9 research outputs found
Oxygen Behavior Around Heavily Doped Ultra-Shallow Junction in Si
The diffusion and gettering of oxygen are investigated after low-energy arsenic implantation and furnace
annealing of SiO2/Si structures. Secondary ion mass spectrometry was used for examination of arsenic
and oxygen depth profiles. It is shown that arsenic-doped ultra-shallow junction in Si stimulates the
background oxygen gettering by SiO2/Si interface at the annealing temperatures higher than 850 C.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3516
Effect of the structure of polarimeter characteristic matrix on light polarization measurements
In the paper, we carried out the comparative analysis of three polarimeters
among the most usable their variants: (i) Stokes polarimeter based on phenomenological
definition of Stokes parameters; (ii) Stokes polarimeter based on the method of four
intensities; (iii) Stokes dynamic polarimeter. We show that, since the accuracy in
determination of individual Stokes parameter is different for different types of
polarimeters, and, therewith, it depends on polarization of input light. All that strongly
motivates the choice of type of polarimeter to provide minimum errors in determination
of polarization parameters (ellipticity angle ε, azimuth β, and degree of polarization P)
Testing the optical methods by using the multi-level holographic grating
In this work the interaction peculiarities of electro-magnetic optical range
radiation with gratings’ surfaces are investigated. The multilevel diffractive holographic
grating is proposed to be used for the polarization optical methods testing. This object
allowed to obtain simultaneous visualization of different spatial frequencies and to
estimate both structure and surface peculiarities when working with 3D-objects. Using
this additional information one can remove uncertainty in solution of the inverse problem
of ellipsometry related with ellipsometric angles periodicity. Thereby, multiangle
ellipsometry allowing investigation of the specular reflection component could be used to
study submicron peculiarities of the object. We have also presented the basic aspects of
ellipsometric method optimization. It was shown that anisotropy parameters, such as
linear amplitude anisotropy and linear phase anisotropy, obtained from ellipsometric
measurements are the most effective to ascertain the submicron characteristic dimension
of material
Mechanism of Oxygen Redistribution During Ultra-shallow Junction Formation in Silicon
The transport of dissolved oxygen in the Czochralski silicon towards the arsenic-doped ultra-shallow junction was investigated. Ultra-shallow junction was formed by low-energy As+ ion implantation with the subsequent furnace annealing at 750 C-950 C temperatures for the dopant activation. Oxygen and arse-nic redistributions were investigated by secondary ion mass spectrometry (SIMS) technique. The peculiari-ties of defect creation and transformation were studied by the X-ray diffuse scattering technique (XDS). It was found that oxygen concentration in the arsenic redistribution region is increased a few times already after 1 minute of annealing. Increase of annealing time leads to decrease of oxygen accumulation as a re-sult of oxygen transportation to the SiO2/Si interface. As a result the thickness of screen silicon oxide is in-creased by 0.5 nm. This effect is related with the oxygen gettering from the wafer bulk. A physical mecha-nism of the oxygen transfer is discussed.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3527
Light-induced mass transport in amorphous chalcogenides/gold nanoparticles composites
We have established that mass-transport processes in two types of amorphous
materials, based on light-sensitive inorganic compounds like Se and As₂₀Se₈₀ chalcogenide
glasses (ChG), can be enhanced at the nanoscale in the presence of localized plasmonic
fields generated by visible light in gold nanoparticles (GNPs), if the condition of surface
plasmon resonance (SPR) is fulfilled. It was found that irradiation by light in the presence of
SPR produces profound surface nanostructurizations, and variation in topography follows
closely and permanently the underlying near field intensity pattern. We have proposed a
model of mass-transport in which the existence of moving anisotropic dipolar units and
internal electric field in ChG as a main driving force of this movement is suggested
Formation of silicon nanoclusters in buried ultra-thin oxide layers
The peculiarities of buried layer formation obtained by co-implantation of O2
ions with the energy of 130 keV and carbon ions within the energy range of 30-50 keV
have been investigated. The corresponding ion doses for carbon and oxygen ions were
equal to 2 x 10¹⁶ cm⁻² and 1.8 x 10¹⁷ cm⁻², respectively. It has been observed that annealing at 1150 °C results in enhanced oxygen diffusion towards the region with a maximum carbon concentration. Analysis of X-ray diffraction patterns with a SIMS depth profiles inherent to annealed samples suggests formation of Si nanoclusters in the region with maximum concentrations of carbon and oxygen vacancies. The intensive luminescence has been observed with the maximum at 600 nm, which could be associated with silicon nano-inclusions in thin stoichiometric SiO₂ layer
Growth of silicon self-assembled nanowires by using gold-enhanced CVD technology
In spite of the fact that, a great deal of experimental research has been published, there is a lack of good understanding of silicon nanowires growth to exert control over important properties of the system, though it presents the simplest system like gold on silicon substrate. In the current research, to find the best conditions to grow silicon nanowires with prespecified properties, we studied various technological regimes both of growth-seed formation and conditions of silicon nanowires growth
Influence of deposition rate and substrate temperature on structure and optical features of NiO thin film
Nickel oxide thin films were prepared by direct-current magnetron sputtering method at different deposition rates on unheated and heated substrates. It was shown that the deposited films are the dense arrays of nanowhiskers with the rhombohedral crystalline structure for the unheated substrate and with the face centered cubic structure for the heated substrate. Surface morphology of films consists of nanocrystalline randomly oriented grains. Increasing of the deposition rate and/or the substrate temperature lead to decrease of the film porosity and enlarge of nanocrystals. The maximum oxidation state of the deposited films is observed near the surface
Photoluminescence spectra of nanocrystalline ZnO films obtained by magnetron deposition technique
In this article, the influence of the duration of high-temperature (T = 800 °C) annealing on the transformation of the defective structure and the morphology of thin films from arrays of ZnO nanocrystals synthesized by high-frequency magnetron sputtering was studied using the methods of photoluminescence and atomic force microscopy. On the basis of atomic force microscopy measurements, it was established that ZnO films consist of densely packed grains ranging in size from 40.5 to 49.1 nm. An increase in grain size to statistically significant values over 80 nm is observed as a result of annealing for 60 min. The influence of the high-temperature annealing duration on the transformation of PL spectra of exciton and defects bands and, accordingly, the defect structure of the nanocrystalline ZnO films was determined. In the PL spectra of ZnO nanocrystals, the lines of bound excitons (378 nm, 388 nm) are clearly distinguished in the ultraviolet region. In the visible region, the weak band at 468 nm and fairly intense bands at 559 nm and 683 nm appear, which are characteristic for nanostructured ZnO films obtained by magnetron sputtering. The nature of the specified PL bands is discussed. Differences in the dependence of the intensity of individual PL bands on the duration of annealing are explained by the competition of the recombination mechanisms on non-radiative (Zni) and radiative (OZn, VZn–VO, VZn–2VO) defect centers