Micromechanical component and method for fabricating a micromechanical component

• US 7,964,428 B2
• Filed: 04/03/2006
• Issued: 06/21/2011
• Est. Priority Date: 04/05/2005
• Status: Expired due to Fees

• Current Assignee: Litef GmbH (Northrop Grumman Corporation)
• Original Assignee: Litef GmbH (Northrop Grumman Corporation)
• Inventors: Breng, Uwe, Geiger, Wolfram
• Primary Examiner(s): Graybill; David E
• Application Number:
  US11/887,470
• Publication Number:
  US 20090152705A1
• Time in Patent Office: 1,905 Days
• Field of Search: None
• US Class Current: 438/51
• CPC Class Codes: B81C 1/00333 Aspects relating to packaging of MEMS devices, not covered by groups B81C1/00269 - B81C1/00325
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/1461 MEMS

Abstract

A method for fabricating a microelectromechanical or microoptoelectromechanical component. The method includes producing first and second layer composites. The first has a first substrate and a first insulation layer, which covers at least one part of the surface of the first substrate, while the second has a second substrate and a second insulation layer, which covers at least one part of the surface of the second substrate. An at least partly conductive structure layer is applied to the first insulation layers and the second composite is applied to the structure layer so that the second insulation layer adjoins the structure layer. The first and second layer composites and the structure layer are configured so that at least one part of the structure layer that comprises the active area of the microelectromechanical or microoptoelectromechanical component is hermetically tightly sealed by the first and second layer composites. Contact holes are formed for making contact with conductive regions of the structure layer within the first and/or second substrate.

Claims

1. A method for fabricating a micromechanical component, comprising the following steps:

producing a first layer composite having a first substrate and a first insulation layer, which covers at least one part of a first surface of the first substrate, wherein first depressions are produced in the first surface of the first substrate,

producing a second layer composite having a second substrate and a second insulation layer, which covers at least one part of a surface of the second substrate,

after forming the first depressions, applying an at least partly conductive structure layer to the first layer composite, wherein the structure layer is formed on the insulation layer and over portions of the first substrate, in which the first depressions are produced,

applying the second composite to the structure layer in such a way that the second insulation layer adjoins the structure layer,

wherein the first and second layer composites and also the structure layer are configured in such a way that at least one part of the structure layer which comprises an active area comprising an active structure of the component is sealed by the first and second layer composites,

after applying the second composite to the structure layer, forming contact holes within the first substrate for making contact with conductive regions of the structure layer,

wherein lateral positions of the contact holes at least partly overlap with lateral positions of the first depressions, and

wherein the lateral positions of the first depressions at least partly overlap with lateral positions of the conductive regions of the structure layer to be contacted through the contact holes.

2. The method as claimed in claim 1, characterized in that the active structure is produced by patterning the structure layer, wherein the patterning is effected before or after the structure layer is applied to the first layer composite.

3. The method as claimed in claim 1, characterized in that regions of the first surface of the first substrate which directly adjoin the first depressions are not covered by the first insulation layer.

4. The method as claimed in claim 1, characterized in that second depressions are produced in that side of the first and/or second substrate which faces the structure layer before the structure layer is applied to the first layer composite, lateral positions of said second depressions at least partly overlap with lateral positions of the active structure of the structure layer.

5. The method as claimed in claim 1, characterized in that third depressions are produced in a second surface of the first substrate which is opposite to the first surface of the first substrate, said third depressions serving as breaking points.

6. The method as claimed claim 1, characterized in that trenches are produced in the structure layer during the patterning of the structure layer, said trenches electrically insulating the active structure from outer regions of the structure layer.

7. The method as claimed in claim 1, characterized in that, for forming the contact holes, proceeding from a second surface of the first substrate which is opposite to the first surface of the first substrate, at least one part of the first substrate is removed as far as a vertical position of bottoms of the first depressions.

8. The method as claimed in claim 1, characterized in that after the contact holes have been formed, a metal layer is deposited on a second surface of the first substrate which is opposite to the first surface of the first substrate.

9. The method as claimed in claim 1, 4 or 5, characterized in that the contact holes, the depressions and/or the structure layer are formed by means of an etching method.

10. The method as claimed in claim 1, characterized in that the first substrate, the second substrate and also the structure layer are composed of the same semiconductor material.

11. The method as claimed in claim 1, characterized in that structure layer depressions are formed in the structure layer, positions of said structure layer depressions at least partly overlap with the lateral positions of the active structure of the structure layer.

12. The method as claimed in claim 1, characterized in that insulation layer depressions are formed in the first and/or second insulation layer, lateral positions of said insulation layer depressions at least partly overlap with lateral positions of the active structure of the structure layer.

13. The method as claimed in claim 12, characterized in that the insulation layer depressions are configured to stop a movement of a part of the active structure.

18. The method as claimed in claim 9, wherein the semiconductor material is silicon.

14. A method for fabricating a micromechanical component, comprising the following steps:

producing first depressions in a first surface of a first nonconductive substrate,

after producing the first depressions, applying an at least partly conductive structure layer to the first surface of the first nonconductive substrate, wherein the structure layer is formed over portions of the first substrate, in which the first depressions are produced,

applying a second nonconductive substrate to the structure layer,

wherein the first and second substrates and also the structure layer are configured in such a way that at least one part of the structure layer which comprises an active area of the component is sealed by the first and second substrates,

after applying the second nonconductive substrate to the structure layer, forming contact holes within the first substrate for making contact with conductive regions of the structure layer,

wherein lateral positions of the contact holes at least partly overlap with lateral positions of the first depressions, and

wherein the lateral positions of the first depressions at least partially overlap with lateral positions of the conductive regions of the structure layer to be contacted through the contact holes.

15. The method as claimed in claim 14, characterized in that the first and second substrates comprise quartz or glass.

16. The method as claimed in claim 14, characterized in that the first depressions have a stepped form in such a way that lateral dimensions of upper regions of the first depressions are larger than the lateral dimensions of lower regions of the first depressions, wherein the upper regions are arranged near the first surface of the first substrate and wherein the lower regions are arranged further from the first surface of the first substrate than the upper regions.

17. The method as claimed in claim 16, characterized in that the stepped form of the first depressions is produced by means of a two-stage patterning process.