Flux concentrators for in-plane magnetic field concentration.

Abstract

The structure (100) includes a substrate (110) having a surface. The structure (100) also includes a horizontal Hall sensor (120) disposed within the substrate (110) and below the surface of the substrate (110). The structure (100) further includes a patterned magnetic concentrator (130) disposed over the surface of the substrate (110), and a protective overcoat layer (140) disposed over the magnetic concentrator (130).

Description

[Technical field]

[0001] Two-dimensional (2D) speed and direction sensors use both horizontal and vertical Hall sensors. Hall sensors are used to measure the magnitude of a magnetic field. Its output voltage is directly proportional to the magnetic field strength passing through it. Hall sensors can be used for proximity sensing, positioning, speed detection, and current sensing applications. 2D pulse encoders also use horizontal Hall sensors, but with sensitivity-enhanced magnetic concentrators formed via package-level deposition, such as pick-and-place of magnetic concentrator disks. Pick-and-place methods have magnetic concentrator disks formed separately from the wafer processing, which then need to be picked up from a separate location, transferred to the wafer, and finally deposited on the wafer, thus hindering the ability of magnetic concentrator patterning. Furthermore, the package-level magnetic concentrator deposition methods used increase the separation distance between the Hall sensor and the magnetic concentrator, reducing the magnetic field strength near the Hall sensor. Also, package-level deposition of the magnetic concentrators increases the overall cost. Summary of the Invention

[0002] In at least one example, a structure includes a substrate including a surface, the structure also includes a horizontal Hall sensor disposed within the substrate and below the surface of the substrate, the structure further includes a patterned magnetic concentrator disposed above the surface of the substrate, and a protective overcoat layer disposed above the magnetic concentrator.

[0003] In another example, a method of forming a structure includes forming a substrate including a surface, disposing a horizontal Hall sensor in the substrate and below the surface of the substrate, forming a magnetic concentrator on the surface of the substrate, and forming a protective overcoat layer on the magnetic concentrator.

[0004] In yet another example, a method includes applying a substantially horizontal magnetic field to a patterned magnetic concentrator, the patterned magnetic concentrator converting the substantially horizontal magnetic field into a substantially vertical magnetic field. The patterned magnetic concentrator is disposed below a protective overcoat layer and above a surface of a substrate. The substantially vertical magnetic field is applied to two horizontal Hall sensors disposed in the substrate and below the surface of the substrate. The method further includes sensing the substantially vertical magnetic field with the two horizontal Hall sensors.

[0005] For a detailed description of various examples, reference will now be made to the accompanying drawings. [Brief description of the drawings]

[0006] [Figure 1] 1 is a cross-sectional schematic side view of a structure including a substrate, a Hall sensor, a magnetic concentrator, and a protective overcoat layer.

[0007] [Diagram 2] 1 is a cross-sectional schematic side view of a structure including a substrate, a Hall sensor, an interlevel dielectric oxide layer, an optional stress compensation layer (e.g., SiN), a magnetic concentrator, and a protective overcoat layer.

[0008] [Diagram 3] 1 is a top view of a structure including a cross-shaped magnetic concentrator with a magnetic field input applied in the horizontal (X) direction, the protective overcoat layer not shown.

[0009] [Figure 4] 1 is a top view of a structure including a cross-shaped magnetic concentrator with a magnetic field input applied in diagonal (xy) directions, the protective overcoat layer not shown.

[0010] [Figure 5A] 1 is a top view of a structure including an elliptical magnetic concentrator, without the protective overcoat layer shown. [Figure 5B]FIG. 5B is a top view of the structure shown in FIG. 5A, illustrating the xy position of the Hall sensors within the structure, with the Hall sensors superimposed.

[0011] [Figure 6A] 1 is a top view of a structure including a wedge-shaped magnetic concentrator, without the protective overcoat layer shown. [Figure 6B] FIG. 6B is a top view of the structure shown in FIG. 6A illustrating the xy position of the Hall sensors within the structure with the Hall sensors superimposed.

[0012] [Figure 7A] 1 is a top view of a structure including a circular magnetic concentrator, without the protective overcoat layer shown. [Figure 7B] FIG. 7B is a top view of the structure shown in FIG. 7A with the Hall sensors superimposed, showing the xy position of the Hall sensors within the structure.

