Kotel'nikov Institute of Radio Engineering and Electronics of RAS, Saratov Branch, Saratov 410019, Russia.
Kotel'nikov Institute of Radio Engineering and Electronics of RAS, Saratov Branch, Saratov 410019, Russia.
Ultrasonics. 2019 Nov;99:105973. doi: 10.1016/j.ultras.2019.105973. Epub 2019 Aug 1.
Theoretical and experimental studies of the influence of a thin metal film on the characteristics of a piezoelectric resonator with a lateral electric field showed the possibility of creating a micro-displacement meter in the range of 10-300 μm. For the experiments, two resonators based on the plates of PZT piezoceramics with a thickness of 3.56 and 4.46 mm with resonant frequencies of ~96 and ~260 kHz for both resonators were used. It has been experimentally established that in both cases, with an increase in the width of the gap between the free side of the piezoelectric resonator and thin aluminum film, the frequency of the parallel resonance and maximum value of the real part of the electrical impedance increase and reach saturation. Besides, it has been shown that the relative change of these values with a change in the width of the gap in the range 10-300 μm increases with decreasing the thickness of the resonator. In this case, the frequency of the series resonance practically does not change. It has been also established that the sensitivity of the resonator to the presence of a conducting film at the resonant frequency of ~96 kHz is significantly higher in comparison with the resonant frequency of ~260 kHz. The experimental results are in the qualitative agreement with the theoretical data.
理论和实验研究了薄金属膜对具有横向电场的压电谐振器特性的影响，结果表明有可能在 10-300μm 的范围内制造微位移计。对于实验，使用了两块基于厚度为 3.56 和 4.46mm 的 PZT 压电陶瓷板的谐振器，两个谐振器的谐振频率约为 96 和 260kHz。实验结果表明，在这两种情况下，随着压电谐振器自由侧与薄铝膜之间的间隙宽度的增加，并联谐振频率和实部电阻抗的最大值增加并达到饱和。此外，还表明，随着间隙宽度在 10-300μm 的范围内变化，这些值的相对变化随着谐振器厚度的减小而增加。在这种情况下，串联谐振频率实际上没有变化。还确定，与约 260kHz 的谐振频率相比，在约 96kHz 的谐振频率下，谐振器对存在导电膜的灵敏度明显更高。实验结果与理论数据定性一致。
