Micromachined Transducers
Capacitative micromachined Ultrasonic transducers, manufactured using standard semiconductor fabrication techniques have received a lot of interest over recent years. Working in collaboration with Qinetiq we have a number projects in this area, working with devices using standard CMOS processes. These devices vary in dimension from 0.100-5mm area, somewhat larger than those reported elsewhere, with membrane thickness from 0.5-2µm.
![Schematic of transducer.](cmutschem.gif)
![SEM image of Transducer](cmutsem.gif)
Current research is concerned characterising arrays of devices machined on the same substrate for use as as passive 2-D arrays for imaging, active 1-D phased arrays and as apodised imersion transducers..
![Photograph of micromachined array](cmutarray.gif)
![Scanned image of 20p coin](arraycoin.gif)
Related Paper
R.A. Noble, A.R.D. Jones, T.J. Robertson, D.A. Hutchins and D.R. Billson, "Novel wide bandwidth micromachined ultrasonic transducers", IEEE Trans. Ultras. Ferr. Freq. Contr. 48, 1495-1507 (2001)