[0013] [Figure 8A] 1 is a top view of a structure including a cross-shaped magnetic concentrator, without the protective overcoat layer shown. [Figure 8B] FIG. 8B is a top view of the structure shown in FIG. 8A, illustrating the xy position of the Hall sensors within the structure, with the Hall sensors superimposed.

[0014] [Figure 9A] 1 is a top view of a structure including an "X" shaped magnetic concentrator, without the protective overcoat layer shown. [Figure 9B] FIG. 9B is a top view of the structure shown in FIG. 9A, illustrating the xy position of the Hall sensors within the structure, with the Hall sensors superimposed.

[0015] [Figure 10] 1 is a top view of a structure including a cross-shaped magnetic concentrator with additional rectangular-shaped magnetic concentrators spaced from each end by gaps, the protective overcoat layer not shown.

[0016] [Figure 11] 1 is a cross-sectional schematic side view of a structure including a substrate, a Hall sensor, a magnetic concentrator having a gap, and a protective overcoat layer.

[0017] [Figure 12] 1 is a top view of a structure including an elliptical magnetic concentrator, illustrating the xy location of the Hall sensors within the structure along with a superimposed quad Hall sensor configuration, with the protective overcoat layer not shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] One aspect of this description is to increase the sensitivity of a Hall sensor using a combination of a magnetic concentrator and at least one horizontal Hall sensor. A Hall sensor is a device used to measure the magnitude of a magnetic field. Its output voltage is directly proportional to the magnetic field strength passing through it. Hall sensors are used in proximity sensing, positioning, speed detection, direction detection, rotation detection, and current sensing applications. Hall sensors can be used in magnetic switches or in rotary switches or shifters, where the Hall sensor measures the change in direction or rotation of the switch or shifter.

[0019] A horizontal Hall sensor has a horizontal longitudinal axis, which is parallel to the flat top surface of the substrate, which also extends horizontally. Similarly, a vertical Hall sensor has a vertical longitudinal axis, which is perpendicular to the flat top horizontal surface of the substrate. A horizontal Hall sensor measures a vertical magnetic field, and conversely a vertical Hall sensor measures a horizontal magnetic field. The use of the terms "horizontal" and "vertical" should not be construed as being limited with reference only to the ground, but should be interpreted with respect to elements of the structure. For example, the structure of FIG. 1 may be rotated, for example, 90°. With this rotation, the horizontal Hall sensor 120 is still considered a "horizontal Hall sensor" and still measures a vertical magnetic field. Other terms such as "top", "bottom", "upper" and "lower" should be interpreted similarly.

[0020] In one example, FIG. 1 shows a cross-sectional schematic side view of a structure 100 including a substrate 110, a Hall sensor 120, an interlevel dielectric oxide layer 125, a magnetic concentrator 130, and a protective overcoat layer 140. The substrate 110 may include Si, glass, ceramic, etc. Below the surface of the substrate are two isolated horizontal Hall sensors 120. The Hall sensors 120 are electrically connected to a circuit (not shown) such that a magnetic field can be measured. The circuit may be integrated on the substrate 110 (e.g., in the interlevel dielectric oxide layer 125) or may be located at a remote location (e.g., on a separate substrate).

[0021] During wafer processing, before the protective overcoat layer 140 is formed and after the Hall sensor 120 is disposed within the substrate 110, the magnetic concentrator 130 is formed (e.g., by a deposition process such as electroplating, sputtering, or spraying) on ​​an upper surface of the interlevel dielectric oxide 125 formed on the upper surface of the substrate 110. Alternatively, the magnetic concentrator 130 may be formed (using any of the processes described above) on an optional stress compensation layer 232 (such as SiN, see FIG. 2 ) that may be deposited on the upper surface of the interlevel dielectric oxide layer 125.

