Monolithic integration of MEMS and IC devices

• US 10,189,705 B1
• Filed: 10/25/2017
• Issued: 01/29/2019
• Est. Priority Date: 10/25/2017
• Status: Active Grant

• Current Assignee: Vanguard International Semiconductor Singapore Pte. Ltd. (Vanguard International Semiconductor Corporation)
• Original Assignee: Globalfoundries Singapore Pte Limited (GlobalFoundries, Inc.)
• Inventors: Campanella Pineda, Humberto, Stamper, Anthony Kendall, Qian, You, Poikayil Satheesh, Sharath, Maling, Jeffrey C., Kumar, Rakesh
• Primary Examiner(s): Kusumakar, Karen
• Application Number:
  US15/793,965
• Time in Patent Office: 461 Days
• CPC Class Codes: B81B 2203/04 Electrodes
• CPC Class Codes: B81B 2207/015 the micromechanical device and the control or processing electronics being integrated on the same substrate
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 2207/094 Feed-through, via
• 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 1/00246 Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate
• CPC Class Codes: B81C 2203/0735 Post-CMOS, i.e. forming the micromechanical structure after the CMOS circuit
• CPC Class Codes: B81C 2203/0778 Topology for facilitating the monolithic integration not provided for in B81C2203/0764 - B81C2203/0771
• CPC Class Codes: B81C 2203/0792 Forming interconnections between the electronic processing unit and the micromechanical structure
• CPC Class Codes: H01L 2224/11 Manufacturing methods

Abstract

An integrated monolithic device with a micro-electromechanical system (MEMS) and an integrated circuit (IC) and a method of forming thereof is disclosed. The monolithic device includes a substrate with IC components and a MEMS formed over the IC. A back-end-of-line (BEOL) dielectric having IC interconnect pads in a pad level is formed over the substrate. A MEMS is formed over the BEOL dielectric with the IC interconnect pads. The MEMS includes a MEMS stack having an active MEMS layer and patterned top and bottom MEMS electrodes formed on the top and bottom surfaces of the active MEMS layer. IC MEMS contact vias are formed at least partially through the active MEMS layer. IC MEMS contacts are formed in the IC MEMS contact vias in the active MEMS layer and configured to couple to the IC interconnect pads.

Claims

1. A device comprising:

a substrate having first and second surfaces;

integrated circuit (IC) components disposed on the first surface of the substrate;

a back-end-of-line (BEOL) dielectric with at least one interlevel dielectric (ILD) level with interconnects and contacts coupled to the IC components disposed on the first surface of the substrate;

a pad level on an uppermost ILD level, the pad level comprises IC interconnect pads coupled to the IC components via the at least one ILD level;

a micro electromechanical system (MEMS) stack disposed over the pad level, the MEMS stack includes

a MEMS region having a MEMS component with MEMS electrodes and MEMS contacts coupled to the MEMS electrodes, and

an IC region over the IC interconnect pads, the IC region includes IC MEMS contacts configured to be coupled to the IC interconnect pads; and

a MEMS encapsulation layer disposed over the MEMS stack, including the MEMS and IC regions, the MEMS encapsulation layer comprises a planar top surface, wherein the encapsulation layer comprises MEMS solder bumps in the MEMS region and IC MEMS solder bumps in the IC region.

2. The device of claim 1 comprises a MEMS interposer disposed between the BEOL dielectric and the MEMS stack, wherein the MEMS interposer comprises:

a dielectric interposer with top and bottom MEMS interposer surfaces; and

IC interposer contacts which couple the IC MEMS contacts to the IC interconnect pads.

3. The device of claim 2 wherein an IC interposer contact of the IC interposer contacts comprises an array interposer contact having an array of via contacts coupled to an IC interconnect pad of the IC interconnect pads.

4. The device of claim 2 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack, wherein the IC MEMS contact vias extend partially through the MEMS stack;

the MEMS contacts line MEMS contact vias in the MEMS stack;

upper portions of the IC interposer contacts extend through a lower portion of the MEMS stack, the IC interposer contacts are coupled to the IC MEMS contacts; and

wherein the IC MEMS solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

5. The device of claim 2 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack, wherein the MEMS contact vias extend partially through the MEMS stack;

the MEMS contacts line MEMS contact vias in the MEMS stack;

tops of IC interposer contacts are coupled to the IC MEMS contacts; and

wherein the IC MEMS solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

6. The device of claim 2 wherein the IC MEMS contacts, the IC MEMS solder bumps, and the IC interposer contacts comprise solder and form unitary contacts.

8. The device of claim 1 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack; and

the MEMS contacts line MEMS contact vias in the MEMS stack.

