Persons

The conventional metal connections cease to meet the growing demands of the quality of information transmission, speed and noise immunity. This is especially acute in the inter-core connections of ultra-large scale integrated circuits. One of the promising methods in solving this problem is using the integrated optical switching systems on the bases of the injection lasers with functionally integrated optical radiation modulators. The injection lasers enable the modulation of laser radiation by subpicosecond control pulses at the time-constant pump current and realization of sources and modulators of optical radiation in a single AB nanoheterostructure with heterojunctions of the second type. In this study the transport of the charge carriers in a functionally integrated laser modulator with internal frequency modulation of the generated optical radiation using the proposed two-dimensional diffusion-drift model and the numerical simulation technique has been studied. The results of numerical modeling of the charge carriers transport processes in a laser modulator have been obtained when the pump current is switched on and the control voltage is pulsed. The results of numerical simulation of the transient processes take into account the structural features, transport effects, the mechanisms of simulated and spontaneous radiative recombination, and the lifetime of photons. It has been shown that the maximum modulation frequency of laser modulation is determined by the subpicosecond time of the controlled spatial relocation of the charge carrier density maximums in the quantum wells of the laser modulator and the photon lifetime in a resonant cavity and corresponds to the terahertz range. To increase the maximum modulation frequency, it is necessary to decrease the photon lifetime in the active region of the laser-modulator to values less than 3 ps. The proposed model and numerical modeling technique allow the optimization of the parameters of the functionally integrated laser-modulator and providing the required values of the maximum modulation frequency of optical radiation, the modulation factor and the threshold pump current density.

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Some peculiarities of the controlled rearrangement of charge carriers in the nanostructures based on the tunnel-connected quantum regions, formed by GaAs/AlGaAs heterojunctions, have been considered. The results of numerical modeling of the wave function rearrangement dynamics have been discussed.

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The experimental study results of modification of the probes for Critical Dimension Atomic Force Microscopy (CD-AFM) by deposition of carbon nanotubes (CNT) have been presented. This permits to improve the accuracy of determining the roughness of the submicron structures vertical walls surface. The deposition methods of individual CNT on the tip of the AFM probe, based on mechanical and electrostatic interactions between the probe and an array of the vertically aligned carbon nanotubes (VACNT), have been studied. It has been shown that when the distance between the AFM tip and an array VACNT is 1 nm and the applied voltage is in the range of 20-30 V, an individual carbon nanotube is deposited on the tip. On the basis of the obtained results a probe with the carbon nanotube on the tip (CNT probe) with the 7nm radius and an aspect ratio 1:15 the probe has been formed. The CNT probe studies have demonstrated that its use improves the resolution and accuracy of the AFM measurements as compared to the commercial probe, and, also, allows determining the roughness of the vertical walls of the high aspect structures by CD-AFM. The results obtained can be used to develop the manufacturing processes and to repair special probes for AFM, including the probes for CD-AFM, as well as to develop the techniques and the inter-operation diagnostics of the process parameters in manufacturing the elements of micro-and nanoelectronics, micro- and nanosystem structures.

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The results of experimental studies on the activation nanolithography modes of a thin titan film by local anode oxidation (LAO) have been presented. It has been determined that the use of UV-stimulation leads to reduction of the oxide nanosized structures (ONS) geometrical sizes and is accompanied by an increase of the amplitude from 6 to 7 V and the impulses duration from 50 to 100 ms of the threshold voltage at relative humidity of 50%. The results of experimental studies on the influence of the cantilever conducting covering material and the substrate temperatures on the formed ONS geometrical sizes have been presented.

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The results of experimental studies of modes of ion beam included deposition of Pt with thickness from (0.48 ± 0.1) to (17.38 ± 0.1) nm by focused ion beams have been represented. The experimentally determined rate of ion-induced deposition of Pt, which, depending on process parameters of the focused ion beam is changed from (0.28 ± 0.02) to (6.7 ± 0.5) nm/s. It has been found that the deviation of the lateral dimensions of Pt nanostructures from the designed pattern decreases from (29.3 ± 0.07) % to (2.4 ± 0.2) % for the various modes of deposition time. It has been shown that at the thicknesses of Pt nanostructures over 3 nm their resistivity is (23.4 ± 1.8) Om∙cm and weakly depends on the thickness of the structure. The results can be used to develop processes of formation of nanostructures for microelectronics, nano- and microsystems technology on the basis of the focused ion beams method.

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