Results of X‐ray investigations of Hg1–x Cdx Te (x = 0.25) epitaxial layers after single and two‐stage arsenic ion implantation with the energy E = 100 keV are represented. It has been established that for doses D1 = 2 × 1014 ions/cm2 and D2 = (2 × 1014 + 1015) ions/cm2 the Frenkel pair (anion vacancy + interstitial mercury atom) generation is the most probable process. The model of a possible system of structural defects in the near‐surface layers of ion‐implanted structures Hg1–x Cdx Te is proposed. The model allows for the presence of certain dimensions and concentrations of both growth and new defects – the Frenkel pairs, cluster formations and dislocation loops formed under ion radiation. The calculated deformation profiles are complex in shape with characteristic peaks at the depth of maximum nuclear power ion loss. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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This paper presents the conceptual stages of the simulation and development of a modified transceiver antenna for a high-power pulsed nuclear quadrupole resonance (NQR) detector of explosives containing the 14N isotope. At a frequency of 4.645 MHz, better characteristics are obtained using a nine-turn coil shaped as half of a Fermat spiral with an outer radius of 75 mm. Using a COMSOL Multiphysics numerical parametric simulation and a materials browser, it was possible to calculate a physical system with parameters as close to reality as possible. According to the results of the experimental studies of the radio frequency (RF) energy, the proposed antenna features an increase in the working area compared to a similar antenna, the topology of the conductive coil of which has the form of an Archimedean spiral. The resulting diagrams of the distribution of the magnetic induction also indicate that the topology of the electromagnetic (EM) field does not depend on the orientation of the sample under study relative to the axis of the radial symmetry observed in square–rectangular planar antennas.

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The results of X-ray AFM, SEM, and SIMS studies of near-surface regions of HgCdTe graded-gap epitaxial layers obtained by high-temperature annealing in vapour of the main components have been presented. We used ISOVPE layers of HgCdTe grown on CdTe substrates the surface of which was implanted by As ions. The AFM investigation has shown that the morphology of surfaces of HgCdTe structures obtained at the same conditions is significantly influenced by the crystal orientation of the initial substrates of CdTe. By means of SIMS and SЕМ analysis a substantial increase of the molar content of HgCdTe solid solution on the surface of ion-implanted epitaxial layers after high-temperature annealing has been observed. It is shown that large gradients of composite HgCdTe solid solution are formed in the nearsurface regions of the epitaxial layers due to small changes in the thermodynamically equilibrium conditions of the process of high-temperature annealing.