A three-dimensional magnetic field detection chip, sensor and magnetic field component detection method

Abstract

The present application discloses a three-dimensional magnetic field detection chip, a sensor and a magnetic field component detection method. The three-dimensional magnetic field detection chip includes a Hall wafer array obtained by cutting the same wafer as a whole and a magnet covering the Hall wafer array. The Hall wafer array includes four magnetic sensing parts and electrode parts arranged in a rectangular array. The working current directions of the two diagonally arranged magnetic sensing parts are orthogonal. The first diagonal between the two magnetic sensing parts arranged at the first diagonal is orthogonal to the second diagonal between the two magnetic sensing parts arranged at the second diagonal. The orthographic projection of the magnet on the Hall wafer array covers the sensitive central area of ​​each magnetic sensing part. The boundary of the orthographic projection of the magnet on the two magnetic sensing parts arranged at the first diagonal is perpendicular to the first diagonal, and the boundary of the orthographic projection of the magnet on the two magnetic sensing parts arranged at the second diagonal is perpendicular to the second diagonal. The three-dimensional magnetic field detection chip has the capabilities of zero offset, low cost, low error, miniaturization and anti-interference.

Description

Technical Field

[0001] The present application relates to the field of magnetic sensing technology, and in particular to a three-dimensional magnetic field detection chip and sensor and a magnetic field component detection method. Background Art

[0002] Hall chips are widely used in motor drive, current sensing and other fields. With the development of technology, there is an increasing demand for multi-dimensional Hall chips that can simultaneously sense multi-axis magnetic fields. The main solution of existing 3D Hall technology is to discretely integrate multiple sensor chips with orthogonal sensitive axes to achieve three-dimensional signal acquisition. It has problems such as low integration, large size, and high process difficulty.

[0003] There is also a planar 3D technology that uses a magnet to twist the parallel magnetic field to the Hall sensitive direction. Although it can realize 3D detection of magnetic fields, its signal is sensitive to changes in edge position, which brings the problem of too high requirements for installation errors. In addition, its Hall phase distance is large, resulting in such solutions having difficult-to-overcome shortcomings such as large size, high cost, and sensitivity to installation errors. In particular, various Hall 3D sensors currently have signal zero offset, resulting in large signal deviation, requiring multiple regular calibrations or reducing actual measurement accuracy. Summary of the invention

[0004] In order to overcome the above shortcomings, the purpose of this application is to provide a three-dimensional magnetic field detection chip, a sensor and a magnetic field component detection method, wherein the three-dimensional magnetic field detection chip has zero offset, low cost, low error, miniaturization and anti-interference.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a three-dimensional magnetic field detection chip, the three-dimensional magnetic field detection chip comprising:

[0007] A Hall wafer array, wherein the Hall wafer array is a continuous whole obtained by cutting the same wafer as a whole, and comprises at least four magnetic sensing parts and electrode parts electrically connected to the four magnetic sensing parts, wherein the four magnetic sensing parts are arranged in a rectangular array, the working current directions of the two diagonally arranged magnetic sensing parts are orthogonal, and the first diagonal line between the two magnetic sensing parts arranged at a first diagonal and the second diagonal line between the two magnetic sensing parts arranged at a second diagonal are orthogonal to each other;

[0008] A focusing magnet is covered on the Hall wafer array, and its orthographic projection on the Hall wafer array covers the sensitive central area of ​​each magnetic sensing part. The boundary of the orthographic projection of the focusing magnet on the two magnetic sensing parts arranged at the first diagonal is perpendicular to the first diagonal line, and the boundary of the orthographic projection of the focusing magnet on the two magnetic sensing parts arranged at the second diagonal is perpendicular to the second diagonal line.

[0009] In one embodiment, the positive projection of the magnetic focusing body on the Hall wafer array is a regular N-gon, where N is an even number greater than or equal to 4;

[0010] The length of each side of the magnetic focusing body equally divides the induction area of ​​the magnetic induction part covered by the magnetic focusing body.

[0011] In one embodiment, the thickness of the magnetizing body in the z-axis direction is between 20 and 1000 microns.

