Fig. 5: Characterization of our fabricated CMUT chips.
From: Noninvasive fluid bubble detection based on capacitive micromachined ultrasonic transducers
a Main fabrication process of the CMUTs. b Structural schematic of the CMUTs. i) Cross section of a CMUT cell. ii) Optical microscope image of the CMUT array. c CMUT bandwidth measured at a distance of 15 mm. d Transmitting acoustic pressure of our CMUT chip on its axis. e The received voltage variation of the CMUT chip with varying frequencies
