Volumetric imaging using 2D capacitive micromachined ultrasonic transducer arrays (CMUTs): initial results

This paper presents the first volumetric images obtained using a 2D CMUT array with through-wafer via interconnects. An 8×6-element portion of a 32×64-element array flip-chip bonded onto a glass fanout chip was used in the experiments. This study experimentally demonstrates that 2D CMUT arrays can be fabricated with high yield using silicon micromachining processes, individual electrical connections can be provided using through-wafer interconnects, and the flip-chip bonding technique can be used to integrate the dense 2D arrays with electronic circuits for practical imaging applications.