The effect of the conductivity of a film located near a piezoelectric resonator with a lateral electric field based on the PZT ceramics on its characteristics

• Published in: Ultrasonics 2019-04, Vol.94, p.169-173
• Main Authors: Zaitsev, B.D., Semyonov, A.P., Teplykh, A.A., Borodina, I.A.
• Format: Article
• Language: English
• Subjects: Conductive films; Electrical boundary conditions; Finite element analysis; Gas sensitive films; Parallel resonant frequency; Piezoelectric resonator with lateral electric field; PZT ceramics; Real part of the electrical impedance
• ISSN: 0041-624X; 1874-9968
• DOI: 10.1016/j.ultras.2018.09.016

•Effect of a conducting film set near PZT lateral electric field resonator is studied.•Film conductivity change affects the resonant frequency in certain conductivity range.•Film conductivity change affects maximum value of real part of electrical impedance.•Pointed change of maximum value of real part of electrical impedance may achieve 57%.•Results are useful for developing a gas sensors based on PZT piezoelectric resonators. In this paper, we investigated theoretically and experimentally the effect of the conductivity of the film located in the immediate vicinity of the free side of a piezoelectric resonator based on the PZT ceramics on its characteristics. It is shown that with increasing the conductivity of the film at first the parallel resonant frequency does not change, then it decreases in a certain interval and after that remains practically constant. With increasing the width of the gap between the film and the resonator, the resonant frequency increases and reaches the saturation. At that the degree of the total frequency change decreases with decreasing the conductivity of the film. We also investigated the dependence of the maximum value of the real part of the electrical impedance on the film conductivity at the different values of the width of the gap between the film and the resonator. The dependences of the maximum value of the real part of the electrical impedance on the width of the gap between the film and the resonator are also obtained for different values of the film conductivity. A comparison of the theoretical and experimental data showed their good qualitative agreement.