US 12,336,432 B2
Micro electro mechanical system and manufacturing method thereof
Gianluca Longoni, Cernusco sul Naviglio (IT); and Luca Seghizzi, Milan (IT)
Assigned to STMICROELECTRONICS S.r.l., Agrate Brianza (IT)
Filed by STMICROELECTRONICS S.r.l., Agrate Brianza (IT)
Filed on Dec. 11, 2023, as Appl. No. 18/535,923.
Application 18/535,923 is a division of application No. 17/181,432, filed on Feb. 22, 2021, granted, now 11,889,765.
Claims priority of application No. 102020000003967 (IT), filed on Feb. 26, 2020.
Prior Publication US 2024/0130240 A1, Apr. 18, 2024
Int. Cl. H10N 30/20 (2023.01); B81B 3/00 (2006.01); H02N 2/18 (2006.01); H10N 30/00 (2023.01); H10N 30/05 (2023.01); H10N 30/074 (2023.01)
CPC H10N 30/2042 (2023.02) [B81B 3/0021 (2013.01); H02N 2/186 (2013.01); H10N 30/05 (2023.02); H10N 30/074 (2023.02); H10N 30/706 (2024.05); B81B 2203/0118 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method for manufacturing a MEMS device, comprising:
forming at least one cantilevered member protruding from a side surface of a semiconductor substrate, the semiconductor substrate including a main surface extending perpendicular to a first direction and a side surface extending on a plane parallel to the first direction and to a second direction, the second direction being perpendicular to the first direction, the at least one cantilevered member protruding from the side surface along a third direction perpendicular to the first and second directions, forming the at least one cantilevered member comprises:
forming oxide portions on a starting semiconductor substrate having a first surface, the oxide portions being raised with respect to the first surface along the first direction, and being spaced apart to each other along the second direction;
forming semiconductor portions on portions of exposed surfaces of the oxide portions to define an alternating sequence of recesses and semiconductor portions, each semiconductor portion being astride two oxide portions and defining a corresponding cavity with the two oxide portions, each recess having a bottom surface corresponding to an exposed surface portion of an oxide portion and side surfaces corresponding to side surfaces of two semiconductor portions;
filling the recesses with a piezoelectric material, the filling the recesses with the piezoelectric material includes filling the recesses with the piezoelectric material having a crystalline orientation perpendicular to the first direction; and
forming the at least one cantilevered member by opening vias in the semiconductor portions along the first direction until reaching the cavities;
wherein the at least one cantilevered member comprises a body portion including a piezoelectric material, the body portion having a length along the third direction, a height along the first direction and a width along the second direction, the height being greater than the width, the at least one cantilevered member being configured to vibrate by lateral bending along a direction perpendicular to the first direction.