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The lithological features of the Middle Devonian sediments of the Skhidnosaratska structure of the Dobrudja Foredeep in the aspect of their influence on the formation of reservoir rocks and hydrocarbon reservoirs have been considered. Nine lithocycles of regressive nature (e-1 – e-5; g-1 – g-4), characterized by a two-membered structure have been identified in the section. Each lithocycle represents a separate productive horizon. The lower parts of the latter are composed of porous and fractured reservoir rocks (limestones, dolomites, siltstones, sandstones), and the upper parts are composed of fluid-resistant packs (marls, anhydrites).Features of cyclic sedimentation conditions caused spatial-age variability of trap localization and morphology, nature of distribution of reservoir rocks of various types, and post-sedimentation processes caused spatial heterogeneity of petrophysical properties of rocks, which entailed different prospects for individual areas of the Skhidnosaratske deposit. The vaulted traps of the productive horizons of the Eifelian deposits tend to the area of borehole 2, and the Zhivetian deposits to the borehole 1. Consequently, in the first case, the most perspective horizons are e-2 and e-3, in the second – g-2 – g-4. Often more powerful packs of better-quality reservoir rocks are developed outside the vault, which leads to the formation of lithological traps in the e-1 and e-2 horizons. It has been shown that the complex structure (presence of layers of carbonate and terrigenous rocks) of fluid-resistant marl-sulfate packs could cause dispersion of hydrocarbons and thus reduce the prospects of individual horizons, in particular, e-2 and e-3. The established heterogeneity of the structure of the productive horizons, the pinching out of individual packs of both pore and fractured reservoirs, the spatial uneven development of the limestones anhydritization and dolomitization processes give possibilities to suggest the formation of separate deposits with different hypsometry of water-oil contacts.

Studies in the field of the development of new structures of Hall sensor with improved characteristics, in particular with increased magnetic sensitivity are in high demand. A physical model is proposed, which explains features of the Hall–hate characteristic and the formation of the increased magnetic sensitivity region in the SOI field-effect Hall sensor (SOI FEHS). The results of simulation in the Synopsys TCAD system confirm the proposed physical model of SOI FEHS functioning. The model explains features of the Hall–gate characteristic of the SOI FEHS in a wide range of gate voltages and allows the conclusion that the SOI FEHS has two operating regions and their choice is dictated by specific conditions of the sensor application. To achieve the maximum magnetic sensitivity, regions of partial depletion and enhancement should be chosen. To provide high noise immunity, it is reasonable to choose the full enhancement modes.

The characteristics of thin-film Si MISIM magnetic transistors with a built-in accumulated channel and partially depleted quasi-neutral area are studied. The design of transistors is integrated with a Hall element. It is shown experimentally that transistors of this type, which were named field-effect Hall sensors (FEHSs) and made by the “silicon-on-insulator” (SOI) technology, provide measurements of the magnetic induction in a temperature range of 1.7–605 K. Theoretical estimates show that the upper operating temperature limit of the FEHS can be about 850 K.

We describe a magnetosensitive device consisting of a combination of a thin-film Si transistor with built-in conducting channel (fabricated by the silicon-on-insulator technology) and a Hall-type sensor (HS). The transistor has a double-gate field control system of the metal–insulator–semiconductor–insulator–metal type and operates in the regime of carrier accumulation in the channel at partial depletion of adjacent regions of the Si film. It is established that the device can operate at temperatures up to about 350°C, which is 160–180°C higher than the maximum operating temperature of HSs based on bulk Si crystals and comparable with HSs based on wide-bandgap semiconductors.

On the example of the magnetic field sensor shown that the developed sensing element type thin-film SOI MISIM transistor with built-in channel provides the creation of sensors with substantially improved electrical characteristics (magnetic sensitivity, temperature range). The physical model of a sensor is considered and justified the choice of the optimal electrical regimes. It is shown that the operation temperature range of the magnetic sensing element is from LHT up to at least 330 °C. Theoretically predicted the possibility of increasing the temperature limit by 200–300 °C depending on the functional purpose of the sensor. Developed and implemented microelectronic operating voltage stabilizers of sensors and electronic keys operating at temperatures of 230 °C and not less than 300 °C, respectively. It is shown that the developed sensor and functional elements provide to create multifunctional multi-channel high-temperature sensor of magnetic field and temperature.

The construction of Si Hall element formed in thin Si layer of SOI structure is considered. Hall element is a part of SOI FET accumulation mode transistor with built-in channel and MISIM field control systems. Such Hall element characterized by wide range of operation temperature from liquid Helium temperature up to 650K.

Autogenerator magnetic field converter circuits based on a field-effect Hall sensor (FEHS), are considered. The feasibility of creating microelectronic high-sensitive magnetic-field sensors with a frequency output and regulated operating frequency is shown. A FEHS-based induction-to-frequency magnetic field converter circuit is tested. The converter sensitivity is 100−600 Hz/mT, the stability of the operating frequency of the autogenerator is 1%, and the operating frequency can be controlled by changing potentials of the FEHS gates in the range of 6−20 kHz.

A stabilizer of micro- and small currents based on a field Hall-effect sensor is considered. The field-effect Hall sensor is an integration of a conventional Si Hall element and an Si thin-film doublegate field-effect transistor. It is shown that formation of feedbacks between Hall contacts, field gates, and power sources makes it possible to stabilize the sensor current with accuracy of not worse than 1% when the load resistance changes by an order and the temperature varies in the 25–65°C range.