Sensor with magnetic shield

Abstract

A magnetic sensor (70) is disclosed. The magnetic sensor can include a sensing element (10) and a magnetic shield (72). The sensing element and the magnetic shield can be vertically stacked with respect to each other. The magnetic shield can be a magnetic shield plate that includes ferromagnetic portions laterally separated by a non-ferromagnetic material. The sensing element can have a first side and a second side opposite the first side. The magnetic shield can be vertically stacked on the first side of the sensing element. The magnetic shield can be separated from the sensing element by an isolation layer (76). A passivation layer (78) can cover at least a portion of the sensing element or the magnetic shield. The sensing element can be configured to sense a magnetic field property of a magnetic field source located on the second side of the sensing element.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 901956, filed September 18, 2019, entitled “Sensors with Magnetic Shielding,” the entire disclosure of which is incorporated herein by reference for all purposes. Furthermore, any and all applications that identify foreign or domestic priority claims in the Application Data Sheet filed with this application pursuant to 37 CFR 1.57 are incorporated by reference. Technical Field

[0003] This application relates to sensors, and more specifically, to multi-turn sensors, such as giant magnetoresistive multi-turn sensors with magnetic shielding. Background Technology

[0004] Magnetic sensors can sense magnetic field characteristics, such as the direction of the magnetic field. An example of a magnetic sensor is a multi-turn counter. A multi-turn counter can record the number of times a device or its components rotate. Electromagnetic multi-turn sensors can include electrical multi-turn sensors, magnetic multi-turn sensors, and multi-turn sensors that use both electrical and magnetic principles. Examples of electromagnetic multi-turn sensors include giant magnetoresistance (GMR) sensors and tunnel magnetoresistance (TMR) sensors.

[0005] Multi-turn counters have a variety of applications. An electronic implementation of a multi-turn counter can convert physical position or motion into an electromagnetic representation suitable for processing. For example, a drive-by-wire car can use a multi-turn counter to track the number of times the steering wheel is turned. This allows the vehicle control system to distinguish whether the steering wheel is at 45 degrees or 405 degrees, even though the steering wheel is in the same position at both angles. Summary of the Invention

[0006] To summarize the invention, certain aspects, advantages, and novel features of the innovation are described herein. It should be understood that not all such advantages can necessarily be achieved according to any particular embodiment. Therefore, the innovation described herein may be embodied or implemented in a manner that realizes or optimizes one or more advantages taught herein, without necessarily realizing other advantages taught or suggested herein.

[0007] In one aspect, a magnetic sensor is disclosed. The magnetic sensor may include a magnetic shielding plate having ferromagnetic portions laterally spaced from each other by a non-ferromagnetic material. The magnetic shielding plate is configured to shield a portion of a magnetic field, thereby allowing the unshielded portion of the magnetic field to pass through. The magnetic sensor may also include magnetic field sensing elements vertically stacked on the magnetic shielding plate. The magnetic field sensing elements are configured to sense the magnetic field characteristics of the unshielded magnetic field.

[0008] In one embodiment, the ferromagnetic portion comprises ferromagnetic particles. The ferromagnetic particles may be mixed into the non-ferromagnetic material.

[0009] In one embodiment, the ferromagnetic portion is patterned such that the ferromagnetic portion is equally spaced apart by the non-ferromagnetic material.

[0010] In one embodiment, the ferromagnetic portion comprises ferromagnetic rings of different sizes.

[0011] In one embodiment, the ferromagnetic portion includes a rectangular shielding element, a circular shielding element, or a hexagonal shielding element.

[0012] In one embodiment, the magnetic sensor further includes a passivation layer configured to protect the magnetic shielding plate or magnetic field sensing element.

[0013] In one embodiment, the magnetic shielding plate is configured to shield a portion of the magnetic field of the magnet. The magnetic field sensing element may be located between the magnet and the magnetic shielding plate.

[0014] In one embodiment, the magnetic shielding plate is configured to shield a portion of the magnetic field of the magnet. The magnetic shielding plate may be located between the magnet and the magnetic field sensing element.

