Micromechanical component

• US 9,840,410 B2
• Filed: 09/16/2016
• Issued: 12/12/2017
• Est. Priority Date: 09/18/2015
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Classen, Johannes
• Primary Examiner(s): Nguyen, Cuong Q
• Assistant Examiner(s): Kim, Tong-Ho
• Application Number:
  US15/268,017
• Publication Number:
  US 20170081180A1
• Time in Patent Office: 452 Days
• Field of Search: 257418, 257415
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2207/012 the micromechanical device and the control or processing electronics being separate parts in the same package
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 7/007 Interconnections between the MEMS and external electrical signals
• CPC Class Codes: B81C 1/00238 Joining a substrate with an electronic processing unit and a substrate with a micromechanical structure
• CPC Class Codes: B81C 2203/0109 Bonding an individual cap on the substrate
• CPC Class Codes: B81C 2203/035 Soldering
• CPC Class Codes: B81C 2203/0792 Forming interconnections between the electronic processing unit and the micromechanical structure
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: H01L 2224/11 Manufacturing methods

Abstract

A method for manufacturing a micromechanical component, including: providing a MEMS wafer; structuring the MEMS wafer proceeding from a surface of a second substrate layer of the MEMS wafer, at least one electrically conducting connection being formed between a first substrate layer and the second substrate layer of the MEMS wafer; providing a cap wafer; joining the MEMS wafer to the cap wafer; structuring the MEMS wafer proceeding from a surface of the first substrate layer of the MEMS wafer; providing an ASIC wafer; and joining the ASIC wafer to the joint of the MEMS wafer and the cap wafer.

Claims

1. A method for manufacturing a micromechanical component, the method comprising:

providing a micro-electro-mechanical system (MEMS) wafer;

structuring the MEMS wafer proceeding from a surface of a second substrate layer of the MEMS wafer to form a second movable MEMS structure, the surface of the second substrate layer facing in a second direction, at least one electrically conducting connection being formed between a first substrate layer and the second substrate layer of the MEMS wafer;

providing a cap wafer;

joining the MEMS wafer to the cap wafer;

structuring the MEMS wafer proceeding from a surface of the first substrate layer of the MEMS wafer to form a first movable MEMS structure, the first movable MEMS structure and the second movable MEMS structure situated on top of one another at least in sections, the surface of the first substrate layer facing in a first direction substantially opposite to the second direction;

providing an application-specific integrated circuit (ASIC) wafer; and

joining the ASIC wafer to the joint of the MEMS wafer and the cap wafer.

2. The method of claim 1, wherein the joining of the ASIC wafer to the joint of the MEMS wafer and the cap wafer is carried out with a metallic bonding process.

3. The method of claim 2, wherein the metallic bonding process is configured as a eutectic Al—

Ge bonding process or as a Cu—

Sn-SLID bonding process or as a metallic direct bonding process.

4. The method of claim 1, wherein the electrically conducting connection between the first and second substrate layers of the MEMS wafer is formed of polysilicon or of a metal, in particular tungsten.

5. The method of claim 1, wherein at least one contacting element for electrically contacting the micromechanical component is configured as a through-silicon via in the ASIC wafer.

6. The method of claim 1, wherein at least one contacting element for electrically contacting the micromechanical component is configured as a wire bonding element.

7. The method of claim 1, wherein the MEMS wafer is formed with an SOI wafer.

8. The method of claim 1, wherein the joining of the MEMS wafer to the cap wafer is performed after the structuring the MEMS wafer to form the second movable MEMS structure.

9. The method of claim 1, wherein the structuring of the MEMS wafer to form the first movable MEMS structure is performed after the joining the MEMS wafer to the cap wafer.

10. The method of claim 1, wherein the joining of the ASIC wafer to the joint of the MEMS wafer and the cap wafer is performed after the structuring the MEMS wafer to form the first movable MEMS structure.

11. The method of claim 1, wherein the structuring of the MEMS wafer to form the first movable MEMS structure is performed after the structuring of the MEMS wafer to form the second movable MEMS structure.

12. A micromechanical component, comprising:

a micro-electro-mechanical system (MEMS) wafer including at least two movable MEMS structures situated on top of one another at least in sections, a first of the MEMS structures being formed from a first substrate layer of the MEMS wafer and a second of the MEMS structures being formed from a second substrate layer of the MEMS wafer, the first substrate layer and the second substrate layer of the MEMS wafer being separated from each other by an insulating layer at least in sections and electrically conductively connected to one another at least in sections;

an application-specific integrated circuit (ASIC) wafer, the MEMS wafer being functionally joined to the ASIC wafer; and

a cap wafer to cap the ASIC wafer and the MEMS wafer.

13. The micromechanical component of claim 12, wherein at least one movable structure of the MEMS wafer includes a monocrystalline silicon.

14. The micromechanical component of claim 12, wherein the two MEMS structures are electrically conductively connected to one another or electrically insulated from one another.

15. The micromechanical component of claim 12, wherein a contacting element for electrically contacting the component is formed on the ASIC wafer and/or includes a through-silicon via of the ASIC wafer.

16. The micromechanical component of claim 12, wherein the micromechanical component is an inertial sensor.

17. The micromechanical component of claim 12, wherein the insulating layer includes an oxide layer.