[0022] A magnetic concentrator may include only a single layer of magnetic material or multiple layers of magnetic material, as shown, for example, in FIG. 2. FIG. 2 shows a cross-sectional schematic side view of a structure 200 including a multi-layer magnetic concentrator 230. The magnetic concentrator 230 includes multiple magnetic layers 236, such as NiFe permalloy films (e.g., 330 nm thick). The bottom NiFe magnetic layer 236 is deposited on the upper surface of a layer 234 including Ti or other metal (e.g., 60 nm thick) that can act as an electrode in an electroplating process. The Ti layer 234 is deposited on the upper surface of an interlevel dielectric oxide layer 225 (any thickness) or optional stress compensation layer 232, if present (e.g., 100 nm thick). Above each of the NiFe magnetic layers 236 is an insulating layer 238 including a dielectric material such as AlN or Al2O3 or a high resistivity insulator material (e.g., 10 nm thick). To complete the die, a protective overcoat layer 240 is deposited over the magnetic concentrator 230. Prior to deposition of the overcoat layer 240, the magnetic concentrator 230 is patterned.

[0023] In this example, multiple magnetic layers are used because, among other things, a thicker and therefore stronger concentrator material is realized. A thicker magnetic concentrator also provides a higher saturation threshold. By providing multiple layers of magnetic material, the multi-layer magnetic concentrator is made thicker, thus preventing saturation of the magnetic field within the magnetic concentrator. A high saturation threshold allows the magnetic concentrator to withstand a significantly higher magnetic field input, and therefore provide a higher magnetic field output. If the magnetic concentrator saturates, the structure including the substrate and the Hall sensor becomes non-linear and ceases to function. Therefore, it is highly desirable to prevent saturation within the magnetic concentrator.

[0024] Importantly, the magnetic concentrator is formed during wafer-level processing. This wafer-level deposition process (compared to pick-and-place deposition) allows for precise patterning of the magnetic concentrator. The patterning of the magnetic concentrator allows for any shape of the magnetic concentrator in the xy direction, thereby achieving flexibility in controlling the magnetic field enhancement. Specifically, the magnetic concentrator is located between the protective overcoat layer 240 and the interlevel dielectric oxide layer 225 (or optional stress compensation layer 232, if present). The interlevel dielectric oxide layer 225 contains metal routing for the Hall sensor and associated integrated circuits.

[0025] In one implementation, protective overcoat layer 240 is a layer of SiON or other dielectric material (e.g., 2.8 μm thick), although other thicknesses can alternatively be used. Placing the concentrator in this location (i.e., below protective overcoat layer 240) rather than above it increases the effectiveness of the magnetic concentrator by decreasing the distance between the magnetic concentrator and the Hall sensor.

[0026] 2, the magnetic concentrator 230 may include an outer layer 239 of, for example, Ti or other polymer (e.g., 135 nanometers thick). The Ti outer layer 239 acts as a protective layer surrounding the plurality of NiFe magnetic layers 236. The Ti outer layer 239 protects the plurality of NiFe magnetic layers 236 from mechanical damage, for example, during packaging or other manufacturing steps. The Ti outer layer 239 is patterned similarly to the underlying Ti layer 234, particularly toward the sides of the plurality of NiFe magnetic layers 236. The mask may extend the Ti some distance away from the NiFe layers.

[0027] As mentioned above, the Ti layer 234 may be disposed between the bottom NiFe magnetic layer 236 and the optional underlying SiN stress compensation layer 232. The Ti layer 234 may act as an electrode in an electroplating process for the deposition of multiple NiFe magnetic layers. The Ti layer 234 also blocks diffusion of the magnetic NiFe material into the underlying stress compensation layer 232 during the NiFe deposition (e.g., electroplating or sputtering) process. Thus, the Ti layer 234 prevents diffusion of NiFe into the SiN, which may adversely affect the operation (and possibly the formation) of the Hall sensor. The optional SiN stress compensation layer 232 compensates for mechanical stresses that may be induced on the wafer during deposition of the magnetic concentrator 230. Instead of electroplating, sputtering may be used to deposit the NiFe and AlN layers, followed by a wet etch to pattern the NiFe layer. The wet etch on the stacked core results in the stepped sidewalls shown in FIG. 2. Alternatively, a dry etch may be used.

[0028] To pattern the magnetic concentrators, a photoresist is used during the electroplating process in forming the NiFe magnetic layer to prevent deposition of NiFe on certain areas of the substrate. Following electroplating, the photoresist is stripped, thereby patterning the magnetic concentrators. The patterning of the magnetic concentrators results in the formation of magnetic concentrators having various shapes, as described below.

