An optimized magnetoresistive sensor and magnetoresistive sensing structure

Abstract

The application relates to the technical field of sensors, in particular to a magnetoresistance sensor and a single chip, which comprises a base body, at least one inclined groove is arranged on the plane of the base body, the inclined groove comprises two inclined surfaces, a plurality of magnetoresistance sensing units are arranged on each inclined surface in series, a plurality of conductor units are arranged on each magnetoresistance sensing unit to form at least one bridge arm; the plurality of conductor units and the plurality of magnetoresistance sensing units extend to the plane of the base body and the bottom plane of the inclined surface. The application has the beneficial effects that the vertical magnetic component and / or the horizontal magnetic component can be sensed, the problem of low sensitivity caused by the etching deviation of the inclined surface when the inclined surface angle is too large can be reduced, the process error can be compensated, the measurement accuracy of the magnetic field can be improved, and the overall yield of the product can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, in particular to an optimized magnetoresistance sensor and magnetoresistance sensing structure. BACKGROUND

[0002] The magnetoresistance principle refers to that the strength and direction of the magnetic field in the space environment can cause the self-resistance value of the magnetic induction structure to change, and then the strength and direction of the magnetic field in the space environment can be measured according to the change amount of the resistance value. The magnetic induction structure usually distributed in a plane can only measure the magnetic field component in the plane, and has no response to the magnetic field component perpendicular to the plane.

[0003] In the prior art, a commonly used method is to vertically place the planar magnetoresistance chip and the package body to detect the magnetic field component in the vertical direction, as shown in FIG. 1, however, this technical solution has angle error in the packaging process, the process wire bonding is relatively complex, and the cost is high; another method is to set a vertical groove or an inclined groove on the surface of the chip, and the chip can be integrated into a single chip structure with a special integrated circuit, or the chip can be packaged and wired into a double-chip structure, the core technology of this technical solution is to set a vertical groove or an inclined groove on the surface of the chip, and distribute magnetoresistance materials to detect the vertical component of the magnetic field, wherein the vertical groove is set on the surface of the chip, as shown in FIG. 2, the defect is that the deposition rate of the magnetic material on the surface is greater than the deposition rate on the side wall, so that the thickness of the side wall magnetoresistance is less than the thickness of the surface magnetoresistance, and it is difficult to continue to increase the thickness of the magnetoresistance on the side wall due to the preparation process, thereby causing low sensitivity of the vertical direction magnetoresistance and large noise; or the inclined groove is set on the surface of the chip, as shown in FIG. 3, the defect is that if the angle of the inclined groove is small, the sensitivity of the detected vertical direction magnetoresistance component is low, and if the angle of the inclined groove is large, the process difficulty is increased. Therefore, the above problems become a difficult problem to be solved by the person skilled in the art. Figure 1 Figure 2 Figure 3 SUMMARY

[0004] In view of the above problems in the prior art, the present application provides an optimized magnetoresistance sensor and magnetoresistance sensing structure.

[0005] The specific technical solution is as follows:

[0006] The present application provides an optimized magnetoresistance sensor, which comprises:

[0007] A base body, at least one inclined groove is arranged on the plane of the base body, the inclined groove comprises two inclined surfaces, a plurality of magnetoresistance sensing units are arranged on each inclined surface in series, a plurality of conductor units are arranged on each magnetoresistance sensing unit to form at least one bridge arm; ​​​

[0008] The plurality of conductor units and the plurality of magnetic resistance sensing units extend to the plane of the base and the bottom plane of the inclined surface.

[0009] Preferably, the angle between each inclined surface and the bottom plane ranges from 15° to 85°.

[0010] Preferably, the angle between each inclined surface and the plane of the base ranges from 15° to 85°.

[0011] Preferably, the angle between the magnetic resistance sensing unit and the conductor unit ranges from 15° to 45°.

[0012] Preferably, by changing the orientation angle of the conductor unit, the initial magnetization direction and / or the current direction of the magnetic resistance sensing unit, and the position of the conductor unit and the magnetic resistance sensing unit on the inclined surface, a magnetic resistance sensor that only senses the vertical magnetic field component or only senses the horizontal magnetic field component is obtained.

[0013] Preferably, the bridge arm connection is a Wheatstone bridge.

[0014] The application also provides an optimized magnetic resistance sensing structure, wherein a plurality of magnetic resistance sensors as described above are included, and the magnetic resistance sensing structure comprises:

[0015] a plurality of first direction sensors distributed in the plane of the base and / or in the inclined surface to detect the magnetic field component in the first direction; and / or

[0016] a plurality of second direction sensors distributed in the plane of the base and / or in the inclined surface to detect the magnetic field component in the second direction; and / or

[0017] a plurality of third direction sensors distributed in the inclined surface to detect the magnetic field component in the third direction.