9. The device of claim 8 comprises:

the MEMS solder bumps extending through the encapsulation layer, the MEMS solder bumps are coupled to the MEMS contacts; and

the IC MEMS solder bumps extending through the encapsulation layer, the IC MEMS solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

7. A device comprising:

a substrate having first and second surfaces;

integrated circuit (IC) components disposed on the first surface of the substrate;

a back-end-of-line (BEOL) dielectric disposed on the first surface of the substrate, the BEOL dielectric covering the IC components, wherein the BEOL dielectric comprises

a plurality of interlevel dielectric (ILD) levels with contacts and interconnect lines for interconnecting the IC components, and

a pad level on an uppermost ILD level, the pad level comprises IC interconnect pads; and

a micro electromechanical system (MEMS) disposed over a top of the BEOL dielectric with the IC interconnect pads, wherein the MEMS comprises

a MEMS stack, the MEMS stack is disposed directly on the top of the BEOL dielectric, the MEMS stack having a top MEMS surface and a bottom MEMS surface, wherein the MEMS stack includes

an active MEMS layer having a top active MEMS layer surface and a bottom active MEMS layer surface,

a patterned top MEMS electrode disposed on the top active MEMS layer surface, and

a patterned bottom MEMS electrode disposed on the bottom active MEMS layer surface, and

IC MEMS contacts, wherein the IC MEMS contacts line IC MEMS contact vias which are disposed at least partially through the active MEMS layer, wherein

the IC MEMS contact vias extend completely through the MEMS stack to expose top surfaces of the interposer contacts, and

the IC MEMS contacts directly contact the IC interconnect pads.

10. A method of forming a device, comprising:

providing a substrate with first and second surfaces, the substrate is prepared with integrated circuit (IC) components on the first surface of the substrate and a back-end-of-line (BEOL) dielectric formed over the first surface of the substrate with at least one interlevel dielectric (ILD) level with interconnects and contacts coupled to the IC components;

forming a pad level on an uppermost ILD level, the pad level comprises IC interconnect pads coupled to the IC components via the at least one ILD level;

forming a micro electromechanical system (MEMS) stack over the pad level, the MEMS stack includes

a MEMS region having a MEMS component with MEMS electrodes and MEMS contacts coupled to the MEMS electrodes, and

an IC region over the IC interconnect pads, the IC region includes IC MEMS contacts configured to be coupled to the IC interconnect pads;

forming a planar encapsulation layer over the MEMS stack, including the IC and MEMS regions; and

forming MEMS solder bumps and IC solder bumps in the encapsulation layer, wherein the MEMS solder bumps are coupled to the MEMS contacts and the IC solder bumps are coupled to the IC MEMS contacts.

11. The method of claim 10 comprises:

forming a MEMS interposer disposed between the BEOL dielectric and the MEMS stack, wherein the MEMS interposer comprises a dielectric interposer with top and bottom MEMS interposer surfaces; and

forming IC interposer contacts in the MEMS interposer, the IC interposer contacts are coupled the IC interconnect pads.

12. The method of claim 11 wherein forming an IC interposer contact of the IC interposer contacts comprises forming an array interposer contact having an array of via contacts.

13. The method of claim 11 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack, wherein the MEMS contact vias extend partially through the MEMS stack;

the MEMS contacts line MEMS contact vias in the MEMS stack;

upper portions of the IC interposer contacts extend through a lower portion of the IC interposer contacts are coupled to the IC MEMS contacts; and

MEMS stack, the

wherein the IC solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

14. The method of claim 11 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack, wherein the IC MEMS contact vias extend partially through the MEMS stack;

the MEMS contacts line MEMS contact vias in the MEMS stack;

tops of IC interposer contacts are coupled to the IC MEMS contacts; and

wherein the IC solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

15. The method of claim 11 wherein the IC MEMS contacts, the IC solder bumps, and IC interposer contacts comprise solder and form unitary contacts.

16. The method of claim 10 wherein:

the IC MEMS contacts line IC MEMS contact vias in the MEMS stack; and

the MEMS contacts line MEMS contact vias in the MEMS stack.

17. The method of claim 16 wherein:

the MEMS solder bumps extending through the encapsulation layer, the MEMS solder bumps are coupled to the MEMS contacts; and

the IC MEMS solder bumps extending through the encapsulation layer, the IC MEMS solder bumps fill the IC MEMS contact vias lined with the IC MEMS contacts.

18. The method of claim 10 further comprising:

forming a MEMS interposer disposed between the BEOL dielectric and the MEMS stack, wherein the MEMS interposer comprises a dielectric interposer with top and bottom MEMS interposer surfaces; and

forming IC interposer contacts in the MEMS interposer, the IC interposer contacts are coupled the IC interconnect pads.