[0029] In one example, FIG. 5A shows a top view of a structure 500 including a substrate 510 and an elliptical magnetic concentrator 530. FIG. 5B is a top view of the structure 500 shown in FIG. 5A, illustrating the Hall sensor 520 superimposed thereon, as well as the xy position of the Hall sensor 520 within the structure. The magnetic concentrator 530 may have a thickness / depth in the range of, for example, 1-2 μm. The substrate may have a width in the range of 0.7 mm-2 mm, and a depth / thickness in the range of 60-800 μm. The Hall sensor 520 may have a thickness (i.e., the depth of the Hall well) in the range of 1-3 μm and may be spaced a distance of 3-5 μm from the substrate top surface. The protective overcoat layer (not shown) may have any thickness.

[0030] In one example, Figure 6A shows a top view of a structure 600 including a substrate 610 and a wedge-shaped magnetic concentrator 630. Figure 6B is a top view of the structure 600 shown in Figure 6A, illustrating the Hall sensor 620 superimposed thereon, as well as the xy position of the Hall sensor 620 within the structure.

[0031] In one example, Figure 7A shows a top view of a structure 700 including a substrate 710 and a circular magnetic concentrator 730. Figure 7B is a top view of the structure 700 shown in Figure 7A, illustrating the Hall sensor 720 superimposed thereon, as well as the xy position of the Hall sensor 720 within the structure.

[0032] In one example, Figure 8A shows a top view of a structure 800 including a substrate 810 and a cross-shaped magnetic concentrator 830. Figure 8B is a top view of the structure 800 shown in Figure 8A, illustrating the Hall sensor 820 superimposed thereon, as well as the xy position of the Hall sensor 820 within the structure.

[0033] In one example, Figure 9A shows a top view of a structure 900 including a substrate 910 and an "X" shaped magnetic concentrator 930. Figure 9B is a top view of the structure 900 shown in Figure 9A, illustrating the Hall sensor 920 superimposed thereon, as well as the xy position of the Hall sensor 920 within the structure.

[0034] Various patterned shapes of these magnetic concentrators enable higher structural sensitivity by enhancing / amplifying the magnetic field near the area of ​​the Hall sensor. Different magnetic concentrator shapes enhance the magnetic field by providing different magnetic field outputs while concentrating the output near the Hall sensor. Table 1 below shows the maximum magnetic field output from magnetic concentrators of various exemplary shapes (e.g., rectangular, elliptical, etc.) with an applied horizontal magnetic flux of 1 mT. For example, applying a horizontal magnetic flux of 1 mT to an elliptical magnetic concentrator can amplify the magnetic field output up to 8.5 mT. Table 1 Magnetic field enhancement / amplification depending on the shape of the magnetic concentrator TIFF0007658044000001.tif2767

[0035] Hall sensors are placed under each end of the magnetic concentrator (see Figures 5B, 6B, 7B, 8B, and 9B). Any number of Hall sensors is contemplated. However, 1D magnetic field measurements may be made using one or more Hall sensors. Because the Hall voltage changes polarity with changing magnetic field direction, a single Hall sensor can be used to determine the direction of the magnetic field. 2D magnetic field measurements may be made using two or more Hall sensors. 3D magnetic field measurements may be made using four or more Hall sensors.

[0036] Referring again to FIG. 1, when a magnetic field (B) is applied horizontally from the side, the magnetic concentrator 130 concentrates the magnetic field. Because this concentration occurs at the end of the magnetic concentrator, the magnetic field may bend and transform from horizontal to vertical. With this transformation, the horizontally applied magnetic field (B) loops and bends into a vertical magnetic field once it enters the substrate. In other words, the in-plane (xy) bidirectional input magnetic field is transformed into an out-of-plane (z) bidirectional output magnetic field. The horizontal Hall sensors 120 are placed in the vertical magnetic field to maximize their measurements of the magnetic field in the z direction. Importantly, in this configuration, no vertical Hall sensors (measuring magnetic fields applied horizontally from the side) are needed in the structure.

[0037] For simplicity, Figures 3-10 and 12 do not show the protective overcoat layer.

