Method of manufacturing a sensor detecting a physical action as an applied force

• US 6,185,814 B1
• Filed: 02/06/1998
• Issued: 02/13/2001
• Est. Priority Date: 12/28/1989
• Status: Expired due to Fees

• Current Assignee: Kazuhiro Okada
• Original Assignee: Kazuhiro Okada
• Inventors: Okada, Kazuhiro
• Primary Examiner(s): Young, Lee
• Assistant Examiner(s): SMITH, SEAN PRENTISS
• Application Number:
  US09/019,978
• Time in Patent Office: 1,103 Days
• Field of Search: 296/211, 296/101, 296/21, 296/20, 738/620.41, 738/620.42, 738/620.43, 738/626.8, 737/18, 737/21, 737/24, 735/18, 735/17.R, 738/626.26, 73D/IG.4, 361/283
• US Class Current: 29/621.1
• CPC Class Codes: G01L 1/148 using semiconductive material, e.g. silicon
• CPC Class Codes: G01L 1/18 using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
• CPC Class Codes: G01L 25/00 Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
• CPC Class Codes: G01L 5/162 of piezoresistors
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 2015/084 the mass being suspended at more than one of its sides, e.g. membrane-type suspension, so as to permit multi-axis movement of the mass
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups
• CPC Class Codes: Y10T 29/49103 Strain gauge making

Abstract

A sensor comprises a semiconductor pellet (10) including a working portion (11) adapted to undergo action of a force, a fixed portion (13) fixed on the sensor body, and a flexible portion (13) having flexibility formed therebetween, a working body (20) for transmitting an exterted force to the working portion, and detector means (60-63) for transforming a mechanical deformation produced in the semiconductor pellet to an electric signal to thereby detect a force exerted on the working body as an electric signal. A signal processing circuit is applied to the sensor. This circuit uses analog multipliers (101-109) and analog adders/subtracters (111-113), and has a function to cancel interference produced in different directions. Within the sensor, two portions (E3, E4-E8) located at positions opposite to each other and producing a displacement therebetween by action of a force are determined. By exerting a coulomb force between both the portions, the test of the sensor is carried out. Further, a pedestal (21, 22) is provided around the working body (20). The working body and the pedestal are located with a predetermined gap or spacing therebetween. A displacement of the working body is caused to limitatively fall within a predetermined range corresponding to the spacing. The working body and the pedestal are provided by cutting a same common substrate (350, 350′)

Claims

1. A method of manufacturing a sensor for detecting a physical action as an applied force, said method comprising the steps of:

providing a first substrate having opposite first and second surfaces;

defining a first area, a second area and a third area on said first surface of said first substrate,said second area having a shape of a square ring with a width, said first area being located inside said second area and said third area being located outside said second area;

providing a detection element within said second area on said first surface of said first substrate, said detection element being for detecting mechanical deformation of said first substrate in said second area; and

providing first, second, third and fourth grooves on said second surface of said first substrate, said first groove and said second groove being located along two opposite sides of said square ring and said third groove and said fourth groove being located along another two opposite sides of said square ring so that said grooves define parallel crosses for allowing said second area to flex under an applied force;

whereby to detect a physical action as said force applied to said first area or said third area.

2. A method of manufacturing a sensor according to claim 1, said method further comprising the steps of:

preparing a second substrate;

connecting a first surface of the second substrate to the second surface, on which the four grooves are provided, of the first substrate; and

cutting said second substrate to thereby form a working body connected to the first area of the first substrate and a pedestal connected to the third area of the first substrate, said working body and said pedestal being comprised of a portion of said second substrate;

thus to manufacture a sensor which detects a physical action as a force applied to said working body which is supported by said pedestal.

3. A method of manufacturing a sensor according to claim 1, said method further comprising the steps of:

preparing a second substrate;

connecting a first surface of the second substrate to the second surface, on which the four grooves are provided, of the first substrate; and

cutting said second substrate to thereby form a working body connected to the third area of the first substrate and a pedestal connected to the first area of the first substrate, said working body and said pedestal being comprised of a portion of said second substrate;

thus to manufacture a sensor which detects a physical action as a force applied to said working body which is supported by said pedestal.

4. A method of manufacturing a sensor according to claim 1, wherein a resistance element is provided on the first substrate as a detection element.

5. A method of manufacturing sensors detecting a physical action as an applied force, said method comprising the steps of:

preparing a first substrate;

defining a plurality of unit areas on the first substrate;

defining a first area, a second area and a third area within the respective unit areas on the first substrate, the respective second areas having a shape of a square ring with a width, the respective first areas being located inside the respective second areas and the respective third areas being located outside the respective second areas;

providing detection elements within the respective second areas on a first surface of the first substrate, said detection elements detecting mechanical deformation of said first substrate in the respective second areas;

providing a plurality of grooves on a second surface of the first substrate extending across the substrate so that respective four grooves are constituted within the respective unit areas wherein a first groove and a second groove are located along two opposite sides of said square ring and a third groove and a fourth groove are located along the other two opposite sides of said square ring so that parallel crosses are constituted by the respective four grooves which allow the respective second areas to have flexibility; and

cutting off said first substrate to separate the respective unit areas;

thus to manufacture sensors made of the respective unit areas which detect a physical action as a force applied to the first area or the third area.

6. A method of manufacturing sensors according to claim 5, said method further comprising the steps of:

preparing a second substrate;

connecting a first surface of the second substrate to the second surface, on which the grooves are provided, of the first substrate; and

cutting said second substrate to thereby form respective working bodies connected to the respective first areas of the first substrate and respective pedestals connected to the respective third areas of the first substrate, said working bodies and said pedestals being comprised of portions of said second substrate;

wherein said first substrate is cut off along with said second substrate connected thereto to separate the respective unit areas;

thus to manufacture sensors which detect a physical action as a force applied to the working body which is supported by the pedestal.

7. A method of manufacturing sensors according to claim 5, said method further comprising the steps of:

preparing a second substrate;

connecting a first surface of the second substrate to the second surface, on which the grooves are provided, of the first substrate; and

cutting said second substrate to thereby form respective working bodies connected to the respective third areas of the first substrate and respective pedestals connected to the respective first areas of the first substrate, said working bodies and said pedestals being comprised of portions of said second substrate;

wherein said first substrate is cut off along with said second substrate connected thereto to separate the respective unit areas;

thus to manufacture sensors which detect a physical action as a force applied to the working body which is supported by the pedestal.

8. A method of manufacturing sensors according to claim 5, wherein resistance elements are provided on the first substrate as section elements.