Registration Number
0215U001084,
0114U005147
, R & D reports
Title
Device Inspiring Research and Technology Demonstration and Assessments for High-Speed and Low-Energy Nanowire Transistors
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Head
Kochelap Vyacheslav Olexandrovich,
Registration Date
16-01-2015
Organization
Institute of Semiconductor Physics of National Academy of Sciences of Ukrain
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Under this stage the study of high-field and high-frequency electron transport in nanowire structures based on AlGaN/GaN heterostructures and transistor structures based on Si has been carried out. It was performed theoretical modeling of electrostatic potential profiles and electrical transport characteristics of the nanowire structures. For the analysis of the effects of electron trapping that take place in the AlGaN/GaN quantum heterostructures it was carried out the investigations of the low-field current-voltage characteristics. The temperature dependencies of the conductivity of nanowires including the dependencies vs geometrical width of nanowires and wavelength of illumination were obtained. It was shown that nanowires with the widths less 200 nm are almost depleted at this the critical width of depletion does not depend on temperature. However, there is essential dependence of the quantity on the wavelength of ultraviolet illumination. With decreasing of wavelength the critical width is decreasing. These investigations allow to formulate the following conclusion: in the samples under the study the electron are trapped on the deep interface states. Also, it were measured high-field current-voltage characteristics. The observable non-ohmic and super-liner behaviors of current-voltage characteristics relates to the effect of space -charge limiting transport and non-ohmic properties of current contacts. It was developed the theoretical model of the calculation of the free electron distribution and the form of built-in electrostatic potential. It was illustrated that even under the equilibrium the effect of electron trapping results in the formation of strongly-nonuniform distribution of electrostatic field in the environment (the average length of field localization can reach the several microns). These results were used at the development of the high-frequency theory of ballistic electron transport in the nanowires with built-in electrostatic potential. It was found that in the nanowires under the study the geometrical resonance can occur, that can manifest itself as resonance absorption of high-frequency (terahertz) radiation. The resonance frequencies and the forms of absorption band are strongly depend on the temperature, geometrical width and form of electrostatic potential. These results can be used for the characterization of electrical properties of nanowires by means novel methods of THz spectroscopy.
Product Description
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А. В. Наумов
В.В. Коротєєв
О. Є. Бєляєв
С. М. Кухтарук
Ю. М. Лящук
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2020-04-02