[0038] In one example, Figure 3 shows a top view of a structure 300 including a substrate 310 and a cross-shaped magnetic concentrator 330, where a magnetic field input is applied in the horizontal (X) direction. A magnetic field of lmT applied in the x-direction results in a maximum output of 14mT in the z-direction. With this structure, sensitivity enhancement / amplification of the magnetic field by a factor of up to 14 can be achieved.

[0039] In one example, Figure 4 shows a top view of a structure 400 including a substrate 410 and a cross-shaped magnetic concentrator 430, where the magnetic field input is applied in the diagonal (xy) directions. A magnetic field of lmT applied in the xy direction results in a maximum output of 10mT in the z direction. With this structure, sensitivity enhancement / amplification of the magnetic field by up to 10 times can be achieved.

[0040] The Hall sensors are shown in the figures as rectangular in shape in top view, but may be other shapes such as crosses. Also, any single Hall sensor may alternatively be replaced with an array (i.e., two or more) of Hall sensors. The array (assembly) is made by interconnecting two or four sensors together in a particular array. The purpose of the array is to reduce offset and resistance. Offset adversely affects sensor accuracy. Resistance also introduces thermal noise and sets voltage headroom. In one example, FIG. 12 shows a top view of a structure 1200 including a substrate 1210 and an elliptical magnetic concentrator 1230, along with a superimposed quad Hall sensor configuration showing the xy location of the Hall sensors within the structure. Specifically, an array 1220 of four Hall sensors (i.e., a quad) is placed under the end of each magnetic concentrator.

[0041] In one example, Figure 10 shows a top view of a structure 1000 including a substrate 1010 and a cross-shaped magnetic concentrator 1030, with additional magnetic concentrators 1031, e.g., rectangular shaped, spaced from each end by gaps 1060. The use of additional magnetic concentrators provides additional increases in magnetic field output. Hall sensors may be located under the ends of the main / central magnetic concentrator, as in any of the examples above, and may optionally be provided under the gaps and / or under the additional magnetic concentrators.

[0042] In one example, FIG. 11 shows a cross-sectional schematic side view of a structure 1100 including a substrate 1110, a horizontal Hall sensor 1120, a rectangular shaped magnetic concentrator 1130 with a gap 1160, and a protective overcoat layer 1140. The Hall sensor 1121 below the gap 1160 is a vertical Hall sensor because it is disposed in the horizontal magnetic field 1108. In another example, the vertical Hall sensor may be replaced with a horizontal Hall sensor to measure and provide a different magnetic field effect. However, in any of the above examples, using only a horizontal Hall sensor eliminates the need to align the Hall sensors to each other in terms of calibration, while using both horizontal and vertical Hall sensors requires calibration, which adds significant complexity and time for wafer fabrication and packaging.

[0043] 1 , in at least one example, a structure includes a substrate including a surface. The structure also includes a horizontal Hall sensor disposed within the substrate and below the surface of the substrate. The structure further includes a patterned magnetic concentrator disposed above the surface of the substrate, and a protective overcoat layer disposed above the magnetic concentrator.

[0044] The patterned magnetic concentrator may include multiple magnetic layers. The multiple magnetic layers may include a composition selected from the group consisting of Ni, Co, Fe, NiFe, CoNiFe, CoTaZr, and combinations thereof. The multiple magnetic layers may be separated from each other via an insulating layer that includes a composition selected from the group consisting of AlN, Al2O3 (or other dielectric or high resistivity insulator materials), and combinations thereof.

[0045] The patterned magnetic concentrator may further include a conductive metal layer disposed beneath the plurality of magnetic layers. The conductive metal layer may include a composition selected from the group consisting of Ti, W, Cu, and combinations thereof.

[0046] The patterned magnetic concentrator may further include an outer layer at least partially covering the plurality of magnetic layers. The outer layer may include a composition selected from the group consisting of Ti, SiN, SiO2, SiON, and combinations thereof.

[0047] The patterned magnetic concentrators may include shapes selected from the group consisting of non-circular, rectangular, elliptical, wedge, square, diamond, X-shaped, star, cross, triangular, hexagonal, octagonal, and combinations thereof.

