d_{n^ + } $$ attaining values as high as 0.8 eV for $$d_{n^ + } $$ ≅5nm; bulk values, e.g. E ≅. 2eV in the amorphous and E<0.01 eV in the microcrystalline case, were only observed for $$d_{n^ + } $$ >20nm and for $$d_{n^ + } $$ >200nm, respectively. In contrast, V did not depend on $$d_{n^ + } $$ at all and was further found to be consistent with expectations based on the Fermi level positions in bulk n and p-material. As a consequence E in very thin films can no longer be considered as a measure of ( E −E), the distance of the Fermi level from the conduction band edge. The apparent inconsistency inherent to the E and the V results can be resolved by assuming that the deposition of the n-material proceeds via the growth and coalescence of small islands. [ABSTRACT FROM AUTHOR]

The current work considers the effect of geometry, other than the ideal Taylor cone, on space charge and axial fields of liquid metal ion sources. Solutions of the spacecharge equation for the concentric sphere and hyperboloidal-planar models of a liquid emitter demonstrate a rather dramatic dependence of the space charge and axial fields on the geometry of the emitting surface. [ABSTRACT FROM AUTHOR]

Vibrations in circular, convex AT-cut bevelled-design quartz resonators are experimentally investigated. The theory is compared with the experimental data of x-ray diffraction topography. Very good agreement is established between theory and experiment. [ABSTRACT FROM AUTHOR]