Electrode arrangement for a pMUT and pMUT transducer array

A piezoelectric micro-machined ultrasonic transducer (pMUT) comprising:

• a first electrode having a first electrode portion and a second electrode portion, the second electrode portion being separately operable from the first electrode portion, wherein, the first electrode portion is symmetric with the second electrode portion;
• a second electrode spaced apart from the first electrode and defining a space between the first electrode and the second electrode;
• a silicon passive membrane layer disposed under the second electrode;
• and
• a piezoelectric material disposed in the space,
• wherein the first electrode is circular, and the first electrode portion comprises a first semi-circular portion of the electrode and a first semi-annular portion of the electrode and the second electrode portion comprises a second semi-circular portion of the electrode and a second semi-annular portion of the electrode.