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Gas-filled proportional detectors of ionizing radiation often contain such elements as thin anode wire, which make them sensitive to external acoustic or vibrational impact. This study investigates such sensitivity for the case of the proportional γ-radiation detectors filled with high-purity xenon gas. The detector demonstrates a dependence of its signal noise on the external acoustic wave frequency, the character of which most likely depends on the design of the detector, i.e. on such parameters as diameter and tension strength of the anode wire, etc. To suppress the negative impact of acoustic noise on the characteristics of the detector, the detector digital signal is processed in a Field-Programmable Gate Array board. The authors investigate the algorithm of «time windows», which allows separating (filtering) low-frequency noise in the output signal of a gas-filled detector, which arises due to the influence of external sound, from the useful signal, i.e. the ionization pulses. This approach allows performing spectral measurements of γ-radiation with a significant acoustic noise background, when detectors with a conventional analog spectrometric channel cannot handle the task.

The article is dedicated to the numerical simulations of thin-layer structures based on CdTe semiconductors, which can be fabricated by using low-cost technologies. Structures Mo/Au/CdS/CdTe/Au, and their modifications, with different thicknesses of the main layers are investigated. The possibility of creating a detector of ionizing radiation based on these structures, which has selective properties with respect to the radiation type, and very low operation voltage, is shown. The detection efficiencies of α -, β -, and γ -radiation in different energy ranges were calculated based on the obtained values of energy losses of ionizing particles, which are proportional to the output signal of the detector. The use of such detectors, together with a solid-state converter made of boron carbide containing either natural boron nat B or boron enriched with the 10 B isotope up to 95 % , for the detection of thermal neutrons was also studied. It was shown that the structures could be used to create α -particle spectrometers, given that the CdTe thickness is tailored to the highest expected α -particle energy. Detectors with thin CdTe (1–5 μ m) can be successfully used in the counting mode. For neutron detection, stacking multiple single structures into sandwich structures was proposed and investigated. In such a configuration, the detector qualities were markedly improved: the efficiency of neutron detection reached ∼ 60 % , while the sensitivity to the background γ - and β -radiation was ∼ 100 times lower than that for neutrons. The very low sensitivity of the simulated neutron detectors to the neutron incidence angle was shown. [ABSTRACT FROM AUTHOR]

The influence of pulsed helium plasma irradiation, with a 10 μs duration and a surface energy load of 0.2 MJ m-2, on the elemental and phase composition, surface morphology and crystal structure of thin-film heterosystems based on CdS/CdTe was studied. The cadmium sulphide and cadmium telluride layers were deposited by condensation via a hot wall method onto a glass substrate covered with an FTO layer. It was found that after one pulse, the device structure remains in working condition. An increase in the irradiation dose leads to surface sputtering, the formation of through pores 0.5 – 2 μm in size, and a microcracks network with two characteristic scales. One crack network is formed in the glass substrate, and the second network is formed with cracks in the CdTe film. It is shown that the thermal effect of plasma stimulates the diffusion of sulphur; as a result, the proportion of CdTe1-xSx solid solutions formed in the process of obtaining the CdS/CdTe heterosystem increases. In addition, the sulphur content increases in these solid solutions, which leads to their decomposition with the separation of the CdS1-yTey solid solution phase. These solid solutions migrate to the CdTe surface through cracks and are observed as separate crystals. [ABSTRACT FROM AUTHOR]

In this work, the ability of CdTe/CdS thin-film device structures prepared by the hot-wall method to detect ionizing radiation was investigated. The samples were fabricated with a structure typical of CdTe/CdS-based solar cells and exhibit radiation sensitivity even without the application of an external voltage. This allows such structures to be used as low-voltage radiation sensors. An investigation of the radiation resistance of the structures, namely, the effect of irradiation with high-intensity hydrogen plasma H2+ on the crystal structure and performance, was carried out. It was shown that the device structures remained operational after two plasma pulses at an ion density of 2 × 1023 m−2 and an energy density of up to 0.2 MJ/m2. With further exposure to plasma, the device structures deteriorated, first, due to gradual sputtering off of the back contact, and, second, as a result of diffusion processes that occurred when the structures were heated to high temperatures, due to which the entire volume of the CdTe base layer got converted into a CdSxTe1−x solid solution. [ABSTRACT FROM AUTHOR]

Implantation of hydrogen into silicon with subsequent annealing (Smart-Cut Technology) is applied to produce microelectronic devices. Improved characteristics of the resulting structures were achieved by using implantation of deuterium instead of hydrogen. The nanoindentation technique is widely used to measure the hardness H and elasticity modulus E of materials at the nanoscale. The aim of the present work is to investigate the influence of deuterium ion implantation dose on the structure and mechanical properties of single crystal silicon at the nanoscale. The influence of the deuterium ion implantation with an implantation dose ranging from 2×1015 to 1×1018 D/cm² on the structure and mechanical properties of single crystal silicon at the nanoscale has been investigated. Polished (111) silicon samples were implanted at 293 K by using a deuterium ion beam with an ion energy of 24 keV. It was shown by Raman spectroscopy that, depending on the implantation dose, three structural states are formed in silicon: a solid solution of deuterium (D) in Si, a solid solution mixed with the Si amorphous phase, and an amorphous state (a-Si:D) only. Thermal desorption (TD) spectroscopy shows that at low implantation doses, the deuterium TD spectra exhibit a single peak with a maximum at Tmax ~ 575 K. At doses above 5×1017 D/cm², a lowtemperature peak with a maximum at 500 K appears that is indicative of the formation of amorphous hydrogenated silicon a-Si:D. Nanoindentation tests have shown that in the regime of full plasticity in the indenter contact region ( 100 nm), the formation of deuterium solid solution in Si causes an increase in the sample surface hardness up to 14.1 GPa. The surface hardness sharply decreased down to 3.6 GPa with the a-Si:D layer formation. [ABSTRACT FROM AUTHOR]

Previous work on CdS–CuInSe2 (CIS) solar cells, which reported distortions of their current-voltage (J–V) curves under red illumination, is expanded in this work to include CdS–CuIn1-xGaxSe2 cells with variable Ga and CIS cells with variable CdS thickness. Different amounts of J–V distortion were observed in these cells under red light. The details are in good agreement with predictions of a photodiode model, in which a secondary barrier caused by the positive conduction-band discontinuity (spike) at the buffer–absorber interface is responsible for the current limitation. The illumination of the cell with high-energy photons lowers the barrier due to buffer photoconductivity, and thus removes the J–V distortion. [ABSTRACT FROM AUTHOR]

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