[0018] Preferably, the first direction sensor is an X-axis sensor, the second direction sensor is a Y-axis sensor, and the third direction sensor is a Z-axis sensor.

[0019] Preferably, a single chip is formed with a dedicated integrated circuit process and a CMOS circuit; or

[0020] A multi-chip is formed with a packaging integration process and a CMOS chip.

[0021] The technical scheme has the following advantages or beneficial effects: by arranging multiple series of magnetic resistance sensing units and multiple conductor units on the inclined surface of the inclined groove, and by extending the multiple series of magnetic resistance sensing units and the multiple conductor units to the plane of the base body and the bottom plane of the inclined surface, a magnetic resistance sensor is formed to sense the vertical magnetic component and / or the horizontal magnetic component, which can reduce the problem of low sensitivity caused by the etching deviation of the inclined surface when the inclined surface angle is too large, and improve the measurement accuracy of the magnetic field, and improve the stability of the process and the overall yield of the product. BRIEF DESCRIPTION OF DRAWINGS

[0022] Embodiments of the present application are described more fully below with reference to the accompanying drawings. However, the accompanying drawings are only used for illustration and explanation, and do not constitute a limitation on the scope of the present application.

[0023] Figure 1 A structure diagram for detecting the vertical magnetic resistance component of a chip according to the prior art of the present application;

[0024] Figure 2 Another structure diagram for detecting the vertical magnetic resistance component of a chip by arranging a vertical groove according to the prior art of the present application;

[0025] Figure 3 Another structure diagram for detecting the vertical magnetic resistance component of a chip by arranging an inclined groove according to the prior art of the present application;

[0026] Figure 4 A structure diagram of a magnetic resistance sensor according to an embodiment of the present application;

[0027] Figure 5 A diagram of the magnetic sensing units and conductor units distributed on both sides of the inclined groove according to an embodiment of the present application;

[0028] Figure 6 A simulation diagram of the magnetization of the magnetic resistance sensing units on the inclined surface under the external detection magnetic field according to an embodiment of the present application;

[0029] Figure 7 A diagram of the first direction sensor and the third direction sensor of the magnetic resistance sensing structure according to an embodiment of the present application;

[0030] Figure 8 A diagram of the second direction sensor and the third direction sensor of the magnetic resistance sensing structure according to an embodiment of the present application;

[0031] Figure 9 A diagram of the first direction sensor of the magnetic resistance sensing structure according to an embodiment of the present application;

[0032] Figure 10 A diagram of the second direction sensor of the magnetic resistance sensing structure according to an embodiment of the present application;

[0033] Figure 11 A structural diagram of a magnetic resistance sensing structure of an embodiment of the present application;

[0034] Figure 12 Another structural diagram of a magnetic resistance sensing structure of an embodiment of the present application.

[0035] The above-mentioned reference signs mark the description:

[0036] Base 1; inclined groove 2; inclined surface 20; bottom plane 200; magnetic resistance sensing unit 3; conductor unit 4. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0038] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0039] The present application will be further described below in combination with the drawings and specific embodiments, but is not limited to the present application.

[0040] The present application provides a magnetic resistance sensor, wherein, in combination with Figures 4-6 as shown, comprising:

[0041] A base 1, at least one inclined groove 2 is arranged on the plane of the base 1, the inclined groove 2 includes two inclined surfaces 20, each inclined surface 20 is provided with a plurality of series-connected magnetic resistance sensing units 3, each magnetic resistance sensing unit 3 is provided with a plurality of conductor units 4, forming at least one bridge arm;

[0042] The plurality of conductor units 4 and the plurality of magnetic resistance sensing units 3 extend to the plane 10 of the base 1 and the bottom plane 200 of the inclined surface 20.

[0043] In the embodiment, the inclined groove 2 is arranged on the plane of the substrate 1, the magnetoresistance sensing units 3 and the conductor units 4 are distributed on the inclined surface 20 of the inclined groove 2 and the plane of the substrate 1 and the bottom plane 200 of the inclined surface 20 connected with both ends of the inclined surface 20, so that the magnetoresistance sensing units 3 and the conductor units 4 on the inclined surface 20 can convert the magnetic field in the vertical direction into the plane of the substrate 1 and the bottom plane 200, the magnetoresistance sensing units 3 and the conductor units 4 in the plane of the substrate 1 and the bottom plane 200 can measure the converted signal, the sensitivity of detecting the magnetic component in the vertical direction is increased, the magnetic component in the vertical direction and / or the magnetic component in the horizontal direction can be sensed, the problem of low sensitivity caused by the etching deviation of the inclined surface when the angle of the inclined surface is too large can be reduced, the process error can be compensated, the measurement accuracy of the magnetic field is improved, and the overall yield of the product is improved.

