Wafer encapsulated microelectromechanical structure and method of manufacturing same

• US 20070170531A1
• Filed: 11/06/2006
• Published: 07/26/2007
• Est. Priority Date: 01/20/2006
• Status: Abandoned Application

• Current Assignee: Aaron Partridge, Markus Lutz, Pavan Gupta
• Original Assignee: Aaron Partridge, Markus Lutz, Pavan Gupta
• Inventors: Partridge, Aaron, Lutz, Markus, Gupta, Pavan
• Application Number:
  US11/593,428
• Publication Number:
  US 20070170531A1
• Time in Patent Office: Days
• US Class Current: 257/415
• CPC Class Codes: B81B 2201/0271 Resonators; ultrasonic resonators
• CPC Class Codes: B81B 2203/0315 Cavities
• CPC Class Codes: B81B 2203/04 Electrodes
• CPC Class Codes: B81B 2207/07 Interconnects
• CPC Class Codes: B81B 7/0035 for maintaining a controlled atmosphere inside of the chamber containing the MEMS
• CPC Class Codes: B81B 7/0058 for protecting against damages due to external chemical or mechanical influences, e.g. shocks or vibrations
• CPC Class Codes: B81B 7/007 Interconnections between the MEMS and external electrical signals
• CPC Class Codes: B81C 1/00269 Bonding of solid lids or wafers to the substrate
• CPC Class Codes: B81C 1/00277 for maintaining a controlled atmosphere inside of the cavity containing the MEMS
• CPC Class Codes: B81C 1/00301 Connecting electric signal lines from the MEMS device with external electrical signal lines, e.g. through vias
• CPC Class Codes: B81C 2201/0171 Doping materials
• CPC Class Codes: B81C 2203/031 Anodic bondings
• CPC Class Codes: B81C 2203/036 Fusion bonding
• CPC Class Codes: B81C 2203/037 Thermal bonding techniques not provided for in B81C2203/035 - B81C2203/036
• CPC Class Codes: B81C 2203/038 Bonding techniques not provided for in B81C2203/031 - B81C2203/037
• CPC Class Codes: H01L 23/051 another lead being formed by a cover plate parallel to the base plate, e.g. sandwich type
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H10N 30/306 Cantilevers

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.

Claims

1-30. -30. (canceled)

31. A system comprising:

a first substrate including carbon, polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, and/or gallium arsenide;

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 the second substrate includes carbon, polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, and/or gallium arsenide; and

circuitry disposed in or on the second substrate.

32. The system of claim 31 wherein the circuitry is formed in the second substrate after the second substrate is bonded to the first substrate.

33. The system of claim 31 wherein the circuitry is formed in the second substrate before the second substrate is bonded to the first substrate.

34. The system of claim 31 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.

35. The system of claim 31 further including a contact having:

a first portion of the contact (i) formed from a portion of the first substrate and (ii) at least a portion thereof being disposed outside the chamber; and

a second portion of the contact formed from a portion of the second substrate;

wherein the contact is electrically coupled to the circuitry.

36. The system of claim 31 wherein the circuitry generates clock signals from an output signal of the microelectromechanical structure.

37. The system of claim 36 wherein the circuitry adjusts, compensates, corrects and/or controls the frequency and/or phase compensation of the output signal of the microelectromechanical structure.

38. The system of claim 37 wherein the circuitry includes one or more phase locked loops, delay locked loops, digital synthesizer, frequency synthesizer, fractional synthesizer, numerically controlled oscillator, and/or frequency locked loops.

39. The system of claim 31 wherein the microelectromechanical device is a portion of an accelerometer, gyroscope, transducer, filter and/or resonator.

40. The system of claim 31 wherein the microelectromechanical structure includes more than one mechanical structure.

41. The system of claim 40 wherein at least one of the mechanical structures is a filter, resonator, accelerometer, gyroscope, pressure sensor, strain sensor, tactile sensor, magnetic sensor or temperature sensor.

42. A system comprising:

a first substrate;

a second substrate, wherein the second substrate is bonded to the first substrate and includes carbon, polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, and/or gallium arsenide;

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 the third substrate includes carbon, polycrystalline silicon, porous polycrystalline silicon, amorphous silicon, silicon carbide, silicon/germanium, germanium, and/or gallium arsenide; and

circuitry disposed in or on the third substrate.

43. The system of claim 42 wherein the circuitry is formed in the second substrate after the second substrate is bonded to the first substrate.

44. The system of claim 42 wherein the circuitry is formed in the second substrate before the second substrate is bonded to the first substrate.

45. The system of claim 42 further including a contact having:

a first portion of the contact (i) formed from a portion of the second substrate and (ii) at least a portion thereof being disposed outside the chamber; and

a second portion of the contact formed from a portion of the third substrate;

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.

46. The system of claim 42 further including:

a contact having;

a first portion of the contact (i) formed from a portion of the second substrate and (ii) at least a portion thereof being disposed outside the chamber; and

a second portion of the contact formed from a portion of the third substrate; and

a trench disposed in the third substrate and around at least a portion of the second portion of the contact.

47. The system of claim 46 wherein the trench includes an insulation material disposed therein to electrically isolate the second portion of the contact from the third substrate.

48. The system of claim 46 further including an isolation region disposed in the second substrate such that the trench is aligned with and juxtaposed to the isolation region.

49. The system of claim 48 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.

50. The system of claim 42 further including

a contact having:

a first portion of the contact (i) formed from a portion of the second substrate and (ii) at least a portion thereof being disposed outside the chamber; and

a second portion of the contact formed from a portion of the third substrate; and

an isolation region, disposed in the first substrate such that a first portion of the contact is aligned with and juxtaposed to the isolation region.

51. The system of claim 42 further including:

a contact having;

a first portion of the contact (i) formed from a portion of the second substrate and (ii) at least a portion thereof being disposed outside the chamber; and

a second portion of the contact formed from a portion of the third substrate;

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.

52. The system of claim 51 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.

53. The system of claim 52 further including a trench, disposed in the third substrate and around at least a portion of the second portion of the contact.

54. The system of claim 53 wherein the trench includes an insulation material disposed therein to electrically isolate the second portion of the contact from the third substrate.

55. The system of claim 54 wherein the trench is aligned with and juxtaposed to the second isolation region.

56. The system of claim 42 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.

57. The system of claim 42 wherein the circuitry generates clock signals from an output signal of the microelectromechanical structure.

58. The system of claim 57 wherein the circuitry adjusts, compensates, corrects and/or controls the frequency and/or phase compensation of the output signal of the microelectromechanical structure.

59. The system of claim 58 wherein the circuitry includes one or more phase locked loops, delay locked loops, digital synthesizer, frequency synthesizer, fractional synthesizer, numerically controlled oscillator, and/or frequency locked loops.

60. The system of claim 59 wherein the microelectromechanical device is a portion of an accelerometer, gyroscope, transducer, filter and/or resonator.

61. The system of claim 42 wherein the microelectromechanical structure includes more than one mechanical structure.

62. The system of claim 61 wherein at least one of the mechanical structures is a filter, resonator, accelerometer, gyroscope, pressure sensor, strain sensor, tactile sensor, magnetic sensor or temperature sensor.