1. “A New Regime for Operating CMUTs” (2003)
2. “A Comparison Between Conventional and Collapse-Mode Capacitive Micromachined Ultrasonic Transducers in 10 MHz 1-D Arrays” (2013)
3. “Experimental Characterization of Collapse-Mode CMUT Operation” (2006)
4. “Capacitive Micromachined Ultrasound Transducers for Transmitting and Receiving Ultrasound in Air” (2019)

“A New Regime for Operating CMUTs” (2003)

MEMBRANE MOVEMENT DIAGRAM

membrane shape: position of the bottom surface of the CMUT membrane at each radial distance from the center to the membrane rim

→ membrane height extends from 0.1 um to 1.1 um (position of nondeformed membrane)

→ dash-dot line shows membrane collapsing with membrane in contact with bottom layer with radius of 20 um (140V)

→ dot line shows reducing voltage below collapse voltage (68.2V)

DISUCSSION

⇒ dash-dot and dot both show the range of deformed membrane

movement of membrane can be seen despite being collapsed (volumetric change of 19%, compared to that of conventional at 11%)

CAPACITANCE ⇒ indicator of electromechanical efficiency

static capacitance vs Vdc relationship of CMUT is shown