Simulation of Radiation Effects in SiO2/Si Structures

We describe space-time evolution of electric charge induced in dielectric layer of simulated metal-insulator-semiconductor structures due to irradiation with X-rays. The system of equations used as a basis of the simulation model is solved iteratively by efficient numerical method. The obtained simulation results correlate well with the respective data presented in other scientific publications

Ion Guiding in Alumina Nanocapillaries

The 150 keV proton beams transmission through nanocapillary structures of Al2O3 was studied. The dependence of count rate of transmitted particles on tilt angle and the angular distribution of transmitted beams were measured. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3513

Influence of Impact Ionization Process on Current-Voltage Characteristics of Nanoscale Silicon n-Channel MOSFET

The current-voltage characteristics of nanoscale silicon n-channel MOSFET with 50 nm channel length are calculated in the present study. Both the electron and hole transport are simulated by means of the en-semble Monte Carlo method. The importance of electron impact ionization process in the transistor chan-nel for drain biases higher than 1 V is shown. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3537

Simulation of Radiation Effects in SiO2/Si Structures

We describe space-time evolution of electric charge induced in dielectric layer of simulated metal-insulator-semiconductor structures due to irradiation with X-rays. The system of equations used as a basis of the simulation model is solved iteratively by efficient numerical method. The obtained simulation results correlate well with the respective data presented in other scientific publications

The Comparative Investigations of Structural and Optical Properties of GaSb nanocrystals / Si layers

Optical and structural properties of GaSb nanocrystals fabricated by co-implantation of Ga and Sb ions in single crystalline Si (100), followed by thermal treatment are investigated. In the first group of samples named Si / GaSb the implantation of Ga ions was followed by Sb implantation, whereas in the second group of samples named Si / SbGa with increased by factor 1.4 ion fluence the order of implantation was inverted. The presence of nanocrystals in both kinds of samples was proved by TEM and RS experiments. Low-temperature PL measurements show a PL broad band in the region at 0.75-1.1 eV for Si / SbGa samples annealed at 900 °C. No PL was observed in the Si/SbGa samples after annealing at 1100 °C. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3516

Effects of annealing regims on the structural and optical properties of inas and gasb nanocryctals created by ion-beam synthesis in Si matrix

We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implantation of (As+In) and (Ga+Sb) ions followed a thermal annealing. In order to characterize the implanted samples Rutherford backscattering spectrometry in combination with the channelling (RBS/C), transmission electron microscopy (TEM), Raman spectrometry (RS) and low-temperature photoluminescence (PL) techniques were employed. It was demonstrated that by introducing getter, varying the ion implantation temperature, ion fluences and post-implantation annealing duration and temperature it is possible to form InAs and GaSb nanocrystals in the range of sizes of (2 – 80) nm and create different types of secondary defects distribution. RS results confirm the crystalline state of the clusters in the silicon matrix after high-fluence implantation of heavy (As+In) and (Ga+Sb) ions. Significant redistribution of implanted species has been revealed after “hot” implantation and post-implantation annealing. We have suggested that it is caused by non-equilibrium diffusion. A broad band in the spectral region of 0.7 – 1.1 eV is detected in the photoluminescence spectra of the samples. The nature of this PL band is discussed.We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implantation of (As+In) and (Ga+Sb) ions followed a thermal annealing. In order to characterize the implanted samples Rutherford backscattering spectrometry in combination with the channelling (RBS/C), transmission electron microscopy (TEM), Raman spectrometry (RS) and low-temperature photoluminescence (PL) techniques were employed. It was demonstrated that by introducing getter, varying the ion implantation temperature, ion fluences and post-implantation annealing duration and temperature it is possible to form InAs and GaSb nanocrystals in the range of sizes of (2 – 80) nm and create different types of secondary defects distribution. RS results confirm the crystalline state of the clusters in the silicon matrix after high-fluence implantation of heavy (As+In) and (Ga+Sb) ions. Significant redistribution of implanted species has been revealed after “hot” implantation and post-implantation annealing. We have suggested that it is caused by non-equilibrium diffusion. A broad band in the spectral region of 0.7 – 1.1 eV is detected in the photoluminescence spectra of the samples. The nature of this PL band is discussed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2083

