Three-axis Hall magnetic sensor

Abstract

The utility model provides a three-axis Hall magnetic sensor. The three-axis Hall magnetic sensor comprises a substrate; the doped well is formed on the substrate and comprises a first doped strip and a second doped strip; the first doped strip extends along a first direction; the second doped strip extends along a second direction vertical to the first direction and is vertically intersected with the first doped strip; the first electrode is formed at the junction of the first doping strip and the second doping strip; the second electrode and the third electrode are at least partially formed in the first doping strip and are positioned on one side of the first electrode; the fourth electrode and the fifth electrode are at least partially formed in the first doping strip and are positioned on the other side of the first electrode; the sixth electrode and the seventh electrode are at least partially formed in the second doping strip and located on one side of the first electrode; and the eighth electrode and the ninth electrode are at least partially formed in the second doping strip and are positioned on the other side of the first electrode. Therefore, detection of a three-axis magnetic field can be realized through a single Hall device.

Description

Technical field

[0001] The utility model relates to the field of magnetic sensors, in particular to a three-axis Hall magnetic sensor. [Background Technology]

[0002] Existing three-axis Hall effect magnetic sensors generally have two implementation options. The first option uses horizontal Hall effect technology, where the initial magnetic field detection direction is perpendicular to the chip surface. This requires a magnetic field steering structure, such as a flux concentrator, to achieve three-axis magnetic field detection. This option requires a large number of horizontal Hall effect units. The second option uses both horizontal and vertical Hall effect units. The horizontal Hall effect unit detects the magnetic field in the Z-axis direction, while the vertical Hall effect unit detects the magnetic field in the X- and Y-axis directions. This also requires multiple Hall effect sensing units. It is impossible to achieve three-axis magnetic field detection using a single Hall effect device.

[0003] Therefore, it is urgent to propose a new technical solution to solve the above problems. [Utility Model Content]

[0004] One of the purposes of the present invention is to provide a three-axis Hall magnetic sensor, which can detect three-axis magnetic fields through a single Hall device.

[0005] According to one aspect of the present invention, the present invention provides a three-axis Hall effect magnetic sensor, which includes: a substrate; a doped well formed on the substrate, wherein the doped well includes a first doped strip extending along a first direction and a second doped strip extending along a second direction perpendicular to the first direction and perpendicularly intersecting the first doped strip; a first electrode formed at the intersection of the first doped strip and the second doped strip; a second electrode and a third electrode at least partially formed in the first doped strip and located on one side of the first electrode, wherein the second electrode and the third electrode are spaced apart from each other along the first direction, and the third electrode is closer to the first electrode than the second electrode; a fourth electrode and a fifth electrode at least partially formed in the first doped strip and located on the other side of the first electrode, wherein the fourth electrode and the fifth electrode are spaced apart from each other along the first direction, and the fourth electrode is closer to the first electrode than the fifth electrode; a sixth electrode and a seventh electrode at least partially formed in the second doped strip and located on one side of the first electrode, wherein the sixth electrode and the seventh electrode are spaced apart from each other along the second direction, and the seventh electrode is closer to the first electrode than the sixth electrode; an eighth electrode and a ninth electrode at least partially formed in the second doped strip and located on the other side of the first electrode, wherein the eighth electrode and the ninth electrode are spaced apart from each other along the second direction, and the eighth electrode is closer to the first electrode than the ninth electrode.

[0006] Compared with the prior art, the present invention utilizes horizontal Hall and vertical Hall technologies to form a single Hall sensing structure, which has a three-axis magnetic field detection function.

Brief Description of the Drawings

[0007] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without inventive work. Among them:

[0008] Figure 1 1 is a schematic top view of the three-axis Hall magnetic sensor in the first embodiment of the present invention;

[0009] Figure 2 for Figure 1 A schematic cross-sectional view of the three-axis Hall magnetic sensor along the section line AA;

[0010] Figure 3 1 is a schematic top view of the three-axis Hall effect magnetic sensor in the second embodiment of the present invention;

[0011] Figure 4 FIG. 1 is a schematic top view of a three-axis Hall magnetic sensor in a third embodiment of the present invention. [Specific implementation method]

[0012] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0013] The "one embodiment" or "embodiment" referred to herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The "in one embodiment" that appears in different places in this specification does not all refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments. In the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", "coupled" and other terms indicating electrical connection should be understood in a broad sense; for example, it can be a direct electrical connection, or it can be indirectly electrically connected through an intermediate medium, and the intermediate medium can be an electronic component, a functional circuit, etc. For ordinary technicians in this field, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0014] The utility model provides a three-axis Hall magnetic sensor, which utilizes horizontal Hall and vertical Hall technologies to form a single Hall sensing structure and has a three-axis magnetic field detection function.

