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Journal of Physical Studies 7(3), 344–348 (2003)
DOI: https://doi.org/10.30970/jps.07.344 THE PHYSICAL PHENOMENA IN SEMICONDUCTOR–PIEZOELECTRIC STRUCTURES AND THE OPPORTUNITY OF NEW CLASS DEVICES CREATION ON THEIR BASISYa. I. Lepikh
The Odessa National Mechnikov University, |
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In the article on the basis of the analytical review the results of different authors and our own research the physical phenomena are considered which arise during surface acoustic waves (SAW) generation, distribution and detecting in semiconductor-piezoelectric (S-P) layered structures and effects of varied physical nature fields interaction in them. Such, for example, as transport of charge in quantum heterojunction wells under acoustic field influence, charge carriers autoinjection in p-n junction and from contact, acoustoluminescence and the other. The mechanisms of the physical phenomena are considered also which arise in photo sensitive structures S-P. Owing to the processes of free charge carriers photoexcitation, their diffusion and drift in the electrical field, the capture on traps periodic distribution of a space charge is formed. At certain parameters of a light flow and external electrical field it is possible to reach acousto-EMF generation and signal of convolution of two signals. The optoacoustic interaction and an opportunity of SAW generation control in photosensitive piezosemiconductor-piezoelectric structure with the formed Shottky barrier are considered in detail. As a result of an irradiation such a S-P structure by the modulated light the electron photoemission is realized, the photocurrent arises with the frequency which corresponds to the appropriate modulation frequency that in turn excite SAW with the same frequency. The phototermoacoustic effect in IR range in a structure of photosensitive semiconductor-piezoelectric with the system SAW converters is described too. The physical mechanism of the effect is that at certain ratio of optical and temperature layered structure elements properties at IR irradiation the adequate change SAW speed distribution is achieved. It is essential that the spectral characteristic of such a structure can be formed during its synthesis. It is pointed out that the results are prospective for the of creation of the microelectronic functionally integrated devices. The parameters, achieved in laboratory samples, of some classes of devices show their essential advantage in comparison with the analogues constructed on different physical principles, particularly in connection with an opportunity to control the characteristics.
PACS number(s): 77.65.Dq