[0012] In one embodiment, the electrode comprises:

[0013] At least four signal electrodes are respectively arranged at the end of each magnetic sensing portion;

[0014] A working positive electrode connected to the four magnetic induction parts;

[0015] and a ground electrode, wherein the ground electrode includes a common ground electrode, or the ground electrode includes at least three working ground electrodes and one signal common ground electrode.

[0016] In one embodiment, the common ground electrode or the signal common ground electrode is arranged at the center position of the four magnetic sensing parts;

[0017] The common ground electrode or the signal common ground electrode comprises a buffer layer extending along the z-axis direction and an electrode layer arranged on the buffer layer;

[0018] The magnetic concentrator is provided with a through hole through which the common ground electrode or the signal common ground electrode can pass.

[0019] In one embodiment, the projection of the through hole on the Hall wafer array is circular or elliptical.

[0020] In one embodiment, the common ground electrode or the signal common ground electrode extends to the periphery of the four magnetic sensing parts;

[0021] An insulating layer is arranged between the magnetic focusing body and the Hall wafer array.

[0022] A second aspect of the present application provides a three-dimensional magnetic field sensor, the three-dimensional magnetic field sensor comprising a package;

[0023] The three-dimensional magnetic field detection chip as mentioned above is disposed in the package body;

[0024] A conditioning circuit, disposed in the package body and electrically connected to the three-dimensional magnetic field detection chip;

[0025] A plurality of pins are symmetrically arranged on two opposite sides of the outside of the package body.

[0026] In a specific embodiment, a plurality of spaced-apart metal wires are further disposed in the package, and the metal wires connect the electrode portion and the conditioning circuit.

[0027] A second aspect of the present application provides a method for detecting magnetic field components based on a three-dimensional magnetic field sensor, the method comprising:

[0028] Acquire signal voltages output by four magnetic induction units and sensitivity gain coefficients of the four magnetic induction units;

[0029] Adjust the signal gain of the magnetic sensing unit based on the conditioning circuit to obtain equal sensitivity gain coefficients of the two magnetic sensing units arranged at a first diagonal angle on the X-axis and equal sensitivity gain coefficients of the two magnetic sensing units arranged at a second diagonal angle on the Y-axis;

[0030] According to the signal voltages output by the four magnetic induction units, the sensitivity gain coefficients of the four magnetic induction units, the X-axis sensitivity gain coefficient and the Y-axis sensitivity gain coefficient, the Z-axis magnetic field component, the X-axis magnetic field component and the Y-axis magnetic field component are obtained. Beneficial Effects

[0031] The three-dimensional magnetic field detection chip in the present application has the effects of zero offset, low cost, low error, miniaturization and anti-interference. The Hall wafer array is a continuous whole obtained by cutting the same wafer as a whole. No complicated packaging process is required, which further reduces the installation error. At the same time, the working current directions of the two diagonally arranged magnetic induction parts in the present application are orthogonal, which can achieve the purpose of eliminating zero offset. The boundary of the positive projection of the magnet on the two magnetic induction parts arranged at the first diagonal is perpendicular to the first diagonal, and the boundary of the positive projection of the magnet on the two magnetic induction parts arranged at the second diagonal is perpendicular to the second diagonal. This design makes the magnet be inclined at 45° between the four magnetic induction parts, and by making the first diagonal between the two magnetic induction parts arranged at the first diagonal and the second diagonal between the two magnetic induction parts arranged at the second diagonal be orthogonal to each other, the X-axis magnetic field is introduced into the two magnetic induction parts arranged at the first diagonal in two opposite directions, and the Y-axis magnetic field is introduced into the two magnetic induction parts arranged at the second diagonal in two opposite directions, so that the magnetic field detection chip can detect the magnetic fields in the x and y directions respectively, and then realize the detection of the magnetic fields in the three-axis directions of X, Y and Z respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure. The shapes and sizes of the components in the accompanying drawings do not reflect the actual proportions and are only intended to illustrate the content of the present application.

[0033] Figure 1Schematic diagram of the structure of the three-dimensional magnetic field detection chip provided in the first aspect of the present application Figure 1 ;

[0034] Figure 2 for Figure 1 Schematic diagram of the wafer array structure;.

