Micromechanical device with elastic assembly having variable elastic constant

Abstract

A micromechanical device includes a semiconductor body, a first mobile structure, an elastic assembly, coupled to the first mobile structure and to the semiconductor body and adapted to undergo deformation in a direction, and at least one abutment element. The elastic assembly is configured to enable an oscillation of the first mobile structure as a function of a force applied thereto. The first mobile structure, the abutment element and the elastic assembly are arranged with respect to one another in such a way that: when the force is lower than a force threshold, the elastic assembly operates with a first elastic constant; and when the force is greater than the threshold force, then the first mobile structure is in contact with the abutment element, and a deformation of the elastic assembly is generated, which operates with a second elastic constant different from the first elastic constant.

1 . A device, comprising:
 a semiconductor body having a surface;   a first mobile mass having a first wall opposite a second wall along a first direction, the first mobile mass having a third wall opposite a fourth wall along a second direction that is transverse to the first direction;   a first elastic assembly extending between the first wall and the second wall of the first mobile mass, the first elastic assembly having a first end coupled to the semiconductor body;   a first electrode extending in the second direction from the first mobile mass;   a second electrode extending in the second direction from the first mobile mass;   a first fixed electrode coupled to the semiconductor body; and   a second fixed electrode coupled to the semiconductor body, the first and second fixed electrodes are spaced from each other and extend from the semiconductor body in a third direction transverse to the first direction and transverse to the second direction, the first electrode of the first mobile mass extending between the first and second fixed electrodes.   
     
     
         2 . The device of  claim 1 , wherein the first mobile mass includes a first internal cavity, the first and second walls of the first mobile mass being in the first internal cavity. 
     
     
         3 . The device of  claim 2 , wherein the first and second electrodes extending into the first internal cavity of the first mobile mass. 
     
     
         4 . The device of  claim 2 , wherein the first elastic assembly is in the first cavity and the first internal cavity includes a first and second recess in the third and fourth walls, respectively, portions of the first elastic assembly extends into the first and second recess. 
     
     
         5 . The device of  claim 1 , wherein the first mobile mass includes a first recess on the third wall and a second recess on the third wall, a second elastic assembly having portions extending into the first and second recess. 
     
     
         6 . The device of  claim 1 , wherein the first elastic assembly has a second end opposite the first end, the second end being coupled to the first mobile mass and being within the first mobile mass. 
     
     
         7 . The device of  claim 1 , wherein the first elastic assembly has a second end opposite the first end, the second end and the first end being within the first and second walls of the first mobile mass. 
     
     
         8 . The device of  claim 7 , wherein the first elastic assembly is within the first mobile mass, the first elastic assembly includes a first extension that extends away from the first electrode. 
     
     
         9 . The device of  claim 1 , wherein the first mobile mass includes a first cavity and a second cavity. 
     
     
         10 . The device of  claim 9 , comprising a second elastic assembly in the second cavity of the first mobile mass, the first elastic assembly being in the first cavity. 
     
     
         11 . A device, comprising:
 a first mobile mass having a plurality of first walls and a plurality of second walls, each first wall of the plurality of first walls being opposite each second wall of the plurality of second walls;   a plurality of first elastic assemblies, each first elastic assembly of the plurality of first elastic assemblies extend between ones of the plurality of the first walls and ones of the plurality of the second walls of the first mobile mass, each of the plurality of first elastic assemblies has a first anchor;   a plurality of first electrodes extending in a first direction from the first mobile mass; and   a first fixed electrode and a second fixed electrode spaced from each other in a second direction that is transverse to the first direction, the first and second fixed electrodes extend in a third direction transverse to the first direction and transverse to the second direction, a first electrode of the plurality of first electrodes extend between the first and second fixed electrodes.   
     
     
         12 . The device of  claim 11  wherein the first mobile mass includes a first internal cavity, the first and second electrodes extending into the first internal cavity. 
     
     
         13 . The device of  claim 11  wherein the first mobile mass includes a first and second internal cavity, the first and second internal cavities are between the first and second electrodes. 
     
     
         14 . The device of  claim 11 , wherein the first mobile mass is between ones of the plurality of first elastic assemblies. 
     
     
         15 . The device of  claim 11 , comprising a first cavity in the first mobile mass, the plurality of first electrodes extending in the first cavity and towards each other. 
     
     
         16 . A micromechanical device, comprising:
 a semiconductor body having a surface;   a first mobile structure having a first inner surface opposite a second inner surface;   a first elastic element extending between the first and second inner surfaces of the first mobile structure, the first elastic assembly extending in a first direction coplanar to the surface of the semiconductor body, the first elastic element having a first end coupled with the semiconductor body;   a second elastic element having a first end coupled with the first mobile structure;   a first electrode extending in the first direction from an outer surface of the first mobile structure;   a first fixed electrode coupled with the semiconductor body; and   a second fixed electrode coupled with the semiconductor body, the first and second fixed electrodes spaced from each other and extending from the semiconductor body in a second direction transverse to the first direction, the first electrode of the first mobile structure extending between the first and second fixed electrodes.   
     
     
         17 . The micromechanical device of  claim 16 , wherein the second elastic element has a second end opposite the first end coupled with the semiconductor body. 
     
     
         18 . The micromechanical device of  claim 16 , comprising a second mobile structure coupled with the first mobile structure by the second elastic element.