[0044] In addition, it should be noted that, through simulation analysis, the sensitivity of the structure that the magnetoresistance sensing units 3 and the conductor units 4 are distributed on the inclined surface 20 of the inclined groove 2 and the plane of the substrate 1 and the bottom plane 200 of the inclined surface 20 connected with both ends of the inclined surface 20 is increased by nearly 30% compared with the structure that the magnetoresistance sensing units 3 and the conductor units 4 are only distributed on the inclined surface.

[0045] In a preferred embodiment, the included angle between each inclined surface and the bottom plane ranges from 15° to 85°.

[0046] Specifically, in the embodiment, the included angle between each inclined surface 20 and the bottom plane 200 can range from 15° to 85°.

[0047] In a preferred embodiment, the included angle between each inclined surface 20 and the plane of the substrate 1 ranges from 15° to 85°.

[0048] Specifically, in the embodiment, the included angle between each inclined surface 20 and the plane of the substrate 1 can range from 15° to 85°.

[0049] In a preferred embodiment, the included angle between the magnetoresistance sensing unit 3 and the conductor unit 4 ranges from 15° to 45°.

[0050] Specifically, in the embodiment, the included angle between the magnetoresistance sensing unit 3 and the conductor unit 4 is about 45°, so that the included angle between the current direction on the magnetoresistance sensing unit 3 and the initial magnetization direction thereof is 45° or 135°, thereby obtaining the best linear measurement range and improving the measurement accuracy of the magnetic field.

[0051] In a preferred embodiment, by changing the orientation angle of the conductor unit 4, the initial magnetization direction and / or the current direction of the magnetoresistance sensing unit 3, and / or the position of the conductor unit 4 and the magnetoresistance sensing unit 3 on the slope 20, only the vertical magnetic field component of the base body is sensed; or

[0052] only the horizontal magnetic field component of the base body or the bottom plane of the slope is sensed.

[0053] Specifically, the at least one bridge arm formed by the plurality of series-connected magnetoresistance sensing units 3 and the plurality of conductor units 4 in the above technical solution is arranged on both sides of the slope 20 with a set 15°-85° inclination angle, and the plane of the base body 1 and the bottom plane 200 of the slope 20 connected with both ends of the slope 20, while changing the orientation angle of the conductor unit 4, the initial magnetization direction and / or the current direction of the magnetoresistance sensing unit 3, and / or the position of the conductor unit 4 and the magnetoresistance sensing unit 3 on the slope 20, so that the bridge arm formed by the plurality of series-connected magnetoresistance sensing units 3 and the plurality of conductor units 4 only measures the vertical magnetic field component of the base body 1 and / or only measures the horizontal magnetic field component in the plane of the base body 1, as shown in Figure 7 、 Figure 8 .

[0054] In a preferred embodiment, the bridge arm is connected in a Wheatstone bridge.

[0055] Specifically, the at least one bridge arm formed by the plurality of series-connected magnetoresistance sensing units 3 and the plurality of conductor units 4 in the above technical solution can be connected in a Wheatstone bridge.

[0056] The application also provides an optimized magnetoresistance sensing structure, wherein a plurality of magnetoresistance sensors as described above are included, and the magnetoresistance sensing structure comprises:

[0057] a plurality of first direction sensors distributed in the plane of the base body 1 and / or in the slope 20 to detect the magnetic field component in the first direction; and / or

[0058] a plurality of second direction sensors distributed in the plane of the base body 1 and / or in the slope 20 to detect the magnetic field component in the second direction; and / or

[0059] a plurality of third direction sensors distributed in the slope 20 to detect the magnetic field component in the third direction.

[0060] Specifically, in the embodiment, the bridge arm formed by the plurality of series-connected magnetoresistance sensing units 3 and the plurality of conductor units 4 in the horizontal direction arranged in the plane of the base body 1 and / or the bottom plane 200 only measures the horizontal magnetic field component in the plane of the base body 1, as shown in the first direction sensor and the second direction sensor in Figure 9 、 Figure 10 .

