Thin-film ZnO ultrasonic transducers for tissue characterization

Abstract

Thin-film ZnO ultrasonic transducers for operation at 140 MHz mounted in a rod-shaped probe were fabricated and evaluated for use in tissue characterization. Highly oriented ZnO films 12.5-/spl mu/m thick were successfully grown for use as transducers having sufficient sensitivity to detect small ultrasound signals inside living samples. The ZnO transducer was mounted in the rod-shaped probe which could rotate mechanically around its axis and shift along the axis. Using this scanning, tissue images were formed in the C-scan mode in a cylindrical plane within the tissue. Preliminary bovine kidney images demonstrate the feasibility of tissue imaging using the miniature, high-frequency transducers mounted in the rod-shaped probe.