A differential 3D Hall sensor device

Abstract

The present application relates to the field of magnetic sensing technology, and in particular to a differential 3D Hall sensor device, comprising: a first Hall pair, comprising two first Hall elements spaced apart and differentially connected in parallel along a first direction axis, for detecting a magnetic field in a first direction; a second Hall pair, comprising two second Hall elements spaced apart and differentially connected in parallel along a second direction axis, for detecting a magnetic field in a second direction, the first direction axis and the second direction axis being orthogonal, and the first direction and the second direction being located in a Hall plane; a third Hall pair, comprising two third Hall elements spaced apart and differentially connected in parallel along a first direction axis or a second direction axis, for detecting a magnetic field in a third direction, and the third direction being orthogonal to the Hall plane; a magnetic concentrating layer, superimposed on the surface where the first Hall pair and the second Hall pair are located, and the projection of the magnetic concentrating layer on the Hall plane at least partially covers the first Hall pair and the second Hall pair. The present application can effectively reduce process difficulty and manufacturing cost, and improve performance.

Description

Technical Field

[0001] The present application relates to the field of magnetic sensing technology, and in particular to a differential 3D Hall sensor device. Background Art

[0002] 3D Hall sensor devices are used in scenarios that require three-axis magnetic field detection. They have the potential to realize coil geomagnetic field and current detection at a relatively low cost, and can be widely used in the field of emerging electronic devices. In order to avoid crosstalk between the plane magnetic field and the Z-axis magnetic field detection, existing Hall sensor devices usually separate the sensitive elements for Z-axis detection from the sensitive elements for plane detection to improve the detection accuracy of the Z-axis sensitive elements. However, this method not only wastes chip area, but also increases the difficulty of device preparation. Summary of the invention

[0003] In view of the above problems in the prior art, the present application provides a differential 3D Hall sensor device, and the specific technical solution is as follows: On the one hand, the present application provides a differential 3D Hall sensor device, and the differential 3D Hall sensor device includes:

[0004] A first Hall pair, comprising two first Hall elements spaced apart along a first direction axis and differentially connected in parallel, for detecting a magnetic field in a first direction;

[0005] A second Hall pair, comprising two second Hall elements spaced apart and differentially connected in parallel along a second direction axis, for detecting a magnetic field in a second direction, wherein the first direction axis and the second direction axis are orthogonal, and the first direction and the second direction are located in a Hall plane;

[0006] A third Hall pair, comprising two third Hall elements spaced apart along the first direction axis or the second direction axis and connected in anti-differential parallel connection, for detecting a magnetic field in a third direction, wherein the third direction is orthogonal to the Hall plane;

[0007] The magnetic focusing layer is stacked on the surface where the first Hall pair and the second Hall pair are located, and the projection of the magnetic focusing layer on the Hall plane at least partially covers the first Hall pair and the second Hall pair.

[0008] In some embodiments, a preset pattern formed by the first Hall pair and the second Hall pair is symmetrical about the first direction axis and the second direction axis.

[0009] In some embodiments, if the third Hall pair is arranged with intervals along the first direction axis, the two third Hall elements in the third Hall pair are symmetrical about the second direction axis; if the third Hall pair is arranged with intervals along the second direction axis, the two third Hall elements in the third Hall pair are symmetrical about the first direction axis.

[0010] In some embodiments, the first Hall pair and the second Hall pair form a planar differential detection component for detecting a planar magnetic field.

[0011] In some embodiments, the sensing regions of the first Hall element, the second Hall element, and the third Hall element are arranged in the same plane.

[0012] In some embodiments, the sensing area of ​​the first Hall element is a symmetrical structure with respect to the first direction and / or the second direction.

[0013] In some embodiments, the sensing region of the second Hall element is a structure symmetrical with respect to the second direction and / or the first direction.

[0014] In some embodiments, the sensing area of ​​the third Hall element is a structure that is symmetrical about the first direction and / or symmetrical about the second direction.

[0015] In some embodiments, the third Hall pair is disposed between the two first Hall elements of the first Hall pair.

[0016] In some embodiments, the third Hall pair is disposed between the two second Hall elements of the second Hall pair.

[0017] In some embodiments, the first Hall pair is disposed between the two third Hall elements of the third Hall pair.

[0018] In some embodiments, the second Hall pair is disposed between the two third Hall elements of the third Hall pair.

[0019] In some embodiments, the orthographic projection of the magnetic focusing layer on the Hall plane at least covers the sensing center of the first Hall element and the sensing center of the second Hall element.

[0020] In some embodiments, the orthographic projection of the magnetic focusing layer on the Hall plane covers the sensing area of ​​the first Hall element and the sensing area of ​​the second Hall element.

[0021] In some embodiments, the thickness of the magnetic focusing layer is 5-500 μm.

[0022] In some embodiments, if the third Hall pair is located between the two first Hall elements of the first Hall pair or between the two second Hall elements of the second Hall pair, the orthographic projection of the magnetic focusing layer on the Hall plane covers the third Hall element.

[0023] In some embodiments, if the first Hall pair or the second Hall pair is located between the two third Hall elements of the third Hall pair, the third Hall pair is located outside the orthographic projection area of ​​the magnetic focusing layer on the Hall plane.

[0024] In some embodiments, the magnetic focusing layer is formed based on a photolithography process.

[0025] In some embodiments, the center of the orthographic projection of the magnetic focusing layer on the Hall plane coincides with the symmetry center of the first Hall pair and the symmetry center of the second Hall pair.

[0026] In some embodiments, the orthographic projection of the magnetic focusing layer on the Hall plane is symmetrical about the first direction axis and the second direction axis.

[0027] In some embodiments, the orthographic projection of the magnetic focusing layer on the Hall plane is rotationally symmetric about the first direction axis and the second direction axis.

