Grant: Strategic Projects Supplemental Competition

Ultrasound imaging accounts for almost 25% of all clinical imaging methods, with two strategic directions in sight: fabrication of low-cost, portable equipment, easy to deploy in remote areas and help in tele-diagnostic, and, on the high-end site, the design of high resolution 3D and 4D (i.e. real time 3D) acoustic imaging systems, which need 2D arrays with a large number of transducers for generating and receiving ultrasonic waves. While present piezoelectric transducers are commonly used as front-end for ultrasonic imaging systems, the lack of chip-level integration with electronics and the relatively high cost are obstacles hindering both evolution directions. Taking advantage of the potential of newly existing CMOS-MEMS integrated technologies, the present proposal targets the development of a medical imaging system using as front-end an array of capacitive micromachined ultrasonic transducers (CMUTs), integrated at chip level with CMOS electronics. MEMS (Microelectromechanical Systems) technology makes possible the fabrication of ultrasonic sensors that can operate at higher frequencies than most piezoelectric devices, with a wide bandwidth and large dynamic range. On a short-term, within the duration of the project, the goal is to design and test a linear CMUT array integrated with electronic circuitry and to interface it to existing ultrasound equipment; a second design iteration will target a 2D integrated CMUT array. A longer-term goal is to design an ultrasound imaging system suitable for 3D and 4D, using 2D CMUT arrays interfaced with real-time signal processing and control algorithms implemented in reconfigurable hardware (FPGA). A main aplication target is a low-cost, high performance portable ultrasonic system for breast cancer diagnostic and monitoring the evolution of the tumor in conjunction with neo-adjuvant chemotherapy. The emerging CMUT-based imaging technology is a new cross-disciplinary field, that will set the stage for the implementation of advanced information processing systems in the field of MHz-range ultrasound imaging.