Patent ID: 8309428

Claim:
A method of producing an integrated circuit/transducer device having a substrate, a complimentary-metal-oxide-semiconductor (CMOS) circuit located over a CMOS circuit region of the substrate, and a capacitive micromachined ultrasonic transducer (cMUT) located over a cMUT region of the substrate, the method comprising: a) depositing a first layer over both the CMOS circuit region and the cMUT region of the substrate that: i. forms a layer within the CMOS circuit; ii. forms a lower electrode within the cMUT element; b) depositing a dielectric layer over the cMUT region after step a); c) depositing a sacrificial layer over the cMUT region after step b); d) depositing a second layer over both the CMOS circuit region and the cMUT region of the substrate that: i. forms a layer within the CMOS circuit; ii. forms an upper electrode within the cMUT element; e) depositing a protective layer over both the CMOS circuit region and the cMUT region after step d); f) removing the sacrificial layer to form a cavity between the upper electrode and lower electrode of the cMUT after step e); and g) depositing a sealant layer over the cMUT region to seal the cavity after step f).