Persons

The influence of the excess holes capture efficiency on the carrier collection process with an increasing photoexcitation in quantum wells of n -AlGaAs/GaAs heterostructures has been studied. It has been shown that the influence of the ratio of photoluminescence intensities from quantum well and from barrier layers on the quantum well width has an oscillating form. The hole capture times in the maximum and the minimum of the oscillations have been estimated (3 psec and 370 psec, respectively). The energy transition shift in resonant quantum well at high excitation densities has been explained by the «charge buildup effect» due to the difference between the capture efficiencies of the electrons and holes.

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The development of the devices based on gallium nitride has become the priority direction, reflecting the world trends in the development of the microwave electronics. The use of the nanoheterostructures based on GaN for creating monolithic integrated circuits (MIC) makes it possible to realize the systems operating in a significantly wider range of temperatures, with a higher specific output power and efficiency as compared to the devices based on silicon and gallium arsenide. On the basis of nitride heterostructures a set of MMIC, intended for application in the receiver-transmitter modules with rigid restrictions for the mass-dimensional characteristics and power consumption, and the increased requirements for the resistance to the external and special factors, and operating in the frequency range of 57-64 GHz has been developed. The technical and operational characteristics of the specified products have been presented. The developed MIC can be used in harsh operating conditions. A brief description of the technological route and of the developed original design and technological solutions has been given. A sample of a single-chip transmitter-receiver module, capable of replacing the equipment 4-5 crystals of single-function MIC of the previous generation has been presented. The technology of forming nanoheterostructurs based on GaN permits to manufacture amplifiers MIC with high power and low noise coefficient, to integrate all components of the receiver-transmitter module on a single crystal.

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