论文信息 - Optimum design of circular CMUT membranes for high quality factor in air

Optimum design of circular CMUT membranes for high quality factor in air

This paper presents optimum design of circular membrane for high quality factor. A quality factor of CMUT, we designed for resonant chemical sensor, is dominated by Qair and Qsupport. We investigated these two factors independently. We calculate Qair of circular silicon membrane analytically, and numerically. Calculated Qair is compared to measured value. In order to find Qsupport empirically, we measured quality factor of CMUT in vacuum chamber. Qair is proportional to (radius/thickness)-2 and Qsupport is proportional to (radius/thickness)3. Thus the optimum aspect ratio of membrane exists for maximum quality factor.

[1] Hao Zhang,et al. Micromachined acoustic resonant mass sensor , 2005, Journal of Microelectromechanical Systems.

[2] M. Roukes,et al. Ultra-sensitive NEMS-based cantilevers for sensing, scanned probe and very high-frequency applications. , 2007, Nature nanotechnology.

[3] M. M. Fejer,et al. Mechanical Dissipation in Silicon Flexures , 2005, gr-qc/0504134.

[4] Duk-Dong Lee,et al. Fabrication of polymer SAW sensor array to classify chemical warfare agents , 2007 .

[5] F. Ayazi,et al. An analytical model for support loss in micromachined beam resonators with in-plane flexural vibrations , 2003 .

[6] B.T. Khuri-Yakub,et al. Finite-element analysis of capacitive micromachined ultrasonic transducers , 2005, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.