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Various issues of development of an algorithm for motion of the measuring module of an automated system for nondestructive quality testing of the soldered joints of the engine nozzle are discussed. The object of testing is identified as that with a complex geometric shape with flaws in the soldered joints of the test object formed during the manufacturing process. The defects studied in this paper are the “dry joint,” “partially dry joint,” and “cold lap.” The relevance of the development, as well as the problems of production and testing of engine nozzles, which do not allow the required defects to be identified at the early stages of manufacturing assembly units without destroying the integrity of the engine nozzle, are substantiated. The existing approaches are described in terms of the choice of methods and means for nondestructive testing of engine nozzles of complex geometric shapes; their advantages and disadvantages are identified. The existing problems in terms of automation of the pulse-echo and through-transmission methods of ultrasonic testing are analysed; the advantages and disadvantages of the proposed methods are identified. The main factors that reduce the probability of detecting defects are determined, namely, the instability of the acoustic contact between the transducer and the test object, as well as the deviation of the acoustic axis of the transducer from the normal to the surface of the test object. The requirements to the algorithm of motion of the measuring module of an automated nondestructive testing system with feedback based on the signal amplitude measured during scanning the signals from the structural elements of the internal structure of the engine nozzle are determined.

A preparation method is described in detail, which allows one to obtain defect-free cross sections of heterostructures for transmission electron microscopy and ensures the achievement of atomic resolution over a large area. The method is illustrated with examples of studying heterointerfaces of complex shape, selective oxidation, and selective etching of superlattices.

Photosensitive germanium layers on a silicon substrate have been formed by molecular beam epitaxy. The structural, optical and photovoltaic characteristics of the films have been investigated. The data obtained confirm the possibility of utilizing the developed Ge-on-Si heterostructures for the fabrication of photodetectors in the spectral range of 1.3-1.55 μm.

In this study, the electrical, morphological, and optical properties of thin aluminum films obtained by magnetron sputtering on SiON are studied. It is found that the growth of Al films on SiON follows the Stransky─Krastanov mechanism. At the stage of 3D growth, films with a cluster structure of Al grains and a pit/pore size of up to 20-50 nm are formed. For multilayer porous Al/SiON stacks, absorption of up to ~82% in the range of 1-4.2 µm and a redshift with an increase in the number of layers are observed. The analysis of optical losses of porous Al films, carried out by numerical modeling, shows the presence of optical absorption bands with a linear increase in the position of the absorption maximum λ_max at an increase in the thickness of the Al film, as well as a shift of λ_max to the long-wavelength region with a decrease in the size of Al clusters and pores between them.

We demonstrate the possibility of designing a semitransparent heater based on thin gold films. A thin 15 nm thick gold film with a surface resistivity of 3.5 Ω/□ and a transmittance in the visible range of 0.4 is deposited on a quartz substrate by pulsed laser deposition. The maximum heating temperature of the semitransparent heater is 113 °C at an applied power of 1.2 W. When a voltage is applied, the heating rate varies between 1-2 °C/s, and the rate rapidly decreases as the temperature approaches a steady state.

Using the catalytic chemical vapor deposition method, VACNT arrays with a height of 25 to 100 μm and a resistivity of 1.5 to 4 Ohm ⋅ cm have been grown for the first time on a Si/HfO₂/Fe surface. The growth of VACNTs on hafnium oxide is observed in the temperature range T = 625-725°C, but is not realized at T ≥ 750 °C. In this case, the temperature dependence of the VACNT growth rate is characterized by a value of ~1.5 eV. Using high-resolution scanning electron microscopy and Raman spectroscopy, the dominant presence of nanotubes with diameters from 1 to 10 nm in the array is shown. It is found that nanocrystallization of HfO₂ during annealing of substrates complicates the SEM analysis of catalytic Fe particles whose size on the surface of the initial amorphous HfO₂ is 2-5 nm.

The manuscript considers fundamental research in the field of nanomechanics of corrugated semiconductor nanomembranes composed of strained heterostructures. The results of a study of the magnetotransport of a two-dimensional electron gas in a corrugated nanomembrane made of a GaAs/InGaAs heterofilm are presented.

The results on the miniaturization of silicon-on-insulator (SOI) structures and SOI elements of integrated circuits (IC) are presented. To increase the IC performance, it is necessary to increase barriers and pulling electric fields due to high-k dielectrics and nanoscales, which lead to a noticeable decrease in the mobility of charge carriers with a decrease in the channel length and thickness. This, along with an increase in leakage due to source-drain tunnel currents, limits the physical length of the channel to 10 nm even when replacing silicon with two-dimensional (2D) materials such as graphene and metal dichalcogenides [1]. Three-dimensional (3D) integration in the form of double-gate transistors with complete depletion in SOI structures with a high-k buried dielectric (h- k BOX), in the form of the so-called fin transistors (FinFET) with two to four (gate-all-around ─ GAA) gates and channels of nanowires (NW FET), nanosheets (NS FET), nanoforks (FS FET), 2D materials and their 3D packaging allows one to increase the number of transistors on the chip, but not their performance. As an alternative, the option of increasing the functionality of the elements is considered, by replacing dielectrics in capacitors and transistors with ferroelectrics, and resistors with memristors, which leads to a transition from binary to neuromorphic logic, as well as to the implementation of the principles of radiophotonics, quantum devices, and sensors with parallel processing. A dynamically adjustable threshold and polarization of the gate ferroelectrics of complementary MOSFETs in heterosystems on a chip (SoC) will preserve ultra-low power consumption.

A strong response of nanosystems to the action of weak microwave power through the gap between the sample and the end of the coaxial cable from the microwave generator is detected by measurements at 4.2 K of the conductance of a short-channel p-type silicon transistor, as well as samples with a short quantum point contact in a two-dimensional electron gas of GaAs/AlGaAs heterostructures. The conductance response is gigantic in the tunnel regime of the devices; outside this regime, the sign of the microwave photoconductance depends on the mesoscopic state of the sample and the gate voltage interval under study. The mechanism of the discovered effects is elucidated by modeling mesoscopic transport within the framework of single-particle quantum mechanics and the Landauer formula, as well as by analyzing the basic circuits of electrical control of the semiconductor device. The main reason for the response of nanosystems to microwave exposure is found to be forced in-phase charge oscillations in contacts to the semiconductor due to capacitive connections in the near metallic environment of the sample.

Local anodic oxidation (LAO) of the Si(111) surface in the contact mode of an atomic force microscope (AFM) is studied depending on the relative humidity of the ambience - (35-75)% at two potentials U (-8 and -10 V) applied to the AFM probe. It is shown that LAO for U = -8V is realized at Θ ≥ 40% in the absence of growth of oxide lines in width; at U = -10V, their height and width increase linearly over the entire range of Θ values. Based on a detailed analysis of LAO and the deviation of the cantilever during the approach and retraction of the probe from the surface with variation of Θ without voltage on the probe, taking into account literature data for the semi-contact mode of AFM operation, a generalized model of the dependence of the LAO process on U and Θ is proposed.