[0015] In one embodiment, the magnetic shielding plate and the magnetic field sensing element are formed on a wafer.

[0016] In one implementation, the magnetic sensor is a multi-turn sensor.

[0017] In one implementation, the magnetic sensor is a giant magnetoresistive sensor.

[0018] In one aspect, a magnetic sensor is disclosed. The magnetic sensor may include a sensing element having a first side and a second side opposite to the first side. The magnetic sensor may also include a magnetic shield vertically stacked on the first side of the sensing element. The magnetic shield is spaced apart from the sensing element by an insulating layer. The magnetic sensor may also include a passivation layer covering at least a portion of the sensing element or the magnetic shield. The sensing element is configured to sense the magnetic field characteristics of a magnetic field source located below the second side of the sensing element.

[0019] In one embodiment, the magnetic field characteristics include the magnetic field direction of the magnetic field source.

[0020] In one embodiment, the magnetic shielding includes ferromagnetic portions laterally spaced by a non-ferromagnetic material. The ferromagnetic portions may include ferromagnetic particles, and the ferromagnetic particles may be mixed into the non-ferromagnetic material. The ferromagnetic portions may be patterned such that they are equally spaced by the non-ferromagnetic material.

[0021] In one embodiment, the sensing element and the magnetic field source are at least partially separated by air.

[0022] In one aspect, a magnetic sensor is disclosed. The magnetic sensor may include a sensing element configured to sense magnetic field characteristics of a magnetic field from a magnetic field source. The magnetic sensor may also include a magnetic field shielding member configured to shield a portion of the magnetic field from the magnetic field source. The magnetic sensor may further include a passivation layer covering at least a portion of the sensing element or the magnetic field shielding member.

[0023] In one embodiment, the magnetic sensor is a multi-turn sensor. The magnetic field characteristics may include the direction of the magnetic field, and the magnetic field source may include a magnet.

[0024] In one embodiment, the magnetic field shielding member includes ferromagnetic portions laterally spaced by non-ferromagnetic material.

[0025] In one embodiment, the magnetic field shielding member includes an arrangement of sensing elements relative to the magnetic shield and the magnetic field source, the arrangement including sensing elements located between the magnetic shield and the magnetic field source. Attached Figure Description

[0026] Figure 1A This is a schematic diagram of a magnetic field sensing system according to one embodiment, showing the arrangement of the sensing element and magnetic shield relative to the magnetic field source.

[0027] Figure 1B This is a schematic diagram of a magnetic field sensing system according to another embodiment, showing the arrangement of the sensing element and magnetic shield relative to the magnetic field source.

[0028] Figure 2 The illustration shows the arrangement of the ferromagnetic portion of a magnetic shield according to one embodiment.

[0029] Figure 3 The illustration shows the arrangement of the ferromagnetic portion of a magnetic shield according to another embodiment.

[0030] Figure 4 The illustration shows the arrangement of the ferromagnetic portion of a magnetic shield according to another embodiment.

[0031] Figure 5 The illustration shows the arrangement of the ferromagnetic portion of a magnetic shield according to another embodiment.

[0032] Figure 6 This is a schematic cross-sectional view of magnetic shielding according to one embodiment.

[0033] Figure 7 This is a schematic cross-sectional view of a sensor according to one embodiment.

[0034] Figure 8 This is a schematic cross-sectional view of a sensor according to another embodiment.

[0035] Figure 9A multi-turn counter system according to one embodiment is shown. Detailed Implementation

[0036] The following detailed description of certain embodiments presents various descriptions of particular embodiments. However, the innovations described herein can be embodied in a variety of different ways, such as those defined and covered by the claims. Reference is made in this specification to the accompanying drawings, wherein similar reference numerals may denote the same or functionally similar elements. It should be understood that the elements shown in the figures are not necessarily drawn to scale. Furthermore, it should be understood that some embodiments may include more elements and / or a subset of the elements shown in the figures than are shown. Additionally, some embodiments may combine any suitable combination of features from two or more figures.

