Characteristics of thin film piezoelectric ultrasonic transducer array by chemical solution deposition

In this paper, thin film piezoelectric ultrasonic transducers with a two electrode design and various different membrane sizes were manufactured and characterized. The transducers were fabricated on a silicon wafer by chemical solution deposition (CSD) where PZT was deposited with a total thickness of ~2 ¿m. Afterwards, cavities were wet etched underneath the piezoelectric layer creating bending membranes with a total thickness of ~13 ¿m and cavity sizes from 0.056 mm² to 0.181 mm². Then the transducers were poled and their electromechanical properties were measured with laser vibrometer. The membranes resonance frequencies and quality factors were measured at ~780-2000 kHz and 70-135, respectively, and effective d₃₃ coefficients from 100-290 nm/V.