MEMS devices and fabrication methods thereof

• US 10,160,633 B2
• Filed: 09/26/2016
• Issued: 12/25/2018
• Est. Priority Date: 06/15/2012
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chu, Chia-Hua, Cheng, Chun-Wen, Lee, Te-Hao, Lin, Chung-Hsien
• Primary Examiner(s): Nicely, Joseph C
• Assistant Examiner(s): Vuong, Thai T
• Application Number:
  US15/276,212
• Publication Number:
  US 20170008758A1
• Time in Patent Office: 820 Days
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2203/0307 Anchors
• CPC Class Codes: B81B 2203/04 Electrodes
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 3/0054 For holding or placing an element in a given position
• CPC Class Codes: B81C 1/00238 Joining a substrate with an electronic processing unit and a substrate with a micromechanical structure

Abstract

A device includes a carrier having a plurality of cavities, a micro-electro-mechanical system (MEMS) substrate bonded on the carrier, wherein the MEMS substrate comprises a first side bonded on the carrier, a moving element over a bottom electrode, wherein the bottom electrode is formed of polysilicon and a second side having a plurality of bonding pads and a semiconductor substrate bonded on the MEMS substrate, wherein the semiconductor substrate comprises a top electrode and the first moving element is between the top electrode and the bottom electrode.

Claims

1. A semiconductor device comprising:

a carrier having a plurality of cavities;

a micro-electro-mechanical system (MEMS) substrate bonded on the carrier, wherein the MEMS substrate comprises;

a first side bonded on the carrier;

a first moving element over a bottom electrode, wherein the bottom electrode is formed of polysilicon; and

a second side having a plurality of bonding pads; and

a semiconductor substrate bonded on the MEMS substrate, wherein the semiconductor substrate comprises a top electrode, and wherein the first moving element is between the top electrode and the bottom electrode.

2. The semiconductor device of claim 1, wherein:

the MEMS substrate comprises a plurality of air channels coupled to the cavities of the carrier.

3. The semiconductor device of claim 1, wherein:

each cavity of the plurality of cavities comprises an extrusion.

4. The semiconductor device of claim 1, further comprising:

a first dielectric layer deposited on the first side of the MEMS substrate;

a vapor HF stop layer formed over the first dielectric layer;

a second dielectric layer formed over the vapor HF stop layer; and

a bonding layer formed over the second dielectric layer.

5. The semiconductor device of claim 4, where:

the first dielectric layer is a first oxide layer;

the vapor HF stop layer is a low stress nitride layer;

the second dielectric layer is a second oxide layer; and

the bonding layer is formed of polysilicon.

6. The semiconductor device of claim 1, further comprising:

a bonding material layer on the semiconductor substrate, wherein the bonding material layer is conductive.

7. The semiconductor device of claim 1, further comprising:

a conductive layer formed between the semiconductor substrate and the MEMS substrate, wherein the conductive layer is thinner than the MEMS substrate.

8. The semiconductor device of claim 1, further comprising:

an anchor region formed adjacent to the first side of the MEMS device, and wherein three sides of the anchor region are wrapped by a polysilicon layer.

9. The semiconductor device of claim 1, further comprising:

a mechanical bump partially embedded in a second moving element.

10. The semiconductor device of claim 9, wherein:

the mechanical bump is formed of polysilicon.

11. An apparatus comprising:

a carrier having a plurality of cavities;

a micro-electro-mechanical system (MEMS) device bonded on the carrier, wherein the MEMS device comprises;

a first side bonded on the carrier;

a moving element over a bottom electrode;

an anchor region formed adjacent to the first side of the MEMS device, and wherein three sides of the anchor region are wrapped by a polysilicon layer; and

a second side having a plurality of bonding pads; and

a semiconductor substrate bonded on the MEMS device, wherein the semiconductor substrate comprises a top electrode, and wherein the moving element is between the top electrode and the bottom electrode.

12. The apparatus of claim 11, wherein:

the bottom electrode is formed of polysilicon.

13. The apparatus of claim 11, wherein:

a first side of the anchor region is in contact with a substrate of the MEMS device; and

a second side and sidewalls of the anchor region is in contact with the polysilicon layer.

14. The apparatus of claim 11, further comprising:

a bonding interface layer in contact with the carrier, wherein;

the bonding interface layer covers at least one of the plurality of cavities; and

the bonding interface layer and the bottom electrode are separated by at least one dielectric layer.

15. The apparatus of claim 14, wherein:

the bonding interface layer is formed of polysilicon.

16. A device comprising:

a carrier having a plurality of cavities, wherein a first opening of a first cavity is covered by a bonding interface layer and a second opening of the first cavity is exposed through a gap between two adjacent bonding interface layers;

a micro-electro-mechanical system (MEMS) device bonded on the carrier, wherein the MEMS device comprises;

the bonding interface layer on a first side of the MEMS device;

a dielectric layer on the bonding interface layer;

a bottom electrode over the dielectric layer;

a first moving element over the bottom electrode; and

a semiconductor substrate bonded on a second side of the MEMS substrate, wherein the semiconductor substrate comprises a top electrode, and wherein the first moving element is between the bottom electrode and the top electrode.

17. The device of claim 16, wherein:

the bottom electrode is formed of polysilicon.

18. The device of claim 16, further comprising:

an anchor region formed over the bottom electrode, and wherein three sides of the anchor region are wrapped by a polysilicon layer.

19. The device of claim 16, further comprising:

a second moving element between the bottom electrode and the top electrode, wherein a mechanical bump is partially embedded in the second moving element, and wherein the mechanical bump is formed of polysilicon.

20. The device of claim 16, further comprising:

a polysilicon layer formed between the top electrode and the first moving element.