Claims
- 1. An apparatus for detecting an applied force comprising:
a housing; a substrate comprising a semiconducting material and defining a frame, said frame fixed to said housing; a reaction mass defined by said substrate, said reaction mass disposed external to said frame and rotatably attached to said frame; an active layer of semiconducting material comprising one or more vibratory force transducers mechanically coupled to said frame and to said reaction mass for detecting a force applied thereto; and an insulating layer formed between said substrate and said active layer to insulate at least a portion of said vibratory transducers from said substrate.
- 2. The apparatus of claim 1 wherein said frame includes an internal frame member and a cover fixed to said internal frame member.
- 3. The apparatus of claim 2 wherein:
said substrate is formed essentially planar; and said reaction mass includes an internal passage formed in said substrate.
- 4. The apparatus of claim 3 wherein said internal frame member is disposed within said internal passage in said reaction mass.
- 5. The apparatus of claim 4 wherein said cover is disposed parallel with and spaced away from said internal frame member.
- 6. The apparatus of claim 5 further comprising a pedestal portion extending between said cover and said internal frame member.
- 7. The apparatus of claim 6 wherein said substrate is formed of a material selected from the group consisting of quartz and silicon.
- 8. The apparatus of claim 1 wherein said reaction mass includes an internal pendulum portion and an external cover fixed to said pendulum portion.
- 9. The apparatus of claim 1 wherein:
said substrate is formed essentially planar; and said frame includes an internal passage formed therein.
- 10. The apparatus of claim 9 wherein said internal pendulum portion is disposed within said internal passage.
- 11. The apparatus of claim 10 wherein said cover is disposed parallel with and spaced away from said internal pendulum portion.
- 12. The apparatus of claim 11 further comprising pedestal portion extending between said cover and said internal pendulum portion.
- 13. The apparatus of claim 1 wherein said reaction mass comprises an external pendulum portion and a cover fixed to said pendulum portion.
- 14. The apparatus of claim 13 wherein said frame comprises an internal frame member spaced away from said housing and a pedestal portion extending between said housing and said internal frame member.
- 15. The apparatus of claim 14 wherein said cover includes a substantially planar portion disposed essentially parallel with said substrate and spaced away from said internal frame member.
- 16. The apparatus of claim 15 wherein said cover includes a passage formed therein, said pedestal portion extending through said passage.
- 17. An apparatus for detecting an applied force comprising:
a housing; an essentially planar substrate comprising a semiconducting material; a frame defined by said substrate and fixed to said housing, said frame comprising an internal frame member and a cover fixed to said internal frame member; a reaction mass defined by said substrate, said reaction mass rotatably attached externally to said internal frame member; an active layer of semiconducting material comprising one or more vibrating beam force sensors mechanically coupled between said frame and to said reaction mass for measuring a displacement of said reaction mass; and an insulating layer formed between said substrate and said active layer to insulate at least a portion of said vibrating beam force sensors from said substrate.
- 18. The apparatus of claim 17, wherein said internal frame member and said cover are substantially planar and said internal frame member is positioned parallel to and spaced away from said cover; and
further comprising a pedestal portion extending between said internal frame member and said cover.
- 19. The apparatus of claim 18, wherein said reaction mass includes a passage formed therein.
- 20. The apparatus of claim 19, wherein said internal frame member is nominally disposed within said passage in said reaction mass and rotatably fixed to a inner surface of said passage.
- 21. An apparatus for detecting an applied force comprising:
a housing; a substrate comprising a semiconducting material and defining a frame formed with a passage, said frame fixed to said housing; a reaction mass defined by said substrate, said reaction mass comprising:
a) first and second covers, said first cover substantially parallel with and spaced away from said second cover, and b) an internal pendulum portion suspended between said first and second covers, said internal pendulum portion positioned within said passage and rotatably suspended from said frame; an active layer of semiconducting material comprising one or more vibratory force transducers mechanically coupled to said frame and to said reaction mass for detecting a force applied thereto; and an insulating layer formed between said substrate and said active layer to insulate at least a portion of said vibratory transducers from said substrate.
- 22. The apparatus of claim 21 further comprising first and second pedestal portions, said first pedestal portion extending between a first side of said internal pendulum portion and said first cover and said second pedestal portion extending between a second side of said internal pendulum portion and said second cover.
- 23. The apparatus of claim 22 wherein said one or more vibratory force transducers comprises first and second vibrating beam force sensors extending between said support structure and said reaction mass plate.
