Applying the in situ X-ray reflectometry method to define the nanodimensional silicon film parameters
The monitoring methods for measuring the film structure parameters in formation process, namely, the in situ methods, are currently of special significance. Their application provides obtaining the films with the given characteristics, which results in a fast correction of the technological modes. The possibilities of the in situ method of the X-ray reflectometry for defining the parameters of the nanodimensional films during their formation are discussed. The results are given of testing the magnetron deposition of the silicon films and other materials on the silicon substrate.
Method of in-situ X-ray reflectivity is presented. The results of investigation of titanium and silicon thin films in real-time of their deposition on silicon substrates are discussed.
Dependences of the etch rates for KOH and HF:H2O2:CH3COOH solutions on SiGe layer composition were investigated. The obtained results has been proposed to use for formation of the submicron relief on the silicon surface via selective etching of the structures with Ge(Si) self-assembled nanoislands. In the framework of the proposed approach the Ge(Si) nanoislands serve as a mask for selective etching of Si in a mixture of an aqueous solution of KOH with isopropyl alcohol, followed by the islands removal from the surface by the selective etching in HF:H2O2:CH3COOH. It was demonstrated experimentally that such approach allows to produce the submicron relief on a silicon surface, which leads to the significant decrease of the reflectivity in a wide spectral range. It is believed that the proposed method of surface relief formation can be used to improve the efficiency of the thin-film solar cells based on the crystalline silicon.
Silicon single crystals were studied by X-ray topo-tomography using laboratory sources. Experimental set up is described. Three-dimensional distribution of defect regions in the crystal were obtained.
At present particular attention is given to techniques which allow the monitoring of single layer and multilayer thin film materials directly during their formation - in-situ methods. Application of these methods helps to ensure a film with desired characteristics, allowing quickly adjust process conditions. The paper describes the possibilities of the in-situ X-ray reflectivity to determine the parameters of nanoscale films in real time of their formation. Experimental results on the magnetron deposition of nanoscale Si films and other materials on silicon substrates are presented.
The formation and properties of locally tensile strained Ge microstructures (“microbridges”) based on Ge layers grown on silicon substrates are investigated. The elastic-strain distribution in suspended Ge microbridges is analyzed theoretically. This analysis indicates that, in order to attain the maximum tensile strain within a microbridge, the accumulation of strain in all corners of the fabricated microstructure has to be minimized. Measurements of the local strain using Raman scattering show significant enhancement of the tensile strain from 0.2–0.25% in the initial Ge film to ~2.4% in the Ge microbridges. A considerable increase in the luminescence intensity and significant modification of its spectrum in the regions of maximum tensile strain in Ge microbridges and in their vicinity as compared to weakly strained regions of the initial Ge film is demonstrated by microphotoluminescence spectroscopy.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.