Mems device

Abstract

A MEMS gyroscope is disclosed herein, wherein the MEMS gyroscope comprised a magnetic sensing mechanism and a magnetic source that is associated with the proof-mass. The magnetic sensing mechanism comprises multiple magnetic field sensors that are designated for sensing the magnetic field from a magnetic source so as to mitigate the problems caused by fabrication.

We claim: 
     
         1 . A MEMS gyroscope, comprising:
 a mass-substrate, comprising:
 a movable prof-mass; and 
 a magnetic source attached to the proof-mass such that the magnetic source is capable of moving with the proof-mass; and 
   a sensor substrate below the mass-substrate, comprising:
 a magnetic sensing mechanism for detecting a magnet field from the magnetic sensor, wherein the magnetic sensing mechanism is static relative to the magnetic source, wherein the magnetic sensing mechanism further comprising:
 a plurality of magnetic sensors associated with said magnetic source, wherein the plurality of magnetic sensors are deployed in the plane of the sensor substrate at different locations. 
 
   
     
     
         2 . The MEMS gyroscope of  claim 1 , wherein the magnetic source comprises a conductive wire to which current can be applied so as to generate a magnetic field. 
     
     
         3 . The MEMS gyroscope of  claim 1 , wherein the magnetic source comprises a magnetic nanoparticle. 
     
     
         4 . The MEMS gyroscope of  claim 2 , wherein conductive wire has a length along a length of at least one of the plurality of magnetic sensing mechanisms. 
     
     
         5 . The MEMS gyroscope of  claim 2 , wherein at least one of the plurality of magnetic sensors comprises a giant-magnetic-resistor. 
     
     
         6 . The MEMS gyroscope of  claim 2 , wherein at least one of the plurality of magnetic sensors comprises a spin-valve structure. 
     
     
         7 . The MEMS gyroscope of  claim 2 , wherein at least one of the plurality of magnetic sensors comprises a tunnel-magnetic-resistor. 
     
     
         8 . The MEMS gyroscope of  claim 2 , wherein at least one of the magnetic sensors comprises magnetic pickup coil that is an element of a fluxgate. 
     
     
         9 . The MEMS gyroscope of  claim 2 , wherein the magnetic sensors each has a geometric length and a width, wherein the geometric lengths of the magnetic sensors are substantially parallel, and are substantially parallel to the length of the conductive wire. 
     
     
         10 . The MEMS gyroscope of  claim 2 , wherein at least one of the magnetic sensors comprises a reference sensor and a signal sensor pair. 
     
     
         11 . A wafer assembly, comprising:
 a mass wafer comprising a plurality of mass dies, each mass die comprising
 a movable prof-mass; and 
 a magnetic source attached to the proof-mass such that the magnetic source is capable of moving with the proof-mass; and 
   a sensor wafer comprising a plurality of sensor dies, each sensor die comprising:
 a magnetic sensing mechanism for detecting a magnet field from the magnetic sensor, wherein the magnetic sensing mechanism is static relative to the magnetic source, wherein the magnetic sensing mechanism further comprising:
 a plurality of magnetic sensors associated with said magnetic source, wherein the plurality of magnetic sensors are deployed in the plane of the sensor substrate at different locations. 
 
   
     
     
         12 . The wafer assembly of  claim 11 , wherein the magnetic source comprises a conductive wire to which current can be applied so as to generate a magnetic field. 
     
     
         13 . The wafer assembly of  claim 11 , wherein the magnetic source comprises a magnetic nanoparticle. 
     
     
         14 . The wafer assembly of  claim 12 , wherein conductive wire has a length along a length of at least one of the plurality of magnetic sensing mechanisms. 
     
     
         15 . The wafer assembly of  claim 12 , wherein at least one of the plurality of magnetic sensors comprises a giant-magnetic-resistor. 
     
     
         16 . The wafer assembly of  claim 12 , wherein at least one of the plurality of magnetic sensors comprises a spin-valve structure. 
     
     
         17 . The wafer assembly of  claim 12 , wherein at least one of the plurality of magnetic sensors comprises a tunnel-magnetic-resistor. 
     
     
         18 . The wafer assembly of  claim 12 , wherein at least one of the magnetic sensors comprises magnetic pickup coil that is an element of a fluxgate. 
     
     
         19 . The wafer assembly of  claim 12 , wherein the magnetic sensors each has a geometric length and a width, wherein the geometric lengths of the magnetic sensors are substantially parallel, and are substantially parallel to the length of the conductive wire. 
     
     
         20 . The wafer assembly of  claim 12 , wherein at least one of the magnetic sensors comprises a reference sensor and a signal sensor pair.