| abstract |
PROBLEM TO BE SOLVED: To provide a capacitive ultrasonic transducer driven only by an RF pulse signal without using a DC voltage. A membrane comprising a low-resistance silicon single crystal substrate and a silicon compound, a first electrode disposed on the low-resistance silicon single crystal substrate, and a membrane supporting the second electrode disposed with a gap therebetween, In a capacitive ultrasonic transducer that vibrates at a high frequency by applying a voltage between the electrodes and transmits and receives ultrasonic waves, the dielectric film 9 is electretized by corona discharge treatment, and the dielectric film 9 is By charging the battery, the above-mentioned problems are solved. [Selection] Figure 1 |