[0028] In some embodiments, the magnetic concentrating layer is formed based on a mounting process;

[0029] The differential 3D Hall sensor device also includes a conditioning circuit, which is used to use the first magnetic induction voltage signal output by the first Hall pair, the second magnetic induction voltage signal of the second Hall pair, and the third magnetic induction voltage signal of the third Hall pair as inputs, perform a three-axis magnetic field calculation combined with the interference magnetic field of the magnetic focusing layer, and obtain the calculation results of the magnetic field components in the first direction, the second direction, and the third direction.

[0030] In some embodiments, the working positive electrodes or the working negative electrodes of the two first Hall elements of the first Hall pair and the two second Hall elements of the second Hall pair are connected in a co-linear manner.

[0031] On the other hand, the present application provides a 3D Hall chip, wherein the 3D Hall chip includes the differential 3D Hall sensor device as described above.

[0032] On the other hand, the present application provides an electronic device, the electronic device comprising the differential 3D Hall sensor device as described above. Based on the above technical solution, the present application has the following beneficial effects:

[0033] The differential 3D Hall sensor device of the present application is provided with a first Hall pair for detecting a magnetic field in a first direction, a second Hall pair for detecting a magnetic field in a second direction, and a third Hall pair for detecting a magnetic field in a third direction, wherein the two first Hall elements of the first Hall pair are differentially connected in parallel, the two second Hall elements of the second Hall pair are differentially connected in parallel, and the two third Hall elements of the third Hall pair are anti-differentially connected in parallel, and a magnetic focusing layer is further provided on the first Hall pair and the second Hall pair to deflect the magnetic field to achieve the purpose of planar magnetic field detection. At the same time, through the anti-differentially parallel third Hall pair, not only the Z-axis magnetic field detection is realized, but also the inter-axis signal interference and process cost of the planar Hall detection can be effectively reduced, the inter-axis suppression ratio can be improved, and a highly integrated, miniaturized, low-cost, anti-interference and high inter-axis isolation 3D Hall sensor device is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments or prior art descriptions. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 : A top view of the structure of a differential 3D Hall sensor device provided in an embodiment of the present application;

[0036] Figure 2 : A structural side cross-sectional view of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0037] Figure 3 : A top view of the structure of a differential 3D Hall sensor device provided in an embodiment of the present application;

[0038] Figure 4 : A top view of the structure of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0039] Figure 5 : A top view of the structure of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0040] Figure 6 : A top view of the structure of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0041] Figure 7 : A top view of the structure of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0042] Figure 8 : A top view of the structure of another differential 3D Hall sensor device provided in an embodiment of the present application;

[0043] Fig. 9 : A top view of the structure of a 3D Hall chip provided in an embodiment of the present application;

[0044] Fig.10 : A top view of the structure of another 3D Hall chip provided in an embodiment of the present application;

[0045] Fig.11 : A top view of the structure of another 3D Hall chip provided in an embodiment of the present application;

[0046] Figure numerals: 101 - first Hall element, 102 - second Hall element, 103 - third Hall element, 104 - magnetic focusing layer, 105 - electrode structure, 106 - pad, 201 - conditioning circuit, 202 - division analog circuit, 203 - adjustable gain analog circuit. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0048] It should be noted that in the description of the present application, for the following defined terms, unless a different definition is given in the claims or elsewhere in this specification, these definitions should be applied. All numerical values, whether or not explicitly indicated, are defined herein as being modified by the term "about". The term "about" generally refers to a numerical range that a person of ordinary skill in the art would consider to be equivalent to the stated value to produce substantially the same properties, functions, results, etc. A numerical range indicated by a low value and a high value is defined to include all numerical values ​​included in the numerical range and all subranges included in the numerical range.

[0049] It should be noted that, in the description of the present application, the terms "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0050] It should be noted that, in the description of the present application, the meaning of the terms "on", "above", "above", and "above" should be interpreted in the broadest sense, meaning that the description containing these terms is interpreted as "the component can be set on another component in direct contact, or there can be an intermediate component or layer between the components". In addition, for the convenience of description, the present application may also use spatial relative terms such as "under", "below", "under", "on", "above", "above", "lower", "upper", etc. to describe the relationship between an element or component and another element or component shown in the drawings. In addition to the orientations described in the figures, the spatially relative terms are also intended to cover different orientations of the device in use or operation. The device can be oriented in other ways (rotated 90° or in other orientations), and the spatially relative descriptors used in the present application can be interpreted accordingly.

[0051] The term "layer" as used in this application refers to a portion of a material that includes an area with a certain thickness. A layer can extend over the entire underlying or superstructure, or can extend over a local area of ​​the underlying or superstructure. In addition, a layer can be an area of ​​a homogeneous or inhomogeneous continuous structure, whose thickness is less than the thickness of the continuous structure. For example, a layer can be located between the top and bottom surfaces of the continuous structure or between any pair of horizontal planes therebetween. A layer can extend horizontally, vertically and / or along a tapered surface. A layer can include multiple layers.

[0052] It should be understood that the definitions of “consistent”, “perpendicular”, “orthogonal”, etc. used in this application refer to basic consistency or basic perpendicularity that satisfies process errors, etc., and do not refer to absolute consistency or absolute perpendicularity in the physical sense.

[0053] It should be understood that the “surface”, “plane”, such as “first surface”, “second surface”, etc. used in this application refer to the XY plane of magnetic field detection, corresponding to the XY plane of Hall detection of the differential 3D Hall sensor device, “plane magnetic field” refers to the magnetic field in a direction parallel to the XY plane, “first direction” and “first direction” refer to the X direction or Y direction, and “thickness direction”, “longitudinal direction” or “third direction” refers to the Z direction relative to the XY plane.

[0054] The following combination Figure 1-11 The differential 3D Hall sensor device of the present application is introduced. It can be understood that the differential 3D Hall sensor device in the drawings is only a technical solution of a specific embodiment of the present application, and the differential 3D Hall sensor device of the present application may include fewer or more structural features, and is not limited to the device structure described in the drawings.

