Yashvanth Varshitha, Chowdhury Sazzadur
Electrical and Computer Engineering Department, University of Windsor, Windsor, ON N9B 3P4, Canada.
Sensors (Basel). 2021 Feb 19;21(4):1459. doi: 10.3390/s21041459.
This paper presents a novel technique to reduce acoustic crosstalk in capacitive micromachined ultrasonic transducer (CMUT) arrays. The technique involves fabricating a thin layer of diisocyanate enhanced silica aerogel on the top surface of a CMUT array. The silica aerogel layer introduces a highly nanoporous permeable layer to reduce the intensity of the Scholte wave at the CMUT-fluid interface. 3D finite element analysis (FEA) simulation in COMSOL shows that the developed technique can provide a 31.5% improvement in crosstalk reduction for the first neighboring element in a 7.5 MHz CMUT array. The average improvement of crosstalk level over the -6 dB fractional bandwidth was 22.1%, which is approximately 5 dB lower than that without an aerogel layer. The results are in excellent agreement with published experimental results to validate the efficacy of the new technique.
本文提出了一种减少电容式微机械超声换能器（CMUT）阵列中声学串扰的新技术。该技术包括在CMUT阵列的顶表面上制造一层二异氰酸酯增强的二氧化硅气凝胶薄层。二氧化硅气凝胶层引入了一个高度纳米多孔的渗透层，以降低CMUT-流体界面处的肖尔特波强度。COMSOL中的三维有限元分析（FEA）模拟表明，所开发的技术可以使7.5 MHz的CMUT阵列中相邻第一个元件的串扰降低31.5%。在-6 dB分数带宽上，串扰水平的平均改善为22.1%，比没有气凝胶层时大约低5 dB。结果与已发表的实验结果高度吻合，验证了新技术的有效性。
