Hermetically sealed semiconductor inertial sensor

• US 6,289,732 B1
• Filed: 12/09/1997
• Issued: 09/18/2001
• Est. Priority Date: 12/24/1996
• Status: Expired due to Term

• Current Assignee: SGS-Thomson Microelectronics, S.R.L. (STMicroelectronics NV)
• Original Assignee: Scs-Thomson Microelectronics SA
• Inventors: Murari, Bruno, Ferrari, Paolo, Vigna, Benedetto
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US08/987,255
• Time in Patent Office: 1,379 Days
• Field of Search: 734/93, 735/041.5, 735/141.5, 735/141.6, 735/142.4, 735/142.9, 735/143.2, 735/143.3, 735/143.4, 735/143.6, 735/143.7, 735/143.8, 734/31, 738/665, 73/13.8, 737/21, 737/18, 737/27, 257/704
• US Class Current: 73/493
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/0802 Details

Abstract

An inertial sensor has a sensing element formed on one surface of a chip of semiconductor material and which is movable with respect to the chip. The sensing element is enclosed in a sealed hollow structure, in which the hollow structure includes a metal wall disposed on the surface around the sensing element, and a closure plate fixed to the wall.

Claims

1. A monolithic integrated circuit inertial sensor comprising:

a monolithic integrated circuit substrate comprising semiconductor material;

an inertial sensing element on a surface of said substrate and movable with respect thereto; and

a hollow structure enclosing said inertial sensing element, said hollow structure comprising

a metal wall disposed on the surface of said substrate around said inertial sensing element, said metal wall having a height at least as great as a height of said inertial sensing element, and

a closure plate fixed to said metal wall.

2. A monolithic intergrated circuit inertial sensor according to claim 1, wherein said metal wall compreses a welding alloy.

3. A monolithic intergrated circuit inertial sensor according to claim 1, wherein said closure plate comprises a metal material.

4. A monolithic intergrated circuit inertial sensor according to claim 1, wherein said closure plate comprises a polymeric material.

5. A monolithic intergrated circuit inertial sensor according to claim 1, further comprising a processing circuit formed in said substrate.

6. A monolithic intergrated circuit inertial sensor according to claim 1, further comprising a plastic container encapsulating said substrate, said sensing element, and said hollow structure.

7. A monolithic integrated circuit inertial sensor comprising:

a monolithic integrated circuit substrate comprising semiconductor material;

an inertial sensing element on a surface of said substrate and movable with respect thereto;

a hollow structure enclosing said inertial sensing element and connected to said substrate, said hollow structure comprising

a wall disposed on the surface of said substrate about said inertial sensing element, and

a closure plate on said wall; and

a processing circuit in said substrate and connected to said inertial sensing element.

8. A monolithic intergrated circuit inertial sensor according to claim 7, wherein said wall comprises metal.

9. A monolithic intergrated circuit inertial sensor according to claim 7, wherein said wall comprises a welding alloy.

10. A monolithic intergrated circuit inertial sensor according to claim 7, wherein said closure plate comprises a metal material.

11. A monolithic intergrated circuit inertial sensor according to claim 7, wherein said closure plate comprises a polymeric material.

12. A monolithic intergrated circuit inertial sensor according to claim 7, further comprising a plastic container encapsulating said substrate, said sensing element, and said hollow structure.