US 12,486,159 B2
Micro-machined ultrasound transducers with insulation layer and methods of manufacture
Naresh Mantravadi, San Jose, CA (US); Haesung Kwon, Austin, TX (US); and Brian Bircumshaw, Oakland, CA (US)
Assigned to Exo Imaging, Inc., Santa Clara, CA (US)
Filed by Exo Imaging, Inc., Redwood City, CA (US)
Filed on Jun. 30, 2021, as Appl. No. 17/364,381.
Prior Publication US 2023/0002213 A1, Jan. 5, 2023
Int. Cl. B06B 1/06 (2006.01); B06B 1/02 (2006.01); B81B 3/00 (2006.01); B81C 1/00 (2006.01)
CPC B81B 3/0021 (2013.01) [B06B 1/0292 (2013.01); B06B 1/0603 (2013.01); B81C 1/00158 (2013.01); B81B 2201/0271 (2013.01); B81B 2203/0127 (2013.01); B81B 2203/0315 (2013.01); B81B 2207/07 (2013.01); B81C 2201/0132 (2013.01); B81C 2203/036 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A multi-silicon on insulator (SOI) micromachined ultrasonic transducer (MUT) device comprising:
a multi-SOI substrate comprising a first SOI layer and a second SOI layer disposed above the first SOI layer, such that the second SOI layer forms a top surface of the multi-SOI substrate; and
a MUT comprising a membrane and being affixed to the top surface of the multi-SOI substrate,
wherein each of the first SOI layer and the second SOI layer comprises an insulating layer and a semiconducting layer,
wherein the first SOI layer further comprises a cavity and one or more trenches, the cavity being located under the membrane of the MUT and having a first depth, and the one or more trenches being located at least partially around a perimeter of the cavity and having a second depth that at least partially overlaps the first depth within the multi-SOI substrate.