High-sensitivity, z-axis micro-electro-mechanical detection structure, in particular for an MEMS accelerometer

摘要

A z-axis micro-electro-mechanical detection structure, having a substrate defining a plane and a suspended mass carried by two anchorage elements. The suspended mass includes a translating mass, suspended over the substrate, mobile in a transverse direction to the plane and arranged between the anchorage elements and two tilting masses, each of which is supported by the anchorage elements through respective elastic anchorage elements so as to be able to rotate with respect to respective oscillation axes. The oscillation axes are parallel to each other to enable a translation movement of the translating mass. Fixed electrodes face at a distance the tilting masses or the translating mass so as to be able to detect displacement of the suspended mass as a result of external forces. Elastic supporting elements are arranged between the translating mass and the tilting masses to enable relative rotation between the translating mass and the tilting masses.

主权项

1. A micro-electro-mechanical detection structure, comprising:
a substrate having a first surface in a plane; a first anchorage element and a second anchorage element projecting from and fixed with respect to the substrate; a translating mass suspended over the substrate and moveable in a first direction that is transverse to the plane; first and second elastic anchorage elements; a first tilting mass coupled to the first anchorage element by the first elastic anchorage element, the first tilting mass including a first supporting mass and a first supporting arm, the supporting mass facing a first side of the translating mass, the first supporting arm facing at least a second side of the translating mass, the first mass being configured to rotate with respect to a first axis; a second tilting mass coupled to the second anchorage element by the second elastic anchorage element, the second tilting mass including a second supporting mass and a second supporting arm, the second supporting mass facing a third side of the translating mass, the second supporting arm facing at least a fourth side of the translating mass, the second mass being configured to rotate with respect to a second axis, the first and second axes being substantially parallel to each other; a fixed electrode facing at a distance at least one of the first and second tilting masses and the translating mass; and elastic supporting elements elastically coupling the translating mass to the first and second tilting masses, respectively.