Mechanical-Quality measuring device

Abstract

A mechanical-quantity measuring device capable of measuring a strain component in a specific direction with high precision is provided.

Description

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 is a schematic view showing the outline of a mechanical-quantity measuring device according to a first embodiment of the present invention;

FIG. 2 is a view showing an example of how to use in the first embodiment of the present invention;

FIG. 3 is a view showing a connecting state of diffusion resistors composing a bridge circuit of the mechanical-quantity measuring device according to the first embodiment of the present invention;

FIG. 4 is a schematic view showing the detail of the mechanical-quantity measuring device according to the first embodiment of the present invention;

FIG. 5 is a schematic view showing a sectional structure of the mechanical-quantity measuring device according to the first embodiment of the present invention;

FIG. 6 is a schematic view showing the detail of the mechanical-quantity measuring device according to the first embodiment of the present invention;

FIG. 7 is a schematic view showing the detail of a mechanical-quantity measuring device according to a second embodiment of the present invention;

FIG. 8 is a schematic view showing the detail of a mechanical-quantity measuring device according to a second embodiment of the present invention;

FIG. 9 is a schematic view showing the detail of the mechanical-quantity measuring device according to the second embodiment of the present invention;

FIG. 10 is a schematic view showing the detail of the mechanical-quantity measuring device according to the second embodiment of the present invention;

FIG. 11 is a schematic view showing the detail of the mechanical-quantity measuring device according to the second embodiment of the present invention;

FIG. 12 is a schematic view showing the detail of a mechanical-quantity measuring device according to a third embodiment of the present invention;

FIG. 13 is a view showing a connecting state of the diffusion resistors composing a bridge circuit of the mechanical-quantity measuring device according to the third embodiment of the present invention;

FIG. 14 is a block diagram showing an example of structure of the mechanical-quantity measuring device according to the third embodiment of the present invention;

FIG. 15 is a schematic view showing the detail of a mechanical-quantity measuring device according to a fourth embodiment of the present invention;

FIG. 16 is a block diagram showing an example of the structure of the mechanical-quantity measuring device according to the fourth embodiment of the present invention;

FIG. 17 is a schematic view showing the detail of a mechanical-quantity measuring device according to a fifth embodiment of the present invention;

FIG. 18 is a schematic view showing the detail of the mechanical-quantity measuring device according to the fifth embodiment of the present invention;

FIG. 19 is a view showing an operation flow of the mechanical-quantity measuring device according to the fifth embodiment of the present invention;

FIG. 20 is a schematic view showing the detail of a mechanical-quantity measuring device according to a sixth embodiment of the present invention;

FIG. 21 is a schematic view showing the detail of a mechanical-quantity measuring device according to a seventh embodiment of the present invention;

FIG. 22 is a schematic view showing an example of an amplifier circuit according to the seventh embodiment of the present invention;

FIG. 23 is a schematic view showing the detail of a mechanical-quantity measuring device according to an eighth embodiment of the present invention;

FIG. 24 is a schematic view showing the detail of a mechanical-quantity measuring device according to a ninth embodiment of the present invention;

FIG. 25 is a schematic view showing the detail of a mechanical-quantity measuring device according to a tenth embodiment of the present invention;

FIG. 26 is a schematic view showing an attaching state of the mechanical-quantity measuring device of the present invention; and

FIG. 27 is a schematic view showing the optimal shape of a mechanical-quantity measuring device according to an eleventh embodiment of the present invention.

Claims

1. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor forming a wheatstone bridge by diffusion layers, respectively,wherein the diffusion resistors composing the first sensor have mutual distance smaller than their length in the longitudinal direction,wherein the diffusion resistors comprising the second sensor have mutual distance smaller than their length in the longitudinal direction, andwherein the distance between the first sensor and the second sensor is smaller than the length in the longitudinal direction of the diffusion resistor.

2. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor,wherein the first sensor comprises four pieces of p-type diffusion layers directing to a <110> direction in a longitudinal direction, andwherein the second sensor comprises four pieces of n-type diffusion layers directing to a <100> direction in a longitudinal direction.

3. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor formed on the {100} surface of the semiconductor substrate composed of monocrystalline silicon,wherein the first sensor comprising a wheatstone bridge comprising two pieces of p-type diffusion resistors in which a current flows to a <110> direction and mutually provided in parallel and forming a resistor of the opposite side of the wheatstone bridge, and two pieces of p-type diffusion resistors in which a current flows to a <110> direction orthogonal to the direction of the p-type diffusion resistor and mutually provided in parallel and forming a resistor of the opposite side of the wheatstone bridge, andwherein the second sensor comprising a wheatstone bridge comprising two pieces of n-type diffusion resistors in which a current flows to a <100> direction and mutually provided in parallel and forming a resistor of the opposite side of the wheatstone bridge, and two pieces of n-type diffusion resistors in which a current flows to a <100> direction orthogonal to the direction of the n-type diffusion resistor and mutually provided in parallel and forming a resistor of the opposite side of the wheatstone bridge.

4. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor formed on the {100} surface of the semiconductor substrate composed of a monocrystalline silicon,wherein the first sensor comprises a wheatstone bridge formed by connecting a first p-type impurity diffusion resistor in which a current flows in parallel with a [110] direction, a second p-type impurity diffusion resistor in which a current flows in parallel with a [−110] direction, a third p-type impurity diffusion layer in which a current flows in parallel with [110] direction, and a fourth p-type impurity diffusion resistor in which a current flows in parallel with a [−110] direction in this order, andwherein the second sensor comprises a wheatstone bridge formed by connecting a first n-type impurity diffusion resistor in which a current flows in parallel with a [100] direction, a second n-type impurity diffusion resistor in which a current flows in parallel with a [010] direction, a third n-type impurity diffusion resistor in which a current flows in parallel with a [100] direction, and a fourth n-type impurity diffusion resistor in which a current flows in parallel with a [010] direction in this order.

5. The mechanical-quantity measuring device according to claim 3, wherein the distance among four pieces of the p-type impurity diffusion resistors of the first sensor is smaller than the length in the longitudinal direction of the impurity diffusion resistors,wherein the distance among four pieces of the p-type impurity diffusion resistors of the second sensor is smaller than the length in the longitudinal direction of the impurity diffusion resistors, andwherein the distance between the first sensor and the second sensor is smaller than the length in the longitudinal direction of the impurity diffusion resistors.

6. The mechanical-quantity measuring device according to claim 3, wherein the semiconductor substrate is a p-type, and wherein the periphery of the p-type diffusion resistor of the first sensor is provided with the n-type impurity diffusion layer surrounding the p-type diffusion resistor.

7. The mechanical-quantity measuring device according to claim 3, wherein the semiconductor substrate is an n-type, and wherein the periphery of the n-type diffusion resistor of the second sensor is provided with the p-type impurity diffusion layer surrounding the n-type diffusion resistor.

8. A body of rotation provided with the mechanical-quantity measuring device according to claim 3, wherein a direction of rotation axis of the body of rotation is coordinated with a direction <100> or a direction <110> on the semiconductor substrate surface.

9. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and Attached to a measured object to measure a strain comprising a first sensor and a second sensor, wherein the first sensor and the second sensor comprise respectively, two pieces of n-type impurity diffusion resistors in which a current flows in a <100> direction, mutually provided in parallel and forming a resistor of the opposite side of a wheatstone bridge, and two pieces of p-type diffusion resistors in which a current flows in a <100> direction and forming the resistors of the wheatstone bridge.

10. The mechanical-quantity measuring device according to claim 9, wherein the current flow direction of two pieces of the n-type impurity diffusion resistors of the first sensor is orthogonal to the current flow direction of two pieces of the n-type impurity diffusion resistors of the second sensor.

11. The mechanical-quantity measuring device according to claim 10, wherein two pieces of the n-type impurity diffusion resistors of the first sensor are formed approximately line-symmetrical with two pieces of the n-type impurity diffusion resistors of the second sensor.

12. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain comprising a first sensor and a second sensor, wherein the first sensor and the second sensor comprise two pieces of diffusion resistors with high sensitivity for strain provided in parallel, and two pieces of diffusion resistors with low sensitivity for strain, respectively, andwherein the longitudinal direction of two pieces of the diffusion resistors with high sensitivity for strain of the first sensor is orthogonal to the longitudinal direction of two pieces of the diffusion resistors with high sensitivity for strain of the second sensor, and, two pieces of the diffusion resistors with high sensitivity for strain of the first sensor and two pieces of the diffusion resistors with high sensitivity for strain of the second sensor are formed approximately line-symmetrical.

13. The mechanical-quantity measuring device according to claim 11, wherein the line to be axis of approximately line symmetrical passes through a center point of the main surface of the semiconductor substrate.

14. The mechanical-quantity measuring device according to claim 10, wherein the longitudinal direction of two pieces of the p-type impurity diffusion resistors of the first sensor is orthogonal to the longitudinal direction of two pieces of the p-type impurity diffusion resistors of the second sensor, and are formed approximately line-symmetrical.

