Sealed cavity

• US 8,395,249 B2
• Filed: 08/01/2011
• Issued: 03/12/2013
• Est. Priority Date: 02/22/2008
• Status: Active Grant

• Current Assignee: Qorvo US, Inc. (Qorvo, Inc.)
• Original Assignee: Cavendish Kinetics Ltd. (Qorvo, Inc.)
• Inventors: Renault, Mickael
• Primary Examiner(s): Lee, Hsien Ming
• Application Number:
  US13/195,215
• Publication Number:
  US 20110285035A1
• Time in Patent Office: 589 Days
• Field of Search: 438 51- 55, 438/107, 438125-127, 257/E21.499, 257/E21.502, 257/678, 257/787, 257/789, 257/795
• US Class Current: 257/678
• 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

Abstract

Embodiments disclosed herein generally include methods of sealing a cavity in a device structure. The cavity may be opened by etching away sacrificial material that may define the cavity volume. Material from below the cavity may be sputter etched and redeposited over and in passageways leading to the cavity to thereby seal the cavity. Material may be sputter etched from above the cavity and redeposited in the passageways leading to the cavity as well. The sputter etching may occur in a substantially inert atmosphere. As the sputter etching is a physical process, little or no sputter etched material will redeposit within the cavity itself. The inert gases may sweep out any residual gases that may be present in the cavity after the cavity has been opened. Thus, after the sputter etching, the cavity may be substantially filled with inert gases that do not negatively impact the cavity.

Claims

1. A device structure, comprising:

a substrate;

one or more layers coupled to and disposed over the substrate such that a cavity is embedded between the substrate and the one or more layers, the device structure having a first passage that extends from the cavity; and

material sealing the first passage, wherein the material comprises material that has been removed from one or more of the substrate and the one or more layers and redeposited in the first passage.

2. The device structure of claim 1, wherein the device structure has a second passage that extends from the cavity.

3. The device structure of claim 2, wherein the material sealing the first passage also seals the second passage.

4. The device structure of claim 1, wherein the device structure is a micro-electromechanical device.

5. The device structure of claim 1, wherein the material sealing the first passage comprises material removed from the substrate.

6. The device structure of claim 1, wherein the material sealing the first passage comprises material removed from the one or more layers.

7. The device structure of claim 1, further comprising a device disposed within the cavity.

8. The device structure of claim 7, wherein the first passage has no line of sight path between the device and an end of the first passage opposite the cavity.

9. The device structure of claim 1, further comprising a blocker disposed within the first passage.

10. A device structure, comprising:

a substrate;

one or more layers coupled to and disposed over the substrate such that a cavity is embedded between the substrate and the one or more layers, the device structure having a first passage that extends from the cavity, wherein the first passage has no line of sight path between the cavity and an end of the first passage opposite the cavity;

a blocker disposed within the first passage; and

material sealing the first passage, wherein the material comprises material that has been removed from one or more of the substrate and the one or more layers and redeposited in the first passage.

11. The device structure of claim 10, wherein the device has a second passage that extends from the cavity.

12. The device structure of claim 11, wherein the material sealing the first passage also seals the second passage.

13. The device structure of claim 10, wherein the device structure is a micro-electromechanical device.

14. The device structure of claim 10, wherein the material sealing the first passage comprises material removed from the substrate.