Development of temperature stable acoustic line based on piezoelectric plate and nanocomposite polymeric film

Abstract

As is well known the development of high effective and thermostable acoustic devices assuming use of the acoustic waves with high coefficient of electromechanical coupling (K2) and low temperature coefficient of delay (TCD) is very important. At present there exist the papers showing that fundamental shear-horizontal (SH0) acoustic waves in thin (in comparison with wavelength) piezoelectric plates possess significantly more electromechanical coupling coefficient than surface acoustic waves (SAW). However, although the value of TCD of such waves is equal 66 ppm/C that is some less than for SAW but this is not enough for development of temperature stable devices. In this paper the theoretical analysis of temperature influence on velocity of SH0 wave in YX lithium niobate plate, which contacts by one side with nanocomposite polymeric films with various concentrations of Fe nanoparticles has been carried out. Calculation has shown that there exist such concentrations of Fe nanoparticles when the TCD of SH0 wave in aforementioned structure is equal 15 ppm/C. In whole the obtained results open the real prospective of use of SH0 wave in structures based on thin piezoelectric plates for development of temperature stable acoustic devices for signal processing and high sensitive sensors.