High performance sensors and methods for forming the same

• US 8,187,902 B2
• Filed: 07/09/2008
• Issued: 05/29/2012
• Est. Priority Date: 07/09/2008
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Weinberg, Marc S., Bancu, Mirela G., Bickford, James A., Bernstein, Jonathan J., Elliott, Richard
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US12/170,190
• Publication Number:
  US 20100005884A1
• Time in Patent Office: 1,420 Days
• Field of Search: 438/50, 735/041.2, 735/041.4, 735/143.2
• US Class Current: 438/50
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: Y10T 156/1039 Surface deformation only of sandwich or lamina [e.g., embossed panels]
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]

Abstract

A sensor includes a proof mass suspended by a suspension beam, the suspension beam having a thickness less than a thickness of the proof mass.

Claims

1. A method of fabricating a sensor, the method comprising:

forming a first recess in a first surface of a first substrate;

bonding a portion of the first surface of the first substrate to a second substrate;

forming a second recess in a second surface of the first substrate, the first substrate consisting essentially of a single material between the first and second surfaces, and the second recess being disposed over the first recess, thereby forming a suspension beam located between the first and second recesses, the suspension beam suspending a proof mass over the second substrate;

forming a third recess in the first surface of the first substrate; and

forming a fourth recess in the second surface of the first substrate, thereby forming a stationary comb finger located between the third and fourth recesses and disposed over the second substrate.

2. The method of claim 1, wherein a thickness of the suspension beam is less than a thickness of the proof mass.

3. The method of claim 2, wherein a difference between the thickness of the proof mass and the thickness of the suspension beam is approximately equal to an aggregate depth of the first and second recesses.

4. The method of claim 1, wherein a depth of the first recess is approximately equal to a depth of the second recess.

5. The method of claim 1, wherein a thickness of the stationary comb finger is less than a thickness of a mobile comb finger disposed on an edge of the proof mass.

6. The method of claim 1, wherein a depth of the third recess is approximately equal to a depth of the fourth recess.

7. The method of claim 1, wherein the first and third recesses are formed substantially simultaneously and the second and fourth recesses are formed substantially simultaneously.