High power piezoelectric characteristics of KNbO3 thick films by hydrothermal method

Very high intensity and high frequency ultrasonic transducer using hydrothermal KNbO
₃
thick film was developed. The vibration velocity of surface of KNbO
₃
thick film was measured with thickness vibration mode. The amplitude of vibration velocity was 2.5m/s or over. And the radiation sound-pressure from the prototype ultrasonic transducer was measured at resonance frequency in degassed water. The radiation ultrasound was 4MPa or over.