[0015] Figure 1 FIG. 1 is a schematic top view of the three-axis Hall magnetic sensor in the first embodiment of the present invention. Figure 2 for Figure 1 Schematic cross-sectional view of the three-axis Hall magnetic sensor along the section line AA.

[0016] like Figure 1 As shown, the three-axis Hall effect magnetic sensor 100 includes a substrate (not shown) and a doped well formed on the substrate. The doped well can be shaped like a cross, exhibiting both axial and centrosymmetry. The doped well includes a first doped strip 101 extending along a first direction and a second doped strip 102 extending along a second direction perpendicular to the first direction and perpendicularly intersecting the first doped strip 101.

[0017] The three-axis Hall effect magnetic sensor 100 further includes: a first electrode 111 formed at the intersection of the first doped strip 101 and the second doped strip 102; a second electrode 112 and a third electrode 113 formed at least partially within the first doped strip 101 and located on one side of the first electrode 111; a fourth electrode 114 and a fifth electrode 115 formed at least partially within the first doped strip 101 and located on the other side of the first electrode 111; a sixth electrode 116 and a seventh electrode 117 formed at least partially within the second doped strip 102 and located on one side of the first electrode 111; and an eighth electrode 118 and a ninth electrode 119 formed at least partially within the second doped strip 102 and located on the other side of the first electrode 111. The second electrode 112 and the third electrode 113 are spaced apart from each other along a first direction, with the third electrode 113 being closer to the first electrode 111 than the second electrode 112. The fourth electrode 114 and the fifth electrode 115 are spaced apart from each other along the first direction, with the fourth electrode 114 being closer to the first electrode 111 than the fifth electrode 115. The sixth electrode 116 and the seventh electrode 117 are spaced apart along the second direction, and the seventh electrode 117 is closer to the first electrode 111 than the sixth electrode 116. The eighth electrode 118 and the ninth electrode 119 are spaced apart along the second direction, and the eighth electrode 118 is closer to the first electrode 111 than the ninth electrode 119.

[0018] In one embodiment, the distance between the second electrode 112 and the first electrode 111 is equal to the distance between the fifth electrode 115 and the first electrode 111, the distance between the third electrode 113 and the first electrode 111 is equal to the distance between the fourth electrode 114 and the first electrode 111, the distance between the sixth electrode 116 and the first electrode 111 is equal to the distance between the ninth electrode 119 and the first electrode 111, and the distance between the seventh electrode 117 and the first electrode 111 is equal to the distance between the eighth electrode 118 and the first electrode.

[0019] like Figure 1-2 As shown, the first direction and the second direction are parallel to the surface of the substrate, the third direction is perpendicular to the surface of the substrate, the first direction is parallel to the x-axis, the second direction is parallel to the y-axis, and the third direction is parallel to the z-axis.

[0020] When detecting the magnetic field in the x-axis direction, the first electrode 111 is connected to a power source, the sixth electrode 116 and the ninth electrode 119 are grounded, and the seventh electrode 117 and the eighth electrode 118 are signal output electrodes.

[0021] When detecting the magnetic field in the y-axis direction, the first electrode 111 is connected to a power source, the second electrode 112 and the fifth electrode 115 are grounded, and the third electrode 113 and the fourth electrode 114 are signal output electrodes.

