Micromechanical sensor device

• US 9,650,236 B2
• Filed: 06/23/2015
• Issued: 05/16/2017
• Est. Priority Date: 06/26/2014
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Classen, Johannes
• Primary Examiner(s): Toledo, Fernando L
• Assistant Examiner(s): PRASAD, NEIL R
• Application Number:
  US14/747,052
• Publication Number:
  US 20150375990A1
• Time in Patent Office: 693 Days
• CPC Class Codes: B81B 2207/017 Smart-MEMS not provided for in B81B2207/012 - B81B2207/015
• CPC Class Codes: B81B 3/0051 For defining the movement, i.e. structures that guide or limit the movement of an element mechanical arrangements for preventing or damping vibration or shock H01H3/60
• CPC Class Codes: H01L 2224/83805 involving forming a eutectic alloy at the bonding interface

Abstract

A micromechanical sensor device includes: a MEMS element; an ASIC element; a bonding structure provided between the MEMS element and the ASIC element; a layer assemblage having insulating layers and functional layers disposed alternatingly on one another; a sensing element movable in a sensing direction provided in at least one of the functional layers; a spacing element for providing a defined spacing between the MEMS element and the ASIC element being provided by way of a further functional layer; an abutment element having the spacing element and a first bonding layer being disposed on the sensing element; and an insulating layer being disposed on the ASIC element in an abutment region of the abutment element.

Claims

1. A micromechanical sensor device, comprising:

a MEMS element;

an ASIC element;

a bonding layer provided between the MEMS element and the ASIC element;

a layer assemblage having at least one insulating layer and at least one functional layer disposed alternatingly on one another, wherein a sensing element movable in a sensing direction is provided in the at least one functional layer;

a spacing element for providing a defined spacing between the MEMS element and the ASIC element, wherein the spacing element is provided in a further functional layer; and

an abutment element comprising a first portion of the spacing element and a first portion of the bonding layer is formed on the sensing element so that the abutment element moves in the sensing direction along with the sensing element whenever the sensing element moves in the sensing direction,

wherein an insulating layer is disposed on the ASIC element in an abutment region of the abutment element,

wherein the first portion of the bonding layer has an abutment surface facing the ASIC element,

wherein the insulating layer has a surface facing the MEMS element, and

wherein, when the sensing element deflects to a maximum deflection, the abutment surface of the first portion of the bonding layer contacts the surface of the insulating layer facing the MEMS element.

2. The micromechanical sensor device recited in claim 1, wherein the sensing element has a portion provided orthogonally to the sensing direction, and wherein the abutment element is formed on the portion of the sensing element that is orthogonal to the sensing direction.

3. The micromechanical sensor device as recited in claim 2, further comprising:

at least one electrode interacting with the sensing element.

4. The micromechanical sensor device as recited in claim 3, wherein a spacing of the abutment element with respect to the ASIC element is larger than a detection gap with respect to the electrode.

5. The micromechanical sensor device as recited in claim 3, wherein the spacing element has a polysilicon layer.

6. The micromechanical sensor device as recited in claim 3, wherein the bonding layer is one of germanium, aluminum, or metal.

7. The micromechanical sensor device as recited in claim 3, wherein the insulating layer is an oxide material.

8. The micromechanical sensor device as recited in claim 3, wherein the sensing element is provided in a single functional layer.

11. The micromechanical sensor device as recited in claim 1, further comprising:

a bonding structure that electrically connects the ASIC element and the MEMS element, wherein bonding structure is a eutectic mixture of a second portion of the bonding layer and a metal layer of the ASIC element.

9. A method for manufacturing a micromechanical sensor device, comprising:

providing a MEMS element;

providing an ASIC element;

providing a sensing element in the MEMS element, wherein the sensing element is movable in a sensing direction;

providing a bonding layer between the MEMS element and the ASIC element;

providing an abutment element comprising a first portion of the spacing element and a first portion of the bonding layer,

wherein the abutment element is formed on the sensing element so that the abutment element moves in the sensing direction along with the sensing element whenever the sensing element moves in the sensing direction,

wherein an insulating layer is provided on the ASIC element in an abutment region for the abutment element,

wherein the first portion of the bonding layer has an abutment surface facing the ASIC element,

wherein the insulating layer has a surface facing the MEMS element, and

wherein, when the sensing element deflects to a maximum deflection, the abutment surface of the first portion of the bonding layer contacts the surface of the insulating layer facing the MEMS element.

10. The method for manufacturing a micromechanical sensor device as recited in claim 9, wherein the sensing element has a portion provided orthogonally to the sensing direction, and wherein the abutment element is formed on the portion of the sensing element that is orthogonal to the sensing direction.

12. The method for manufacturing a micromechanical sensor device as recited in claim 9, further comprising:

providing a bonding structure that electrically connects the ASIC element and the MEMS element, wherein the bonding structure is a eutectic mixture of a second portion of the bonding layer and a metal layer of the ASIC element.