Two diamond Schottky diodes in pseudo-vertical geometry, "power" and "sensor", fabricated on a single chip and a dependence of their characteristics on temperature was studied. The temperature sensitivity of the diode-sensor in the range 2,4-3 mV/degrees C was determined. For the first time, the possibility of a real-time temperature measurement of a power Schottky diode using integrated sensor-diode has been demonstrated. The temperature dynamics of a power diode in case of self-heating during current pulses was investigated. Diodes have an ideality factor close to unity and a high uniformity of the Schottky barrier height. A current density of 720 A/cm2 at a temperature of 210 degrees C has been achieved for the power diode. The breakdown voltage was about 300 V, which corresponds to an electric field strength of 2.5 MV/cm.

The influence of methane plasma parameters on the deposition rate and on the content of the hydrogen and the sp3-carbon fraction in hydrogenated diamond-like carbon films (DLC) was investigated. It was shown that the proportion of the sp3-carbon fraction mainly depends on the inductive power and the argon addition to the plasma; the latter also contributes to a decrease of hydrogen in the films.

Dispersions of graphene oxide and its reduced form have been obtained and characterized by UV spectroscopy. Features of reduction of graphene oxide in the composition of coatings deposited onto solid substrates (aluminum, optical glass, and KDP single crystal) by interaction with different reducing agents (hydrazine hydrate, formalin, ascorbic and citric acids, and ammonium citrate) have been studied. Surface structures have been examined by Raman spectroscopy. The surface morphology of the coatings and defectiveness of the graphene-like materials obtained by reduction of the graphene oxide dispersions on the substrate surface have been investigated.

In this work, the elemental composition and the concentration distribution of silicon dopant over the thickness of the grown GaAs epitaxial layer in narrow grooves formed by etching in chlorpentafluoroethane plasma were studied.

In this work the features of organometallic gas-phase epitaxy of gallium arsenide in grooves obtained by etching in plasma of chlorpetafluoroethane were studied. It was shown that the epitaxial overgrowth depends on grooves location relative to the base cut of the substrate.

The study of the electroluminescence of silicon vacancy color centers (SiV centers) in the diamond p-i-n diode at high current density of 500 A/cm2 is presented. To create color centers, the internal region of the diode was doped with silicon. In the electroluminescence spectrum, the bright emission line at 738 nm corresponding to the SiV color center in a negative charge state was observed. Such bright emission is due to high current density. Additionally, the 946 nm line corresponding to the emission of the color center in a neutral charge state was observed in electroluminescence. Nanosecond voltage pulses were applied to study electroluminescence in a pulsed regime. Short emission pulses at 738 nm were demonstrated, showing the potential of creating electrically driven single photon source with “photon on demand” capability. By comparing the intensities of photoluminescence and electroluminescence, the possibility of obtaining single photon emission rate in a diode exceeding 106 photon/s is shown.

The influence of methane plasma parameters on the deposition rate and on the content of the hydrogen and the sp3-carbon fraction in hydrogenated diamond-like carbon films (DLC) was investigated. It was shown that the proportion of the sp3-carbon fraction mainly depends on the inductive power and the argon addition to the plasma; the latter also contributes to a decrease of hydrogen in the films.

Hexagonal silicon polytypes have attracted significant attention within the scientific community due to their potential applications in next-generation electronics and photonics. However, obtaining stable heterostructures based on cubic and hexagonal polytypes is a challenging task. This study demonstrates the synthesis of thin layers of the hexagonal phase of silicon, specifically 9R-Si, using a conventional microelectronics technique—ion implantation. Implantation of Kr ^+ ions was performed through a SiO _2 layer, with thickness approximately twice the projected range of Kr ^+ ions, followed by high-temperature annealing. High-resolution transmission electron microscopy revealed that damage to Si substrate at the SiO _2 interface resulted in the formation of a thin amorphous layer, which recrystallized during annealing, leading to the formation of the 9R-Si polytype. It is presumed that mechanical stresses induced by implantation through the oxide layer promote hexagonalization during subsequent high-temperature annealing. The effectiveness of hexagonalization was found to depend on the substrate orientation. In addition to the formation of the 9R-Si phase, under the utilized implantation and annealing parameters, silicon exhibited light-emitting defects, with photoluminescence observed at a wavelength of approximately ∼ 1240 nm up to temperatures of about ∼ 120 K. The obtained results may find applications in silicon micro-, nano-, and optoelectronics.

