A.P. Kobzev

DEPOSITION AND PROPERTIES OF NICKEL OXIDE FILMS PRODUCED BY DC REACTIVE MAGNETRON SPUTTERING

Nickel oxide (NiO) thin films were prepared on Si substrates by DC reactive magnetron sputtering from a nickel metal target in Ar+O2 with the relative O2 content varied from 15 to 50%. The effects of the O2 gas content on the deposition rate, structure, composition and electrical properties were investigated. NiO stoichiometric films were obtained with a polycrystalline structure and a specific resistivity of near 300 Ωcm at 25% O2 content in the discharge gas. Film composition and structure, and this resistivity, were dependent on the discharge parameters. Thus the deposited films had amorphous and polycrystalline structures with Ni\O ratio ranges between 0.71 and 1.02 as a function of the discharge O2 content.

Effect of Fe and Zr ion implantation and high-current electron irradiation treatment on chemical and mechanical properties of Ti–V–Al Alloy

Using Rutherford backscattering spectroscopy, nuclear elastic resonance analysis, atomic force microscopy, transmission electron microscopy, and wear resistance and microhardness tests, the alloy Ti41–V41–Al18 was investigated after Fe ion (60 kV) and Zr (40 kV) ion implantation and subsequent high-current electron beam (HCEB) irradiation at an energy flow density of 6 J/cm2, called duplex treatment. Profiles show that the maximum concentration of Fe ions was 16.5 at. % at 85 nm from sample surface and that of Zr ions was 0.85 at. % at 56 nm. The maximum of the Fe concentration profile was found to shift to the large sample depth toward after increasing the implantation dose. The surface alloy layer is composed of a number of structures: grains of dislocation substructure (2×1010 cm−2), grains with plates, and grains with packed martensite. The disorientation of regions is observed. After HCEB treatment, the disorientation of microregions increases (Δα=7.5°) and particles of Ti2Fe are formed. After double...

Properties of amorphous silicon carbide films prepared by PECVD

Abstract Amorphous SiC was prepared by plasma enhanced chemical vapour deposition of SiH 4 and CH 4 . The properties of the SiC deposits were studied using a combination of infrared (IR), RBS, ERD (electron recoiling detection) and AES measurement. Infra red spectra showed the presence of SiC, SiH and CH bonds. The compositions of the silicon, carbon and hydrogen in the films were found to be dependent on the preparation conditions.

Application of the ERD method for hydrogen determination in silicon (oxy) nitride thin films prepared by ECR plasma deposition

Abstract Elastic recoil detection method was applied for the study of hydrogen in silicon nitride as well as silicon oxynitride thin films. For this purpose 2.4 MeV 4 He + ions produced by the Van de Graaff accelerator of JINR have been used. The thin films have been prepared by the electron cyclotron resonance plasma deposition technique. The physical properties of these layers, which play an important role in the technology of semiconductor devices, are strongly dependent on the amount of hydrogen incorporated during their deposition. The technique of the hydrogen depth determination by ERD is very important for the optimization of process parameters of the ECR plasma deposition of the silicon (oxy)nitride layers with optimal physical and electrical properties.

Study of the d(p, γ)3He reaction at ultralow energies using a zirconium deuteride target

Abstract The mechanism for the d ( p , γ ) 3 He reaction in the region of ultralow proton–deuteron collision energies (6.67 E S -factor and the effective pd reaction cross section on the proton–deuteron collision energy are measured. The results are compared with the available literature data. The results of this work agree with the experimental results obtained by the LUNA collaboration with the target of gaseous deuterium.

