Functional microelectronics
The principle of elemental (technological) integration, microminiaturization of elements (active and passive) of a microcircuit is the basis for the creation of an IC. In ICs you can distinguish areas, are active (diodes, transistors) and passive (resistors, capacitors, inductors) elements. Integrated microelectronics retains the basic principle of discrete electronics, based on the design of an electrical circuit according to the laws of circuit theory. This principle is inevitably associated with an increase in the number of chip elements and inter-element connections as the functions it performs become more complex.
Functional microelectronics offers a fundamentally new approach that makes it possible to implement a particular hardware function without using standard basic elements, based directly on physical phenomena in a solid body. In this case, the local volume of the solid is added to such properties that are needed to perform the function, and the intermediate step of representing the desired function in the form of an equivalent electrical circuit is eliminated. Functional circuits can be based not only on semiconductors, but also on such materials as superconductors, segmentelectrics, materials with photoconductive properties, etc. Phenomena that are not related to electrical conductivity can be used to process information (for example, optical and magnetic phenomena in dielectrics, the laws of ultrasound dissolution, etc.) Optoelectronics. An optoelectronic device is a device that converts electrical signals into optical signals and vice versa when processing information.
Optoelectronics usually uses a wavelength range of 0.2 µm – 0.2 mm. As a source of radiation gallium arsenide light diodes are used as photodetectors (photo receivers) – silicon photodiodes (photo diode) and phototransistors (photo resistor).
An essential feature of optoelectronic devices is that the elements in them are optically coupled but electrically isolated from one another. This makes it easy to match high-voltage and low-voltage as well as high-frequency circuits. In addition, optoelectronic devices have other properties: the possibility of spatial modulation of light beams (light beam), which in combination with changes in time gives three degrees of freedom (in purely electronic circuits – two), the possibility of significant branching and intersection of light beams in the absence of galvanic coupling between the channels; large functional load of light beams due to the possibility of changing their many parameters (amplitude, directions, phase frequency, polarization).
Optoelectronics covers two independent directions: optical and electron-optical. The optical direction is based on the effects of interaction of a solid body with electromagnetic radiation. It is based on holography (holography), photochemistry (photochemistry) Electrooptics and other directions of development. The optical direction is sometimes called the laser direction.
The electron-optical trend uses the principle of photoelectric conversion, which is realized in solids with the help of the internal photoelectric effect on the one hand, and electroluminescence on the other hand. This direction is based on the replacement of galvanic and magnetic bonds in traditional electronic circuits by optical ones. This makes it possible to increase the information density in the communication channel, its speed, and overshoot.
For microelectronics, the electron-optical direction is of interest mainly; it allows solving the main problem of integrated microelectronics – to significantly reduce parasitic connections between elements both within a single IC and between microcircuits. The optoelectronic principle can be used to create vacuum-free analogs of electronic devices and systems: discrete and analog converters of electrical signals (amplifiers, generators, key elements, memory elements, logic circuits, delay lines, etc.). Optical signal converters – solid-state analogues of electron-optical converters, Vidicon, electron-beam converters (light and image amplifiers, flat transmitting and reproduction screens) information display devices (indicator screens, digital displays and other picture logic devices).