Dispersions of graphene oxide and its reduced form have been obtained. The resulting dispersions were characterized by UV spectroscopy. The features of the graphene oxide reduction process in the composition of coatings deposited on solid substrates (aluminum, optical glass, KDP single crystal) by interaction with various reducing agents: hydrazine hydrate, formalin, ascorbic and citric acids, and ammonium citrate are studied. Surface structures were studied by Raman spectroscopy. The surface morphology of coatings and the defectiveness of graphene-like materials obtained by the reduction of graphene oxide dispersions on the surface of substrates have been studied.

A technique is proposed for the formation of a developed regular structure on the surface of a polished single-crystal silicon wafer by ion-beam etching. It is shown that when single-crystal silicon is etched by a beam of accelerated Ar + ions with normal ion incidence on the sample surface, a surface region with a developed relief is formed, which can serve as a reflection-reducing layer. The reflection of radiation with wavelengths of 532, 633, 780, and 980 nm from a sample of single-crystal silicon with the orientation of the surface cut {100}, subjected to ion-beam treatment with Ar + ions with an energy of E ion = 400 eV for 10 hours (material removal was 7.5 µm) is studied. The specular-reflection curves of s -polarized radiation are obtained as functions of the angle of incidence. A decrease in the reflection coefficient relative to a polished silicon wafer is found at all investigated wavelengths. The largest decrease (more than 4 times) is recorded for a wavelength of 532 nm. It is shown that the range of heights of inhomogeneities formed during ion-beam etching increases linearly with an increase in the depth (time) of etching, which can be used to optimize the relief for a given wavelength.

In this paper, we propose a method for predicting the refractive index variation in InGaAlAs tunnel-coupled quantum wells under the action of an electric field. Complex of mathematical and experimental studies to optimize the heterosystems design forthe semiconductor modulator construction according to a planar Mach-Zehnder interferometer scheme is demonstrated.

In this paper, we propose a method for predicting the refractive index variation in InGaAlAs tunnel-coupled quantum wells under the action of an electric field. Complex of mathematical and experimental studies to optimize the heterosystems design forthe semiconductor modulator construction according to a planar Mach--Zehnder interferometer scheme is demonstrated. Keywords: Mach--Zehnder modulator, nanoheterostructure, quantum mechanical calculations, refractive index, transmission electron microscopy, photoelectric spectroscopy.

In paper the influence of parameters of inductively coupled chloropentafluoroethane plasma on the rate and characteristics of gallium arsenide etching was studied. Etched GaAs profiles by white light interferometry and scanning electron microscopy were investigated. It turned out that the process rate does not depend on freon flow, but forward and inductive power, as well as pressure determined. In this case, when the power of the plasma generator increase, the surface morphology changes significantly, that manifests itself in roughness increase and the detection of defects on GaAs and mask. Carrying out a process at low pressure leads to the deposition of single large inhomogeneities on the substrate. The transition from pulsed to continuous etching is accompanied by deterioration in the anisotropy of a process due to the polymer layer deposition on side walls.