- 24. An apparatus for detecting an applied force comprising:
a housing; a frame fixed to said housing, said frame formed of a substantially planar substrate comprising a semiconducting material and formed with a passage; a reaction mass formed of said substrate, said reaction mass comprising:
a) first and second substantially planar covers, said first cover substantially parallel with and spaced away from said second cover, and b) a substantially planar internal pendulum portion suspended between said first and second covers, said internal pendulum portion nominally positioned within said passage and rotatably attached said frame; an active layer of semiconducting material comprising one or more vibratory force transducers mechanically coupled to said frame and to said reaction mass for detecting a force applied thereto; and an insulating layer formed between said substrate and said active layer to insulate at least a portion of said vibratory transducers from said substrate.
- 25. The apparatus of claim 24 wherein said one or more vibratory force transducers comprises first and second vibrating beam force sensors extending between said frame and said internal pendulum portion.
- 26. An apparatus for detecting an applied force comprising:
a housing; a substrate comprising a semiconducting material and defining a reaction mass, said reaction mass comprising: a) an external pendulum portion formed with a passage, b) first and second covers, said covers attached to and spaced away from said external pendulum portion, and c) said external pendulum portion and said covers defining an internal cavity in said reaction mass; an internal frame member disposed within said cavity, said external pendulum portion rotatably attached to said internal frame member; a pedestal portion extending between said internal frame member and said housing; an active layer of semiconducting material comprising one or more vibratory force transducers mechanically coupled to said frame and to said reaction mass for detecting a force applied thereto; and an insulating layer formed between said substrate and said active layer to insulate at least a portion of said vibratory transducers from said substrate.
- 27. An accelerometer made from a process comprising:
applying an insulating layer between a semiconducting substrate and a semiconducting active layer; forming a frame and a reaction mass in the substrate such that the reaction mass is externally suspended from the frame by one or more flexures; fixing said frame to a housing; and forming one or more vibratory force transducers in the active layer such that the transducers are capable of detecting a force applied to the reaction mass.
- 28. The invention of claim 27 wherein said forming a frame and a reaction mass further comprises fixing a cover to said housing and fixing an internal frame member to said cover.
- 29. The invention of claim 28 wherein said reaction mass and said internal frame member are formed of a single substrate.
- 30. The invention of claim 29 wherein said reaction mass further comprises an internal pendulum portion and an external cover fixed to said pendulum portion.
- 31. The invention of claim 27 wherein said reaction mass comprises an external pendulum portion and a cover fixed to said external pendulum portion.
- 32. The invention of claim 31 wherein said frame includes an internal frame member and a pedestal portion extending between said internal frame member and said housing.
- 33. A method for detecting an applied force comprising:
rotatably suspending a reaction mass externally to a stationary frame on a semiconductor wafer; mechanically coupling at least one detector between said reaction mass and said frame for measuring a displacement of said reaction mass relative to said frame; and electrically insulating at least a portion of said detector from said semiconductor wafer.
- 34. The method of claim 33 further comprising fixing said stationary frame to a housing.
- 35. The method of claim 34 wherein said suspending a reaction mass further comprises fixing a cover to said housing and fixing an internal frame member to said cover.
- 36. The method of claim 34 wherein said reaction mass comprises an internal pendulum portion and an external cover fixed to said pendulum portion.
- 37. The method of claim 34 wherein said reaction mass comprises an external pendulum portion and a cover fixed to said external pendulum portion.
- 38. The method of claim 37 wherein said frame further comprises an internal frame member; and
wherein the method further comprises extending a pedestal portion between said internal frame member and said housing.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims benefit of the priority filing date of application Ser. No. 08/943,719, filed Oct. 3, 1997 which is continuation of Provisional application Ser. No. 60/044,034, filed Apr. 22, 1997, the complete disclosures of which are incorporated herein by reference. The present invention is a continuation of application Ser. No. 09/281,755, filed Mar. 30, 1999 which is a divisional of application Ser. No. 08/735,299, filed Oct. 22, 1996 which is a continuation-in-part of application Ser. No. 08/651,927, filed May 21, 1996.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60044034 |
Apr 1997 |
US |
Divisions (1)
|
Number |
Date |
Country |
Parent |
08735299 |
Oct 1996 |
US |
Child |
09281755 |
Mar 1999 |
US |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09281755 |
Mar 1999 |
US |
Child |
09398719 |
Sep 1999 |
US |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
08651927 |
May 1996 |
US |
Child |
08735299 |
Oct 1996 |
US |