Capacitive micromachined ultrasonic transducersresearch d
(CMUT) is an important research direction of MEMS
technology, its acoustic impedance is close to gas and
liquid, thus a matching layer is not needed; [4-5] It
also has good mechanical and electrical properties
and higher resonance frequencies (up to tens of MHz)
and a quality factor (up to several hundred); all of
these good properties make it possible to achieve
high sensitivity and small-scale pressure
measurements. Meanwhile, it has such advantages as:
simple structure, low cost