US 11,865,581 B2
Ultrasonic MEMS acoustic transducer with reduced stress sensitivity and manufacturing process thereof
Gabriele Gattere, Castronno (IT); Carlo Valzasina, Gessate (IT); Federico Vercesi, Milan (IT); and Giorgio Allegato, Monza (IT)
Assigned to STMICROELECTRONICS S.R.L., Agrate Brianza (IT)
Filed by STMICROELECTRONICS S.R.L., Agrate Brianza (IT)
Filed on Nov. 14, 2019, as Appl. No. 16/684,289.
Claims priority of application No. 102018000010485 (IT), filed on Nov. 21, 2018.
Prior Publication US 2020/0156114 A1, May 21, 2020
Int. Cl. B06B 1/06 (2006.01); B81B 7/00 (2006.01); B81C 1/00 (2006.01)
CPC B06B 1/0681 (2013.01) [B06B 1/0666 (2013.01); B81B 7/0016 (2013.01); B81C 1/00825 (2013.01); B81B 2201/0264 (2013.01); B81B 2201/0271 (2013.01); B81B 2203/0127 (2013.01); B81B 2203/0163 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A MEMS acoustic transducer of an ultrasonic type, comprising:
a body of semiconductor material, the body having first and second surfaces opposite to each other;
a first cavity in the body;
a sensitive portion suspended in the first cavity and extending between the first cavity and the first surface of the body, the sensitive portion including a second central cavity and a membrane extending between the second central cavity and the first surface of the body; and
an elastic supporting structure coupling the sensitive portion to the body, the elastic supporting structure being suspended in the first cavity.