Miniature ultrasound acoustic imaging devices using 2-D pMUTs array on epitaxial PZT/SrRuO3/Pt/³-Al2O3/Si structure

In this paper, we demonstrate ultrasound acoustic imaging using a miniature 2-D piezoelectric micromachined ultrasonic transducers (pMUTs) array on an epitaxial PZT/SrRuO₃(SRO)/Pt/γ-Al₂O₃/Si structure for the first time. 2-D pMUTs arrays containing 64 ch (8 × 8 arrays) with 100 μm-diameter circle shape element were fabricated. Detection properties of ultrasonic were measured in water with a ceramics PZT transducer as a point ultrasonic source. The epitaxial structure indicates higher sensitivity than the conventional SiO₂/Si structure. 2-D acoustic images for acrylic targets were successfully observed using pMUTs array, which shows potentials for high resolution 3-D acoustic imaging.