, and prevent
short circuiting caused by the occasional engagement
of the top and bottom electrode; the top of the cavity
is the integration membrane made by SOI top silicon.
When the sensor is operating in water, in order to
avoid the hydrolysis caused by a strong electric field
in the cavity, the vibration must be a vacuum-sealed
cavity. The top and bottom electrodes are deposited
on the membrane and substrate respectively.
Meanwhile, a MEMS capacitive ultrasonic transducer
is composed of many cells which are connected
parallel and distributed in a certain order