15. The mechanical-quantity measuring device according to claim 10, wherein two pieces of the p-type impurity diffusion resistors of the first sensor are approximately in parallel with two pieces of the p-type impurity diffusion resistors of the second sensor.

16. The mechanical-quantity measuring device according to claim 9, wherein the n-type impurity diffusion resistor of the first sensor is arranged at a position closer to the centroid of the semiconductor substrate main surface than the p-type impurity diffusion resistor of the first sensor.

17. The mechanical-quantity measuring device according to claim 9, wherein the distance between the n-type impurity diffusion resistor of the first sensor and the n-type impurity diffusion resistor of the second sensor is shorter than the distance between the p-type impurity diffusion resistor of the first sensor and the p-type impurity diffusion resistor of the second sensor.

18. A mechanical-quantity measuring device provided with a strain detection unit on a semiconductor substrate surface and Attached to a measured object to measure a strain comprising a first sensor and a second sensor, wherein the first sensor and the second sensor comprise two pieces of the diffusion resistors with high sensitivity for strain and two pieces of the diffusion resistors with low sensitivity for strain, respectively, andwherein the diffusion resistor with high sensitivity for strain of the first sensor is arranged at a position closer to the centroid of the semiconductor substrate than the diffusion resistor with low sensitivity for strain of the first sensor.

19. A mechanical-quantity measuring device comprising a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain comprising a plurality of p-type impurity diffusion resistors and n-type impurity diffusion resistors forming a wheatstone bridge, wherein the semiconductor substrate is a p-type, andwherein a the n-type impurity diffusion layer which does not form the wheatstone bridge is provided in the periphery of the p-type impurity diffusion resistor.

20. A mechanical-quantity measuring device comprising a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain comprising a plurality of p-type impurity diffusion resistors and n-type impurity diffusion resistors forming a wheatstone bridge, wherein the semiconductor substrate is a n-type, andwherein a the p-type impurity diffusion layer which does not form the wheatstone bridge is provided in the periphery of the n-type impurity diffusion resistor.

21. The mechanical-quantity measuring device according to claim 19, wherein the impurity diffusion resistors have a mutual distance shorter than their length in the longitudinal direction.

22. The mechanical-quantity measuring device according to claim 12, wherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the first sensor are mutually in parallel in the longitudinal direction, and provided side by side in the <110> direction, andwherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the second sensor are directed in the longitudinal direction orthogonal to the longitudinal direction of the impurity diffusion resistors of the first sensor, and are provided side by side in the same direction as the <110> direction.

23. A mechanical-quantity measuring device including a wheatstone bridge formed by a diffusion resistors on a semiconductor substrate surface, the device comprising: a first diffusion resistor, a second diffusion resistor, a third diffusion resistor, and a fourth diffusion resistor configuring the wheatstone bridge and connected in this order; andat least four pieces of wirings mutually connecting the diffusion resistors and lead wires connected to an external circuit outside of the wheatstone bridge,wherein a number of the lead wirings is five or more.

24. A mechanical-quantity measuring device including a wheatstone bridge formed by a diffusion resistors on a semiconductor substrate surface, the device comprising: a first diffusion resistor, a second diffusion resistor, a third diffusion resistor, and a fourth diffusion resistor configuring the wheatstone bridge and connected in this order;four pieces of wirings mutually connecting the diffusion resistors, and lead wires connected to an external circuit outside of the wheatstone bridge;the first diffusion resistor including a first main body resistor connected in series and a first adjusting resistor smaller in resistance value than the first main body resistor; andthe lead wirings being connected to the four pieces of wirings and between the first main body resistor and the first adjusting resistor.

25. The mechanical-quantity measuring device according to claim 24, wherein the first diffusion resistor comprising the first main body resistor, the first adjusting resistor, and a second adjusting resistor connected in this order, andwherein the lead wires are connected between the first adjusting resistor and the second adjusting resistor.

26. The mechanical-quantity measuring device according to claim 24, wherein the third diffusion resistor comprises a third main body resistor and a third adjusting resistor,wherein the lead wires are connected between the third main body resistor and the third adjusting resistor, andwherein the first adjusting resistor and the third adjusting resistor are arranged such that the position for each main body resistor is at a diagonal side on the wheatstone bridge.

27. The mechanical-quantity measuring device according to claim 24, wherein the first diffusion resistor is a diffusion resistor with low sensitivity for strain.

28. The mechanical-quantity measuring device according to claim 24, wherein the first diffusion resistor and third diffusion resistor are a p-type impurity diffusion resistor in which a current flows in a direction parallel with <100>, and the second diffusion resistor and fourth diffusion resistor are a n-type diffusion in which a current flows in a direction parallel with <100>.