[0055] refer to Figure 1-11The differential 3D Hall sensor device includes a first Hall pair, including two first Hall elements 101 arranged at intervals along a first direction axis and differentially connected in parallel, for detecting a magnetic field in a first direction; a second Hall pair, including two second Hall elements 102 arranged at intervals along a second direction axis and differentially connected in parallel, for detecting a magnetic field in a second direction, the first direction axis and the second direction axis are orthogonal, and the first direction and the second direction are located in a Hall plane.

[0056] Specifically, the first direction and the second direction may be an X direction and a Y direction, respectively, and the first direction axis and the second direction axis may be an X axis and a Y axis, respectively.

[0057] Specifically, the first Hall element 101 and the second Hall element 102 are elements capable of realizing magnetic field detection based on the Hall effect, and the first Hall pair and the second Hall pair form a planar differential detection component, and the first Hall pair and the second Hall pair are used to detect a planar two-dimensional magnetic field by a differential detection method. In this way, not only the interference of the Hall voltage signal in the first direction and the second direction is reduced, but also the zero bias and zero drift effect of the signal is reduced.

[0058] In a possible implementation, the preset pattern formed by the first Hall pair and the second Hall pair is symmetrical about the first direction axis and the second direction axis to reduce the calibration and detection complexity of the planar magnetic field detection. Specifically, the preset pattern refers to the pattern formed by the arrangement of each first Hall element 101 and each second Hall element 102. Preferably, reference Figure 1 and Figure 3-11 The preset pattern is a cross shape, and the first Hall pair in the first direction and the second Hall pair in the second direction are arranged in a cross.

[0059] Specifically, the two first Hall elements 101 in the first Hall pair are symmetrically arranged about the second direction axis, and the two second Hall elements 102 in the second Hall pair are symmetrically arranged about the first direction axis. In this way, the calibration and detection complexity of the first direction magnetic field component and the second magnetic field component are reduced through the symmetrical arrangement, thereby improving the accuracy of magnetic field detection.

[0060] Specifically, when there are two or more first Hall pairs, each first Hall pair is coaxially arranged in sequence along the first direction, and the symmetry axes of each first Hall pair coincide. Each first Hall pair serves as a backup for each other, and each first Hall pair in the first direction outputs its own Hall voltage signal, which can realize result verification, detection test, etc. of any first Hall pair, thereby improving the accuracy of magnetic field detection in the first direction.

[0061] Specifically, when there are two or more second Hall pairs, each second Hall pair is coaxially arranged in sequence along the second direction, and the symmetry axes of each second Hall pair coincide. Each second Hall pair serves as a backup detection for each other, and each second Hall pair in the second direction outputs its own Hall differential voltage signal, which can realize result verification, detection test, etc. of any second Hall pair, thereby improving the accuracy of magnetic field detection in the second direction.

[0062] In a possible implementation, the symmetry center of each first Hall pair coincides with the symmetry center of each second Hall pair, that is, the intersection of the symmetry axis of the first Hall pair and the symmetry axis of the second Hall pair is the center of the preset pattern. By setting the first Hall pair and the second Hall pair symmetrically and with the centers overlapping, accurate detection of the magnetic field in the first direction and the second direction can be achieved, and signal calibration and output calculation are simple.

[0063] In a possible implementation, the structure and material of the sensing area of ​​the two first Hall elements 101 in the first Hall pair are consistent, and the structure and material of the sensing area of ​​the two second Hall elements 102 in the second Hall pair are consistent. In a preferred implementation, the structure and material of the sensing area of ​​each first Hall element 101 are consistent with the structure and material of the sensing area of ​​each second Hall element 102, so as to reduce the difficulty of preparation. The sensing area refers to the effective device area in the Hall element for responding to the magnetic field, that is, the device area in the Hall element that is sensitive to the magnetic field and can form a magnetic induction signal, such as Figure 1 The gray cross area is shown. The same structure and material settings make the Hall coefficients of the Hall elements consistent, which is convenient for magnetic field detection calibration and calculation.

[0064] The differential 3D Hall sensor device further includes a third Hall pair, including two third Hall elements 103 spaced apart along the first direction axis or the second direction axis and connected in anti-differential parallel connection, for detecting a magnetic field in a third direction, which is orthogonal to the Hall plane.

[0065] Specifically, the third direction may be a Z direction perpendicular to the Hall plane (XY plane). The third Hall element 103 is an element capable of realizing magnetic field detection based on the Hall effect, and the third Hall pair forms a Z-axis differential detection component for detecting the Z-axis magnetic field by a differential detection method. In this way, not only the interference of the Hall voltage signal of the XY axis is reduced, but also the zero bias and zero drift effect of the signal is reduced.

[0066] The differential 3D Hall sensor device further includes a magnetic focusing layer 104 stacked on the surface where the first Hall pair and the second Hall pair are located, and the projection of the magnetic focusing layer 104 on the Hall plane at least partially covers the first Hall pair and the second Hall pair.

[0067] Specifically, the magnetic focusing layer 104 is made of a high magnetic permeability material and is stacked on each first Hall element 101 and each second Hall element 102 to achieve a magnetic focusing effect of the planar magnetic field, improve the magnetic field detection gain in the first direction and the second direction, and thereby improve the sensitivity of the first direction magnetic field component detection of the first Hall pair and the second direction magnetic field component detection of the second Hall pair, as well as improve the sensitivity of the planar magnetic field detection and the output signal quality.

