Wafer encapsulated microelectromechanical structure and method of manufacturing same

Abstract

There are many inventions described and illustrated herein. In one aspect, the present inventions relate to devices, systems and/or methods of encapsulating and fabricating electromechanical structures or elements, for example, accelerometer, gyroscope or other transducer (for example, pressure sensor, strain sensor, tactile sensor, magnetic sensor and/or temperature sensor), filter or resonator. The fabricating or manufacturing microelectromechanical systems of the present invention, and the systems manufactured thereby, employ wafer bonding encapsulation techniques.

1 . A microelectromechanical device comprising:
 a first substrate;   a chamber;   a microelectromechanical structure, wherein the microelectromechanical structure is (i) formed from a portion of the first substrate and (ii) at least partially disposed in the chamber;   a second substrate, bonded to the first substrate, wherein a surface of the second substrate forms a wall of the chamber; and   a contact, wherein:
 a first portion of the contact is (i) formed from a portion of the first substrate and (ii) at least a portion thereof is disposed outside the chamber; and 
 a second portion of the contact is formed from a portion of the second substrate. 
   
   
   
       2 . The microelectromechanical device of  claim 1  wherein the second substrate includes polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, or gallium arsenide. 
   
   
       3 . The microelectromechanical device of  claim 2  wherein the first substrate includes polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, or gallium arsenide. 
   
   
       4 . The microelectromechanical device of  claim 2  wherein:
 the first portion of the contact is a semiconductor material having a first conductivity;   the second substrate is a semiconductor material having a second conductivity; and   the second portion of the contact is a semiconductor material having the first conductivity.   
   
   
       5 . The microelectromechanical device of  claim 4  wherein the second portion of the contact is a polycrystalline or monocrystalline silicon that is counterdoped to include the first conductivity. 
   
   
       6 . The microelectromechanical device of  claim 1  further including a trench, disposed in the second substrate and around at least a portion of the second portion of the contact. 
   
   
       7 . The microelectromechanical device of  claim 6  wherein the trench includes a first material disposed therein to electrically isolate the second portion of the contact from the second substrate. 
   
   
       8 . The microelectromechanical device of  claim 6  wherein the first material is an insulation material. 
   
   
       9 . The microelectromechanical device of  claim 1  wherein the first substrate is an semiconductor on insulator substrate. 
   
   
       10 . The microelectromechanical device of  claim 1  wherein the first and second substrates are bonded using fusion bonding, anodic-like bonding, silicon direct bonding, soldering, thermo compression, thermo-sonic, laser bonding and/or glass reflow. 
   
   
       11 . A microelectromechanical device comprising:
 a first substrate;   a second substrate, wherein the second substrate is bonded to the first substrate;   a chamber;   a microelectromechanical structure, wherein the microelectromechanical structure is (i) formed from a portion of the second substrate and (ii) at least partially disposed in the chamber;   a third substrate, bonded to the second substrate, wherein a surface of the third substrate forms a wall of the chamber; and   a contact, wherein:
 a first portion of the contact is (i) formed from a portion of the second substrate and (ii) at least a portion thereof is disposed outside the chamber; and 
 a second portion of the contact is formed from a portion of the third substrate. 
   
   
   
       12 . The microelectromechanical device of  claim 11  wherein the second substrate includes polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, or gallium arsenide. 
   
   
       13 . The microelectromechanical device of  claim 12  wherein the third substrate includes polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, or gallium arsenide. 
   
   
       14 . The microelectromechanical device of  claim 12  wherein:
 the first portion of the contact is a semiconductor material having a first conductivity;   the third substrate is a semiconductor material having a second conductivity; and   the second portion of the contact is a semiconductor material having the first conductivity.   
   
   
       15 . The microelectromechanical device of  claim 14  wherein the second portion of the contact is a polycrystalline or monocrystalline silicon that is counterdoped to include the first conductivity. 
   
   
       16 . The microelectromechanical device of  claim 17  further including a trench, disposed in the third substrate and around at least a portion of the second portion of the contact. 
   
   
       17 . The microelectromechanical device of  claim 16  wherein the trench includes a first material disposed therein to electrically isolate the second portion of the contact from the third substrate. 
   
   
       18 . The microelectromechanical device of  claim 16  wherein the first material is an insulator material. 
   
   
       19 . The microelectromechanical device of  claim 16  further including an isolation region disposed in the second substrate such that the trench is aligned with and juxtaposed to the isolation region. 
   
   
       20 . The microelectromechanical device of  claim 19  wherein:
 the first portion of the contact is a semiconductor material having a first conductivity;   the isolation region is a semiconductor material having a second conductivity; and   the second portion of the contact is a semiconductor material having the first conductivity.   
   
   
       21 . The microelectromechanical device of  claim 20  wherein the trench includes a first material disposed therein to electrically isolate the second portion of the contact from the second substrate. 
   
   
       22 . The microelectromechanical device of  claim 16  wherein the first material is a semiconductor material having the second conductivity. 
   
   
       23 . The microelectromechanical device of  claim 11  further including an isolation region, disposed in the first substrate such that the first portion of the contact is aligned with and juxtaposed to the isolation region. 
   
   
       24 . The microelectromechanical device of  claim 11  further including:
 a first isolation region, disposed in the first substrate such that the first portion of the contact is aligned with and juxtaposed to the first isolation region; and   a second isolation region, disposed in the second substrate such that the second portion of the contact is aligned with and juxtaposed to the second isolation region.   
   
   
       25 . The microelectromechanical device of  claim 24  wherein:
 the first and second portions of the contact are semiconductor materials having a first conductivity; and   the first and second isolation regions are semiconductor materials having the second conductivity.   
   
   
       26 . The microelectromechanical device of  claim 25  further including a trench, disposed in the third substrate and around at least a portion of the second portion of the contact. 
   
   
       27 . The microelectromechanical device of  claim 26  wherein the trench includes a first material disposed therein to electrically isolate the second portion of the contact from the third substrate. 
   
   
       28 . The microelectromechanical device of  claim 27  wherein the trench is aligned with and juxtaposed to the second isolation region. 
   
   
       29 . The microelectromechanical device of  claim 28  wherein the first material is an insulator material. 
   
   
       30 . The microelectromechanical device of  claim 11  wherein the second and third substrates are bonded using fusion bonding, anodic-like bonding, silicon direct bonding, soldering, thermo compression, thermo-sonic, laser bonding and/or glass reflow.