[0022] When detecting the magnetic field in the z-axis direction, there are multiple connection methods. For example, a pair of electrodes formed at least partially within the first doped strip 101, located on both sides of the first electrode 111 and at equal distances from the first electrode 111, are connected to a power supply and ground respectively. Then, a pair of electrodes formed at least partially within the second doped strip 102, located on both sides of the first electrode 111 and at equal distances from the first electrode, serve as signal output electrodes. For another example, a pair of electrodes formed at least partially within the second doped strip 102, located on both sides of the first electrode 111 and at equal distances from the first electrode 111, are connected to a power supply and ground respectively. Then, a pair of electrodes formed at least partially within the first doped strip 101, located on both sides of the first electrode 111 and at equal distances from the first electrode, serve as signal output electrodes.

[0023] For greater clarity, when detecting the magnetic field in the z-axis direction, the connection method of each electrode is as follows.

[0024]

[0025] When measuring magnetic fields in different directions, the same electrode may have multiple uses. In this case, a switch can be used to switch between the multiple uses of the same electrode.

[0026] In one embodiment, the doping type of each electrode is the same as the doping type of the doped well, such as Figure 2 As shown, the doping depth of each electrode is less than the doping depth of the doping well, the doping concentration of each electrode is greater than the doping concentration of the doping well, and the doping type of the doping well is opposite to the doping type of the substrate. The substrate is a semiconductor substrate.

[0027] For example, the doping type of the doped well is N-type, the doping type of the substrate is P-type, and the doping type of each electrode is N-type. In this case, the doped well can be fabricated using an N-well process common to each process node, or using a high-voltage process. Each electrode is fabricated using high-concentration, low-depth ion implantation based on the N-well.

[0028] For another example, the doping type of the doped well is P-type doping, the doping type of the substrate is N-type doping, and the doping type of each electrode is P-type doping.

[0029] It can be seen that the three-axis Hall magnetic sensor in the present invention is a single Hall sensing structure, so that the three-axis magnetic field detection function can be realized by using a single Hall structure, which reduces the number of Hall sensing units in the chip and achieves more efficient magnetic field detection.

[0030] In one embodiment, a signal processing circuit is formed on the substrate, and the signal processing circuit is on the same layer as the three-axis Hall magnetic sensor. The three-axis Hall magnetic sensor is manufactured using a general CMOS (Complementary Metal Oxide Semiconductor) process, without the need to introduce additional special processes. The three-axis magnetic sensor is ultimately integrated into a single chip, so that there is no need for multiple chips to achieve the three-axis magnetic field detection function as in the prior art. The three-axis Hall sensor can be used for magnetic field detection in consumer electronics, industry, automobiles and other fields.

[0031] Specifically, first, a standard integrated circuit manufacturing process is used to prepare a substrate such as Figure 1 The three-axis Hall effect magnetic sensor shown here uses a single structure to achieve magnetic detection in three directions. The three-axis Hall effect magnetic sensor and signal processing circuit are located on the same layer. After the three-axis Hall effect magnetic sensor is completed using front-end CMOS, the metal layer and dielectric layer are completed using a common back-end CMOS process.

[0032] like Figure 1 As shown, the length L1 of the second electrode 112, the third electrode 113, the fourth electrode 114, and the fifth electrode 115 along the second direction y is less than the width W1 of the first doped strip 101 along the second direction, and the second electrode 112, the third electrode 113, the fourth electrode 114, and the fifth electrode 115 are completely located within the first doped strip 101.

[0033] The length L2 of the sixth electrode 116, the seventh electrode 117, the eighth electrode 118, and the ninth electrode 119 along the first direction x is less than the width W2 of the second doped strip 102 along the first direction. The sixth electrode 116, the seventh electrode 117, the eighth electrode 118, and the ninth electrode 119 are completely located within the second doped strip 102. The side length of the first electrode 111 along the first direction is less than the width W2 of the second doped strip 102 along the first direction, and the side length of the first electrode 111 along the second direction is less than the width W1 of the first doped strip 102 along the second direction.

[0034] The first electrode 111 may be square, and each electrode may be in the form of a long strip. The length of the first doped strip 101 along the first direction is greater than the width W1 of the first doped strip 101 along the second direction, and the width of the second doped strip 102 along the first direction is less than the length of the second doped strip 102 along the second direction. The length and width of the first doped strip 101 may be equal to the length and width of the second doped strip 102.

