Semiconductor acceleration sensor and its fabrication method

• US 5,665,914 A
• Filed: 02/09/1996
• Issued: 09/09/1997
• Est. Priority Date: 05/02/1995
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yamamoto, Masahiro
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US08/598,975
• Time in Patent Office: 578 Days
• Field of Search: 73/514.16, 73/514.29, 73/514.33, 73/514.36, 73/514.37, 73/514.38
• US Class Current: 73/514.16
• CPC Class Codes: G01P 1/006 used for thermal compensation
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 2015/0828 the mass being of the paddle type being suspended at one of its longitudinal ends

Abstract

The invention provides a high-reliability inexpensive semiconductor acceleration sensor requiring no special material for a pedestal, making is possible to decrease the number of materials and the number of assembly steps. A semiconductor acceleration sensor includes a circuit substrate having a thick-film circuit including at least a circuit conductor and an insulating layer, a pedestal on the circuit substrate, a flexible acceleration detecting beam supported by the pedestal and deflecting in response to acceleration, a sensor device on the acceleration detecting beam converting deflection of the acceleration detecting beam into an electrical signal, and a conductor connecting the sensor device with the thick-film circuit wherein the pedestal is the same material as at least one of the circuit conductor and the insulating layer.

Claims

1. A semiconductor acceleration sensor comprising:

a circuit substrate;

a thick film circuit including at least a circuit conductor and a glass insulating layer disposed on said circuit substrate;

a pedestal disposed on said circuit substrate;

a flexible acceleration detecting beam mounted on said pedestal and deflecting in response to an acceleration acting on said beam;

a sensor device disposed on said acceleration detecting beam for converting deflection of said acceleration detecting beam into an electrical signal; and

a sensor conductor electrically connecting said sensor device to said thick film circuit, wherein said pedestal includes at least one of said circuit conductor and said glass insulating layer.

2. A semiconductor acceleration sensor comprising;

a circuit substrate;

a thick film circuit including at least a circuit conductor and an insulating layer disposed on said circuit substrate;

a pedestal disposed on said circuit substrate;

a flexible acceleration detecting beam mounted on said pedestal and deflecting in response to an acceleration acting on said beam;

a sensor device disposed on said acceleration detecting beam for converting deflection of said acceleration detecting beam into an electrical signal; and

a sensor conductor electrically connecting said sensor device to said thick film circuit, wherein said pedestal includes both of said circuit conductor and said insulating layer.

3. The semiconductor acceleration sensor of claim 2 wherein said insulating layer is a glass layer.

4. A method of fabricating a semiconductor acceleration sensor comprising:

printing a thick film circuit including at least a circuit conductor and a glass insulating layer, simultaneously forming a pedestal made of the same materials as at least one of said circuit conductor and said glass insulating layer on a circuit substrate;

securing to said glass insulating layer a flexible acceleration detecting beam including a sensor device for converting deflection of said flexible acceleration detecting beam into an electrical signal, said flexible acceleration detecting beam deflecting in response to acceleration acting on said beam; and

electrically connecting said sensor device to said thick film circuit.