[0048] In one example, the structure may further include a vertical Hall sensor disposed within the substrate and below the surface of the substrate. The patterned magnetic concentrator includes a gap at an inner portion of the patterned magnetic concentrator. The vertical Hall sensor is disposed below the gap. The horizontal Hall sensor includes a plurality of Hall sensors disposed below respective outer edge portions of the patterned magnetic concentrator.

[0049] 2, in another example, a method of forming a structure includes forming a substrate including a surface, disposing a horizontal Hall sensor in the substrate and below the surface of the substrate, forming a magnetic concentrator on the surface of the substrate, and forming a protective overcoat layer on the magnetic concentrator. Forming the magnetic concentrator may include a deposition process selected from the group consisting of electroplating, sputtering, spraying, and combinations thereof. Forming the magnetic concentrator may include patterning and etching the deposited magnetic concentrator to form a patterned magnetic concentrator.

[0050] The magnetic concentrator may include multiple magnetic layers. The multiple magnetic layers may include a composition selected from the group consisting of Ni, Co, Fe, NiFe, CoNiFe, CoTaZr, and combinations thereof. The multiple magnetic layers may be separated from each other via an insulating layer that includes a composition selected from the group consisting of AlN, Al2O3 (or other dielectric or high resistivity insulator materials), and combinations thereof.

[0051] The magnetic concentrator may further include a conductive metal layer disposed beneath the plurality of magnetic layers. The conductive metal layer may include a composition selected from the group consisting of Ti, W, Cu, and combinations thereof.

[0052] The magnetic concentrator may further include an outer layer at least partially covering the plurality of magnetic layers. The outer layer may include a composition selected from the group consisting of Ti, SiN, SiO2, SiON, and combinations thereof.

[0053] The patterned magnetic concentrators may include shapes selected from the group consisting of circular, non-circular, rectangular, elliptical, wedge, square, diamond, X-shaped, star, cross, triangle, hexagon, octagon, and combinations thereof.

[0054] In one example, a method of forming a structure can further include disposing a vertical Hall sensor in the substrate and below a surface of the substrate. The patterned magnetic concentrator includes a gap at an inner portion of the patterned magnetic concentrator. The vertical Hall sensor is disposed below the gap. The horizontal Hall sensor includes a plurality of Hall sensors disposed below respective outer edge portions of the patterned magnetic concentrator.

[0055] With reference to FIG. 3, in yet another example, a method includes applying a substantially horizontal magnetic field to a patterned magnetic concentrator, which converts the substantially horizontal magnetic field into a substantially vertical magnetic field. The patterned magnetic concentrator is disposed below a protective overcoat layer and above a surface of a substrate. The substantially vertical magnetic field is applied to two horizontal Hall sensors disposed in the substrate and below the surface of the substrate. The method also includes sensing the substantially vertical magnetic field with the two horizontal Hall sensors. The patterned magnetic concentrator may include multiple magnetic layers.

[0056] The use of patterned magnetic concentrators allows for signal amplification in the conversion from horizontal to vertical magnetic fields during operation of the structure. The magnetic concentrators can amplify the substantially horizontal magnetic field by a factor ranging from 2 to 20 (depending on the shape of the patterned magnetic concentrator), thereby providing a substantially vertical magnetic field. Some shapes can produce conversion factors less than 2, which have also proven useful.

[0057] The patterned magnetic concentrators may include shapes selected from the group consisting of circular, non-circular, rectangular, elliptical, wedge, square, diamond, X-shaped, star, cross, triangle, hexagon, octagon, and combinations thereof.

[0058] As explained in the above example, the magnetic concentrator placed on the substrate surface converts the horizontal magnetic flux into a vertical magnetic flux, which allows horizontal (in-plane) magnetic flux measurement with a horizontal Hall sensor. Also, by patterning the magnetic concentrator into a certain shape, the magnetic field concentration can be increased near the Hall sensor area.

[0059] It should be noted that while four terminals and a rectangular shape are typical for Hall sensors, Hall sensors having other numbers of terminals and / or shapes may be contemplated herein. One example is an eight terminal octagonal shape.

[0060] As used herein, the term "couple" means either an indirect or direct wired or wireless connection. Thus, if a first device couples to a second device, the connection may be through a direct connection or through an indirect connection via other devices and connections. "Based on" means "based at least in part on." Thus, if X is based on Y, then X may be a function of Y and any number of other factors.

