3-D real-time volumetric imaging using 20 MHz 1.5-mm diameter single-chip CMUT-on-CMOS array

An intravascular ultrasound (IVUS) catheter that can provide forward-viewing volumetric ultrasound images would be an invaluable clinical tool for guiding interventions in coronary arteries for treatment of chronic total occlusions (CTOs) and for helping stent deployment. Single-chip integration of front-end electronics with CMUTs is highly desirable for reduced interconnect complexity, miniaturization, and flexibility of IVUS catheters. For this purpose we use the monolithic CMUT-onCMOS integration where CMUTs are fabricated directly on top of pre-processed CMOS wafers. We have previously demonstrated the characterization and imaging performance of monolithically integrated single-chip CMUT-on-CMOS Forward looking IVUS array. Here, we present 3-D real-time volumetric imaging results on vessel mimicking and relevant biological phantoms. The fabricated single chip CMUT-on-CMOS device has 56 transmit and 48 receive array elements operating at 20 MHz with a fractional bandwidth of 50%. The imaging results demonstrate that the single-chip forward looking IVUS (FLIVUS) system with monolithically integrated electronics has potential to visualize the front view of coronary arteries.