MONOLITHICALLY INTEGRATED THREE ELECTRODE CMUT DEVICE

摘要

A capacitive micromachined ultrasonic transducer (CMUT) cell comprising three electrodes: a first electrode coupled to a cell membrane; a second electrode embedded into a cell floor opposing the first electrode and separated therefrom by a gas or vacuum cavity; and a third electrode opposing the second electrode on the cavity side, wherein a dielectric layer is sandwiched between the second electrode and the third electrode to create a capacitive relation between the second electrode and the third electrode. The three electrode CMUT cell provides an ultrasound transducer with two actively driven (controlled) electrodes.

主权项

1. A capacitive micromachined ultrasonic transducer cell comprising:
a substrate a cell membrane opposing the substrate with a gap there between; a first electrode coupled to the cell membrane, a second electrode embedded into a cell floor opposing the first electrode and separated therefrom by a gas or vacuum cavity, wherein the cell floor comprises an upper surface of the substrate, and a third electrode, and the third electrode, which is located in the cell floor opposing the second electrode from the cavity side, wherein said third electrode is capacitively coupled with the first or second electrode, whereby the capacitive coupling is realized by a dielectric layer sandwiched between and being in direct contact with the capacitively coupled electrodes.