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Low-energy nuclear reactions are known to be extremely dependent on the local crystal structure and crystal defects of the deuterated samples. This has a strong influence on both hydrogen diffusion and the effective electron mass. The latter determines the strength of the local electron-screening effect and can change the deuteron–deuteron reaction rates at very low energies by many orders of magnitude. In the present study, zirconium samples were exposed to various conditions and energies of deuteron beams using the unique accelerator system with ultra-high vacuum, installed in the eLBRUS laboratory at the University of Szczecin. Irradiated and virgin samples were investigated by means of the X-ray diffraction (XRD) and positron annihilation spectroscopy (PAS). While the first method delivers information about changes of crystal lattice parameters and possible production of hydrides accompanying the formation of dislocations that are produced during irradiation of the samples, the second one can determine the depth distribution of crystal defects, being especially sensitive to vacancies. The studied Zr samples were also implanted by carbon and oxygen ions in order to simulate the real situation taking place in nuclear reaction experiments and to investigate their influence on the kinetic of produced vacancies. The observed enhancement of the electron-screening effect in the deuteron fusion reaction at very low energies could be explained by formation of a high number of vacancies during the deuteron irradiation of samples. Possible carbon and oxygen impurities can affect this process in various ways by changing the depth distribution of vacancies and their diffusion, but they play only a minor role in the strength of the electron-screening effect. [ABSTRACT FROM AUTHOR]

Herein the manuscript reports kinetics and Thermoluminescence (TL) glow curve analysis of UV-, β- and γ-irradiated natural limestone samples collected from Chunkatta mines of Chhattisgarh basin. The collected samples were annealed at 100°C for 1 h for preheat treatment before irradiation after that the samples were irradiated by UV, β and γ, respectively. After irradiation the 1 mg weigh samples perform for TL glow curve analysis. Collected limestone was characterized by X-ray diffraction analysis technique and crystallite size was calculated using Scherer’s formula. UV-irradiated sample shows the high-temperature peak centered at 250°C, for β-irradiated sample showed well resolved broad TL glow curve at 404 K which is fitted using computerized glow curve deconvolution (CGCD) technique. Similarly, for γ-irradiation the well resolved three distinct peaks at 209, 288 and 388°C showed the formation of deep trapping for γ-irradiation. Dose rate effect for UV- and γ-irradiation reported in details as well as the trap formation were described by trap depth model. Kinetic parameters for UV-, β- and γ-irradiation were calculated using peak shape method by CGCD technique. The study was determined the trap level formation and application related to TL dose response in collected limestone sample. [ABSTRACT FROM PUBLISHER]

This paper reports on the thermoluminescence (TL) properties of Eu doped in two different host matrix phosphors (YO and YBO). The phosphors were prepared by a high temperature solid state reaction method. The method is suitable for a large scale production. The samples were characterized by X-ray diffraction and Rietveld refinement. The different concentration of Eu samples were also examined by TL glow curve analysis for UV, β and γ irradiation. The YO samples showed well resolved broad peaks that covered the temperature range from 50 to 350 °C and the peak temperature was found at 157 °C for the γ irradiation. For the UV irradiated samples a well resolved peak at 121 °C was found for the YO:Eu doped phosphors. The β irradiated samples showed a resolved peak at 182 °C. A different behaviour was observed for the YBO:Eu doped phosphors which showed both higher temperature peaks and lower temperature peaks for UV, β and γ irradiation. Here UV irradiated sample showed the formation of shallow trap (surface trapping) and the γ irradiated sample showed the formation of deep trapping. The estimation of the trap formation was evaluated by the calculation of the trapping parameters. The trapping parameters such as activation energy, order of kinetics and frequency factor were calculated by the peak shape method using the computerized glow curve deconvolution technique. Here most of the peak showed second order of kinetics. The effect of γ, β and UV dose exposure on the TL studies was also examined and it showed a linear response with dose which indicated that the samples might be useful for TL dosimetry. The possible mechanics and information about traps formation are presented in detail. [ABSTRACT FROM AUTHOR]

Abstract: The effects of 70MeV irradiation of iron ions in p-type silicon at fluences between 1×1012 and 5×1014 ionscm−2 were investigated by high resolution X-ray diffraction (HRXRD), electron spin resonance (ESR) and current–voltage measurements. The irradiated samples were isochronally annealed in nitrogen ambient up to 973K for 2min using the rapid thermal annealing (RTA) system. The screw dislocation density of the annealed sample (5×1014 ionscm−2) estimated at each stage of annealing from the broadening of the HRXRD peak was observed to change from 8.70×107 to 1.58×107 cm−2 with increasing temperatures. The strain and stress parameters estimated at each stage of annealing using the FWHM of ω-scan clearly indicate relative trend towards the un-irradiated silicon sample. The electron spin resonance studies indicate the presence of the dangling bond state of silicon (Siomplex defects. The annealing at 873K was found to be sufficient for complete removal of the defect centers induced due to irradiation. The I–V studies performed on the irradiated samples before and after annealing indicate that the defects created as a consequence of irradiation trap the charge carriers. [Copyright &y& Elsevier]