[0037] Magnetic sensors can include multi-turn sensors (e.g., giant magnetoresistive (GMR) sensors, tunneling magnetoresistive (TMR) sensors, or any xMR sensor). To ensure accurate measurements, such as accurate rotation counts, the magnetic field strength (H) of the sensor element included in the magnetic sensor is preferably within a magnetic field window. The magnetic field window can be defined by a range of magnetic field strengths between a minimum magnetic field strength (Hmin) and a maximum magnetic field strength (Hmax) to which the sensing element is configured to process.

[0038] Magnetic sensors can include magnetic strips. These strips can be giant magnetoresistive tracks physically arranged in a helical pattern. Based on the material and cross-sectional dimensions of the strip, it can exhibit magnetic anisotropy, such as high anisotropy. The strip can store magnetic energy. For example, the magnetic field window can be controlled by varying the strip width. Typically, a narrower strip width will provide a higher magnetic field window. However, forming magnetic strips with relatively narrow strip widths (e.g., 150 nm to 1000 nm) can be challenging. When using photolithography to form such relatively narrow strips, the yield of the magnetic sensor may be reduced, for example, due to edge roughness.

[0039] To provide a magnetic sensor with a relatively high magnetic field window while having a moderately wide stripe width, or to avoid a relatively narrow stripe width, magnetic shielding can be implemented. Magnetic shielding can short-circuit a portion of the magnetic field. However, the effectiveness of magnetic shielding can be difficult to control. For example, shielding (e.g., iron shielding, nickel shielding, cobalt shielding, etc.) may saturate at a certain magnetic field strength. For example, when the shielding and sensing element are closely positioned, the magnetic field that would otherwise be applied to the sensing element may be shielded too strongly.

[0040] The various embodiments disclosed herein relate to magnetic sensors including magnetic shielding. The magnetic shielding may include ferromagnetic portions separated by a non-ferromagnetic material. In some embodiments, the sensing element may be disposed between the magnetic shielding and a magnet or magnetic field source. By effectively shielding the magnetic field, the various embodiments disclosed herein can provide a magnetic sensor that offers a relatively high magnetic field window while having a wider magnetic stripe than a sensor with magnetic shielding that does not provide a similar magnetic field window.

[0041] Figure 1A This is a schematic diagram of a magnetic field sensing system 1, showing the arrangement of a sensing element 10 and a magnetic shield 12 relative to a magnetic field source (e.g., a magnet 14) according to one embodiment. Figure 1A The magnetic shield 12 shown includes ferromagnetic portions separated from each other by non-ferromagnetic portions. Reference will be made below. Figure 2-6 Various embodiments of the magnetic shield 12 are explained. In some embodiments, as shown herein, the lateral dimension of the magnetic shield 12 may be larger than the lateral dimension of the sensing element 10. In some embodiments, the lateral dimension of the magnetic shield 12 may be at least twice the lateral dimension of the sensing element 10.

[0042] Sensing element 10 may include any suitable type of magnetic sensing element. In some embodiments, sensing element 10 and magnetic shield 12 together may define a magnetic sensor. The magnetic sensor may include, for example, a multi-turn sensor (e.g., a giant magnetoresistive (GMR) sensor, a tunnel magnetoresistive (TMR) sensor, or any xMR sensor). In some embodiments, a multi-turn sensor may include a domain wall generator coupled to one end of a magnetic strip in sensing element 10.

[0043] Sensing element 10 can sense various magnetic properties of a magnetic field. For example, sensing element 10 can sense the direction of the magnetic field of magnet 14. Magnet 14 is shown as a magnetic field source. However, a magnetic field source can be anything that generates a magnetic field.

[0044] like Figure 1A As shown, a magnetic shield 12 can be positioned between the sensing element and the magnet 14. The magnetic shield 12 may include soft magnetic elements. The magnetic shield 12 can short-circuit a portion of the magnetic field. In the illustrated arrangement, the magnetic shield 12 may bypass certain magnetic field lines. Therefore, at least a portion of the magnetic field generated by the magnet 14 is shielded by the magnetic shield 12.