[0068] In summary, the differential 3D Hall sensor device of the present application is provided with a first Hall pair for detecting a magnetic field in a first direction, a second Hall pair for detecting a magnetic field in a second direction, and a third Hall pair for detecting a magnetic field in a third direction, wherein the two first Hall elements 101 of the first Hall pair are differentially connected in parallel, the two second Hall elements 102 of the second Hall pair are differentially connected in parallel, and the two third Hall elements 103 of the third Hall pair are anti-differentially connected in parallel, and a magnetic focusing layer 104 is also provided on the first Hall pair and the second Hall pair to deflect the magnetic field to achieve the purpose of planar magnetic field detection. At the same time, through the anti-differentially parallel third Hall pair, not only the Z-axis magnetic field detection is realized, but also the inter-axis signal interference and process cost of the planar Hall detection can be effectively reduced, the inter-axis suppression ratio can be improved, and a highly integrated, miniaturized, low-cost, anti-interference and high inter-axis isolation 3D Hall sensor device is realized.

[0069] In a possible implementation manner, the thickness of the magnetic focusing layer 104 is 5-500 μm. By setting the thickness as above, the magnetic focusing effect is ensured while avoiding affecting the subsequent metal wire bonding process.

[0070] In a possible implementation, the magnetic focusing layer 104 is formed based on a photolithography process and is a stack located on the first Hall pair and the second Hall pair to achieve sub-micron level alignment accuracy, improve the position accuracy of the magnetic focusing layer 104, and make the crosstalk introduced by the alignment error negligible.

[0071] In a preferred embodiment, reference Figure 1 and Figure 6 The center of the orthographic projection of the magnetic focusing layer 104 on the Hall plane coincides with the symmetry center of the first Hall pair and the symmetry center of the second Hall pair, that is, the center of the orthographic projection of the magnetic focusing layer 104 on the Hall plane coincides with the center of the preset pattern.

[0072] In a preferred embodiment, reference Figure 1 and Figure 6, the positive projection of the magnetic concentrating layer 104 on the Hall plane is symmetrical about the first direction axis and the second direction axis, that is, the positive projection shape of the magnetic concentrating layer 104 is a figure symmetrical about the first direction and the second direction axis. By symmetrically arranging the magnetic concentrating layer 104 above the first Hall pair and the second Hall pair of planar magnetic field detection, combined with the symmetrical arrangement of the first Hall pair about the second direction, and the symmetrical arrangement of the second Hall pair about the first direction, that is, the planar magnetic field detection component is overall symmetrical and consistent in the X and Y directions, the magnetic concentrating effect of the magnetic concentrating layer 104 on the two first Hall elements 101 of the first Hall pair is consistent, and the magnetic concentrating effect on the two second Hall elements 102 of the second Hall pair is also consistent. At the same time, the influence on the Z-axis magnetic field detection of the third Hall element 103 is also easy to calibrate and eliminate due to the symmetry, thereby reducing crosstalk between axes.

[0073] In a possible implementation, the orthographic projection of the magnetic focusing layer on the Hall plane covers at least the sensing center of the first Hall element 101 and the sensing center of the second Hall element 102, where the sensing center refers to the center of the sensing area of ​​the Hall element, to enhance the magnetic focusing effect. The orthographic projection of the magnetic focusing layer 104 on the Hall plane covers the sensing area of ​​the first Hall element 101 and the sensing area of ​​the second Hall element 102, that is, the orthographic projection of the magnetic focusing layer 104 exceeds the sensing center to fully cover the sensing area.

[0074] In a preferred embodiment, the orthographic projection of the magnetic focusing layer 104 on the Hall plane is rotationally symmetric about the first direction axis and the second direction axis, that is, the orthographic projection shape of the magnetic focusing layer 104 is a rotationally symmetric figure. In combination with the preset figure being rotationally symmetric about the first direction axis and the second direction axis (that is, it is still symmetric after rotating 90°, and the X and Y directions are completely symmetric), not only the gain of the differential signal of the plane magnetic field detection to the magnetic field is consistent, but also the influence of the magnetic focusing layer 104, the first Hall pair and the second Hall pair on the Z axis is theoretically completely eliminated due to the symmetry. Even if there is a certain amount of crosstalk, the influence of the X axis and the Y axis on the Z direction detection is consistent, which is easy to calibrate and remove.

[0075] For example, reference Figure 1-11 The shape of the magnetic focusing layer 104 can be a rectangle, a circle, a regular even polygon, etc.

[0076] In a preferred embodiment, the magnetic concentrating layer covers the sensing center of the first Hall element 101 and the sensing center of the second Hall element 102, and for the first Hall element 101, the outer edge of the orthographic projection of the magnetic concentrating layer 104 on the plane exceeds the length of the sensing area of ​​the first Hall element 101 in the first direction, and does not exceed the first preset ratio of the length of the sensing area of ​​the first Hall element 101 in the first direction, and the first preset ratio is 1 / 4-2 / 5; for the second Hall element 102, the outer edge of the orthographic projection of the magnetic concentrating layer 104 on the plane exceeds the length of the sensing area of ​​the second Hall element 102 in the second direction, and does not exceed the second preset ratio of the length of the sensing area of ​​the second Hall element 102 in the second direction, and the second preset ratio is 1 / 4-2 / 5. It should be noted that the length of the sensing area exceeding the first Hall element 101 and the second Hall element 102 refers to the interval between the outer edge and the outer edge of the sensing area. Preferably, the first preset ratio is 1 / 3; the second preset ratio is 1 / 3. The outer edge of the magnetic concentrating layer 104 refers to the edge of the magnetic concentrating layer 104 that is away from the center of the magnetic concentrating layer 104. In this way, the magnetic focusing layer 104 satisfies the aforementioned symmetrical structure setting and its outer edge exceeds the sensing center of each first Hall element 101 and the second Hall element 102 in the direction away from the center of the magnetic focusing layer 104, so as to enhance the magnetic field focusing and deflection effects. Meanwhile, the outer edge does not exceed 1 / 4-2 / 5 of the length of the Hall element itself for planar magnetic field detection, so as to avoid the differential 3D Hall sensor device being too large and the weakening of the magnetic focusing effect.