[0035] Figure 3 Schematic diagram of the structure of the three-dimensional magnetic field detection chip provided in the first aspect of the present application Figure 2 ;

[0036] Figure 4 Schematic diagram of the structure of the three-dimensional magnetic field detection chip provided in the first aspect of the present application Figure 3 ;

[0037] Figure 5 Schematic diagram of the structure of the three-dimensional magnetic field detection chip provided in the first aspect of the present application Figure 4 ;

[0038] Figure 6 A side view schematic diagram of the three-dimensional magnetic field detection chip provided in the first aspect of the present application;

[0039] Figure 7 A schematic diagram of the magnetic field lines of the three-dimensional magnetic field detection chip provided in the first aspect of the present application;

[0040] Figure 8 A schematic diagram of the structure of a three-dimensional magnetic field sensor provided in the second aspect of the present application Figure 1 ;

[0041] Fig. 9 A schematic diagram of the structure of a three-dimensional magnetic field sensor provided in the second aspect of the present application Figure 2 . DETAILED DESCRIPTION

[0042] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the present application and are not limited to the scope of the present application. The implementation conditions adopted in the examples can be further adjusted as the conditions of the specific manufacturer, and the unspecified implementation conditions are usually the conditions in conventional experiments.

[0043] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connecting" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In this article, "electrical connection" includes the situation where the constituent elements are connected together through an element with some electrical function. "Elements with some electrical function" are not particularly limited as long as they can transfer electrical signals between the connected constituent elements. "Elements with some electrical function" can be, for example, electrodes or wiring, or switching elements such as transistors, or other functional elements such as resistors, inductors or capacitors. "Up", "down", "left", "right", etc. are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0044] In this application, the directions or positional relationships indicated by the terms "upper", "lower", "inner", "middle", etc. are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction.

[0045] The present application discloses a three-dimensional magnetic field detection chip, a sensor, and a magnetic field component detection method. The three-dimensional magnetic field detection chip includes a Hall wafer array and a magnetizer. The Hall wafer array is a continuous whole obtained by cutting the same wafer as a whole. The Hall wafer array includes at least four magnetic sensing parts and an electrode part electrically connected to the four magnetic sensing parts. The four magnetic sensing parts are arranged in a rectangular array. The working current directions of the two diagonally arranged magnetic sensing parts are orthogonal. The first diagonal between the two magnetic sensing parts arranged at the first diagonal and the second diagonal between the two magnetic sensing parts arranged at the second diagonal are mutually orthogonal. The magnetizer covers the Hall wafer array, and the positive projection of the magnetizer on the Hall wafer array covers the sensitive central area of ​​each magnetic sensing part. The boundary of the positive projection of the magnetizer on the two magnetic sensing parts arranged at the first diagonal is perpendicular to the first diagonal, and the boundary of the positive projection of the magnetizer on the two magnetic sensing parts arranged at the second diagonal is perpendicular to the second diagonal. The three-dimensional magnetic field detection chip in the present application has the technical effects of zero offset, low cost, low error, miniaturization and anti-interference.

[0046] Next, combine Figure 1-Figure 7A three-dimensional magnetic field detection chip 100 provided in the first aspect of the present application is described. The three-dimensional magnetic field detection chip 100 has the advantages of zero offset, low cost, low error, miniaturization and anti-interference.

[0047] The three-dimensional magnetic field detection chip 100 includes: a Hall wafer array 110 and a magnetic concentrator 30. The Hall wafer array 110 is a continuous whole obtained by cutting the same wafer as a whole, including at least four magnetic sensing parts 10 and an electrode part 20 electrically connected to the four magnetic sensing parts 10. The combination of the four magnetic sensing parts 10 is arranged in a rectangular array, and the working current directions of the two diagonally arranged magnetic sensing parts 10 are orthogonal. The first diagonal line m between the two magnetic sensing parts 10 arranged at the first diagonal is perpendicular to the second diagonal line n between the two magnetic sensing parts 10 arranged at the second diagonal.