[0045] Figure 1B This is a schematic diagram of a magnetic field sensing system 2, showing the arrangement of the sensing element 10 and the magnetic shield 16 relative to a magnetic field source (e.g., a magnet 14) according to one embodiment. Similar to... Figure 1A The magnetic shield 12 shown may include ferromagnetic portions spaced apart from each other by non-ferromagnetic portions. However, in some embodiments, the magnetic shield 16 may consist only of ferromagnetic material.

[0046] exist Figure 1B In the middle, the sensing element 10 is located between the magnet 14 and the magnetic shield 16. Figure 1B The image shows the sensing element 10 centered on the magnetic shield 16. However, in some embodiments, the sensing element 10 and the magnetic shield 16 may be laterally offset. In some embodiments, the lateral dimension of the magnetic shield 16 may be larger than the lateral dimension of the sensing element 10. In some embodiments, the lateral dimension of the magnetic shield 16 may be at least twice the lateral dimension of the sensing element 10.

[0047] In some embodiments, the magnetic shield 16 can shield or block at least a portion (e.g., a shielded portion) of the magnetic field. In other words, the magnetic shield 16 is arranged such that a portion (the shielded portion) of the magnetic field is shielded. For example, the shielded portion of the magnetic field may include less than 100% of the magnetic field, such as 80%. Therefore, the magnetic shield 16 can shield at least a portion of the magnetic field while allowing other portions (e.g., unshielded portions) of the magnetic field to pass through. For example, the shielding effect of the magnetic shield 16 can be controlled by selecting the distance between the sensing element 10 and the magnetic shield 16. In some embodiments, the closer the distance between the sensing element 10 and the magnetic shield 16, the better the shielding effect of the magnetic shield 16. In some applications, the distance between the sensing element 10 and the magnetic shield 16 may be in the range of 1 μm to 1 mm, for example. In some applications, the distance between the magnet 14 and the sensing element 10 may be in the range of 1 mm to 30 mm, for example.

[0048] Figure 2-5 Magnetic shielding according to various embodiments is shown (e.g., Figure 1A and 1B The arrangement or pattern of the ferromagnetic portions of the magnetic shields 12, 16 shown. In some embodiments, Figure 1A and 1B The magnetic shields 12 and 16 shown may include, for example: Figure 2-6 The ferromagnetic portion is arranged as shown.

[0049] Figure 2This is a schematic perspective view of the ferromagnetic portion of a magnetic shield according to one embodiment. The ferromagnetic portion may include a first ring portion 20a, a second ring portion 20b, and a third ring portion 20c. The first ring portion 20a and the second ring portion 20b may be spaced apart by a gap 22a. The second ring portion 20b and the third ring portion 20c may be spaced apart by the gap 22b. The third ring portion 20c may include a hole 24 in the middle. Non-ferromagnetic material may be disposed in the gaps 22a, 22b and / or the hole 24. The magnetic shielding using the ferromagnetic portions 20a, 20b, and 20c can shield at least a portion of the magnetic field. The portions 20a, 20b, and 20c can provide uniform or near-uniform shielding on the surface of the magnetic shield. This can be attributed at least in part to the circular or circular integral shape of the ferromagnetic portions 20a, 20b, and 20c.

[0050] Figure 3 This is a schematic perspective view of the ferromagnetic portion 30 of a magnetically shielded structure according to one embodiment. Figure 3 Each ferromagnetic portion 30 shown can be separated by a gap 32. Non-ferromagnetic material can be disposed in the gap 32. Figure 3 Each ferromagnetic portion 30 shown comprises a square. However, as Figure 4 and 5 As shown, the ferromagnetic portion can include any other shape. (and) Figure 2 Similarly, the magnetic shielding of the ferromagnetic portion 30 can shield at least a portion of the magnetic field. The ferromagnetic portion 30 can provide uniform or near-uniform shielding on the surface of the magnetic shield. This can be attributed at least in part to the circular or circular overall shape of the ferromagnetic portion 30.