Abstract: The synthesis of buried silicon nitride insulating layers was carried out by SIMNI (separation by implanted nitrogen) process using implantation of 140 keV nitrogen (14N+) ions at fluence of 5.0×1017 cm−2 at room temperature with current density of 45–46 µA-cm−2 into <111> single crystal silicon substrates. To study the swift heavy ion (SHI) induced recrystallization of SOI (Silicon-on-insulator) structures, the implanted samples were irradiated with 60 MeV Ni+5 ions with fluence of 1.0×1014 cm−2 at high temperature (270 °C). The Micro-Raman spectra show distinct peaks assigned to transverse acoustical (TA) and transverse optical (TO) vibration bands of amorphous silicon. The HRXRD studies show that the full width at half maximum (FWHM) of irradiated samples increases with respect to virgin silicon and the samples remain amorphous even after SHI irradiation. [Copyright &y& Elsevier]

The Al-induced crystallization of amorphous (a) -Si under thermal annealing and swift heavy ion irradiation has been investigated. The c -Al (50 nm)/ a -Si (150 nm) thin films have been prepared on thermally oxidized Si-substrates. A set of samples have been annealed at temperatures ranging from 100 °C to 500 °C to achieve crystallization. Another set of similar samples have been irradiated at an elevated temperature of 100 °C using 100 MeV Ni+7 ions at fluences of 1 × 1012 ions-cm−2, 5 × 1012 ions-cm−2, 1 × 1013 ions-cm−2, and 5 × 1013 ions-cm−2. The crystallization of a -Si is observed at annealing temperature of 200 °C. The crystallinity increases with increasing temperature. On the other hand, irradiation using swift heavy ion leads to crystallization of a -Si at significantly lower temperature of 100 °C. The irradiation induced crystallization is explained in terms of creation of vacancies, interstitials and mixing of Si and Al atoms at a -Si/ c -metal interface due to energy deposited by swift Ni ions. • The Al induced crystallization of a -Si under thermal annealing as well as under swift heavy ion irradiation are presented. • The crystallization of a -Si starts at annealing temperature of 200 °C and crystallinity increases with increasing temperature. • Irradiation process using swift heavy ion leads to crystallization of a -Si at significantly lower temperature of 100 °C. • Irradiation induced crystallization is explained in terms of creation of vacancies, interstitials and mixing of Si and Al atoms. • Crystallization of a-Si using SHI irradiation process is possible at very low temperature without heating whole substrate. [ABSTRACT FROM AUTHOR]

• Growth of orientation control low resistive nickel mono-silicide (NiSi) phase. • NiSi phase formation at room temperature under low energy ion irradiation. • The effect of Ni film thickness on NiSi phase formation and electrical properties. • Better crystalline phase is observed for higher Ni film thickness than lower one. • Most of the crystallites are oriented in (103) plane. Nickel mono-silicide (NiSi) is considered as a promising material for developing low resistance contacts in complementary metal-oxide-semiconductor technology. In the present work, we report the effect of Ni film thickness on orientation control of low resistive Nickel mono-silicide (NiSi) phase formation using low energy ion irradiation at room temperature. In order to study the effect of Ni film thickness on NiSi phase formation, the Ni films of thicknesses 30 nm and 60 nm were deposited on Si (111) substrate using thermal evaporation technique in a high vacuum chamber. The as prepared Ni/Si samples were then irradiated via 120 keV Si ions with different fluences of 7 × 1014, 1 × 1015, 3 × 1015 and 7 × 1015 ions-cm−2 at room temperature. The x-ray diffraction and transmission electron microscopy measurements clearly confirm the formation of mono-silicide phase. The composition of the NiSi phase is determined by Rutherford backscattering spectrometry measurements. The crystallinity of NiSi phase has been observed to be better for 60 nm Ni film as compared to the 30 nm Ni film on Si substrate. Most of the NiSi crystallites are found to be oriented in (103) lattice plane. The resistivity and sheet resistance of the NiSi/Si films are found to be very low. The role of composition of Ni and Si in NiSi phase on resistivity and sheet resistance of the films has been investigated carefully. The detailed mechanisms behind the above observations have been discussed in the paper. [ABSTRACT FROM AUTHOR]