Fully Integrated Electronic-Photonic Ultrasound Receiver Array for Endoscopic Imaging Applications in a Zero-Change 45nm CMOS-SOI Process

This paper presents the first fully integrated 2-D array of electronic-photonic ultrasound sensors targeting low-power miniaturized ultrasound probes for endoscopic applications. Fabricated in a zero-change 45nm CMOS-SOI technology this Electronic-Photonic System on Chip (EPSoC), utilizes micro-ring resonators (MRRs) as ultrasound sensors instead of the traditional piezoelectric or capacitive micromachined transducers (PMUTs or CMUTs). The photonic nature of the sensor enables remoting the power-hungry receive electronics outside the probe tip, lowering the power dissipation inside the human body, eliminates the electrical cabling and reduces fiber count by 4x using wavelength division multiplexed (WDM) MRR sensors coupled onto the same waveguide. The photonic sensing element demonstrates >30 MHz bandwidth, and 7.3 mV/kPa sensitivity, while consuming 0.43 mW of power.