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This work considers the manifestation of spontaneous breakdowns of Geiger-Mueller counters. This is an experimental type of work. The reasons leading to the spontaneous breakdowns of Geiger-Mueller counters have been analysed under controlled laboratory conditions. The experiments were carried out under the “constant voltage”. The tested Geiger-Mueller chambers were commercial chambers of the radial electric field and homogenous electric field. The experimental-statistical methods were used in order to choose the chambers with identical features (with 0.1 % of statistical reliability).The results of experiments showed that the spontaneous breakdown of the Geiger-Mueller counter happens even in the conditions of shielding. They also showed that those breakdowns have cumulative features. The reason for that is a positive feedback between the spontaneous breakdowns. The explanation is confirmed and quantified by the working gas filtering experiments. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171007]

The variations in the threshold voltage shift in p-channel power VDMOSFET during the gamma ray irradiation was investigated in the dose range from 10 to 100 Gy. The investigations were performed without the gate bias and with 5 V gate bias. The devices with 5 V gate bias exhibit a linear dependence between the threshold voltage shift and the radiation dose. The densities of radiation-induced fixed and switching traps were determined from the sub-threshold I-V characteristics using the midgap technique. It was shown that the creation of fixed traps is dominant during the irradiation. The possible mechanisms responsible for the fixed and switching traps creation are also analyzed in this paper. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171007]

The paper examines the effects of radiation on the electrical characteristics of monocrystalline silicon and germanium. Samples of monocrystalline silicon and germanium are irradiated under controlled laboratory conditions in the field of neutron, X- and g-radiation. Change of the samples' specific resistance was measured dependent on the radiation dose with the type of radiation as a parameter. Next, the dependence of the samples resistance on temperature was recorded (in the impurities region and in intrinsic region) with the previously absorbed dose as a parameter. The results were statistically analyzed and explained on the basis of radiation effects in solids. The results are compared with those obtained by using Monte Carlo method. A good agreement was confirmed by the mentioned experimental investigation. [Projekat Ministarstva nauke Republike Srbije, br. 171007]

Photo and nuclear radiation induced processes are considered through the interaction of radiation with semiconducting, metallic and other materials, including the scintillator materials. The improvement of component efficiency by the use of quantum generators, trimming and hybrid processes with nuclear radiation has been analyzed. The studied processes can be positive or negative depending on application. Besides the experimental approach to the processes and chosen interactions, the analytical description of our experiments, as well as ones from other references, has been performed. The contemporary couplings between the nuclear physics, laser techniques and respective dosimetric aspects have been considered. [Projekat Ministarstva nauke Republike Srbije, br. II45003 i br. TP 35046]

This paper discusses the possibility of applying the F-test and double t-test in problems related to the identification of number of radioactive isotopes in a contaminated area by using only counters for radiation detection. The descriptions of the F-test and the double t-test are given along with the corresponding tabular values that enable their implementation. Finally, the experiment is presented via two radioactive samples. The results of the experiment were treated in the manner proposed in the paper and satisfactory results were obtained. [Projekat Ministarstva nauke Republike Srbije, br. 171007]

This paper deals with the flash memory reliability in terms of the ionizing radiation effects. In fact, the reliability of flash memory depends on physico-chemical restrictions of electrostatic nature due to the effects of ionizing radiation. The presented results are actual as a high degree of integrated components miniaturization affects the memory sensitivity, while the role of memories in the solar cells management system for space flights is increasing, so that the effects of ionizing radiation may cause changes in the stored data or the physical destruction of the flash memory components. [Projekat Ministarstva nauke Republike Srbije, br.171007]

This paper presents the behavior of PIN photodiodes after combined gamma and neutron irradiation. Different types of PIN photodiodes have been exposed first to gamma and then to neutron irradiation. I-V characteristics (current dependence on voltage) of photodiodes have been measured after each of these irradiations. It has been noted that the photocurrent level after the neutron irradiation is higher than before it, which is not consistent with the current theories about the effects of neutron radiation on semiconductors. In order to explain this behavior of the photodiodes, the Monte Carlo simulation of photon transport through the material has been used. It is proposed that a possible cause for current enhancement are defects in semiconductor created by gamma irradiation and effects of neutron irradiation on these defects. The results can be explained by an intercentre transfer of charge between defects in close proximity to each other. The aim of this paper is to investigate the improvement possibilities of the I-V characteristics of PIN photodiodes, and photodetectors in general, damaged by gamma irradiation. [Projekat Ministarstva nauke Republike Srbije, br. 171007]

Absorbed dose was estimated after Monte Carlo simulation of proton and ion beam irradiation on metal-oxide and metal-nonmetal memristors. A memristive device comprises two electrodes, each of a nanoscale width, and a double-layer active region disposed between and in electrical contact with electrodes. Following materials were considered for the active region: titanium dioxide, zirconium dioxide, hafnium dioxide, strontium titanium trioxide and galium nitride. Obtained results show that significant amount of oxygen ion - oxygen and nonmetal ion - nonmetal vacancy pairs is to be generated. The loss of such vacancies from the device is believed to deteriorate the device performance over time. Estimated absorbed dose values in the memristor for different constituting materials are of the same order of magnitude because of the close values of treshold displacement energies for the investigated materials.