In paper the influence of parameters of inductively coupled chloropentafluoroethane plasma on the rate and characteristics of gallium arsenide etching was studied. Etched GaAs profiles by white light interferometry and scanning electron microscopy were investigated. It turned out that the process rate does not depend on freon flow, but forward and inductive power, as well as pressure determined. In this case, when the power of the plasma generator increase, the surface morphology changes significantly, that manifests itself in roughness increase and the detection of defects on GaAs and mask. Carrying out a process at low pressure leads to the deposition of single large inhomogeneities on the substrate. The transition from pulsed to continuous etching is accompanied by deterioration in the anisotropy of a process due to the polymer layer deposition on side walls. Keywords: chloropentafluoroethane, plasma-chemical etching, inductively coupled plasma, gallium arsenide.

In this study, the dependence of the plasma-chemical-etching rate and the surface roughness of a gallium-arsenide crater on the concentration of chloropentafluoroethane (C2F5Cl) in a mixture with chlorine, the capacitive discharge power, and the etching duration are investigated. The characteristics of the GaAs etching crater are studied by white-light interferometry and scanning electron microscopy. It is shown that the addition of C2F5Cl into the chlorine-containing inductively coupled plasma leads to a nonlinear change in the gallium-arsenide etching rate with time, which can be explained by passivation of the substrate surface at the initial stage by the products of freon decay. Along with this, characteristics of the etching profile of GaAs are substantially improved. An increase in the capacitive discharge power promotes the development of roughness, while the etching rate increases nonlinearly.

This paper summarizes the results of studying the creation of localized ensembles of NV centers in a single-crystal diamond. The diamond was doped with nitrogen during its CVD growth. Due to the use of a microwave CVD reactor, in which a rapid (a few seconds) change in the composition of the gas mixture is realized, thin (nanometer thick) doped diamond layers were obtained, the position of which relative to the substrate surface is known with high accuracy. The possibility of forming a matrix of NV centers localized on the crystal surface is demonstrated. The results of studying the fluorescence of NV centers in such structures are presented.

In this work, the dependence of plasma-chemical etching rate and the roughness of the surface of gallium arsenide crater on chloropentafluoroethane (C2F5Cl) concentration in a mixture with chlorine, forward power and etching duration were studied. Characteristics of GaAs etching crater were studied by white light interferometry and scanning electron microscopy. It is shown that C2F5Cl addition in chlorine-containing inductively coupled plasma led to a nonlinear change of gallium arsenide etching rate with time which can be explained by passivation of substrate surface at the initial stage by products of freon decay. Along with this, characteristics of the etching profile of GaAs are significantly improved. Forward power increase contributes to development of roughness, while the etching rate increases nonlinearly.

A new approach to the analysis of carbon-containing materials by the method of secondary ion mass spectrometry is studied, which allows one to determine the concentration of carbon atoms in the states of sp2 and sp3 hybridization. It is proposed to use the ratio of the intensities of cluster secondary ions C8/C7 as the main parameter of the mass spectra of secondary ions characterizing the concentration of N(sp3). From measurements of several test structures, a calibration dependence of N (sp3) on the C8/C7 ratio was obtained. The N(sp3) profiles of diamond-like carbon samples grown on diamond and silicon substrates were measured, showing an N(sp3) concentration of 0.3 to 0.6 for different growth modes and an inhomogeneous distribution of the N(sp3) concentration over the thickness of the samples.

We have studied a new approach to the analysis of carbon-containing materials by secondary ion mass spectrometry (SIMS), which allows determining the contents of carbon atoms in sp 2 and sp 3 hybridization states. According to this, the main SIMS parameter characterizing the atomic concentration N ( sp 3 ) is defined as the intensity ratio of C8/C7 secondary cluster ion peaks. Based on the results of SIMS analysis of several test compositions, a calibration dependence of N ( sp 3 ) versus C8/C7 peak intensity ratio has been obtained. The depth profiles of N ( sp 3 ) for diamond-like carbon (DLC) grown on diamond and silicon substrates were obtained, which showed (i) N ( sp 3 ) variation from 0.3 to 0.6 depending on the DLC growth regime and (ii) inhomogeneous distribution of N ( sp 3 ) in depth of the samples.