Comparison of responses of CR-39, PM-355, and CN track detectors to energetic hydrogen-, helium-, nitrogen-, and oxygen-ions

Abstract Samples made of the CR-39 and PM-355 plastic nuclear track detectors (NTDs) as well as of the CN films were irradiated with quasi-monoenergetic beams of protons, alphas, N + -, and O + -ions produced by various accelerators. For different samples an energy value of the particle beams was changed from several hundreds keV to 3 or 4.5 MeV. After irradiation the detector samples were etched chemically under controlled conditions during periods lasting from 2 hrs to 20 hrs. Every 2 hrs track diameters were measured by means of an optical microscope. Differences in the crater diameters in the detectors etched in steps, and those etched continously, have been found to be smaller than 10 percent. The paper results detailed calibration diagrams showing a dependence of track diameters on the ion energy value for different etching times.

L-subshell ionization by 14N ions

Abstract L-subshell ionization cross sections for selected heavy elements between La and Au were measured for 14N ions in the energy range 1.75–22.4 MeV. The L-X-ray yields were corrected for a substantial projectile energy-loss in the target, being up to 20% for the lowest energies, and the X-ray absorption effect. The measured L-subshell ionization cross sections are compared with the predictions of the ECPSSR theory for direct ionization and electron capture processes and the SCA calculations for direct ionization. Both theories underestimate the data for L2-subshell for the lowest energies. This is attributed to the effect of intra-shell transitions not accounted for in both calculations. Systematic overestimation of measured L3-subshell cross sections by the theories is also found for higher scaled velocities ξ > 0.5, where the binding-polarization effects are expected to play an important role.

Investigation of the elements depth profiles in surface layers of glass modified by ion beam assisted deposition

Abstract Depth profiles of Ti, O, N, C, H, Cu and substrate atoms (Na, Ca, Si and O) were investigated in near-surface layers of glass. Rutherford Backscattering Spectrometry (RBS) of 4He+ ions, non-Rutherford and resonant elastic Backscattering Spectrometry (BS) of 4He+ and 1H+ ions (reactions 16O(p, p)16O, 28Si(p, p)28Si, 12C(p, p)12C, 14N(p, p)14N and 16O(4He, 4He)16O) and method of Elastic Recoil Detection (ERD) of 1H+ using 2.4 MeV 4He+ analysis beam were applied in complex for the elements depth profiling. The sample was modified by using the new ion source TAMEK. The source operated in the regime of ion beam assisted deposition (IBAD) of wide aperture (300 cm2) Ti ions flow (ion implantation at average beam energy ≈ 120 keV and simultaneous deposition of the same ions at energy 100 eV) in pulse mode. The sample preparation was carried out in a nitrogen atmosphere with the pressure of about 3 × 10−4 Torr. Rate of dose accumulation at the grounded target was ≈ 1016 ion cm 2 min. Surface temperature of the sample was less than 50°C during IBAD treatment. Two characteristic areas were indicated in the modified layer: the mutual mixed Ti-glass layer and the coating with Ti, O, N, C, H and Cu composition. Total thickness of modified Ti-glass layer was found to be ≈ 400 nm.

Preparation of hydrogenated amorphous silicon carbide thin films by plasma enhanced chemical vapour deposition

Thin silicon carbide (SiC) films were prepared by plasma enhanced chemical vapour deposition (PECVD). The structural properties of SiC films were investigated by IR, RBS, and ERD measurement techniques. The results showed that the films contain the typical features found in hydrogenated amorphous SiC. The I-U measurements were used to electrical characterization of Au Schottky contacts prepared on SiC surfaces.

RBS study of amorphous silicon carbide films deposited by PECVD

We present properties of nitrogen-doped amorphous silicon carbide films that were grown by a plasma enhanced chemical vapour deposition (PECVD) technique and annealed by pulsed electron beam. Samples with different amounts of N were achieved by a small addition of ammonia NH3 into the gas mixture of silane SiH4 and methane CH4, which were directly introduced into the reaction chamber. The actual amount of nitrogen in the SiC films was determined by Rutherford backscattering spectrometry (RBS). A simulation of the RBS spectra was used to calculate the concentration of carbon, silicon and nitrogen.