[0077] It can be understood that the third Hall pair can be arranged along the first direction axis, or along the second direction axis, or the third Hall pair can be arranged on both the first direction axis and the second direction axis to provide backup detection for each other.

[0078] In a possible implementation, if the third Hall pair is arranged at intervals along the first direction axis, the two third Hall elements 103 in the third Hall pair are symmetrical about the second direction axis; if the third Hall pair is arranged at intervals along the second direction axis, the two third Hall elements 103 in the third Hall pair are symmetrical about the first direction axis. In this way, combined with the reverse differential parallel arrangement of the two third Hall elements 103 and the symmetrical arrangement of the magnetic focusing layer 104, reference Figure 3-4 and Figure 7-11 , so that the third Hall pair only senses the Z-axis magnetic field in the same direction, ensuring the device integration while achieving accurate detection of planar magnetic fields and Z-axis magnetic fields.

[0079] In some embodiments, the third Hall pair is located outside the preset pattern, that is, outside the area surrounded by the first Hall pair and the second Hall pair. Figure 1-5 and Figure 9-11The first Hall pair is arranged between the two third Hall elements 103 of the third Hall pair; and / or the second Hall pair is arranged between the two third Hall elements 103 of the third Hall pair. This is beneficial to the wiring arrangement of the Hall device and simplifies the preparation of the subsequent wiring layer.

[0080] Specifically, if the first Hall pair or the second Hall pair is located between the two third Hall elements 103 of the third Hall pair, the third Hall pair is located outside the positive projection area of ​​the magnetic focusing layer 104 on the Hall plane to further weaken the signal interference of the magnetic focusing layer 104 on the third Hall pair.

[0081] In some embodiments, the third Hall pair is located in a preset pattern, that is, located in the area surrounded by the first Hall pair and the second Hall pair. Figure 6-8 The third Hall pair is disposed between the two first Hall elements 101 of the first Hall pair; and / or the third Hall pair is disposed between the two second Hall elements 102 of the second Hall pair. This is conducive to further miniaturizing the device size and improving the integration of the Hall device.

[0082] Specifically, if the third Hall pair is located between the two first Hall elements 101 of the first Hall pair or between the two second Hall elements 102 of the second Hall pair, the orthographic projection of the magnetic focusing layer 104 on the Hall plane covers the third Hall element 103 to maintain the continuous setting of the magnetic focusing layer 104 and simplify the preparation of the magnetic focusing layer 104. Combined with the symmetrical setting of the magnetic focusing layer 104 on the first direction axis and the second direction axis, the influence of the interfering magnetic fields in the X and Y directions on the third Hall pair is offset, and the output of the third Hall pair is still only affected by the Z-direction magnetic field component, thereby achieving accurate detection of the Z-direction magnetic field component.

[0083] In a possible implementation manner, the sensing regions of the first Hall element, the second Hall element 102 and the third Hall element 103 are coplanarly arranged, and the coplanar first Hall pair, the second Hall pair and the third Hall pair form a planar 3D magnetic field detection component.

[0084] In a possible implementation manner, the sensing area of ​​the first Hall element is a symmetrical structure with respect to the first direction and / or the second direction.

[0085] In a possible implementation manner, the sensing area of ​​the second Hall element is a structure symmetrical about the second direction and / or the first direction; in a possible implementation manner, the sensing area of ​​the third Hall element is a structure symmetrical about the first direction and / or about the second direction.

[0086] In this way, the sensing areas of the Hall elements are set symmetrically about the X direction and the Y direction, so that the magnetic field intensity sensed by the sensing area when detecting the magnetic field component has symmetry and consistency, so as to simplify the magnetic field detection calculation and improve the accuracy of magnetic field detection.

[0087] In a possible implementation manner, the sensing region of the first Hall element 101 is symmetrical about the first direction and / or the second direction, and the sensing region of the first Hall element 101 is a rotationally symmetrical structure, and the rotation angle of the rotational symmetry may be 90°.

[0088] In a possible implementation manner, the sensing region of the second Hall element 102 is symmetrical about the first direction and / or the second direction, and the sensing region of the second Hall element 102 is a rotationally symmetrical structure, and the rotation angle of the rotational symmetry may be 90°.

[0089] In a possible implementation manner, the sensing region of the third Hall element 103 is symmetrical about the first direction and / or the second direction, and the sensing region of the third Hall element 103 is a rotationally symmetrical structure, and the rotation angle of the rotational symmetry may be 90°.

[0090] For example, the sensing area of ​​the first Hall element 101, the sensing area of ​​the second Hall element 102, and the sensing area of ​​the third Hall element 103 may be as follows: Figure 1 The cross shape in the figure can also be a circle or other shapes that satisfy the above symmetry conditions, which are not enumerated here.

[0091] In a possible implementation, the first Hall element 101, the second Hall element 102 and the third Hall element 103 further include an electrode structure 105 connected to the sensing area, specifically including a working positive electrode, a working negative electrode and a signal electrode, which are respectively used for electrical connection of the Hall element and output of the magnetic induction signal.

[0092] In some embodiments, the two first Hall elements 101 of the first Hall pair and the working positive electrodes or the working negative electrodes of the two second Hall elements 102 of the second Hall pair are connected in a collinear manner. In this way, electrodes of the same polarity are connected in a collinear manner to simplify the wiring of the IC circuit. Specifically, the Hall device further includes a plurality of pads 106 to respectively connect the working positive electrode, the working negative electrode and the signal electrode of the Hall element.

[0093] In some embodiments, the working positive electrode or the working negative electrode of the third Hall element 103 is connected in line with the electrode structure 105 of the first Hall element 101, or is connected in line with the electrode structure 105 of the second Hall element 102, so as to further simplify the IC circuit wiring.

