Lukacs M, Sayer M, Foster S
Department of Physics, Queen's University, Kingston, Ontario, Canada, K7L 3N6.
IEEE Trans Ultrason Ferroelectr Freq Control. 2000;47(1):148-59. doi: 10.1109/58.818757.
A sol gel composite process has been used to produce lead zirconate titanate coatings in the thickness range of 3 to 100 microm on aluminum substrates. The complex permittivity (epsilon(33)(S )), elastic stiffness (c(33)(D)), and the piezoelectric constant (h(33)) of the coating and the complex elastic stiffness (c(33)(D)) of the substrate have been determined using impedance measurements and a commercially available software program [Piezoelectric Resonance Analysis Program PRAP 2.0, TASI Technical Software, Kingston, Ontario, Canada]. The complex components of the material parameters account for the losses within the film and the substrate. Sol gel composite films on aluminum have a dielectric constant of 220 with an imaginary component of 1% and an electromechanical coupling coefficient of up to 0.24 with an imaginary component of 3%. These films are applied to the fabrication of a high frequency transducers suitable for ultrasound biomicroscopy (UBM). By combining the sol gel composite material with existing transducer fabrication techniques, single-element focusing transducers have been produced that operate in the frequency range of 70 to 160 MHz. Devices have -6-dB bandwidths up to 52% and minimum insertion losses ranging from -47 to -58 dB. Real-time images of phantom materials and ex vivo biological samples are shown.
一种溶胶-凝胶复合工艺已被用于在铝基板上制备厚度范围为3至100微米的锆钛酸铅涂层。利用阻抗测量和一款商用软件程序[压电共振分析程序PRAP 2.0，TASI技术软件，加拿大安大略省金斯敦]测定了涂层的复介电常数（ε(33)(S)）、弹性刚度（c(33)(D)）和压电常数（h(33)）以及基板的复弹性刚度（c(33)(D)）。材料参数的复数分量考虑了薄膜和基板内部的损耗。铝上的溶胶-凝胶复合薄膜的介电常数为220，虚部为1%，机电耦合系数高达0.24，虚部为3%。这些薄膜被应用于制造适用于超声生物显微镜（UBM）的高频换能器。通过将溶胶-凝胶复合材料与现有的换能器制造技术相结合，已生产出在70至160 MHz频率范围内工作的单元素聚焦换能器。器件的-6 dB带宽高达52%，最小插入损耗在-47至-58 dB之间。展示了模拟材料和离体生物样品的实时图像。
