An ultrasonic sensor with a center frequency of 478 MHz is designed using the KLM equivalent circuit model

and the PZT thick film piezoelectric material with thickness of 4 μm is prepared on a silicon substrate by sol-gel method. The crystal structure

surface profile and piezoelectricity of the piezoelectric material are tested.The material is uniform and compact

and the piezoelectric properties are good. The fabrication process of ultrasonic sensor is studied

a high frequency ultrasonic sensor with a working frequency of 459 MHz is made. The test platform is set up to test its electrical impedance

experimental value is matched with theoretical value

the impedance error is 1. 8 %

and the center frequency error is 3. 9 %.