[0048] The focusing magnet 30 is covered on the Hall wafer array 110, and the orthographic projection of the focusing magnet 30 on the Hall wafer array 110 covers the sensitive central area 15 of each magnetic sensing part 10. The boundary of the orthographic projection of the focusing magnet 30 on the two magnetic sensing parts 10 arranged at the first diagonal is perpendicular to the first diagonal m, and the boundary of the orthographic projection of the focusing magnet 30 on the two magnetic sensing parts 10 arranged at the second diagonal is perpendicular to the second diagonal n.

[0049] It should be noted that in this embodiment, the Hall wafer array is a continuous whole obtained by cutting the same wafer as a whole. Specifically, a functional layer is first epitaxially grown on the wafer, and the wafer is made of semiconductor material. The functional layer includes at least four magnetic sensing parts. Then, the wafer is patterned by the method of wafer lithography, and then the electrode parts are made around at least four magnetic sensing parts by the photolithography process, so as to form a Hall wafer array on the patterned wafer. Finally, the Hall wafer array is cut out from the patterned wafer. The Hall wafer arrays cut out by this method are tightly connected to achieve the purpose of zero offset.

[0050] The three-dimensional magnetic field detection chip of the present application has the characteristics of zero offset, low cost, low error, miniaturization and anti-interference. The Hall wafer array 110 is a continuous whole obtained by cutting the same wafer as a whole, and does not require a complicated packaging process, which further reduces the installation error. At the same time, the working current directions of the two diagonally arranged magnetic sensing parts 10 in the present application are orthogonal, which can achieve the purpose of eliminating zero position offset.

[0051] The boundary of the positive projection of the focusing magnet 30 on the two magnetic induction parts 10 arranged at the first diagonal is perpendicular to the first diagonal line m, and the boundary of the positive projection of the focusing magnet 30 on the two magnetic induction parts 10 arranged at the second diagonal is perpendicular to the second diagonal line n. This design makes the focusing magnet 30 and the four magnetic induction parts 10 inclined at 45 degrees, and by making the first diagonal line m between the two magnetic induction parts 10 arranged at the first diagonal and the second diagonal line n between the two magnetic induction parts 10 arranged at the second diagonal be orthogonal to each other, the X-axis magnetic field is respectively introduced into the two magnetic induction parts 10 arranged at the first diagonal in two opposite directions, and the Y-axis magnetic field is respectively introduced into the two magnetic induction parts 10 arranged at the second diagonal in two opposite directions (the specific direction of the magnetic lines of force of the X-axis or the direction of the magnetic lines of force of the Y-axis is as follows: Figure 7 As shown), the magnetic field detection chip can detect the magnetic field in the x and y directions respectively, and then detect the magnetic field in the X, Y, and Z directions respectively.

[0052] refer to Figure 1-Figure 2 In a specific embodiment, the four magnetic induction parts 10 specifically include a first magnetic induction part 10a, a second magnetic induction part 10b, a third magnetic induction part 10c and a fourth magnetic induction part 10d, wherein the first magnetic induction part 10a and the second magnetic induction part 10b are arranged opposite to each other, that is, the first magnetic induction part 10a and the second magnetic induction part 10b are two magnetic induction parts arranged at a first diagonal, the third magnetic induction part 10c and the fourth magnetic induction part 10d are arranged opposite to each other, that is, the third magnetic induction part 10c and the fourth magnetic induction part 10d are two magnetic induction parts arranged at a second diagonal, the connecting line between the first magnetic induction part 10a and the second magnetic induction part 10b is a first diagonal m, the connecting line between the third magnetic induction part 10c and the fourth magnetic induction part 10d is a second diagonal n, the extension direction of the first diagonal m can be the X-axis direction, the extension direction of the second diagonal n can be the Y-axis direction, and the extension direction of the first diagonal m is different from and orthogonal to the extension direction of the second diagonal n, The boundary of the orthographic projection of the focusing magnet 30 on the first magnetic induction part 10a and the boundary of the orthographic projection of the focusing magnet 30 on the second magnetic induction part 10b are both perpendicular to the first diagonal m, the boundary of the orthographic projection of the focusing magnet 30 on the third magnetic induction part 10c and the boundary of the orthographic projection of the focusing magnet 30 on the fourth magnetic induction part 10d are both perpendicular to the second diagonal n, where the boundary of the orthographic projection specifically refers to the boundary line of the focusing magnet.