[0051] Figure 4 This is a schematic perspective view of the ferromagnetic portion 40 of a magnetically shielded structure according to one embodiment. Figure 4 Each ferromagnetic portion 40 shown can be separated by a gap 42. Non-ferromagnetic material can be disposed in the gap 42. Figure 4 Each ferromagnetic portion 40 shown includes a circle or a circular shape. However, as... Figure 3 and 5 As shown, the ferromagnetic portion can include any other shape. (and) Figure 2 and 3 Similarly, the magnetic shielding of the ferromagnetic portion 40 can shield at least a portion of the magnetic field. The ferromagnetic portion 40 can provide uniform or near-uniform shielding on the surface of the magnetic shield. This can be attributed at least in part to the circular or circular overall shape of the ferromagnetic portion 40.

[0052] Figure 5 This is a schematic perspective view of the ferromagnetic portion 50 of a magnetically shielded structure according to one embodiment. Figure 5 Each ferromagnetic portion 50 shown can be separated by a gap 52. Non-ferromagnetic material can be disposed in the gap 52. Figure 5Each ferromagnetic portion 50 shown includes a hexagonal shape. However, as Figure 3 and 4 As shown, the ferromagnetic portion can include any other shape. (and) Figure 2 , 3 Similar to 4, the magnetic shielding of the ferromagnetic portion 50 can shield at least a portion of the magnetic field. The ferromagnetic portion 50 can provide uniform or near-uniform shielding on the surface of the magnetic shield. This can be attributed at least in part to the circular or circular overall shape of the ferromagnetic portion 50.

[0053] Magnetic shielding according to various embodiments may include ferromagnetic portions comprising different shapes and different gaps between them. The selection of the size of the ferromagnetic portions, the gap size, the shape of the ferromagnetic portions, and / or the arrangement of the ferromagnetic portions can advantageously control the shielding effect of the magnetic shield. In some embodiments, the ferromagnetic portions are equally spaced apart. In other embodiments, the gap / spacing between the ferromagnetic portions may vary.

[0054] use Figure 2-5 The magnetic shielding with the ferromagnetic portions shown can be formed using wafer-level processes. For example, patterned magnetic shielding portions (e.g., ferromagnetic portions) can be formed on a substrate. The substrate (e.g., a wafer) with the ferromagnetic portions can be diced to define multiple magnetic shields.

[0055] Figure 6 This is a schematic cross-sectional view of a magnetic shield 60 according to one embodiment. In some embodiments, Figure 1A and 1B The magnetic shields 12 and 16 shown may include a magnetic shield 60. The magnetic shield 60 may include a compound of ferromagnetic and non-ferromagnetic materials. For example, the magnetic shield may include a ferromagnetic portion 62 (e.g., ferromagnetic powder or particles) mixed in a non-ferromagnetic material 64.

[0056] In some embodiments, the amount of ferromagnetic material in the magnetic shield 60 can control the saturation point and / or permeability of the magnetic shield 60. For example, in some embodiments, the amount of ferromagnetic material in the magnetic shield 60 can be selected such that the permeability of the magnetic shield 60 is in the range of 2 to 100. In various embodiments, the magnetic shield 60 may have, for example... Figure 2-5 The arrangement or pattern shown.

[0057] The non-ferromagnetic portion 64 may comprise any other suitable non-ferromagnetic material. For example, in some embodiments, the non-ferromagnetic portion 64 may comprise plastic. In some embodiments, the width w of the magnetic shield 60 may be greater than the thickness t of the magnetic shield 60. In some embodiments, the magnetic shield 60 may comprise a magnetic shielding plate or disk.

[0058] Figure 7This is a schematic cross-sectional view of a sensor 70 according to one embodiment. The sensor 70 may include a sensing element 10, a magnetic shield 72 separated by an isolation layer 76, a substrate 74 (e.g., a wafer) supporting the sensing element 10 and the magnetic shield 72, and a passivation layer 78 above the sensing element 10. As shown, the sensing element 10 and the magnetic shield 72 are stacked vertically.

