Capacitive micromachined ultrasonic transducer arrays for medical imaging: experimental results

Capacitive micromachined ultrasonic transducer (cMUT) arrays provide broad bandwidth, high sensitivity, low mechanical impedance, and potential for electronic integration, and thus are promising for medical imaging applications. We have designed and fabricated 1D and 2D MUT arrays of various sizes using standard integrated circuit fabrication processes. We improved the device parameters for medical imaging applications to achieve fully functional 64- and 128-element linear 1D cMUT arrays. We have also built a computer controlled experimental setup for collecting pulse-echo data from the test phantoms using MUT arrays. In this paper the design and optimization of the immersion cMUTs for medical imaging system are discussed, and the phased array B-scan sector images taken by 1D MUT arrays are presented.