29. A mechanical quantity measuring method for measuring a strain by using a mechanical-quantity measuring device including a wheatstone bridge formed by diffusion resistors on a semiconductor substrate surface, the mechanical-quantity measuring device including diffusion resistors forming a wheatstone bridge on a semiconductor substrate, wirings mutually connecting the diffusion resistors, and lead wires of five or more pieces connecting the diffusion resistors to an external circuit, comprising: the steps of measuring a resistance value of the diffusion resistor;the step of deciding four pieces of lead wires used for the measurement of a strain from among the lead wires of five or more pieces; andthe step letting flow current to the decided lead wires and performing a strain measurement.

30. The mechanical-quantity measuring device according to claim 29, wherein the decision of the lead wires is performed at the manufacturing stage of the mechanical-quantity measuring device.

31. The mechanical-quantity measuring device according to claim 29, wherein the measurement of the resistance value of the diffusion resistor is performed in a state in which the mechanical-quantity measuring device is attached to a measured object.

32. A mechanical-quantity measuring device comprising a wheatstone bridge formed by a diffusion resistor on a semiconductor substrate surface, wherein the wheatstone bridge composed of two pieces of diffusion resistors formed by poly silicon and two pieces of diffusion resistors with low sensitivity for strain.

33. A mechanical-quantity measuring device comprising a wheatstone bridge formed by a diffusion resistor on a semiconductor substrate surface comprising: the first sensor composed of the wheatstone bridge formed by two pieces of poly silicon wiring resistors forming a resistor of the opposite side of the wheatstone bridge, and two pieces of p-type diffusion layers in which a current flows in a parallel direction with a <100>.

34. The mechanical-quantity measuring device according to claim 33 comprising the second sensor, wherein the first sensor comprising the wheatstone bridge formed by two pieces of poly silicon wiring resistor forming a resistor of the opposite side of the wheatstone bridge, and two pieces of p-type diffusion layers in which a current flows in a parallel direction with a <100>, andwherein the longitudinal direction of the poly silicon wiring resistor of the first sensor and the longitudinal direction of the poly silicon wiring resistor of the second sensor are orthogonal to each other.

35. The mechanical-quantity measuring device according to claim 33, wherein the p-type diffusion resistor comprises a main body resistor and an adjusting resistor smaller in resistance value than the main body resistor, andwherein the lead wires to be connected to the external device are connected between the p-type diffusion resistor and the poly silicon wiring resistor and between the main body resistor and the adjusting resistor.

36. A mechanical-quantity measuring device including a wheatstone bridge formed by an impurity diffusion resistor on a semiconductor substrate surface, comprising: a first sensor, a second sensor, and a third sensor,wherein the first sensor includes two pieces of n-type diffusion resistors in which a current flows in a <100> direction and mutually provided in parallel and forming a resistor of the opposite side of the wheatstone bridge and two pieces of p-type diffusion layers in which a current flows in a <100> direction and forming resistors of a wheatstone bridge,wherein the second sensor includes two pieces of n-type diffusion in which a current flows in a <100> direction orthogonal to the n-type diffusion layer of the first sensor and mutually provided in parallel and forming resistors of the opposite side of the wheatstone bridge and two pieces of p-type diffusion layers in which a current flows in a <100> direction and forming resistors of a wheatstone bridge, andwherein the third sensor includes four pieces of the p-type diffusion resistors in which a current flows to a <110> direction and forming a resistors of the wheatstone bridge.

37. A mechanical-quantity measuring device including a wheatstone bridge formed by an impurity diffusion resistor on a semiconductor substrate surface comprising: a first sensor, a second sensor, and a third sensor,wherein the first sensor forms the wheatstone bridge by two pieces of diffusion resistors with high sensitivity for strain formed in parallel and two pieces of diffusion resistors with low sensitivity for strain,wherein the second sensor forms the wheatstone bridge by two pieces of diffusion resistors with high sensitivity for strain and orthogonal to the diffusion resistor with high sensitivity for strain of the first sensor in the longitudinal direction and two pieces of diffusion resistors with low sensitivity for strain, andwherein the third sensor forms the wheatstone bridge by four pieces of diffusion resistors with high sensitivity for strain.

