US 11,993,509 B2
MEMS inclinometer having a reduced vibration rectification error
Gabriele Gattere, Castronno (IT); and Francesco Rizzini, Passirano (IT)
Assigned to STMICROELECTRONICS S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on Feb. 18, 2021, as Appl. No. 17/179,157.
Claims priority of application No. 102020000003868 (IT), filed on Feb. 25, 2020.
Prior Publication US 2021/0261403 A1, Aug. 26, 2021
Int. Cl. B81B 3/00 (2006.01); G01P 15/00 (2006.01); G01P 15/08 (2006.01)
CPC B81B 3/0018 (2013.01) [G01P 15/001 (2013.01); B81B 2201/0235 (2013.01); G01P 2015/0862 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A Micro Electro-Mechanical System (MEMS) inclinometer, comprising:
a substrate;
a first mobile mass suspended over the substrate and subject, in use, to an acceleration that depends upon an inclination of the inclinometer; and
a first sensing unit including:
a second mobile mass, suspended over the substrate;
a plurality of elastic elements, each of which is mechanically interposed between the second mobile mass and the substrate and is compliant in a direction parallel to a first axis;
a plurality of elastic structures coupling the first and second mobile masses compliant in the direction parallel to the first axis and to a second axis;
at least one first fixed electrode that is fixed with respect to the substrate; and
at least one first mobile electrode that is fixed with respect to the second mobile mass and configured to form a first variable capacitor with said first fixed electrode,
wherein each elastic structure includes at least one respective elongated structure, which, in resting conditions, extends in a direction parallel to a third axis and, in a plane parallel to a plane containing the first axis and the second axis, has main axes of inertia which are transverse with respect to the first and second axes, so that movements of the first mobile mass in a direction parallel to the second axis, caused by said acceleration, cause corresponding movements of the second mobile mass in a direction parallel to the first axis.