METHODS OF FABRICATING MICRO ELECTRO MECHANICAL SYSTEM STRUCTURES

• US 20160009550A1
• Filed: 09/21/2015
• Published: 01/14/2016
• Est. Priority Date: 01/19/2012
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chien, Ting-Ying, Ni, Chyi-Tsong, Su, Ching-Hou, Chiu, Yi Hsun
• Granted Patent: US 9,776,857 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B81C 1/00269 Bonding of solid lids or wafers to the substrate
• CPC Class Codes: B81C 2203/0109 Bonding an individual cap on the substrate
• CPC Class Codes: B81C 2203/019 characterised by the material or arrangement of seals between parts
• CPC Class Codes: H01L 2224/83805 involving forming a eutectic alloy at the bonding interface
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/16235 Connecting to a semiconductor or solid-state bodies, i.e. cap-to-chip

Abstract

A method of fabricating a micro electro mechanical system (MEMS) structure includes providing a first substrate structure including a bonding pad structure. The bonding pad structure has at least one recess therein. A second substrate structure is provided and bonded with the bonding pad structure of the first substrate structure.

Claims

1. A method of fabricating a micro electro mechanical system (MEMS) structure comprising:

providing a first substrate structure including a first bonding pad structure;

providing a recess in the first bonding pad structure, wherein the recess provides for defining a first region and a second region of the first bonding pad structure having a first surface, and a third region of the first bonding pad structure having a second surface, wherein the first surface is parallel to and spaced a distance from the second surface;

providing a second substrate structure including a second bonding pad structure; and

bonding the first surface of the first bonding pad structure in the first and second regions to the second bonding pad structure.

2. The method of claim 1, further comprising:

wherein the providing the recess includes forming a slot in the first bonding pad structure, wherein the slot defines the first region of a first bond pad ring and the second region of a second bond pad ring, wherein the first and second bond pad rings are separated from each other by a width of the slot; and

wherein the bonding includes bonding the first bond pad ring and the second bond pad ring to the second substrate structure.

3. The method of claim 2, wherein the providing the recess further includes forming a second slot continuously extending in the first bonding pad structure, such that the first bonding pad structure includes a third bond pad ring that is separated from the second bond pad ring by the second slot;

and

wherein the bonding includes bonding the third bond pad ring to the second substrate structure.

4. The method of claim 3, wherein the slot and the second slot have a different width.

5. The method of claim 1, wherein the providing the recess includes forming a bonding material that continuously extends along sidewalls of the recess, the sidewalls extending from the first surface to the second surface.

6. The method of claim 1, wherein the bonding does not form an interface between the second surface of the first bonding pad structure and the second bonding pad structure.

7. The method of claim 1, wherein the forming the recess includes forming the first surface comprising a first metal and the second surface comprising the first metal.

8. The method of claim 1, wherein the bonding includes eutectically bonding the second bonding pad structure with the first surface.

9. The method of claim 1, wherein the providing the second substrate structure includes providing the second bonding pad structure having a planar top surface;

and

wherein the bonding includes eutectically bonding a portion of the planar top surface to the first surface.

10. A method of fabricating a micro electro mechanical system (MEMS) structure comprising:

providing a first substrate structure including a first bonding pad structure defined as a first bond pad ring and a second bond pad ring having a slot interposing therebetween;

providing a second substrate structure including a second bonding pad structure, wherein the second bonding pad structure is disposed in a trench recessed from a top surface of the second substrate; and

bonding the first bond pad ring and the second bond pad ring to the second bonding pad structure providing a first and second bonding interface, wherein the first and second bonding interface are disposed within the trench, and wherein at least a portion of the slot extends above the trench.

11. The method of claim 10, wherein the bonding provides for a surface region of the second bonding pad that does not form a physical interface the first substrate, the region being collinear with the slot.

12. The method of claim 11, wherein the surface region of the second bonding pad is coplanar with the first and second bonding interface.

13. The method of claim 10, wherein a width of the first bond pad ring is about 30 microns or less.

15. The method of claim 10, wherein a bonding material continuously extends from the first bond pad ring to the second bond pad ring.

16. The method of claim 10, wherein the bonding is a eutectic bonding process.

17. The method of claim 10, wherein the bonding is a semiconductor to metal eutectic bonding process.

14. The method of claim 0, wherein a width of the slot is about 10 microns or less.

18. A method of fabricating a micro electro mechanical system (MEMS) structure comprising:

providing a first substrate and a second substrate, wherein at least one of the first and second substrates has a MEMS device, and the second substrate has a first bonding pad structure;

providing a third substrate having a second bonding pad structure, wherein the second bonding pad structure includes a recess defining a first bonding region surface and a second bonding region surface, the recess interposing the first and second bonding region surfaces;

performing a first bonding process to bond the first and second substrates to form a MEMS structure; and

after the first bonding process, performing a second bonding process to bond the third substrate to the MEMs structure, wherein the first and second bonding region surfaces are bonded to the first bonding pad structure.

19. The method of claim 18, wherein the first and second substrates are bonded by a fusion bonding process.

20. The method of claim 18, wherein the second bonding process is a eutectic bonding process.