[0059] The magnetic shield 72 may include any embodiment of the magnetic shielding disclosed herein. In some embodiments, the magnetic shield 72 may be formed directly over the substrate 74. In other embodiments, the sensor 70 may be included as an intermediate layer between the substrate 74 and the magnetic shield 72.

[0060] The substrate 74 may include any suitable material that provides support for the sensing element 10 and the magnetic shield 72. For example, the substrate 74 may include silicon (Si).

[0061] The isolation layer 76 may include non-ferromagnetic and / or non-conductive materials. The isolation layer 76 may include, for example, silicon nitride (Si3N4), aluminum oxide (Al2O3), polyimide, and / or similar materials.

[0062] The passivation layer 78 may include a non-ferromagnetic and / or non-conductive material. The passivation layer 78 may include, for example, silicon nitride (Si3N4), aluminum oxide (Al2O3), polyimide, and / or similar materials.

[0063] In some implementations, sensor 70 can be fabricated using a wafer-level process. Figure 7 The method for providing the sensor 70 shown may include providing a substrate 74. The method may also include forming a magnetic shield 72. The magnetic shield 72 may be formed, for example, by depositing at least one ferromagnetic material on the substrate 74. In some embodiments, the magnetic shield 72 may be patterned or arranged using a photolithography process. In such embodiments, for example, a photoresist layer may be applied to the ferromagnetic material. The method may also include disposing an isolation layer 76 on the magnetic shield 72. The method may include forming a sensing element 10 on the isolation layer 76. The method may also include disposing a passivation layer 78 on the sensing element 10.

[0064] In some embodiments, the width w of the magnetic shield 72 may be greater than the thickness t of the magnetic shield 72. The ferromagnetic portions of the magnetic shield 72 may be arranged on a plane. For example, the ferromagnetic portions of the magnetic shield 72 may be arranged on the surface of the substrate 74. In such embodiments, the magnetic shield 72 may include ferromagnetic portions laterally spaced by non-ferromagnetic material, thereby defining a magnetic shielding plate or disk.

[0065] Figure 8This is a schematic cross-sectional view of a sensor 80 according to one embodiment. The sensor 80 may include a sensing element 10, a magnetic shield 72 separated by an isolation layer 76, a substrate 74 (e.g., a wafer) supporting the sensing element 10 and the magnetic shield 72, and a passivation layer 78 located on the magnetic shield 72. As shown, the sensing element 10 and the magnetic shield 72 are stacked vertically.

[0066] In some embodiments, the sensing element 10 may be formed directly on top of the substrate 74. In other embodiments, the sensor 70 may be included in an intermediate layer between the substrate 74 and the sensing element 10.

[0067] In some implementations, sensor 80 can be fabricated using a wafer-level process. Figure 8 The method of providing the sensor 80 shown may include providing a substrate 74. The method may also include forming a sensing element 10. The method may further include disposing an isolation layer 76 over the sensing element 10. The method may include forming a magnetic shield 72 over the isolation layer 76. The magnetic shield 72 may be formed, for example, by depositing at least one ferromagnetic material on the substrate 74. In some embodiments, the magnetic shield 72 may be patterned or arranged using a photolithography process. In such embodiments, for example, a photoresist layer may be applied to the ferromagnetic material. The method may also include disposing a passivation layer 78 on the magnetic shield 72.

[0068] In some embodiments, the width w of the magnetic shield 72 may be greater than the thickness t of the magnetic shield 72. The ferromagnetic portions of the magnetic shield 72 may be arranged on a plane. For example, the ferromagnetic portions of the magnetic shield 72 may be arranged on the surface of the isolation layer 76. In such embodiments, the magnetic shield 72 may include ferromagnetic portions laterally spaced by non-ferromagnetic material, thereby defining a magnetic shielding plate or disk.

[0069] Figure 9 An example multi-turn counter system 90 according to an embodiment is shown. The system 90 may include a rotatable object 92, shafts 94 and 96, gear 98, one or more magnets 100, a magnetic field (B) 102, a domain wall generator (DWG) 104, a magnetically shielded sensing element 106, a drive circuit 108, a control circuit 110, a sensing circuit 112, an angle sensor system 114, and a computing device 116 including a CPU or decoder 118, a memory 120, and an output port 122.

