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The PHEMT epitaxial structures with a doping profile in the form of tin nanowires were fabricated using vicinal GaAs substrate disoriented by 0.3° in relation to accurate orientation (100). Investigation of electron transport properties of the structures with nanowires of tin atoms on vicinal GaAs substrates have been presented. It was determined that non-optimal growth temperature of cap layers leads to degradation of electrophysical parameters of the samples and prevent forming of tin one-dimensional channels. Anisotropy of the saturation current on current-voltage characteristics was obtained when current flow along and across nanowires. Field effect transistors with special topology for orthogonal current flow were fabricated and frequency characteristics were measured. The evident anisotropy of the frequency characteristics for PHEMT was shown. Gain coefficient MSG (Maximum Stable Gain) of the fabricated PHEMT for current flow along nanowires correlates to best-achieved values of MSG for GaAs PHEMT.

It is proved that a prospective direction of electronic power development are intelligent power components: integrated power ICS and modules. Power electronic devices in the field of switched currents up to 50 A are arranged. The results of the semiconductor structures manufacturing technology study, field effect transistor type KP 961 are summarized. The manufacturing technology optimization problem of the transistor structures for power electronics to improve the output characteristics and reliability of the device has been solved. Special attention is paid to the reliability increasing methods, stability and durability of transistors in various modes and operating conditions. To improve the technology some computational model for the stock and the sealing areas formation have been obtained as well as experimental studies have been carried out. Optimised process stages of the transistor structure formation have been proposed. The charts on the structures of transistors grown at the given technology have been made. The manufacturing technology route structure of a field effect transistor of the KP 961 type has been developed.

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Generating sensors provide the possibility of getting remote information and its easy conversion into digital form. Typically, these are one-parameter sensors formed by combination of a primary transmitter (PT) and a sine wave generator. Two-parameter sensors are not widely used as their implementation causes a problem with ambiguity output when measuring the PT. Nevertheless, the problem of creating miniature, thrifty multi-parameter RF sensors for different branches of science and industry remains relevant. Considering ways of designing RF sensors, we study the possibility of constructing a three-parameter microwave radio frequency range sensor, which is based on a two-stage three-parameter generalized immitance convertor (GIC). Resistive, inductive and capacitive PT are used as sensing elements. A mathematical model of the sensor, which describes the relation of the sensor parameters to the parameters of GIC and PT was developed. The basic parameters of the sensor, its transfer function and sensitivity were studied. It is shown that the maximum value of the power generated signal will be observed at a frequency of 175 MHz, and the frequency ranges depending on the parameters of the PT will be different. Research results and adequacy of the mathematical model were verified by the experiment. Error of the calculated dependences of the lasing frequency on PT parameters change, compared with the experimental data does not exceed 2 %. The relative sensitivity of the sensor based on two-stage GIC showed that for the resistive channel it is about 1.88, for the capacitive channel –1,54 and for the inductive channel –11,5. Thus, it becomes possible to increase the sensor sensitivity compared with the sensitivity of the PT almost 1,2—2 times, and by using the two stage GIC a multifunctional sensor is provided.

The method for compensation of 2-nd and 3-rd order nonlinear distortions in multistage amplifiers is considered. It is shown, that equalization of nonlinear components in multistage structures is determined by schemes of one-from-last and last cascades. Realization of multistage amplifier for reducing 2-nd and 3-rd order nonlinear distortions is proposed.

It is shown that the threshold voltage of a GaAs ion-implanted metal-semiconductor field-effect transistor corresponds with a good accuracy to the voltage at which an inflection point appears in the capacitance-voltage characteristic. A method for predicting the threshold voltage of ion-implanted field-effect transistors using capacitance-voltage measurements prior to contact formation is proposed.