US 12,066,621 B2
MEMS device with tiltable structure and improved control
Roberto Carminati, Piancogno (IT); Nicolo' Boni, Albino (IT); Andrea Barbieri, Casalpusterlengo (IT); Marco Zamprogno, Cesano Maderno (IT); and Luca Molinari, Piacenza (IT)
Assigned to STMicroelectron S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on Apr. 14, 2022, as Appl. No. 17/720,506.
Claims priority of application No. 102021000009635 (IT), filed on Apr. 16, 2021.
Prior Publication US 2022/0334378 A1, Oct. 20, 2022
Int. Cl. G02B 26/08 (2006.01); H02N 2/02 (2006.01); H02N 2/06 (2006.01)
CPC G02B 26/0858 (2013.01) [H02N 2/028 (2013.01); H02N 2/062 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A MEMS device, comprising:
a semiconductor body defining a cavity and forming an anchor portion;
a tiltable structure elastically suspended over the cavity;
first and second support arms extending along a rotation axis of the tiltable structure between the anchor portion and opposite sides of the tiltable structure; and
first and second piezoelectric actuation structures facing opposite sides of the first support arm and extending between the anchor portion and part of the MEMS device, wherein said first and second piezoelectric actuation structures are biasable to deform mechanically, thereby generating a rotation of the tiltable structure around the rotation axis;
wherein the first and second piezoelectric actuation structures carry first and second displacement sensors of piezoelectric type and being opposite to each other with respect to the rotation axis;
wherein, when the tiltable structure rotates around the rotation axis due to actuation of the first and second piezoelectric actuation structures, the first and second displacement sensors are subject to respective mechanical deformations and generate first and second sensing signals in phase opposition to each other and being indicative of the rotation of the tiltable structure around the rotation axis; and
wherein the first and second sensing signals are configured to be acquired in a differential manner.