[0070] Rotatable objects such as knobs, steering wheels, levers, handles, propellers, wheels, balls, etc., can be connected to magnet 100. One or more shafts 94, 96 and gears 98 can be used to multiply the number of times magnet 100 rotates per revolution of object 92. Although Figure 9A shaft and gear are shown, but it should be understood that in some embodiments neither a shaft nor a gear is included. Magnet 100 generates a magnetic field 102 and orients the magnetic field 102 in different directions based on the orientation of the magnet. Changing the magnetic field 102 can cause domain wall generator 104 to propagate domain walls through a magnetic strip included in sensing element 106, which may be physically arranged in a helical shape. Measurements from sensing circuitry 112 can be provided (e.g., transmitted) to computing device 116. The measurements can be stored in memory 120, and a CPU or decoder 118 can convert the measurements into a decoded output, which may be a digital output, output via output port 122, or used within the computing device (e.g., within CPU 118). System 90 may include an angle sensor system 114. The angle sensor system can detect the angular position of a rotating object 92, but may lack the ability to count rotations (e.g., cannot distinguish between zero degrees and 360 degrees). For example, the angle sensor may be a single-turn or half-turn angle sensor. Angle sensors can be based on anisotropic magnetoresistive, tunneling magnetoresistive, GMR, Hall effect, or other techniques. The decoded output can be used in conjunction with angle sensor system 114 to accurately determine the cumulative rotation angle of object 92. The sensing element with magnetic shielding 106 can include any sensing element and magnetic shielding disclosed herein.

[0071] In the above embodiments, devices, systems, and methods for multi-turn sensors have been described in conjunction with specific embodiments. However, it should be understood that the principles and advantages of the embodiments can be used in any other system, apparatus, or method that can benefit from multi-turn magnetic sensors.

[0072] The principles and advantages described herein can be implemented in a variety of devices. Examples of such devices may include, but are not limited to, vehicles, motors, treadmills, flywheels, GPS systems, doors, population counters, consumer electronics, components of consumer electronics, electronic testing equipment, etc. Consumer electronics may include, but are not limited to, wireless devices, mobile phones (e.g., smartphones), healthcare monitoring equipment, in-vehicle electronic systems such as automotive electronic systems, computers, handheld computers, tablets, laptops, personal digital assistants (PDAs), microwave ovens, refrigerators, stereo systems, cassette recorders or players, DVD players, CD players, digital video recorders (DVRs), VCRs, radios, camcorders, cameras, digital cameras, washing machines, dryers, washer / dryer units, copiers, fax machines, scanners, multifunction peripherals, watches, clocks, etc. Other devices include any device with movable or rotatable parts in which the amount of movement is measured. Furthermore, devices may include unfinished products.

[0073] Unless the context explicitly requires otherwise, throughout the specification and claims, the words “comprising,” “including,” “containing,” “having,” etc., shall be interpreted as inclusive, not exclusive or exhaustive; that is, the word shall be understood as “including but not limited to.” As generally used herein, the words “coupled” or “connected” refer to two or more elements that can be directly connected or connected via one or more intermediate elements. Furthermore, the words “here,” “above,” “below,” and similar meanings, when used in this application, shall refer to the entire application and not any particular part of it. Where the context permits, singular or plural words used in the detailed description may also include the plural or singular, respectively. When referring to a list of two or more items, the word “or” is intended to cover all of the following interpretations: any item in the list, all items in the list, and any combination of items in the list. All numerical values ​​provided herein are intended to include similar values ​​within measurement error.

[0074] Furthermore, unless otherwise expressly stated, the conditional language used herein, such as “may,” “possibly,” “for example,” or otherwise understood in the context in which they are used, is generally intended to convey that certain embodiments include certain features, elements, and / or states, while other embodiments do not.

[0075] The teachings of this invention provided herein can be applied to other systems, not necessarily those described above. Elements and actions of the various embodiments described above can be combined to provide further embodiments.

