Piezo-and pyroelectric GAAS sensors integrated in one crystal with GAAS FET

One of important problems of recent electronics is non-cooled pyroelectric and piezoelectric sensors. They are realized usually in a hybrid integrated chip where thousands of ferroelectric ceramic elements are integrated with transistor matrix. Reported research work is devoted to the possibility of realization of one-crystal pyroelectric sensor. We revealed new effect of symmetry decrease that is used as a basis to develop one-crystal pyroelectric or piezoelectric sensor array using III-V crystals. In feasible sensor devices, the transducer, the amplifier and read-out electronics would be the various parts of one crystal chip. Voltage sensitivity of semi-insulating GaAs-type temperature sensor is the same as one of PZT pyroelectric ceramics. However, proposed device will be fully made from GaAs and related crystal layers by the standard in the micro-electronics technolog

Acoustic emission and methods of its registration (review)

Lately a tendency is observed for the steady growth of requirements applied both to construction materials as well as to the methods of estimation of their reliability and quality. Particular attention is paid to the development of new, physically reasonable criteria of structural durability of materials, based on comprehensive study of the phenomena, which form the basis of processes of deformation and fracture. Such approach is supposed to enhance our understanding of the nature of durability and mechanisms of fracture of materials on different scale levels. This is possible only when analysis of these phenomena is accomplished by means of modern physical research methods as well as applying acoustic emission techniques for diagnostics of the fractures

Defect diagnostics in devices via acoustic emission

The research was conducted to explore conditions triggering degradation and deterioration processes in heterostructures using methods of acoustic emission. Current, flowing through materials, causes significant temperature gradients and thermo-mechanical stress (up to 107 Pa) that contributes to the development of undesirable microplasticity of the material. The research disclosed peculiarities of acoustic emission in n+-n-p- and p+-p-n- structures of A3B5 compounds under direct current in a process of their natural deterioration, and interdependence between the acoustic emission and developments in their electrical characteristics. The research facilitates direct and timely detection of defects and microcracks in different devices operating under threshold parameters and being influenced by external physical/mechanical forces generated from direct current and ultrasonic fluctuation

The study of ferroelectric thin films on silicon substrates

In recent years, intensive development of field-effect transistors on metal-ferroelectric-semiconductor for use, as non-volatile memory elements. The principle of operation of these devices is as follows. Ferroelectric film contains a large number of domains, having a certain vector of electric polarization. Total polarization of the individual domains gives spontaneous (spontaneous) polarization film (non-zero resultant dipole moment per unit volume of the sample). Module and spatial orientation of the spontaneous polarization can be changed under the influence of an external electric field. In strong fields, the film becomes a single-domain. The application of a strong electric field in opposite directions on a certain part of the surface can lead to a reversal of the ferroelectric domains of the film within this area that lends itself to registration. Thus, the effect of polarization in ferroelectric films allows you to create non-volatile memory devices, data carriers which are the domain reversal. These devices have several advantages over traditionally used magnetic and optical data carriers. The purpose of this paper is to study the possibility of using ferroelectric films of complex oxides deposited on original technology on a silicon substrate as a recording media storage devices for external storage

The analysis of defects propagation in navigating electronic devices

Defects in the form of microcracks in ??8?12 contacts of passive electronic components of navigating devices operating at different temperatures and pressure were analyzed. Research results have demonstrated the possibility of early prevention of potential accidents. Microscopic studies are systematized depending on various physical and chemical influences on devices. The mathematical model for defects definition in local points of contacts with an error of about 5 – 7.5 % has been applie

Diagnostics of nano-particles on a surface and in volume of a solid body

In this research work the results of change of In, Sn, Bi, Pb nano-layers melting temperature on a surface and in Al and Ge matrixes depending on thickness and interaction character of components by methods of electron microscopy and x-ray diffractometry are presented. Layered film systems Al-Me-Al, Ge-Me-Ge (Me = Pb, Sn, Bi, In) were the object of researches. The purpose of work was the research of the general law of noted systems melting depending on the specific size and conditions of their formation. Layered film systems prepared by consecutive condensation of components in vacuum and their evaporation from independent sources. The film microstructure before and after melting was investigated by method of electron microscopy. The structure and phase composition of film systems defined using x-ray diffractometry. Melting temperatures and specified eutectic temperatures for In, Sn, Bi and Pb binary systems with aluminium and germanium registered by differential method. It is shown, that for layered film systems Al-Me-Al, Ge-Me-Ge (Me = Sn, Bi, Pb, In) eutectic temperature decreases with reduction of thickness of Me film. The urgency of the work is caused due to necessity of understanding the physics of processes in nano-systems, and wide use nano-objects in modern technologie