[0053] refer to Figure 1-Figure 6 In one embodiment, the electrode unit 20 includes at least four signal electrodes 21, a working positive electrode 22 and a ground electrode 23. The four signal electrodes 21 are respectively arranged at the end of each magnetic sensing unit 10; the working positive electrode 22 is connected to the four magnetic sensing units 10; in one embodiment, the three-dimensional magnetic field detection chip 100 has a six-electrode chip structure (such as Figure 1 and Figure 3 As shown in FIG. 1 ), the ground electrode 23 includes a common ground electrode 233a, which refers to an electrode shared by the working ground and the signal ground. The common ground electrode 233a can be set at the center of the four magnetic sensing parts 10, and the common ground electrode 233b can also extend to the periphery of the four magnetic sensing parts 10. In another embodiment, the three-dimensional magnetic field detection chip 100 has a nine-electrode chip structure (such as Figure 4 and Figure 5 As shown), that is, the ground electrode 23 includes at least three working ground electrodes 231 and one signal common ground electrode 232, wherein two adjacent magnetic sensing parts 10 share one working ground electrode 231, and the other two magnetic sensing parts 10 are respectively electrically connected to one working ground electrode 231, and the signal common ground electrode 232 can be set at the center position of the four magnetic sensing parts 10, or can be extended to the periphery of the four magnetic sensing parts 10, such as the first magnetic sensing part 10a and the fourth magnetic sensing part 10d share one working ground electrode 231a, and the third magnetic sensing part 10c is configured with one working ground electrode 23 1c, the second magnetic sensing part 10b is equipped with a working ground electrode 231b. Further, the common ground electrode 233a or the signal common ground electrode 232 located at the center of the four magnetic sensing parts 10 includes a buffer layer 2321 extending axially along the Z axis and an electrode layer 2322 arranged on the buffer layer 2321. Specifically, the thickness of the buffer layer 2321 is determined according to the thickness of the focusing magnet, that is, the function of the buffer layer 2321 is to raise the electrode layer 2322 thereon to the upper surface of the focusing magnet 30, so as to facilitate subsequent wiring and connect with the conditioning circuit 200 (see Figure 8 )connect.

[0054] Continue to refer Figure 1-Figure 6In this embodiment, the focusing magnet 30 can be selected from iron-nickel alloy, nanocrystal or other materials with high magnetic permeability. For the production of the focusing magnet 30, one method is to use a photolithography sputtering process to directly produce the focusing magnet 30 on the Hall wafer array 110. Since this method is to directly produce the focusing magnet 30 on the Hall wafer array 110, there is no installation error, so the above-mentioned signal common ground electrode 232 or common ground electrode 233a can be set at the center position of the four magnetic sensing parts 10, and the signal common ground electrode 232 or common ground electrode 233b can also extend to the periphery of the four magnetic sensing parts 10. If the signal common ground electrode 232 or common ground electrode 233a is set at the center position of the four magnetic sensing parts 10, and it is necessary to reserve a through hole (not marked in the figure) at the position of the common ground electrode 233a or the signal common ground electrode 232 corresponding to the focusing magnet. The orthographic projection of the through hole on the Hall wafer array 110 is circular or elliptical, and the common ground electrode 233a or the signal common ground electrode 232 is led out through the circular or elliptical through hole. If the signal common ground electrode 232 or the common ground electrode 233b extends to the periphery of the four magnetic sensing parts 10, there is no need to reserve a through hole on the focusing magnet 30, but an insulating layer needs to be set between the focusing magnet 30 and the Hall wafer array 110.

[0055] Another way is to first manufacture the focusing magnet 30, and then install the focusing magnet 30 on the Hall wafer array 110. For this method of manufacturing the focusing magnet 30, it is preferred to set the common ground electrode 233a or the signal common ground electrode 232 at the center position of the four magnetic sensing parts 10, and open a through hole at the position of the focusing magnet 30 corresponding to the common ground electrode 233a or the signal common ground electrode 232. By opening the through hole on the focusing magnet 30, on the one hand, it plays a role of alignment, and on the other hand, it can also lead out the common ground electrode 233a or the signal common ground electrode 232. Preferably, the through hole in this embodiment has an elliptical projection on the Hall wafer array 110. Due to the directionality of the ellipse and the involute design of the through hole, the focusing magnet will be automatically placed at the designated center position and angle within the normal error range of mounting, thereby reducing the installation error.

