Improved performance of cMUT with nonuniform membranes
Please cite this item using this persistent URLhttp://hdl.handle.net/11693/27311
Proceedings - IEEE Ultrasonics Symposium
- Conference Paper 
When capacitive micromachined ultrasonic transducers are immersed in water, the bandwidth of the device is limited by the membrane's second resonance frequency. At this frequency no mechanical power to immersion medium can be transferred. We present a membrane shape to shift the second resonance frequency to a higher value. The structure consists of a very thin membrane at the outer rim with a rigid mass at the center. The stiffness of the central region moves the second resonance to a higher frequency. This membrane configuration is shown to work better in terms of gain and bandwidth as compared to conventional uniform membranes in both transmission and reception. © 2005 IEEE.