5F-4 Design and Experimental Characterization of a Dual-Electrode CMUT Array for Intra-Cardiac Ultrasound Imaging

A 1-D dual-electrode CMUT array for intracardiac echocardiography with a center frequency of 8 MHz has been designed and fabricated. Total transduction performance increase of 15.7dB is obtained (9dB in receive, 6.7dB in transmit) by using dual electrode configuration making CMUTs more competitive with piezoelectric transducers for a wide range of applications. This improvement is verified both with experiments and simulations. A net peak output pressure of 1.6MPa on the dual-electrode membrane with tone burst excitation at 12MHz is reported. In addition, dynamic biasing is demonstrated to increase the dual electrode CMUT performance. Finally the comparison of dual electrode and conventional CMUT is demonstrated with tissue mimicking phantom. Dual electrode CMUT showed 13dB more SNR even though the electrode size was optimized for conventional configuration.