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The films of a new ternary compound, silicon carbonitride, were synthesized by means of plasma enhanced deposition (PECVD) using hexamethyldisilazane Si₂NH(CH₃)₆ as the precursor. Different investigation methods, namely, IR and Raman spectroscopy, XPS, ellipsometry, electron microscopy, including high-resolution me-thods (HRTEM, SAED) were applied to study physico-chemical properties of the films. Much attention was paid to the development of the X-ray phase analysis methods involving synchrotron radiation to determine the structure and phase composition of thin films. It was established that the silicon carbonitride films contain nanocrystals 2-5 nm in size distributed over the amorphous matrix.

Physicochemical transformations that take place in thin nanocrystalline layers of silicon carbonitride as a result of thermal annealing in vacuum at a temperature of 1173 K are investigated. IR, Raman spectroscopy, XPES, ellipsometry and X-ray analysis are applied to study these physicochemical transformations. It is stated that high-temperature annealing of the silicon carbonitride films helps decreasing the amorphous constituent of the film, increasing the density and size of nanocrystals incorporated in the film.

The results of works aimed at mastering the technology of obtaining NTD silicon, carried out at the KEPP Corporation in collaboration with L. Ya. Karpov NIFKhI, are reported. The results include optimization of the annealing mode, for the purpose of increasing the minimal lifetime of charge carriers from the values observed (100-200 s) to 200-400 s, the specific resistance being about 50 Om^.cm. The regimes developed as a result of the investigations allowed us to decrease the time of thermal treatment necessary for the annealing of radiation defects and, as a consequence, to increase the lifetime of auxiliary charge carriers. The analysis of the results on obtaining NTD silicon grown from the initial polycrystalline silicon of different manufacturers allows us to conclude that further routes to increase the lifetime in NTD silicon are connected mainly with mastering the technology of obtaining the initial material.

The properties of the interface in isotype structures formed by solid-state bonding (SSB) of silicon wafers with the same type of conductivity are investigated depending on the technology of bonding. In order to reveal the role of oxygen in the electric properties of the interface, bonding was carried out both using the wafers coated with the natural oxide (not thicker than 1-2 nm) and using specially oxidized ones (with silicon oxide layer up to 20 nm). The investigation of bicrystals bonded after bringing together in air or deionized water, demonstrated that in this case the electric activity of the interface is determined mainly by the degree of its enrichment with oxygen and contamination of the surfaces of wafers to be bonded with acceptor impurities (presumably aluminium). Electric activity of oxygen-free interface in the structures obtained by combining wafers ion etching and annealing in vacuum depends mainly on mismatching of the lattices of wafers to be spliced. The properties of SSB structures with the buried oxide layer obtained by bonding of the silicon wafers of n-type conductivity are determined by the contamination of the bonding interface with an acceptor impurity.

Semiconductor power devices are employed widely in pulsed power applications. A first goal of device development for the applications is to establish high di/dt characteristics similar to that of spark gap switches, namely, 10¹²A/s. We examined turn-on characteristics of SI-thyristors for fast high-voltage pulse generators. The SI-thyristors have a buried gate structure in which the gate electrodes are placed in n-base region. Since they are normally on-state, gate electrodes must be negatively biased to hold off-state. The SI-thyristors at on-state behave similar to pin diodes. We characterized three kinds of SI-thyristors, two of which were for power electronics use with a rated voltage of 4000 V. The device named RT201 was designed for pulsed power applications. The difference among them is device structures at the vicinity of anode. The punch-through and anode shorted structures are commonly used to improve turn-off characteristics for power electronics. The RT201 device with a rated voltage of 5500 V has the punch-through structure and is not an anode-shorted device. The turn-on speed is mainly determined by carrier injection rate to the n-base region. Therefore performance of the gate driving circuit influences fast turn-on characteristics. When the newly developed high current gate driver was used, the fastest turn-on operation with Tf = 35 ns and di/dt = 9.5*10¹⁰A/s was obtained in the RT201 device. We made a stacked SI-thyristor switching unit to characterize repetitive and higher voltage operation. The stacked unit comprised three SI-thyristors, and each of them had the gate driver. The switching unit was successfully operated with the repetition rate of 2 kHz at 10 kV.

Information is presented on the modern status and outlooks of the production of power electronic devices (PED) at the Elektrovypryamitel' JSC. It is demonstrated that the development and introduction into large-scale manufacturing process of all the modern PED classes earlier manufactured in the USSR, as well as qualitatively new types of devices, i.e. high-power high-voltage semiconductor devices developed on the basis of broad introduction of the achievements of science and technology, allowed achieving the outstanding industrial results and solving the most important problem of the national economy aimed at the provision of all the branches of industry of the Russian Federation with modern classes of reliable and high-efficiency home-manufactured semiconductor devices, including those for energy- and resource-saving technologies, modern armament systems, electrified transport, municipal services, excluding the dependence on import, which makes an important constituent of the conservation of national safety and economic independence of Russia.

The results of development and manufacture of MOS controlled thyristors (MCT) are presented. Static and dynamic characteristics are studied. The effect of the irradiation with electrons on the static and dynamic characteristics is investigated. It is found that the irradiation with electrons provides a substantial decrease of the MCT turn-off time. Also an increase of the density of controllable current was observed.

A design of high-voltage IGBT transistor is proposed. The transistor is manufactured on a high-resistance substrate using the NPT technology. Numerical modeling of the manufacture and of the static voltage-current characteristics is carried out. The possibility to increase the working voltage to 1800 V is demonstrated.

A technology is developed for obtaining power Au-TiB_x-n-n+-GaAs Schottky diodes of planar and mesa structures and with integrated heat sink. The effect of thermal annealing (at T = 500

An opto-capacitive transducer is proposed which is able to transform optical energy into electric signal through the changes of the capacitance of a solid structure. The transducer involves the semiconductor's feature to change surface resistance under the action of optical radiation. The capacitance of the solid structu-re is changed due to the change of the surface resistance of gallium arsenide (GaAs). Opto-capacitive transducer allows detecting optical radiation, measuring the changes of capacitance depending on the changes of the width of light spot, radiation power, radiation frequency. Along with the possibility to control, re-cord and transform optical radiation into electric signal, it allows recording metal bodies and measuring distance from them. On the basis of the opto-capacitive transducer, it is possible to develop various devices to detect and record the light signal, to measure the optical radiation power; it is also possible to develop transformers of optical energy into electric signal, various sensors for shift, force, pressure, etc.