Integrated heater for gettering or outgassing activation

• US 9,718,679 B2
• Filed: 01/15/2015
• Issued: 08/01/2017
• Est. Priority Date: 06/27/2011
• Status: Active Grant

• Current Assignee: Invensense Incorporated (TDK Corporation)
• Original Assignee: Invensense Incorporated (TDK Corporation)
• Inventors: Lim, Martin
• Primary Examiner(s): Vu, David
• Assistant Examiner(s): INOUSSA, MOULOUCOULAY
• Application Number:
  US14/598,138
• Publication Number:
  US 20150158720A1
• Time in Patent Office: 929 Days
• Field of Search: 257 15, 257414, 257416, 257417, 257E23193, 257723, 257E2318, 257E21501, 438 48- 52, 438455-459, 438476
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/0242 Gyroscopes
• CPC Class Codes: B81B 7/02 containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] B81B7/04 takes precedence
• CPC Class Codes: B81C 1/00285 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters

Abstract

A Microelectromechanical Systems (MEMS) structure with integrated heater is disclosed. The MEMS structure with integrated heater comprises a first substrate with cavities, bonded to a second substrate, forming a plurality of sealed enclosures of at least two types. Each of the plurality of sealed enclosures is defined by the first substrate, the second substrate, and a seal-ring material, where the first enclosure type further includes at least one of a gettering element to decrease cavity pressure in the first enclosure type or an outgassing element to increase cavity pressure in the first enclosure type when activated. The first enclosure type further comprises at least one heater integrated into the first substrate adjacent to the gettering element or the outgassing element to adjust the temperature of the gettering element or the outgassing element thereby providing heating to the gettering element or the outgassing element.

Claims

1. A microelectromechanical systems (MEMS) structure comprising:

a first substrate with cavities, bonded to a second substrate, that forms a plurality of hermetically sealed enclosures of at least two types comprising at least a first hermetically sealed enclosure and a second hermetically sealed enclosure, wherein each of the plurality of hermetically sealed enclosures is defined by the first substrate, the second substrate, and a seal-ring material,

wherein a first enclosure type of the first hermetically sealed enclosure or the second hermetically sealed enclosure further includes a gettering element configured to decrease cavity pressure in the first enclosure type or an outgassing element configured to increase cavity pressure in the first enclosure type, and

wherein the first enclosure type further includes at least one heater integrated into the second substrate adjacent to the gettering element or the outgassing element configured to adjust the temperature of the gettering element or the outgassing element and configured to adjust a gas composition by temperature specific selective absorption or desorption of the gettering element or the outgassing element, respectively, in the first enclosure type of the first hermetically sealed enclosure or the second hermetically sealed enclosure.

2. The MEMS structure of claim 1, wherein the first substrate is a MEMS substrate.

3. The MEMS structure of claim 2, wherein the second substrate comprises a CMOS substrate.

4. The MEMS structure of claim 1;

wherein the first substrate is a CMOS substrate.

5. The MEMS structure of claim 1, wherein the second substrate comprises a MEMS substrate.

6. The MEMS structure of claim 1, wherein the first hermetically sealed enclosure and the second hermetically sealed enclosure are at different pressures.

7. The MEMS structure of claim 1, wherein the first hermetically sealed enclosure and the second hermetically sealed enclosure contain different gas compositions.

8. The MEMS structure of claim 1, wherein the seal-ring material is comprised of at least one of a reflowed solder, a glass frit, an anodic bond, or an epoxy bond.

9. A Microelectromechanical Systems (MEMS) structure comprising:

a MEMS substrate with cavities bonded to a second substrate, that form a plurality of hermetically sealed enclosures of at least two types,

wherein each of the plurality of hermetically sealed enclosures is defined by the MEMS substrate, the second substrate, and a seal-ring material, and

wherein a first enclosure type of the plurality of hermetically sealed enclosures of at least two types further includes an integrated heater of a complementary metal-oxide semiconductor (CMOS) substrate configured to adjust pressure in the first enclosure type by adjusting gas composition by temperature specific selective absorption or desorption of a gettering element configured to decrease cavity pressure in the first enclosure type or an outgassing element configured to increase cavity pressure in the first enclosure type, respectively.

10. The MEMS structure of claim 9, wherein the second substrate comprises a CMOS substrate.