[0094] In one embodiment, reference Figure 1The differential 3D Hall sensor device includes four Halls arranged in a cross on a plane and a magnetic concentrating layer 104 above them. Hall A and Hall B arranged along the first direction axis (X axis) form a first Hall pair. The sensing areas of Hall A and Hall B are symmetrically arranged about the Y axis and differentially connected in parallel to detect the X-axis magnetic field; Hall C and Hall D arranged along the second direction axis (Y axis) form a second Hall pair. The sensing areas of Hall C and Hall D are symmetrically arranged about the X axis and differentially connected in parallel to detect the Y-axis magnetic field. The X axis is perpendicular to the Y axis and intersects at point O. The preset pattern formed by the first Hall pair and the second Hall pair is symmetrical about the X axis and the Y axis. The magnetic concentrating layer 104 is stacked on Hall AD and parallel to the Hall plane, and is made of high magnetic permeability material.

[0095] Furthermore, the differential 3D Hall sensor device further includes Hall E and Hall F spaced apart along the X-axis to form a third Hall pair, wherein the sensing regions of Hall E and Hall F are symmetrically arranged about the Y-axis and are anti-differentially connected in parallel to detect the Z-axis magnetic field. Hall E and Hall F are located outside Hall A and Hall B, respectively.

[0096] Furthermore, the magnetic focusing layer 104 is formed by a photolithography process and has a precise position accuracy. The magnetic focusing layer 104 is arranged symmetrically about the X-axis and the Y-axis. Preferably, the magnetic focusing layer 104 is also rotationally symmetrical about the X-axis and the Y-axis. Figure 1-4 The voltage output by the first Hall pair is only related to the magnetic field difference induction between Hall A and Hall B, and the voltage output by the second Hall pair is only related to the magnetic field difference induction between Hall E and Hall F. Figure 2 , from left to right are Hall E, Hall A, Hall B and Hall F. In the X direction, the spillover magnetic field of the magnetic layer 104 affects Hall E and F in approximately the same direction as that of the adjacent Hall A and B. The magnetic field lines of the magnetic layer 104 are shown in Figure 2 As shown in M1 in the figure, the voltage output between Hall E and Hall F only senses the same direction of the Z-axis magnetic field, and the X-direction magnetic field generates opposite signals to them and cancels them out. The influence of the Y-direction magnetic field also approaches zero due to the symmetrical setting of the magnetic focusing layer 104.

[0097] Further, refer to Figure 3 In the figure, + is the pad 106 connected to the working positive electrode of the Hall, - is the pad 106 connected to the working negative electrode or the ground, and the other pads 106 are the connection pads 106 of the signal electrode. From left to right in the X direction are Hall E, Hall A, Hall B and Hall F, and from top to bottom on the Y axis are Hall C and Hall D. The working positive electrodes of Hall A and Hall B are collinear and electrically connected to the pad 106; the working negative electrodes of Hall AD are collinearly connected to the same pad 106; the working positive electrodes of Hall CE are collinearly connected to the same pad 106. Hall A and Hall B, as well as Hall C and Hall D are differentially connected in parallel, and Hall E and Hall F are anti-differentially connected in parallel. The signal electrodes of Hall A and Hall B output signals VAB , the signal electrodes of Hall C and Hall D output signal V CD , the signal electrodes of Hall E and Hall F output signal V EF Since the signal between AB is proportional to the magnetic field strength in the X direction, and the signal between CD is proportional to the magnetic field strength in the Y direction, the relationship between the magnetic field component B and the Hall voltage signal V is: AB =K x B x , V CD =K y B y , where V AB Represents the Hall voltage signal in the X direction output by Hall A and Hall B, V CD The Hall voltage signal in the Y direction of the Hall C and Hall D terminals is represented, that is, the output of the differential 3D Hall sensor device is V AB , V CD , K is the gain of the Hall voltage to the magnetic field component, that is, it represents the gain of the magnetic field component, K x , K y Respectively represent the magnetic field component gain coefficients in the XY directions.

[0098] Since the electrode connection of Hall EF is reverse differential, the output signal V EF The magnetic field distortion caused by the magnetic concentrating layer 104 in the X direction is eliminated due to symmetry and opposite direction. The magnetic field in the Y-axis direction is also completely symmetrical to the Hall EF, and there is no unidirectional signal. Therefore, the device configuration of this embodiment eliminates the influence of the XY-axis magnetic field on the Hall EF, so V EF Only reflects the z-axis magnetic field in the same direction, V EF =K Z B z , V Z K is the Hall voltage signal in the Z direction output by Hall Z. Z Characterizes the gain coefficient of the magnetic field component in the Z direction. The differential 3D Hall sensor device of this embodiment can be used to form a linear 3D Hall chip, a linear analog 3D Hall chip, or a digital-analog hybrid component. The back-end processing circuit only needs to calibrate and calculate the magnetic field measurement signal with a certain direction and magnitude, obtain the gain coefficient K value, and then use the division circuit to divide V AB , V CD and V EF The three signal voltages are divided by their respective gain coefficients to obtain the magnetic field strength B in three directions. x , B y and B z The division calculation here can be performed using a division analog circuit 202 (refer to Fig.10), which can be achieved by adjusting the coefficients by adjusting the circuit element parameters, or by programming using a mixed analog-to-digital circuit.

[0099] In some embodiments, reference Figure 4 and Figure 8-11 , the pads 106 can also be connected by jumpers (dashed lines in the figure) to simplify wiring. It can be understood that in the above-mentioned jumper structures, at least part of the jumpers can be replaced by back-side line connections based on metal vias to avoid the risk of short circuits caused by too long jumpers and reduce the difficulty of wiring process, thereby improving device stability and reliability.

