MICRO-ELECTRO MECHANICAL SYSTEM (MEMS) STRUCTURES WITH THROUGH SUBSTRATE VIAS AND METHODS OF FORMING THE SAME

• US 20130193527A1
• Filed: 03/23/2012
• Published: 08/01/2013
• Est. Priority Date: 01/31/2012
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: CHU, Chia-Hua, CHANG, Kuei-Sung, LEE, Te-Hao
• Granted Patent: US 9,466,532 B2
• Time in Patent Office: Days
• US Class Current: 257/414
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 2207/095 through the lid
• CPC Class Codes: B81B 7/007 Interconnections between the MEMS and external electrical signals
• 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 2203/036 Fusion bonding
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01L 21/76898 formed through a semiconductor substrate

Abstract

The present disclosure includes micro-electro mechanical system (MEMS) structures and methods of forming the same. Substrates of the MEMS structures are bonded together by fusion bonding at high processing temperatures, which enables more complete removal of chemical species from the dielectric materials in the substrates prior to sealing cavities of the MEMS structures. Fusion bonding of MEMS structures reduces outgassing of chemical species and is compatible with the cavity formation process. The MEMS structures bonded by fusion bonding are mechanically stronger compared to eutectic bonding due to a higher bonding ratio. In addition, fusion bonding enables the formation of through substrate vias (TSVs) in the MEMS structures.

Claims

12-1. The device of claim 1, wherein the at least one cavity is formed by etching the capping substrate.

14. A micro-electro mechanical system (MEMS) structure, comprising:

a first substrate embedded with a through substrate via (TSV), wherein the first substrate has a first cavity;

a second substrate structure bonded to the first substrate by a fusion bonding layer, wherein the second substrate structure includes at least one MEMS device; and

a third substrate structure coupled to the second substrate structure, wherein the third substrate structure has an integrated circuit (IC) device, and wherein the third substrate structure has a second cavity;

wherein the first and second cavities surround at least a portion of the at least one MEMS device.

15. The MEMS structure of claim 14, wherein the fusion bonding layer includes Si, SiO₂, or a combination of thereof.

16. The MEMS structure of claim 14, wherein at least one of the first and the second cavities is formed by etching a dielectric layer.

17. The MEMS structure of claim 14, wherein a bonding structure having an under-bump-metallurgy (UBM) layer is formed over the first substrate, and wherein the UBM layer is in contact with a metal layer used to fill the TSV.

18. A method of forming a micro-electro mechanical system (MEMS) structure, the method comprising:

providing a first substrate structure; and

bonding a second substrate structure to the first substrate structure using fusion bonding, wherein the second substrate structure includes at least one micro-electro mechanical system (MEMS) device, and wherein there is at least one cavity surrounding at least a portion of the MEMS device.

19. The method of claim 18, further comprising:

forming a TSV in the first substrate structure and in a fusion bonding layer.

20. The method of claim 18, further comprising:

forming an under bump metallurgy (UBM) layer over the first substrate structure, wherein the UBM layer contacts a metal layer used to fill the TSV.