Open AccessModelling and Analysis of Dielectric Charge of CMUTs
Author(s) -
Jucai Li,
Yan Li,
Peiyu Zhang
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/768/6/062106
Subject(s) - materials science , dielectric , ultrasonic sensor , piezoelectricity , silicon nitride , capacitive sensing , diaphragm (acoustics) , optoelectronics , capacitive micromachined ultrasonic transducers , silicon , acoustics , engineering physics , electrical engineering , composite material , engineering , loudspeaker , physics
Capacitive micromechanical ultrasonic transducers ( CMUTs ) have the remarkable advantages that the traditional piezoelectric ultrasonic transducers do not have, and they are expected to replace the traditional piezoelectric ultrasonic transducers as the mainstream product in the market. However, the dielectric charging problem has a great influence on the normal work of CMUT, and it is also one of the main obstacles to its commercialization. In this paper, the influence of dielectric charging is introduced, and then the model of non-contact charging and contact charging is established to analyse the mechanism of charging. The influencing factors of dielectric charging were found out, and the influence of each influencing factor on charging was analysed. The charging of the diaphragm and the insulating layer were compared. The results showed that silicon dioxide is less charged than the silicon nitride. Finally, based on the analysis of non-contact charging and contact charging, a method of changing the shape and coverage area of the insulating layer to reduce dielectric charging is proposed.