[0061] In this embodiment, combined with Figures 7-10 As shown, a single / multi-axis magnetoresistive sensing structure can be formed by placing a first direction sensor, a second direction sensor, and a third direction sensor, which are formed by using multiple series-connected magnetoresistive sensing units 3 and multiple conductor units 4, on the same substrate 1. Figure 11 As shown, the first and second direction sensors are respectively distributed in the plane of the substrate 1 to sense the horizontal magnetic field component. The third direction sensor is distributed on the inclined groove 2 and extends into the plane of the substrate 1 and / or the bottom plane 200 of the inclined surface 20. At least one set of third direction sensors can be used to sense the vertical magnetic field component; as shown Figure 12 As shown, the first direction sensor, the second direction sensor, and the third direction sensor are all distributed on the inclined groove 2 and extend into the plane of the substrate 1 or into the bottom plane 200 of the inclined surface 20 to sense the magnetic field components in the horizontal and vertical directions.

[0062] In a preferred example, Figure 11 and Figure 12 The magnetoresistive sensing structure shown can be integrated with an application-specific integrated circuit (ASIC) process and a CMOS circuit to form a single chip, or integrated with a CMOS chip through a packaging process to form a multi-chip. Furthermore, in the above technical solution, the first direction sensor is an X-axis sensor, the second direction sensor is a Y-axis sensor, and the third direction sensor is a Z-axis sensor.

[0063] The above technical solution has the following advantages or beneficial effects: by setting multiple series-connected magnetoresistive sensing units and multiple conductor units on the inclined surface of the inclined trench, and by having multiple series-connected magnetoresistive sensing units and multiple conductor units extend to the plane of the substrate and the bottom plane of the inclined surface, a single-axis or multi-axis magnetoresistive sensor is formed to sense the magnetic components in the vertical direction and / or the magnetic components in the horizontal direction. This can reduce the problem of low sensitivity caused by the etching deviation of the inclined surface when the inclined surface angle is too large, compensate for process errors and improve the measurement accuracy of the magnetic field, and improve the overall yield of the product.

[0064] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. An optimized magnetoresistive sensor, characterized in that, include: A substrate, wherein at least one inclined groove is provided on the plane of the substrate, the inclined groove includes two inclined surfaces, each of the inclined surfaces is provided with a plurality of magnetoresistive sensing units connected in series, and each of the magnetoresistive sensing units is provided with a plurality of conductor units to form at least one bridge arm; The plurality of conductor units and the plurality of magnetoresistive sensing units extend to the plane of the substrate and the bottom plane of the slope.

2. The magnetoresistive sensor as described in claim 1, characterized in that, The angle between each of the inclined planes and the bottom plane ranges from 15° to 85°.

3. The magnetoresistive sensor as described in claim 1, characterized in that, The angle between each of the inclined planes and the plane of the substrate ranges from 15° to 85°.

4. The magnetoresistive sensor as described in claim 1, characterized in that, The angle between the magnetoresistive sensing unit and the conductor unit ranges from 15° to 45°.

5. The magnetoresistive sensor as described in claim 1, characterized in that, By changing the orientation angle of the conductor unit, the initial magnetization direction and / or current direction of the magnetoresistive sensing unit, and the positions of the conductor unit and the magnetoresistive sensing unit on the inclined plane, only the vertical magnetic field component of the substrate can be sensed; or Only the horizontal magnetic field component of the bottom plane of the substrate or the inclined surface is sensed.

6. The magnetoresistive sensor as described in claim 1, characterized in that, The bridge arms are connected in the form of a Wheatstone bridge.

7. An optimized magnetoresistive sensing structure, characterized in that, The magnetoresistive sensing structure comprises a plurality of magnetoresistive sensors as described in any one of claims 1-6, wherein the magnetoresistive sensing structure includes: Multiple first-direction sensors are distributed within a plane and / or an inclined plane of a substrate to detect the magnetic field component in the first direction; and / or Multiple second-direction sensors are distributed within the plane and / or inclined surface of the substrate to detect the magnetic field component in the second direction; and / or Multiple third-direction sensors are distributed within the inclined plane to detect the third-direction upward magnetic field component.

8. The magnetoresistive sensing structure as described in claim 7, characterized in that, The first orientation sensor is an X-axis sensor, the second orientation sensor is a Y-axis sensor, and the third orientation sensor is a Z-axis sensor.

9. The magnetoresistive sensing structure as described in claim 7, characterized in that, It is integrated with an application-specific integrated circuit (ASIC) process and CMOS circuitry to form a single chip; or A multi-chip system is formed by integrating the CMOS chip with the packaging and integration process.

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