38. The mechanical-quantity measuring device according to claim 36, wherein two pieces of the n-type diffusion resistors and two pieces of the p-type diffusion resistors of the first sensor are mutually in parallel in the longitudinal direction and arranged side by side in the <110> direction,wherein two pieces of the n-type diffusion resistors and two pieces of the p-type diffusion resistors of the second sensor have the longitudinal directions thereof directed to the direction orthogonal to the longitudinal direction of the impurity diffusion resistors of the first sensor and arranged side by side in the same direction with the <110> direction, andwherein the impurity diffusion resistors of the third sensor are provided in the area at the <100> direction side of the first sensor and the area of the <100> direction side of the second sensor.

39. The mechanical-quantity measuring device according to claim 1, comprising: a temperature sensor including a PN junction provided on the semiconductor substrate.

40. A mechanical-quantity measuring device including a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor,wherein the second sensor is a sensor detecting the peeling off of the semiconductor substrate.

41. A mechanical-quantity measuring device including a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: diffusion resistors forming a wheatstone bridge on the semiconductor substrate; anda differential amplifier circuit amplifying signals outputted from the wheatstone bridge on the semiconductor substrate.

42. The mechanical-quantity measuring device according to claim 41, wherein the wheatstone bridge is available in plurality, and the number of the differential amplifiers is the same as the number of the wheatstone bridges.

43. The mechanical-quantity measuring device according to claim 41, wherein the resistors connected to the amplifiers excepting the resistance forming the wheatstone bridge is directed to the same direction on the semiconductor substrate in its longitudinal direction.

44. The mechanical-quantity measuring device according to claim 43, wherein the resistors connected to the amplifiers are approximately formed line-symmetrical on the semiconductor substrate.

45. A mechanical-quantity measuring device including a strain detection unit on a semiconductor substrate surface and attached to a measured object to measure a strain, comprising: a first sensor and a second sensor having a wheatstone bridge formed by diffusion resistors, respectively,a first amplifier that amplifies signals outputted by the first sensor, anda second amplifier that amplifies signals outputted by the second sensor,wherein the distance between the impurity diffusion resistors forming the wheatstone bridge of the first sensor and the impurity diffusion resistors forming the wheatstone bridge of the second sensor is shorter than the distance between the transistor of the first amplifier and the transistor of second amplifier.

46. The mechanical-quantity measuring device according to claim 45, wherein the longitudinal direction of a feedback resistor connected to the first amplifier and the longitudinal direction of the resistor of the feedback resistor connected to the second amplifier are directed in the same direction.

47. The mechanical-quantity measuring device according to claim 45, wherein the impurity diffusion resistor of the first sensor and the resistor of the feedback resistor connected to the first amplifier are directed to the same direction in its longitudinal direction, andwherein the impurity diffusion resistor of the second sensor and the resistor of the feedback resistor connected to the second amplifier are directed to the same direction in its longitudinal direction.

48. The mechanical-quantity measuring device according to claim 45, wherein the first sensor and the second sensor are adjacent to each other, andwherein the first amplifier and the second amplifier are adjacent to the first and second sensors so as to be arranged at both sides of the first and second sensors.

49. The mechanical-quantity measuring device according to claim 45, wherein the impurity diffusion resistors of the first sensor and the impurity diffusion resistors of the second sensor are orthogonal in their longitudinal direction, and the centers of the impurity diffusion resistors of the first sensor are brought into line, and the centers of the impurity diffusion resistors of the second sensor are brought into line, andwherein the first amplifier and the second amplifier are arranged at both sides of the first sensor and second sensor.

50. The mechanical-quantity measuring device according to claim 45, wherein the amplifier includes a resistor for low gain and a resistor for high gain, andwherein the resistor for low gain is arranged at a position closer to the impurity diffusion resistor than the resistor for high gain.

51. The mechanical-quantity measuring device according to claim 45, wherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the first sensor are mutually in parallel in their longitudinal direction and arranged side by side in a <110> direction, andwherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the second sensor are directed to the direction orthogonal to the longitudinal direction of the impurity diffusion resistors of the first sensor in their longitudinal direction and provided side by side in the same direction as the <110> direction.

52. The mechanical quantity measure device according to claim 1, wherein the strain detection unit is 49×(chip thickness)0.5 μm or more from a chip end.

53. The mechanical-quantity measuring device according to claim 20, wherein the impurity diffusion resistors have a mutual distance shorter than their length in the longitudinal direction.

54. The mechanical-quantity measuring device according to claim 18, wherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the first sensor are mutually in parallel in the longitudinal direction, and provided side by side in the <110> direction, andwherein two pieces of the n-type impurity diffusion resistors and two pieces of the p-type impurity diffusion resistors of the second sensor are directed in the longitudinal direction orthogonal to the longitudinal direction of the impurity diffusion resistors of the first sensor, and are provided side by side in the same direction as the <110> direction.