Acoustic emission and methods of its registration (review)

Lately a tendency is observed for the steady growth of requirements applied both to construction materials as well as to the methods of estimation of their reliability and quality. Particular attention is paid to the development of new, physically reasonable criteria of structural durability of materials, based on comprehensive study of the phenomena, which form the basis of processes of deformation and fracture. Such approach is supposed to enhance our understanding of the nature of durability and mechanisms of fracture of materials on different scale levels. This is possible only when analysis of these phenomena is accomplished by means of modern physical research methods as well as applying acoustic emission techniques for diagnostics of the fractures

The analysis of defects propagation in navigating electronic devices

Defects in the form of microcracks in ??8?12 contacts of passive electronic components of navigating devices operating at different temperatures and pressure were analyzed. Research results have demonstrated the possibility of early prevention of potential accidents. Microscopic studies are systematized depending on various physical and chemical influences on devices. The mathematical model for defects definition in local points of contacts with an error of about 5 – 7.5 % has been applie

Diagnostics of nano-particles on a surface and in volume of a solid body

In this research work the results of change of In, Sn, Bi, Pb nano-layers melting temperature on a surface and in Al and Ge matrixes depending on thickness and interaction character of components by methods of electron microscopy and x-ray diffractometry are presented. Layered film systems Al-Me-Al, Ge-Me-Ge (Me = Pb, Sn, Bi, In) were the object of researches. The purpose of work was the research of the general law of noted systems melting depending on the specific size and conditions of their formation. Layered film systems prepared by consecutive condensation of components in vacuum and their evaporation from independent sources. The film microstructure before and after melting was investigated by method of electron microscopy. The structure and phase composition of film systems defined using x-ray diffractometry. Melting temperatures and specified eutectic temperatures for In, Sn, Bi and Pb binary systems with aluminium and germanium registered by differential method. It is shown, that for layered film systems Al-Me-Al, Ge-Me-Ge (Me = Sn, Bi, Pb, In) eutectic temperature decreases with reduction of thickness of Me film. The urgency of the work is caused due to necessity of understanding the physics of processes in nano-systems, and wide use nano-objects in modern technologie

Перспективные направления развития термометрии

У роботі наведено огляд сучасних технічних розробок в сфері наномасштабної термометрії і надається опис переваг можливостей їх використання. Розглянуто еволюцію розробки термометрії й доведення сучасних конструкцій до нанорозмірних розмірів, у тому числі динамічний нанотермометр на основі надструктурних наночасток, вуглецевих нанотрубок, начинених фулеренами тощо. У сфері сучасних нано- і біотехнологій досягнення вимагають застосування точної термометрії, де неможливо здійснювати вимірювання за допомогою традиційних методів. Однак, розробка нанорозмірного термометра – проблема, пов’язана не тільки з розміром, але також з потребою у матеріалах із новими фізико-хімічними та термодинамічними властивостями. Тому особливу увагу приділено новому напряму в термометрії – просування в сфері створення теплових датчиків із використанням молекулярних і біологічних часток, а також нанорозмірних надструктур.This paper gives an overview of current technical developments in the field of nanoscale thermometry and the advantages to their use is describen. The evolution of the development of thermometry and bringing contemporary designs to nanoscale dimensions, including dynamic nanothermometer superstructure nanoparticles, carbon nanotubes, fullerenes etc. stuffed. In the field of modern nano- and biotechnology achievements require accurate thermometry, where it is impossible to carry out measurements using traditional methods. However, the development of nanoscale thermometer is a problem related to not only in size but also with the need for new materials with physics, chemical and thermodynamic properties. Therefore, special attention is given to the direction in thermometry as development of thermal sensors using molecular and biological particles and nanoscale superstructure.В работе приведен обзор современных технических разработок в сфере наномасштабной термометрии и дано описание преимуществ возможностей их использования. Рассмотрена эволюция разработки термометрии и доведения современных конструкций до наноразмерных размеров, в том числе динамический нанотермометр на основе надструктурных наночастиц, углеродных нанотрубок, начиненных фуллеренами т.п. В области современных достижений нано- и биотехнологий требуется применение точной термометрии, где невозможно осуществлять измерения с помощью традиционных методов. Однако разработка наноразмерного термометра является проблемой, связанной не только с размером, но также с потребностью в материалах с новыми физико-химическими и термодинамическими свойствами. Поэтому особое внимание уделено новому направлению в термометрии – созданию тепловых датчиков с использованием молекулярных и биологических частиц, а также наноразмерных сверхструктур