[0035] like Figure 3 As shown, the length L1 of the second electrode 112, the third electrode, the fourth electrode, and the fifth electrode along the second direction y is greater than the width W1 of the first doped strip 101 along the second direction. Both ends of each of the second electrode 112, the third electrode, the fourth electrode, and the fifth electrode extend beyond the first doped strip 101. The length L2 of the sixth electrode 116, the seventh electrode, the eighth electrode, and the ninth electrode along the first direction is greater than the width W2 of the second doped strip 102 along the first direction. Both ends of each of the sixth electrode, the seventh electrode, the eighth electrode, and the ninth electrode extend beyond the second doped strip 102. The side length of the first electrode 111 is still less than both the width W2 of the second doped strip 102 along the first direction and the width W1 of the first doped strip 102 along the second direction.

[0036] like Figure 4 As shown, the length L1 of the second electrode 112, the third electrode, the fourth electrode, and the fifth electrode along the second direction y is greater than the width W1 of the first doped strip 101 along the second direction, and the length L2 of the sixth electrode 116, the seventh electrode, the eighth electrode, and the ninth electrode along the first direction is greater than the width W2 of the second doped strip 102 along the first direction. The side length W3 of the first electrode 111 is also greater than the width W2 of the second doped strip 102 along the first direction and the width W1 of the first doped strip 102 along the second direction.

[0037] Of course, in other embodiments, the length L1 of the second electrode 112, the third electrode, the fourth electrode, and the fifth electrode along the second direction y may also be equal to the width W1 of the first doped strip 101 along the second direction, and the length L2 of the sixth electrode 116, the seventh electrode, the eighth electrode, and the ninth electrode along the first direction may also be equal to the width W2 of the second doped strip 102 along the first direction. The side length W3 of the first electrode 111 may also be equal to the width W2 of the second doped strip 102 along the first direction and the width W1 of the first doped strip 102 along the second direction.

[0038] As described above, the width W2 of the second doping strip 102 along the first direction may be equal to or different from the width W1 of the first doping strip 102 along the second direction, and the first electrode 111 may be rectangular instead of square.

[0039] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0040] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify and modify the above embodiments within the scope of the present invention.

Claims

1. A three-axis Hall magnetic sensor, characterized in that: It includes: substrate; A doped well formed on a substrate, wherein the doped well comprises a first doped strip extending along a first direction and a second doped strip extending along a second direction perpendicular to the first direction and perpendicularly intersecting the first doped strip; a first electrode formed at the intersection of the first doped strip and the second doped strip; a second electrode and a third electrode at least partially formed in the first doped strip and located on one side of the first electrode, wherein the second electrode and the third electrode are spaced apart from each other along the first direction, and the third electrode is closer to the first electrode than the second electrode; a fourth electrode and a fifth electrode at least partially formed in the first doped strip and located on the other side of the first electrode, wherein the fourth electrode and the fifth electrode are spaced apart from each other along the first direction, and the fourth electrode is closer to the first electrode than the fifth electrode; a sixth electrode and a seventh electrode at least partially formed in the second doped strip and located on one side of the first electrode, wherein the sixth electrode and the seventh electrode are spaced apart from each other along the second direction, and the seventh electrode is closer to the first electrode than the sixth electrode; An eighth electrode and a ninth electrode are at least partially formed in the second doped strip and are located on the other side of the first electrode, wherein the eighth electrode and the ninth electrode are spaced apart from each other along the second direction, and the eighth electrode is closer to the first electrode than the ninth electrode.

2. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The first direction and the second direction are both parallel to the surface of the substrate, the third direction is perpendicular to the surface of the substrate, the first direction is parallel to the x-axis, the second direction is parallel to the y-axis, and the third direction is parallel to the z-axis. When detecting the magnetic field in the x-axis direction, the first electrode is connected to the power supply, the sixth electrode and the ninth electrode are grounded, and the seventh electrode and the eighth electrode are signal output electrodes; When detecting the magnetic field in the y-axis direction, the first electrode is connected to the power supply, the second electrode and the fifth electrode are grounded, and the third electrode and the fourth electrode are signal output electrodes.

3. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The distance between the second electrode and the first electrode is equal to the distance between the fifth electrode and the first electrode, and the distance between the third electrode and the first electrode is equal to the distance between the fourth electrode and the first electrode. The distance between the sixth electrode and the first electrode is equal to the distance between the ninth electrode and the first electrode, and the distance between the seventh electrode and the first electrode is equal to the distance between the eighth electrode and the first electrode.

4. The three-axis Hall magnetic sensor according to claim 3, characterized in that: The first direction and the second direction are both parallel to the surface of the substrate, the third direction is perpendicular to the surface of the substrate, the first direction is parallel to the x-axis, the second direction is parallel to the y-axis, and the third direction is parallel to the z-axis. When detecting the magnetic field in the z-axis direction, a pair of electrodes at least partially formed in the first doped strip, located on both sides of the first electrode and with an equal distance from the first electrode are connected to a power supply and a ground respectively, and a pair of electrodes at least partially formed in the second doped strip, located on both sides of the first electrode and with an equal distance from the first electrode are respectively used as signal output electrodes; or, a pair of electrodes at least partially formed in the second doped strip, located on both sides of the first electrode and with an equal distance from the first electrode are respectively connected to a power supply and a ground respectively, and a pair of electrodes at least partially formed in the first doped strip, located on both sides of the first electrode and with an equal distance from the first electrode are respectively used as signal output electrodes, When measuring magnetic fields in different directions, if the same electrode has multiple uses, a switch is used to switch the multiple uses of the same electrode.

5. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The doping type of each electrode is the same as the doping type of the doping well, the doping depth of each electrode is less than the doping depth of the doping well, the doping concentration of each electrode is greater than the doping concentration of the doping well, and the doping type of the doping well is opposite to the doping type of the substrate.

6. The three-axis Hall magnetic sensor according to claim 5, characterized in that: The doping type of the doped well is N-type doping, and the doping type of the substrate is P-type doping.

7. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The lengths of the second electrode, the third electrode, the fourth electrode, and the fifth electrode along the second direction are smaller than the width of the first doped strip along the second direction, and the second electrode, the third electrode, the fourth electrode, and the fifth electrode are completely located within the first doped strip; The length of the second electrode, the third electrode, the fourth electrode, and the fifth electrode along the second direction is greater than the width of the first doped strip along the second direction, and both ends of each of the second electrode, the third electrode, the fourth electrode, and the fifth electrode extend beyond the first doped strip; or The length of the second electrode, the third electrode, the fourth electrode and the fifth electrode along the second direction is equal to the width of the first doped strip along the second direction, and each of the second electrode, the third electrode, the fourth electrode and the fifth electrode is exactly located in the first doped strip.

8. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The lengths of the sixth electrode, the seventh electrode, the eighth electrode, and the ninth electrode along the first direction are smaller than the widths of the second doped strips along the first direction, and the sixth electrode, the seventh electrode, the eighth electrode, and the ninth electrode are completely located within the second doped strips; The length of the sixth electrode, the seventh electrode, the eighth electrode, and the ninth electrode along the first direction is greater than the width of the second doped strip along the first direction, and both ends of each of the sixth electrode, the seventh electrode, the eighth electrode, and the ninth electrode extend beyond the second doped strip; or The length of the sixth electrode, the seventh electrode, the eighth electrode and the ninth electrode along the first direction is equal to the width of the second doped strip along the first direction, and each of the sixth electrode, the seventh electrode, the eighth electrode and the ninth electrode is exactly located in the second doped strip.

9. The three-axis Hall magnetic sensor according to claim 1, characterized in that: The side length of the first electrode along the first direction is smaller than the width of the second doped strip along the first direction, and the side length of the first electrode along the second direction is smaller than the width of the first doped strip along the second direction; or, The side length of the first electrode along the first direction is greater than or equal to the width of the second doped strip along the first direction, and the side length of the first electrode along the second direction is greater than or equal to the width of the first doped strip along the second direction.

10. The three-axis Hall magnetic sensor according to claim 1, characterized in that: A signal processing circuit is formed on the substrate, and the signal processing circuit and the three-axis Hall magnetic sensor are on the same layer. The three-axis Hall magnetic sensor is manufactured using CMOS technology. The three-axis Hall magnetic sensor is a single chip.

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