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Although electroless contacts are the most used contacts on II-VI semiconductor materials (CdTe family) to solve many problems, they are difficult to understand and to control. For this paper, we have chosen two II-VI materials, CdTe and ZnTe, and three metals: Au, Pt, and Pd. For the characterization methods, we have chosen Rutherford backscattering (RBS), secondary ions mass spectroscopy (SIMS), and partially Auger for the contacts and interface structures, stoechiometry, and composition profiles. Electrical measurements, PICTS and TEES, are done to find out defect level concentrations and nature, as well as the possible correlation with the composition concentrations. As first parameter change, we have chosen the solution dilution in the electroless deposition process, while the other parameters were frozen. This allows us to drive and to see a drastic variation in the profile of the metal, the two constituent materials and the oxygen in the metal layer. The same has been seen at the interface where the [V.sub.Cd] concentration profile shows sensible variation too. We have found a clear connection with specific electrical defect concentrations. The validity of these concentration measurements in the bulk are then subject to questions. The comparison with evaporated contacts is done for bulk and surface property separations. Contact induced stress is simulated by static pressure in longitudinal and transversal direction. We have driven out the induced defect natures and concentrations. The limit of operation under stress is also given. Index Terms--CdTe, defect, electroless deposition thin films, nuclear detectors, PICTS, RBS, semiconductors, SIMS, stress, ZnTe.

The characterization of Nanosized Ni0.5Zn0.5RuxFe2−xO4 (0.00 ≤ x ≤ 0.015), prepared by the wet chemical coprecipitation method, is reported in the current investigation. X-ray powder diffraction (XRD) analysis has confirmed the formation of a single phased spinel cubic structure. While transmission electron microscopy (TEM) studies have shown an increase in the particle size for high content of Ru3+ doping. The elemental composition of all samples was investigated using energy dispersive x-ray (EDX) measurements. The results showed a reciprocal relation between the Fe3+ and Ru3+ contents, suggesting the successful substitution of Ru3+in Fe3+ sites. UV–Vis spectroscopy studies, via Urbach energy analysis, proposed a perturbation in the band structure of Ni0.5Zn0.5Fe2O4 induced by Ru3+ substitution, affecting both the direct and indirect bandgap energies. Excitation wavelength-dependent photoluminescence (PL) studies, presented for the first time, have shown a strong dependence of the emission spectra on both the excitation wavelength and Ru3+ doping. The PL analysis suggests the utilization of Ni0.5Zn0.5RuxFe2−xO4 as a candidate for photocatalytic applications. Furthermore, VSM studies, have shown a transition from superparamagnetic to soft ferromagnetic for Ru3+ doped samples. The saturation magnetization, coercivity, and effective anisotropy were enhanced as a result of Ru3+ doping. Finally, photocatalysis experiments have shown an enhancement of the degradation rate of nitrobenzene for the sample with x = 0.0125 with the ability of magnetic recycling, in agreement with the PL and VSM studies. [ABSTRACT FROM AUTHOR]

The effect of nanosized particles NiO addition on the Vickers microhardness of polycrystalline SmBa2Cu3O7-δ was investigated. Various amounts of nanosized particles NiO (x = 0.00, 0.02, 0.04, 0.08, and 0.12 wt%) were added to SmBa2Cu3O7-δ prepared by the solid-state reaction method. Sample characterizations were carried out using X-ray powder diffraction (XRD), particle induced X-ray emission (PIXE), Rutherford backscattering (RBS), and scanning electron microscopy (SEM). The nanosized particle addition does not influence the orthorhombic structure of SmBa2Cu3O7-δ, whereas it affects the oxygen content δ. The electrical and mechanical properties of (NiO)xSmBa2Cu3O7-δ samples were measured using four-standard probe technique and Vickers microhardness in order to investigate the effect of NiO nanosized particles on superconducting transition temperature and Vickers microhardness number Hv. The Vickers microhardness data were analyzed using Hays and Kendall (HK), elastic plastic deformation (EPD), and modified proportional specimen resistance (MPSR) models. The analysis showed that the MPSR model was found to be the best to describe the behavior of Hv. [ABSTRACT FROM AUTHOR]

This paper presents experimental results on post insulators subjected to ultra high dc voltages in the range of 1 to 4.8 MV. The behavior of new and aged insulators has been studied recently during diagnostic and accelerated aging tests, in order to characterize both their withstand and recovery voltages, as well as estimate their remaining life time. Estimation of their remaining life time enables a better prediction of maintenance intervals, thus avoiding unnecessary and costly downtime periods. Measurements of the recovery voltage also have been performed on insulators presenting defects, following dielectric failure in service. The results of the accelerated aging tests carried out demonstrates a faster assessment of the post insulators performance.