[0056] Continue to refer Figure 1-Figure 6 In one embodiment, the projection of the focusing magnet 30 on the Hall wafer array 110 is a regular N-gon, where N is an even number greater than or equal to 4. Specifically, Figure 1 ,and Figure 3-Figure 5 As shown, the projection of the focusing magnet 30 on the Hall wafer array 110 is a regular quadrilateral; Figure 6As shown, the projection of the focusing magnet 30 on the Hall wafer array 110 is a regular octagon. Furthermore, each side length of the focusing magnet 30 bisects the sensitive central area 15 of the magnetic sensing part 10 covered by it. Furthermore, the thickness of the focusing magnet 30 on the Z-axis is between 20 and 1000 microns. The boundary of the upper projection of the above-mentioned focusing magnet 30 on the magnetic sensing part 10 specifically refers to the side length of the focusing magnet 30 falling into the sensitive central area 15 of the corresponding magnetic sensing part 10.

[0057] refer to Figure 8-Figure 9 In a second aspect, the present application provides a three-dimensional magnetic field sensor, which includes a package 400, a three-dimensional magnetic field detection chip 100, a conditioning circuit 200, and a plurality of pins 300. The three-dimensional magnetic field detection chip 100 and the conditioning circuit 200 are both disposed in the package 400, and the conditioning circuit 200 is electrically connected to the three-dimensional magnetic field detection chip 100; the plurality of pins 300 are symmetrically disposed on opposite sides of the outside of the package 400. The three-dimensional magnetic field detection chip in this embodiment has been described in detail in the previous text, and will not be repeated here.

[0058] In a specific embodiment, a plurality of spaced metal wires 401 are further provided in the package body 400, and the metal wires 401 connect the electrode part 20 and the conditioning circuit 200. Further, in order to better avoid the overlap or partial overlap of the plurality of metal wires and the overlap or partial overlap with the focusing magnet, the plurality of metal wires 401 can be spaced and avoid the focusing magnet 30 by rotating the three-dimensional magnetic field detection chip 100 and / or changing the extension direction of one or more signal electrodes 21 and / or the extension direction of one or more working electrodes 231.

[0059] like Figure 8 As shown, the three-dimensional magnetic field detection chip 100 in the three-dimensional magnetic field sensor is a six-electrode chip structure. The three-dimensional magnetic field sensor can be made into six or eight pins 300. During the installation process, the extension direction of one or more signal electrodes 21 can be changed to allow multiple metal wires 401 to be spaced apart and avoid the magnetic focusing body 30. For example, the signal electrode 21a corresponding to the first magnetic sensing part 10a is extended toward the direction of the fourth magnetic sensing part 10d (specifically shown as extending toward the lower right in the figure). Such a design can avoid the metal wire 401 connected to the signal electrode 21a corresponding to the first magnetic sensing part 10a passing through the magnetic focusing body 30, thereby affecting the accuracy of magnetic field detection. The signal electrode 21d corresponding to the fourth magnetic sensing part 10d and the signal electrode 21b corresponding to the second magnetic sensing part 10b are extended in different directions respectively, so that the metal wire connecting the signal electrode 21d corresponding to the fourth magnetic sensing part 10d and the metal wire connecting the signal electrode 21b corresponding to the second magnetic sensing part 10b are spaced apart to avoid overlapping.

[0060] like Fig. 9As shown, the three-dimensional magnetic field detection chip 100 in the three-dimensional magnetic field sensor is a nine-electrode chip structure. The three-dimensional magnetic field sensor can be made into eight or ten pins 300. During the installation process, the three-dimensional magnetic field detection chip 100 with a nine-electrode chip structure can be rotated 90° counterclockwise as a whole, and the working ground electrode 231c and the signal electrode 21c of the third magnetic sensing part 10c are extended to the lower right. This design avoids the metal wire 401 passing through the magnetic focusing body 30 and affecting the accuracy of magnetic field detection. Then, the signal electrode 21a of the first magnetic sensing part 10a, the signal electrode 21d of the fourth magnetic sensing part 10d, and the working ground electrode 231a shared by the first magnetic sensing part 10a and the fourth magnetic sensing part 10d are extended in different directions respectively, so that the metal wire connecting the fourth magnetic sensing part 10d and the first magnetic sensing part 10a are arranged at intervals to avoid overlap.