[0100] In a preferred embodiment, the preset pattern is symmetrical about the X-axis and the Y-axis, and is rotationally symmetrical about the X-axis and the Y-axis. The magnetic concentrating layer 104 is symmetrical about the X-axis and the Y-axis, and is rotationally symmetrical about the X-axis and the Y-axis. The center of the positive projection of the magnetic concentrating layer 104 coincides with the center point O of the preset pattern, and precise positioning ensures that there is no crosstalk between axes. The magnetic concentrating layer 104 can be a square or a positive even polygon or other shapes that satisfy rotational symmetry.

[0101] Preferably, the magnetic field component gain corresponding to the Hall voltage signal of the first Hall pair, the magnetic field component gain corresponding to the Hall voltage signal of the second Hall pair and the magnetic field component gain corresponding to the Hall voltage signal in the third direction are consistent. It can be understood that the magnetic field component gain of the XYZ axis can be consistent by setting the magnetic field focusing layer 104 directly above the preset pattern and setting it to a shape that is symmetrical and rotationally symmetrical about the X-axis and the Y-axis, and then adjusting the rear-end signal amplification gain in the third direction. That is, when a linear magnetic sensitive element is required, K is guaranteed from the design and calibration. x =K y =K z =K, then the output gain of each axis signal is the same, and the analog signal with equal gain can be directly output to represent the respective magnetic field strength, V AB =KB x , V CD =KB y , V EF =KB z In this way, the division operation is avoided in the circuit design, and the output signal is the magnetic field component with the same gain in three axes, which simplifies the circuit and reduces the cost. Figure 4 and Fig.11 In the differential 3D Hall sensor device shown in FIG, the magnetic concentrating layer 104 is a square, a regular octagon or a regular dodecagon, and is completely rotationally symmetric in the XY direction. The gains in the two directions are consistent, and the gain is adjusted by the back-end electronic method of the Z axis to obtain a linear Hall device with the same gain in three axes. It can be understood that, in combination with the rotationally symmetric magnetic concentrating layer setting, optionally, the circuit for calculating the magnetic field component may not be set in the Hall sensor chip with a simplified structure, or an adjustable gain analog 203 (reference Fig.11) circuit to achieve adjustable gain setting in magnetic field detection, thereby improving the applicability and detection performance of the process and devices.

[0102] It should be noted that Figure 9-11 The back-end circuit type in is only a preferred example. The back-end circuit can also have the ability of division calculation and adjustable gain at the same time. The specific structure can be set based on actual needs and is not limited to the exemplified embodiments and drawings. In a possible implementation, the magnetic layer 104 is formed based on a mounting process. Due to the precision limitation of the mounting process, the position of the magnetic layer 104 may be biased, causing its center to deviate from the symmetry center of the preset figure. Correspondingly, the differential 3D Hall sensor device also includes a conditioning circuit 201, which is used to use the first magnetic induction voltage signal output by the first Hall pair, the second magnetic induction voltage signal of the second Hall pair, and the third magnetic induction voltage signal of the third Hall pair as inputs to perform a three-axis magnetic field calculation combined with the interference magnetic field of the magnetic layer 104, and obtain the calculation results of the magnetic field components in the first direction, the second direction, and the third direction. In this way, the interference caused by the offset of the magnetic layer 104 is eliminated by the conditioning circuit 201, and accurate detection of the three-axis magnetic field is achieved.

[0103] In one embodiment, reference Figure 5 The figure includes Hall AF, and the arrangement position of each Hall element is similar to Figure 1-4 The magnetic field deflected by the magnetic concentrator is no longer symmetrical. The interference magnetic field of the X axis at Hall E is weaker than that at Hall F, and the interference signal generated by it is also smaller than that of Hall F. That is, the interference magnetic field signal is not zero, which will be reflected in V EF Similarly, the Z-axis magnetic field also generates different interference signals on Hall AB, and the output signal V AB There is a residual component of the Z axis. There is mutual crosstalk between the X and Z axes. Similarly, the Y axis can also sense the Z axis magnetic field due to the asymmetry of the magnetic focusing layer 104. In addition, although the magnetic focusing layer 104 is asymmetric in the Y direction, in theory the Hall EF can also sense the asymmetric magnetic field introduced by the Y axis. However, due to limited process errors, when the error is more than a dozen microns, for the Hall EF that is more than a few hundred microns away from the magnetic focusing layer 104, the corresponding impact is relatively small, and the interference of the asymmetric magnetic field in the Y direction on the Hall EF can be ignored. Then, considering the installation error, the relationship between each output signal and the magnetic field is: V AB =K 1 B z +K x B x , V CD =K 2 B z +K y B y , V EF =K 0 Bx +K z B z , K 1 B z K is the Z-axis interference of Hall AB, 2 B z is the Z-axis interference on the Hall CD, K 0 B x is the X-axis interference on Hall EF. Further, B z =(K 0 V AB -K x V EF ) / (K 0 K 1 -K x K Z ), B x =(V AB -K 1 B z ) / K x , B y =(V CD -K 2 B z ) / K y , the differential 3D Hall sensor device directly senses the output signal V AB , V CD and V EF , the calculation logic of the above formula is executed by the conditioning circuit 201 to obtain each magnetic field component, such as Fig. 9 shown.

[0104] In summary, the present application provides a differential 3D Hall sensor device with a high-isolation magnetic circuit design, which can be used for 3D Hall chips to achieve high suppression ratio and low drift of inter-axis signals, and the differential detection on the horizontal plane and the Z-axis reverse differential detection make the XYZ axes have strong anti-interference capabilities, and has the advantages of integration, miniaturization, low cost, anti-interference and high inter-axis isolation.

[0105] On the other hand, the present application provides a 3D Hall chip, which includes a differential 3D Hall sensor device as described above. Differential 3D Hall sensor device On the other hand, the present application provides an electronic device, which includes an electronic device made using the above-mentioned differential 3D Hall sensor device or the preparation method of the differential 3D Hall sensor device. The electronic device may include any electronic component such as an integrated circuit, an electronic device, etc. Since the working performance of the differential 3D Hall sensor device is better, the performance of the electronic device is correspondingly improved.

