SENSOR HAVING PARTICLE BARRIER

• US 20150355223A1
• Filed: 01/31/2013
• Published: 12/10/2015
• Est. Priority Date: 01/31/2013
• Status: Active Application

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Wu, Jennifer, Alley, Rodney L., Walmsley, Robert G., Milligan, Donald J.
• Granted Patent: US 10,267,822 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0221 Variable capacitors
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 7/0029 Protection against environmental influences not provided for in groups B81B7/0012 - B81B7/0025
• CPC Class Codes: G01C 19/5769 Manufacturing; Mounting; Housings
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up

Abstract

A sensor having a particle barrier is described. In an example, a sensor includes: first and second electrode sets respectively disposed upon a planar support surface and a proof mass that is compliantly displaceable along a first axis substantially parallel to the planar support surface; and a first barrier disposed on the planar support around the first electrode set having a height less than a gap between the planar support and the proof mass to mitigate particle migration into the first or second electrode set.

Claims

1. A sensor, comprising:

first and second electrode sets respectively disposed upon a planar support surface and a proof mass that is compliantly displaceable along a first axis substantially parallel to the planar support surface; and

a first barrier disposed on the planar support around the first electrode set having a height less than a gap between the planar support and the proof mass to mitigate particle migration into the first or second electrode sets.

2. The sensor of claim 1, further comprising:

at least one trench formed in the planar support around the first barrier.

3. The sensor of claim 1, further comprising:

a second barrier disposed on the proof mass outside of the second electrode set having a height less than the gap between the planar support and the proof mass.

4. The sensor of claim 3, further comprising:

at least one trench formed in the proof mass around the second barrier.

5. The sensor of claim 1, wherein the first barrier comprises:

a first elongated segment set disposed on the planar support surrounding the first electrode set; and

a second elongated segment set disposed on the planar support spaced apart from and surrounding the first elongated segment set.

6. The sensor of claim 4, wherein at least one of the first or second elongated segment set includes at least one break between segments.

7. A method of making a sensor, comprising:

forming a substrate having a first electrode set disposed thereon;

forming a proof mass having a second electrode set, the proof mass being compliantly displaceable along a first axis substantially parallel to the substrate; and

forming a first barrier on the substrate around the first electrode set having a height less than a gap between the substrate and the proof mass to mitigate particle migration into the first or second electrode sets.

8. The method of claim 7, further comprising:

forming at least one trench in the substrate around the first barrier.

9. The method of claim 7, further comprising:

forming a second barrier on the proof mass outside of the second electrode set having a height less than the gap between the planar support and the proof mass.

10. The method of claim 9, further comprising:

forming at least one trench in the proof mass around the second barrier.

11. The method of claim 7, wherein the first barrier comprises:

a first elongated segment set disposed on the planar support surrounding the first electrode set; and

a second elongated segment set disposed on the planar support spaced apart from and surrounding the first elongated segment set.

12. The method of claim 10, wherein at least one of the first or second elongated segment set includes at least one break between segments.