[0061] A third aspect of the present application provides a method for detecting magnetic field components based on a three-dimensional magnetic field sensor, the method comprising:

[0062] Respectively obtain the signal voltages output by the four magnetic sensing units 10 and the sensitivity gain coefficients of the four magnetic sensing units 10;

[0063] Based on the conditioning circuit, the signal gain of the magnetic sensing unit is adjusted to obtain equal sensitivity gain coefficients of the two magnetic sensing units 10 arranged at the first diagonal angle on the X-axis; and equal sensitivity gain coefficients of the two magnetic sensing units 10 arranged at the second diagonal angle on the Y-axis;

[0064] According to the signal voltages output by the four magnetic sensing units 10 , the sensitivity gain coefficients of the four magnetic sensing units 10 , the X-axis sensitivity gain coefficient, the Y-axis sensitivity gain coefficient, the Z-axis magnetic field component, the X-axis magnetic field component and the Y-axis magnetic field component are determined.

[0065] The specific calculation process is as follows:

[0066] The first magnetic sensing part 10a and the second magnetic sensing part 10b are sensitive to the X-axis magnetic field and the Z-axis magnetic field. When the magnetic field passes through the first magnetic sensing part 10a and the second magnetic sensing part 10b, the first signal voltage V A and the second signal voltage V B , V A =K1B z +K x1 B x, V B =K2B z -K x2 B x, Where K1 is the sensitivity gain coefficient of the first magnetic sensing unit, K2 is the sensitivity gain coefficient of the second magnetic sensing unit, and K x1 The X-axis sensitivity gain coefficient of the first magnetic sensing unit, K x2X-axis sensitivity gain coefficient of the second magnetic sensing unit.

[0067] The third magnetic sensing unit 10c and the fourth magnetic sensing unit 10d are sensitive to the Y-axis magnetic field and the Z-axis magnetic field. When the magnetic field passes through the third magnetic sensing unit 10c and the fourth magnetic sensing unit 10d, the third signal voltage V C and the fourth signal voltage V D , V C =K3B z +K y1 B y, V D =K4B z -K Y2 B y， Where K3 is the sensitivity gain coefficient of the third magnetic sensing unit, K4 is the sensitivity gain coefficient of the fourth magnetic sensing unit, and K y1 The Y-axis sensitivity gain coefficient of the third magnetic sensing unit, K y2 The Y-axis sensitivity gain coefficient of the fourth magnetic sensing unit.

[0068] When the position of the focusing magnet is very symmetrical with respect to the four magnetic sensing parts, the simplification can be achieved. However, in general, it is difficult to ensure good symmetry, especially when the focusing magnet is installed on the Hall wafer array. The gain of the first magnetic sensing part 10a or the second magnetic sensing part 10b is adjusted by the back-end electrical gain of the signal voltage (a function that all conventional Hall IC conditioning circuits have, so this application will not describe it in detail here), so that K x1 = K x2 = K x , adjust the back-end signal gain of the third magnetic sensing unit 10c or the fourth magnetic sensing unit 10d so that K y1 = K y2 = K y , that is: V A =K1B z +K x B x , V B =K2B z -K x B x , V C =K3B z +K y B y , V D =K4B z -K Y B y ,

[0069] Finally, we can get B by calculation z =(V A +V B +VC +V D ) / (K1+K2+K3+K4), B x =[(K2-K1)B z -(V B -V A )] / 2K x, B y =[(K3-K4)B z -(V C -V D )] / 2K y， The Z-axis magnetic field component, the X-axis magnetic field component and the Y-axis magnetic field component are obtained.

[0070] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with the technology to understand the content of the present application and implement it accordingly, and they cannot be used to limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit of the present application shall be included in the protection scope of the present application.