[0106] The electronic device of the embodiment of the present application can be selected from any electronic product or equipment such as a mobile phone, a personal digital assistant (PDA), a tablet computer (pad), a laptop computer, a game console, a television, a video compact disc (VCD), a digital video disc (DVD), a navigator, a camera, a camcorder, a voice recorder, an MP3, an MP4, a handheld game console (PlayStation Portable, PSP), a drone, etc., and can also be any intermediate product of an electronic device made of the above-mentioned differential 3D Hall sensor device.

[0107] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0108] The above description has fully disclosed the specific implementation methods of the present application. It should be pointed out that any changes made by technicians familiar with the field to the specific implementation methods of the present application do not deviate from the scope of the claims of the present application. Accordingly, the scope of the claims of the present application is not limited to the above specific implementation methods.

Claims

1. A differential 3D Hall sensor device, characterized in that: The differential 3D Hall sensor device comprises: A first Hall pair, comprising two first Hall elements spaced apart along a first direction axis and differentially connected in parallel, for detecting a magnetic field in a first direction; A second Hall pair, comprising two second Hall elements spaced apart and differentially connected in parallel along a second direction axis, for detecting a magnetic field in a second direction, wherein the first direction axis and the second direction axis are orthogonal, and the first direction and the second direction are located in a Hall plane; A third Hall pair, comprising two third Hall elements spaced apart along the first direction axis or the second direction axis and connected in anti-differential parallel connection, for detecting a magnetic field in a third direction, wherein the third direction is orthogonal to the Hall plane; The magnetic focusing layer is stacked on the surface where the first Hall pair and the second Hall pair are located, and the projection of the magnetic focusing layer on the Hall plane at least partially covers the first Hall pair and the second Hall pair.

2. The differential 3D Hall sensor device according to claim 1, characterized in that: The differential 3D Hall sensor device satisfies at least one of the following features: The preset pattern formed by the first Hall pair and the second Hall pair is symmetrical about the first direction axis and the second direction axis; If the third Hall pair is arranged with intervals along the first direction axis, the two third Hall elements in the third Hall pair are symmetrical about the second direction axis; if the third Hall pair is arranged with intervals along the second direction axis, the two third Hall elements in the third Hall pair are symmetrical about the first direction axis.

3. The differential 3D Hall sensor device according to claim 1, characterized in that: The differential 3D Hall sensor device satisfies one of the following characteristics: The first Hall pair and the second Hall pair form a planar differential detection component for detecting a planar magnetic field; The sensing areas of the first Hall element, the second Hall element and the third Hall element are arranged on the same plane.

4. The differential 3D Hall sensor device according to claim 1, characterized in that: The differential 3D Hall sensor device satisfies at least one of the following features: The sensing area of ​​the first Hall element is a symmetrical structure with respect to the first direction and / or the second direction; The sensing area of ​​the second Hall element is a symmetrical structure with respect to the second direction and / or the first direction; The sensing area of ​​the third Hall element is a structure that is symmetrical about the first direction and / or symmetrical about the second direction.

5. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: The differential 3D Hall sensor device satisfies at least one of the following features: The third Hall pair is arranged between the two first Hall elements of the first Hall pair; The third Hall pair is arranged between the two second Hall elements of the second Hall pair; The first Hall pair is arranged between the two third Hall elements of the third Hall pair; The second Hall pair is disposed between the two third Hall elements of the third Hall pair.

6. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: The differential 3D Hall sensor device satisfies at least one of the following features: The orthographic projection of the magnetic concentrating layer on the Hall plane at least covers the sensing center of the first Hall element and the sensing center of the second Hall element; The orthographic projection of the magnetic focusing layer on the Hall plane covers the sensing area of ​​the first Hall element and the sensing area of ​​the second Hall element; The thickness of the magnetic concentrating layer is 5-500 μm.

7. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: If the third Hall pair is located between the two first Hall elements of the first Hall pair or between the two second Hall elements of the second Hall pair, the orthographic projection of the magnetic focusing layer on the Hall plane covers the third Hall element; If the first Hall pair or the second Hall pair is located between the two third Hall elements of the third Hall pair, the third Hall pair is located outside the orthographic projection area of ​​the magnetic focusing layer on the Hall plane.

8. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: The differential 3D Hall sensor device satisfies at least one of the following features: The magnetic concentrating layer is formed based on a photolithography process; The center of the orthographic projection of the magnetic focusing layer on the Hall plane coincides with the symmetry center of the first Hall pair and the symmetry center of the second Hall pair; The orthographic projection of the magnetic focusing layer on the Hall plane is symmetrical about the first direction axis and the second direction axis; The orthographic projection of the magnetic focusing layer on the Hall plane is rotationally symmetric about the first direction axis and the second direction axis.

9. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: The magnetic concentrating layer is formed based on a mounting process; The differential 3D Hall sensor device also includes a conditioning circuit, which is used to use the first magnetic induction voltage signal output by the first Hall pair, the second magnetic induction voltage signal of the second Hall pair, and the third magnetic induction voltage signal of the third Hall pair as inputs, to perform a three-axis magnetic field calculation combined with the interference magnetic field of the magnetic focusing layer, and obtain the calculation results of the magnetic field components in the first direction, the second direction, and the third direction.

10. The differential 3D Hall sensor device according to any one of claims 1 to 4, characterized in that: The working positive electrodes or working negative electrodes of the two first Hall elements of the first Hall pair and the two second Hall elements of the second Hall pair are connected in a colinear manner; The working positive electrode or the working negative electrode of the third Hall element is connected in a collinear manner with the electrode structure of the first Hall element, or is connected in a collinear manner with the electrode structure of the second Hall element.

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