Sequential wafer bonding

• US 9,604,844 B2
• Filed: 07/20/2015
• Issued: 03/28/2017
• Est. Priority Date: 08/27/2013
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Inventors: Bowles, Philip H., Hooper, Stephen R.
• Primary Examiner(s): HUBER, ROBERT T
• Application Number:
  US14/804,110
• Publication Number:
  US 20150321907A1
• Time in Patent Office: 617 Days
• Field of Search: 257/415, 257/E23.002, 257/E25.03, 438/456, 438/458, 438/455, 438/50, 438/51
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/0242 Gyroscopes
• CPC Class Codes: B81B 2207/012 the micromechanical device and the control or processing electronics being separate parts in the same package
• CPC Class Codes: B81B 7/0029 Protection against environmental influences not provided for in groups B81B7/0012 - B81B7/0025
• CPC Class Codes: B81B 7/0041 maintaining a controlled atmosphere with techniques not provided for in B81B7/0038
• CPC Class Codes: B81B 7/04 Networks or arrays of similar microstructural devices
• CPC Class Codes: B81C 1/0023 Packaging together an electronic processing unit die and a micromechanical structure die MEMS packages B81B7/0032; MEMS packaging processes B81C1/00261
• CPC Class Codes: B81C 1/00293 maintaining a controlled atmosphere with processes not provided for in B81C1/00285
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• CPC Class Codes: H01L 2224/11 Manufacturing methods
• CPC Class Codes: H01L 23/10 characterised by the material or arrangement of seals between parts, e.g. between cap and base of the container or between leads and walls of the container
• CPC Class Codes: H01L 29/66007 Multistep manufacturing processes
• CPC Class Codes: H01L 29/84 controllable by variation of applied mechanical force, e.g. of pressure
• 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

Abstract

Embodiments of a sensor device include a sensor substrate and a first cap substrate attached to the sensor substrate with a first bond material. The first bond material is arranged to define a first device cavity. A second cap substrate is attached to the sensor substrate with a second bond material. The second bond material is arranged to define a second device cavity. The second bond material has a lower bonding temperature than the first bond material. The second cap substrate is further secured to the sensor substrate by an adhesive material disposed between the sensor substrate and the second cap substrate.

Claims

1. A sensor device comprising:

a sensor substrate;

a first cap substrate attached to the sensor substrate with a first bond material, the first bond material being arranged to define a first device cavity; and

a second cap substrate attached to the sensor substrate with a second bond material, the second bond material being arranged to define a second device cavity, the second bond material having a lower bonding temperature than the first bond material;

wherein the second cap substrate is further secured to the sensor substrate by an adhesive material disposed between the sensor substrate and the second cap substrate;

wherein a first outermost sidewall of the second cap substrate is offset inwardly from a second outermost sidewall of the first cap substrate;

wherein the sensor substrate has an indent along a third outermost sidewall of the sensor substrate and adjacent the second cap substrate in which the adhesive material is disposed;

wherein a sidewall of the indent is coplanar with the first outermost sidewall of the second cap substrate.

2. The sensor device of claim 1, wherein the first bond material comprises an aluminum-germanium (AlGe) alloy.

3. The sensor device of claim 1, wherein the second bond material is selected from the group consisting of a tin-silver-copper (SnAgCu) alloy, a tin-antimony (SnSb) alloy, a lead-tin (PbSn) alloy, and a lead-tin-silver (PbSnAg) alloy.

4. The sensor device of claim 1, wherein the second bond material is arranged as a sealing ring disposed along a perimeter of the sensor substrate.

5. The sensor device of claim 1, further comprising solder balls attached to the first cap substrate or the second cap substrate, the solder balls having a bonding temperature no lower than the bonding temperature of the second bond material.

6. The sensor device of claim 1, further comprising solder balls attached to the first cap substrate or the second cap substrate, the solder balls comprising the second bond material.

7. The sensor device of claim 1, wherein the sensor substrate has a vent hole in communication with the second device cavity, the vent hole providing a vent path through the sensor substrate.

8. The sensor device of claim 7, wherein the second bond material is arranged in a seal ring disposed between the adhesive material and the vent hole, the seal ring surrounding the vent hole.

9. The sensor device of claim 1, wherein the adhesive material comprises an underfill epoxy material.

10. The sensor device of claim 1, wherein the adhesive material is further disposed at the periphery along outer edges of the second cap substrate.

11. The sensor device of claim 1, wherein the periphery of the second cap substrate is offset inwardly from a boundary of the sensor substrate.

12. The sensor device of claim 1, wherein:

the first device cavity has a first pressure; and

the second device cavity has a second pressure higher than the first pressure.

13. The sensor device of claim 12, wherein the sensor substrate comprises a vent hole such that space enclosed in the second device cavity is present on both sides of the sensor substrate.

14. The sensor device of claim 13, wherein the second bond material is arranged in a seal ring disposed between the adhesive material and the vent hole.

19. The sensor device of claim 1, wherein the adhesive material is disposed inwardly of the second bonding material.

15. A sensor device comprising:

a sensor substrate;

a first cap substrate attached to the sensor substrate with a first bond material, the first bond material being arranged to define a first device cavity; and

a second cap substrate attached to the sensor substrate with a second bond material, the second bond material being arranged to define a second device cavity, the second bond material having a lower bonding temperature than the first bond material;

wherein the second cap substrate is further secured to the sensor substrate by an adhesive material disposed between the sensor substrate and the second cap substrate, and

wherein the sensor substrate has a vent hole in communication with the second device cavity, the vent hole providing a vent path through the sensor substrate;

wherein the first device cavity has a first pressure; and

the second device cavity has a second pressure higher than the first pressure.

16. The sensor device of claim 15, wherein the second bond material is arranged in a seal ring disposed between the adhesive material and the vent hole, the seal ring surrounding the vent hole.

17. The sensor device of claim 15, wherein the second bond material is arranged as a sealing ring disposed along a perimeter of the sensor substrate.

18. The sensor device of claim 15, wherein the adhesive material comprises an underfill epoxy material.