M. S. Solodovnik

Development of New Metamaterials for Advanced Element Base of Micro- and Nanoelectronics, and Microsystem Devices

The results of experimental researches of the geometrical parameters of vertically aligned carbon nanotubes (VACNTs) are present by atomic force microscopy. The analysis of the applicability of the different AFM modes to determine the geometrical parameters of VACNTs array was carried out and based on this analysis the rapid-technique for determination of the length of the nanotubes in VACNTs array was developed. Unified two-layer polysilicon surface micromachining process for manufacture of biaxial micromechanical gyroscope , triaxial micromechanical accelerometer and biaxial nanomechanical accelerometer was proposed. Polysilicon inertial masses were fabricated by optical lithography, dry etching under different masks and wet etching of sacrificial layer. We developed AFM-technique for determination of electrical parameters GaAs nanowires (NWs) , which does not require additional operations of NW fixation and allows one to estimate the resistivity and conductivity type of NW material. The obtained results can use to develop of the nanodiagnostic methods and the processes of formation of micro- and nanoelectronic elements based.

A study of the formation modes of nanosized oxide structures of gallium arsenide by local anodic oxidation

Results obtained in a study of the influence exerted by the technological modes of local anodic oxidation (LAO) on the process in which nanosized oxide structures (NOSs) are formed on the surface of gallium arsenide are reported. The effect of the amplitude and duration of voltage pulses applied to the probesubstrate system, relative air humidity in the technological chamber, and amplitude of cantilever oscillations on the geometric parameters of gallium arsenide NOSs has been examined. It was found that raising the relative humidity from 60 to 90% results in a decrease in the threshold LAO voltage from 7.0 to 6.0 V. It is shown that raising the oscillation amplitude from 0.1 to 2.8 nm leads to a decrease in the NOS height from 3.20 ± 0.34 to 1.10 ± 0.13 nm and in the NOS diameter from 218.4 ± 29.5 to 78.1 ± 10.3 nm.

Effect of interaction in the Ga–As–O system on the morphology of a GaAs surface during molecular-beam epitaxy

A thermodynamic analysis of processes of interphase interaction in the Ga–As–O system has been performed and their theoretical laws have been determined, taking into account nonlinear thermal physical properties of the compounds, the oxide film compositions, and modes of molecular-beam epitaxy of GaAs. The processes of interaction of the native oxide of GaAs with the substrate material and also with Ga and As4 from a vapor gaseous phase have been studied experimentally. The experimental results correlate with the results of the thermodynamic analysis. The laws of influence of the removal of the proper oxide on the evolution of the GaAs surface morphology under conditions of the molecular-beam epitaxy have been proposed.

The study of influence of the gas flow rate to etched layer thickness, and roughness of the anisotropy field of gallium arsenide is etched in the plasma chemical etching process

In the experiments on the etched surface of gallium arsenide were performed. We studied the effect of BCl3 gas flow rate on the thickness of the etched layer. GaAs etching rate was: 537,4 nm/min 28,7 nm/min 2,6 nm/min, the values of the flow rate of BCl3 NBCl3 - 15, 10, 5 cc/min, respectively. The effect of BCl3 gas flow rate to the mean-square roughness of the etched surface. The influence of the anisotropy of the process on the geometry of the etched area. Revealed that the deflection angle for the samples treated with the working gas flow rate NBCl3 - 15 cc/min in the [110] direction was α [110] = 65,5° in direction [111] was α [111] = 45,58°. For samples treated with the working gas flow rate NBCl3 - 10 cc/min in the [110] direction was α [110] = 20,94° in direction [111] was α [111] = 11,37°. For samples treated with the working gas flow rate NBCl3 - 5 cc/min in the [110] was α [110] = 0,32° in direction [111] was α [111] = 0,21°. The results can be used to produce discrete diodes, heterojunction devices, and other results.

Studying the modes of nanodimensional surface profiling of Gallium Arsenide epitaxial structures by local anodic oxidation

In this work we present the results of studying the influence of the local anodic oxidation (LAO) technological modes on the process of formation of oxide nanodimensional structures (ONSs) at the surface of Gallium Arsenide epitaxial structures (ESs). We have studied the influence of the amplitude and duration of pulses of voltage applied to the system probe-substrate and amplitude of cantilever vibrations on the geometric parameters of GaAs ONS. The influence of LAO modes on the geometric parameters of profiled nanodimensional structures (PNSs) obtained at the surface of GaAs ES after etching the ONS formed by LAO has been studied. It is established that an increase in the amplitude and duration of pulses of the applied voltage by LAO results in an increase in the height, depth, and diameter of oxide and profiled nanodimensional structures at the surface of GaAs ES. It is shown that an increase in the amplitude of the cantilever vibrations from 3 to 26 nm results in a decrease in the PNS from 9.1 ± 1.6 to 3.4 ± 0.3 nm and diameter of PNS from 274 ± 34 to 167 ± 29 nm. The results may be used for developing the technological processes for preparing an element base for nanoelectronics based on Gallium Arsenide.

