Patent ID: 8716816
Filing Date: 2014-05-06
Classification: H01L

Abstract:
1. A capacitive micromachined ultrasonic transducer (CMUT) device, comprising: a wafer having at least a first semi-conductor electrode layer on an insulating dielectric; the first semi-conductor electrode layer forming a CMUT pattern with dielectric stand-offs on the first semi-conductor electrode layer, the dielectric stand-offs being continuous in at least selected portions of the CMUT pattern to define sealed CMUT cavities; a second semi-conductor electrode layer bonded onto the dielectric stand-offs with a gap between the first semi-conductor electrode layer and the second semi-conductor electrode layer creating the sealed CMUT cavities, the second semi-condutor electrode layer comprising a mechanical membrane responsive to an electrical stimulus to generate an ultrasonic signal and responsive to sound waves to change capacitance; the dielectric stand-offs having a height sufficient to provide electrical isolation between the first semi-conductor electrode layer and the second semi-conductor electrode layer; and for each CMUT in the CMUT pattern, respective contacts on the first semi-conductor electrode layer and the second semi-conductor electrode layer.