Claims

1. A three-dimensional magnetic field detection chip, characterized in that: include: A Hall wafer array, wherein the Hall wafer array is a continuous whole obtained by cutting the same wafer as a whole, and comprises at least four magnetic sensing parts and electrode parts electrically connected to the four magnetic sensing parts, wherein the four magnetic sensing parts are arranged in a rectangular array, the working current directions of the two diagonally arranged magnetic sensing parts are orthogonal, and the first diagonal line between the two magnetic sensing parts arranged at a first diagonal and the second diagonal line between the two magnetic sensing parts arranged at a second diagonal are orthogonal to each other; A focusing magnet is covered on the Hall wafer array, and its orthographic projection on the Hall wafer array covers the sensitive central area of ​​each of the magnetic sensing parts. The boundary of the orthographic projection of the focusing magnet on the two magnetic sensing parts arranged at the first diagonal is perpendicular to the first diagonal line, and the boundary of the orthographic projection of the focusing magnet on the two magnetic sensing parts arranged at the second diagonal line is perpendicular to the second diagonal line. The focusing magnet is inclined at 45° to the at least four magnetic sensing parts.

2. The three-dimensional magnetic field detection chip according to claim 1, characterized in that: The positive projection of the magnetic focusing body on the Hall wafer array is a regular N-gon, where N is an even number greater than or equal to 4; The length of each side of the magnetic focusing body equally divides the induction area of ​​the magnetic induction part covered by the magnetic focusing body.

3. The three-dimensional magnetic field detection chip according to claim 1, characterized in that: The thickness of the magnetizing body in the z-axis direction is between 20 and 1000 microns.

4. The three-dimensional magnetic field detection chip according to claim 1, characterized in that: The electrode comprises: At least four signal electrodes are respectively arranged at the end of each magnetic sensing portion; A working positive electrode connected to the four magnetic induction parts; and a ground electrode, wherein the ground electrode includes a common ground electrode, or the ground electrode includes at least three working ground electrodes and one signal common ground electrode.

5. The three-dimensional magnetic field detection chip according to claim 4, characterized in that: The common ground electrode or the signal common ground electrode is arranged at the center position of the four magnetic sensing parts. The common ground electrode or the signal common ground electrode comprises a buffer layer extending in the z-axis direction and an electrode layer arranged on the buffer layer. The magnetic concentrator is provided with a through hole through which the common ground electrode or the signal common ground electrode can pass.

6. The three-dimensional magnetic field detection chip according to claim 5, characterized in that: The projection of the through hole on the Hall wafer array is circular or elliptical.

7. The three-dimensional magnetic field detection chip according to claim 4, characterized in that: The common ground electrode or the signal common ground electrode extends to the periphery of the four magnetic sensing parts; An insulating layer is arranged between the magnetic focusing body and the Hall wafer array.

8. A three-dimensional magnetic field sensor, characterized in that: Including a package body; The three-dimensional magnetic field detection chip according to any one of claims 1 to 7, which is disposed in the package; A conditioning circuit, which is disposed in the package and electrically connected to the three-dimensional magnetic field detection chip; A plurality of pins are symmetrically arranged on two opposite sides of the outside of the package body.

9. The three-dimensional magnetic field sensor according to claim 8, characterized in that: A plurality of metal wires arranged at intervals are also arranged in the package, and the metal wires connect the electrode part and the conditioning circuit.

10. A method for detecting magnetic field components based on the three-dimensional magnetic field sensor according to claim 8 or 9, characterized in that: include: Acquire signal voltages output by four magnetic induction units and sensitivity gain coefficients of the four magnetic induction units; Adjust the signal gain of the magnetic sensing unit based on the conditioning circuit to obtain equal sensitivity gain coefficients of the two magnetic sensing units arranged at a first diagonal angle on the X-axis and equal sensitivity gain coefficients of the two magnetic sensing units arranged at a second diagonal angle on the Y-axis; According to the signal voltages output by the four magnetic induction units, the sensitivity gain coefficients of the four magnetic induction units, the X-axis sensitivity gain coefficient and the Y-axis sensitivity gain coefficient, the Z-axis magnetic field component, the X-axis magnetic field component and the Y-axis magnetic field component are obtained.

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