NANOSCALE FERROELECTRIC FILM – A NEW ACTIVE MEDIUM FOR MICROELECTRONICS

The results of interdisciplinary studies of ferroelectric heterostructures obtained using a fundamentally new technology developed in the Laboratory of Physics of Thin Ferroelectric Films of the Southern Scientific Centre of the Russian Academy of Sciences (SSC RAS) are presented. The heterostructures of complex oxides obtained by this technology significantly exceed the best foreign samples in terms of structural perfection and dielectric properties. A comprehensive study of the heterostructures of complex oxides (methods of X-ray diffraction analysis, studies of dielectric characteristics, studies of second harmonic generation, raman spectroscopy, high-resolution electron microscopy) allowed us to identify the main features of the use of such a new active medium in microwave microelectronics, optical range, in devices on surface acoustic waves, in micro-sensors, as well as to develop and create prototypes at the SSC RAS. The region of the most optimal film thicknesses for use in microwave control devices is between 25 and 50 nm. This area is characterized by a maximum controllability coefficient and minimal dielectric losses. Moreover, the methods of X-ray diffraction analysis make it possible to unambiguously determine the mechanism of film growth and establish the expected controllability coefficient. A micro-sensor developed at the SSC RAS based on nanoscale ferroelectric heterostructures with a threshold sensitivity of Δl/l ≈ 10−9... 10−10 and operating in the frequency range 10−4... 107 Hz will make it possible to create diagnostic systems for complex mechanical systems in the shortest possible time. It is shown that when using a thin ferroelectric film as an active element in a device on surface acoustic waves, it is possible to double the operating frequency of the converter due to the formation of a periodic domain structure in the film, which is a photonic crystal. By changing the external polarizing voltage on the film electrodes, converters with an electrically adjustable electromechanical coupling coefficient can be created.

thin films, ferroelectric heterostructures, microelectromechanical systems, high-resolution electron microscopy, X-ray diffraction analysis, planar electrodes, Raman scattering, second harmonic generation, phase shifter, microsensor