Wafer bonding method for use in making a mems gyroscope

Abstract

A MEMS gyroscope is disclosed herein, wherein the MEMS gyroscope comprised a magnetic sensing mechanism on a magnetic sensor wafer and a magnetic source on a MEMS wafer that further comprises a proof-mass. The magnetic sensor wafer and MEMS wafer are bonded through a bonding mechanism that comprises a hearting mechanism.

We claim: 
     
         1 . A MEMS gyroscope, comprising:
 a first substrate having a movable portion that is movable in response to an external angular velocity, said movable portion comprising a magnetic source for generating magnetic field;   a second substrate having a magnetic sensor for detecting the magnetic field from said magnetic source; and   a bonding structure for bonding the first and second wafer with a predetermined distance, said bonding structure comprising:
 a heating mechanism for generating heating; and 
 a bonding material. 
   
     
     
         2 . The MEMS gyroscope of  claim 1 , wherein the bonding structure further comprises an insulating layer between the heating mechanism and the bonding material. 
     
     
         3 . The MEMS gyroscope of  claim 2 , wherein the bonding material comprises a metal or a metal alloy. 
     
     
         4 . The MEMS gyroscope of  claim 2 , wherein the magnetic sensor comprises a giant-magnetic-resistor. 
     
     
         5 . The MEMS gyroscope of  claim 2 , wherein the magnetic sensors comprises a spin-valve structure. 
     
     
         6 . The MEMS gyroscope of  claim 2 , wherein the magnetic sensors comprises a tunnel-magnetic-resistor. 
     
     
         7 . The MEMS gyroscope of  claim 2 , wherein the magnetic sensors comprises a magnetic pickup coil that is an element of a fluxgate.