[0076] Although certain embodiments of the invention have been described, these embodiments are presented by way of example only and are not intended to limit the scope of this disclosure. In fact, the novel methods and systems described herein can be embodied in many other forms. Furthermore, various omissions, substitutions, and changes can be made to the form of the methods and systems described herein without departing from the spirit of this disclosure. The appended claims and their equivalents are intended to cover such forms or modifications that fall within the scope and spirit of this disclosure. Therefore, the scope of the invention is defined by reference to the claims.

Claims

1. A magnetic sensor, comprising: A magnetic shielding plate having ferromagnetic portions that are laterally separated from each other by non-ferromagnetic materials; and The magnetic field sensing elements are stacked vertically on the magnetic shielding plate relative to the magnetic shielding plate. The magnetic shielding plate is configured to shield a portion of the magnetic field, allowing the unshielded portion of the magnetic field to pass perpendicularly to the magnetic shielding plate. The magnetic field sensing element is configured to sense the magnetic field characteristics of the unshielded magnetic field.

2. The magnetic sensor according to claim 1, wherein the ferromagnetic portion comprises ferromagnetic particles, the ferromagnetic particles being mixed in the non-ferromagnetic material.

3. The magnetic sensor according to claim 1, wherein the ferromagnetic portion is patterned such that the ferromagnetic portion is equally spaced apart by the non-ferromagnetic material.

4. The magnetic sensor according to claim 1, wherein the ferromagnetic portion comprises ferromagnetic rings of different sizes.

5. The magnetic sensor according to claim 1, wherein the ferromagnetic portion comprises a rectangular shielding element, a circular shielding element, or a hexagonal shielding element.

6. The magnetic sensor according to claim 1 further includes a passivation layer configured to protect the magnetic shielding plate or the magnetic field sensing element.

7. The magnetic sensor of claim 1, wherein the magnetic shielding plate is configured to shield part of the magnetic field of the magnet, and the magnetic field sensing element is located between the magnet and the magnetic shielding plate.

8. The magnetic sensor of claim 1, wherein the magnetic shielding plate is configured to shield a portion of the magnetic field of the magnet, and the magnetic shielding plate is located between the magnet and the magnetic field sensing element.

9. The magnetic sensor according to claim 1, wherein the magnetic shielding plate and the magnetic field sensing element are formed on a wafer.

10. The magnetic sensor according to claim 1 is a multi-turn sensor.

11. The magnetic sensor according to claim 10 is a giant magnetoresistive sensor.

12. A magnetic sensor, comprising: The sensing element on the chip has a first side and a second side opposite to the first side; A magnetic shield is stacked vertically on the first side of the sensing element relative to the first side of the sensing element, and the magnetic shield is separated from the sensing element by an isolation layer; and A passivation layer covering at least a portion of the sensing element or magnetic shielding. The magnetic shielding is configured to shield a portion of the magnetic field from a magnetic field source located below the second side of the sensing element, allowing the unshielded portion of the magnetic field to pass perpendicularly through the magnetic shielding. The sensing element is configured to sense the magnetic field characteristics of the unshielded magnetic field.

13. The magnetic sensor according to claim 12, wherein the magnetic field characteristics include the magnetic field direction of the magnetic field source.

14. The magnetic sensor of claim 12, wherein the magnetic shield comprises ferromagnetic portions laterally spaced from each other by non-ferromagnetic materials.

15. The magnetic sensor according to claim 14, wherein the ferromagnetic portion comprises ferromagnetic particles, the ferromagnetic particles being mixed in the non-ferromagnetic material.

16. The magnetic sensor of claim 14, wherein the ferromagnetic portion is patterned such that the ferromagnetic portion is equally spaced apart by the nonferromagnetic material.

17. The magnetic sensor of claim 12, wherein the sensing element and the magnetic field source are at least partially separated by air.

18. The magnetic sensor of claim 12, wherein the magnetic field shielding member includes an arrangement of sensing elements relative to the magnetic shield and the magnetic field source, the arrangement including sensing elements located between the magnetic shield and the magnetic field source.

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