Studying the effect of geometric parameters of oriented GaAs nanowhiskers on Young’s modulus using atomic force microscopy

A technique for determining Young’s modulus of oriented nanowhiskers using atomic force microscopy is developed. Results of studying the effect of geometric parameters on Young’s modulus of oriented gallium arsenide nanowhiskers are presented. Young’s modulus value has been found experimentally for the GaAs nanowhiskers, which varied from 9 to 143 GPa depending on their aspect ratio. It is shown that Young’s modulus of the GaAs nanowhiskers depends on their aspect ratio and can exceed Young’s modulus of the bulk GaAs. The results can be used in the development of technological processes for forming structures of the nano- and microsystem hardware and the nano- and microelectronics based on oriented nanowhiskers, in particular arsenide gallium nanowhiskers, as well as in the development of techniques for the nanodiagnostics of filamentary structures.

Study of the phase composition of nanostructures produced by the local anodic oxidation of titanium films

The results of experimental studies of the phase composition of oxide nanostructures formed by the local anodic oxidation of a titanium thin film are reported. The data of the phase analysis of titanium-oxide nanostructures are obtained by X-ray photoelectron spectroscopy in the ion profiling mode of measurements. It is established that the surface of titanium-oxide nanostructures 4.5 ± 0.2 nm in height possesses a binding energy of core levels characteristic of TiO2 (458.4 eV). By analyzing the titanium-oxide nanostructures in depth by X-ray photoelectron spectroscopy, the formation of phases with binding energies of core levels characteristic of Ti2O3 (456.6 eV) and TiO (454.8 eV) is established. The results can be used in developing the technological processes of the formation of a future electronic-component base for nanoelectronics on the basis of titanium-oxide nanostructures and probe nanotechnologies.

Kinetic Monte Carlo simulation of GaAs(001) MBE growth considering the V/III flux ratio effect

The kinetic Monte Carlo method is used to study the initial stage of GaAs molecular beam epitaxial growth on the GaAs(001) surface via fluxes of Ga atoms and As tetramers. The developed algorithm allows efficient investigation of the effects of the V/III flux ratio upon the geometrical characteristics of islands in the temperature range at which the (2 × 4) reconstruction of GaAs(001) is exclusively observed. The island density increases with an increasing V/III flux ratio, whereas the average island size decreases. The temperature dependences of the island characteristics are observed to be stronger at a smaller V/III flux ratio because large arsenic fluxes compensate the enhanced desorption at high temperatures. The island size distribution is more uniform at small V/III flux ratios, while a higher concentration of small clusters is observed as the arsenic flux increases. The analysis of the island morphology and size distribution function suggests that an increase in the V/III flux ratio and a decrease...

Monte Carlo simulation of V/III flux ratio influence on GaAs island nucleation during MBE

The kinetic Monte Carlo simulation of GaAs/GaAs(001) molecular beam epitaxial growth considering V/III flux ratio influence on nucleating island characteristics is presented. It is shown that the island density increases with the surface coverage increase and reaches saturation after deposition of ~0.1 monolayer of GaAs. The increase of V/III flux ratio from 3 to 40 leads to the increase of the island density from 1.9-1012 to 2.6-1012 cm-2. At the same time the average size decreases from 4.4 to 4.1 nm. The island size distribution function narrows with V/III flux ratio increase. This is attributed to the shortage of gallium atoms in comparison with deposited arsenic molecules that prevents large island formation and leads to the dramatic growth of little island concentration. The simulation demonstrates good agreement with experimental results.

A study of the vertical walls and the surface roughness GaAs after the operation in the combined plasma etching

The paper presents the experimental results of the combination of AFM lithography and plasma chemical etching the surface of the gallium arsenide samples. Results dilution and application modes for AFM lithography photoresist, also shown on the image forming modes photoresist surface. Showing results nanoprofilirovaniya surface. Results regimes plasma chemical etching. The analysis of the etching rate is etched surface roughness was studied by atomic force microscopy. Judged from the vertical deflection angle of the initial structures and photoresist obtained after etching.