Radiation Resistance of high-entropy nanostructured (Ti, Hf, Zr, V, Nb)N coatings

The influence of high-fluence ion irradiation of nanostructured (Ti, Hf, Zr, V, Nb)N coatings is revealed for the first time. The energy of irradiating helium ions is equal to 500 keV, and their fluence falls into the interval 5 × 1016–3 × 1017 ions/cm2 . The performance of the coatings in a nuclear reactor is simulated by conducting post-irradiation thermal annealing at 773 K for 15 min. The elemental composition, structure, morphology, and strength properties of the (Ti, Hf, Zr, V, Nb)N coatings are studied before and after irradiation. No considerable structural and phase modifications in the coatings are found after irradiation, except for the fact that crystallites in the coatings drastically reduce in size to less than 10 nm. Nor does the atomic composition of the coatings change. It is shown that the microhardness of the coatings depends on the fluence of irradiating ions nonlinearly. It can be argued that the (Ti, Hf, Zr, V, Nb)N coatings are radiationresistant and hence promising for claddings of fuel elements in nuclear reactors

Radiation Resistance of high-entropy nanostructured (Ti, Hf, Zr, V, Nb)N coatings

The influence of high-fluence ion irradiation of nanostructured (Ti, Hf, Zr, V, Nb)N coatings is revealed for the first time. The energy of irradiating helium ions is equal to 500 keV, and their fluence falls into the interval 5 × 1016–3 × 1017 ions/cm2 . The performance of the coatings in a nuclear reactor is simulated by conducting post-irradiation thermal annealing at 773 K for 15 min. The elemental composition, structure, morphology, and strength properties of the (Ti, Hf, Zr, V, Nb)N coatings are studied before and after irradiation. No considerable structural and phase modifications in the coatings are found after irradiation, except for the fact that crystallites in the coatings drastically reduce in size to less than 10 nm. Nor does the atomic composition of the coatings change. It is shown that the microhardness of the coatings depends on the fluence of irradiating ions nonlinearly. It can be argued that the (Ti, Hf, Zr, V, Nb)N coatings are radiationresistant and hence promising for claddings of fuel elements in nuclear reactors

Phase Transformation in the Annealed Si-Rich SiNx Films Studied by Raman Scattering

The Si-rich SiNx films were deposited on Si wafers by low pressure chemical vapor deposition (LPCVD) technique followed by annealing at (800 – 1200) °C. Excess (overstoichiometric) Si content in nitride films was calculated from Rutherford backscattering data (RBS). Existence and evolution of Si nanoclusters from amorphous to crystalline ones under high temperature treatment were confirmed by Raman scattering (RS) measurements. Amorphous Si clusters have already existed in as-deposited SiNx films. Thermal treatment results in the formation of additional amorphous nanoclusters and in their crystallization with anneal temperature increasing. Nitride films annealed at 1200 °C contain crystalline Si clusters only. It was revealed a dependence of Si wafer’s Raman scattering intensity on the temperature of SiNx/Si structures annealing. This information in combination with RBS data has allowed us to estimate and distinguish the excess silicon aggregated in clusters and the excess silicon distributed over the silicon nitride matrix

Formation and Characterization of Nanostructured Composite Coatings Based on the TiN Phase

Nanostructured thin-film coatings based on titanium nitride, doped with silicon, chromium and aluminium were the object of this study. The creation of a smooth transition layer was carried out by the changing of a supplying nitrogen ow to the vacuum chamber during the application. TiSiN, TiCrN and TiAlN coatings were deposited. The studies of the structure, elemental and phase composition of the coatings were carried out. Also, the performance of coatings was investigated. The results can be used in today's technology, such as mechanical engineering