[0061] Modifications may be made to the exemplary embodiments described, and other embodiments are possible, within the scope of the invention.

Claims

1. A structure comprising: a substrate including a surface; a horizontal Hall sensor disposed within the substrate and below the surface of the substrate; a patterned magnetic concentrator disposed over the surface of the substrate; a protective overcoat layer disposed over the magnetic concentrator; a stress compensation layer disposed on the substrate; A structure in which the magnetic concentrator includes a plurality of magnetic layers isolated from one another by an insulating layer and a conductive metal layer disposed below the plurality of magnetic layers, a lowest magnetic layer of the plurality of magnetic layers being formed on a surface of the conductive metal layer, and the conductive metal layer being formed between the plurality of magnetic layers and the stress compensation layer.

2. 2. The structure of claim 1, wherein the magnetic layers include a composition selected from the group consisting of Ni, Co, Fe, NiFe, CoNiFe, CoTaZr, and combinations thereof, and the insulating layer includes a composition selected from the group consisting of AlN, Al ２ O ３ and combinations thereof.

3. 10. The structure of claim 1, wherein the conductive metal layer comprises a composition selected from the group consisting of Ti, W, Cu, and combinations thereof.

4. 10. The structure of claim 1, wherein the patterned magnetic concentrator further comprises an outer layer at least partially covering the plurality of magnetic layers, the outer layer being selected from the group consisting of Ti, SiN, SiO ２ , SiON, and combinations thereof.

5. 10. The structure of claim 1, wherein the patterned magnetic concentrators comprise a shape selected from the group consisting of non-circular, rectangular, elliptical, wedge, square, diamond, X-shaped, star, cross, triangle, hexagon, octagon, and combinations thereof.

6. 2. The structure of claim 1 further comprising a vertical Hall sensor disposed within the substrate and below the surface of the substrate, the patterned magnetic concentrator including a gap at an inner portion of the patterned magnetic concentrator, the vertical Hall sensor disposed below the gap, and the horizontal Hall sensor including a plurality of Hall sensors disposed below outer edge portions, respectively, of the patterned magnetic concentrator.

7. 1. A method of forming a structure, the method comprising: providing a substrate including a surface; disposing a horizontal Hall sensor within the substrate and below the surface of the substrate; disposing a stress compensation layer over the substrate; forming a magnetic concentrator on the surface of the substrate; forming a protective overcoat layer over the magnetic concentrator; The method, wherein the magnetic concentrator includes a plurality of magnetic layers isolated from one another by an insulating layer and a conductive metal layer disposed below the plurality of magnetic layers, a lowest magnetic layer of the plurality of magnetic layers being formed on a surface of the conductive metal layer, and the conductive metal layer being formed between the plurality of magnetic layers and the stress compensation layer.

8. 8. The method of claim 7, wherein forming the magnetic concentrator comprises a deposition process selected from the group consisting of electroplating, sputtering, spraying, and combinations thereof.

9. 8. The method of claim 7, wherein forming the magnetic concentrator comprises forming a patterned magnetic concentrator by patterning and etching a deposited magnetic concentrator.

10. 8. The method of claim 7, wherein the magnetic layers include a composition selected from the group consisting of Ni, Co, Fe, NiFe, CoNiFe, CoTaZr, and combinations thereof, and the insulating layer includes a composition selected from the group consisting of AlN, Al ２ O ３ and combinations thereof.

11. 8. The method of claim 7, wherein the conductive metal layer comprises a composition selected from the group consisting of Ti, W, Cu, and combinations thereof.

12. 8. The method of claim 7, wherein the magnetic concentrator further comprises an outer layer at least partially covering the plurality of magnetic layers, the outer layer being selected from the group consisting of Ti, SiN, SiO. ２ , SiON, and combinations thereof.

13. 10. The method of claim 9, wherein the patterned magnetic concentrators comprise a shape selected from the group consisting of a circle, a non-circle, a rectangle, an ellipse, a wedge, a square, a diamond, an X-shape, a star, a cross, a triangle, a hexagon, an octagon, and combinations thereof.

14. 10. The method of claim 9, further comprising disposing a vertical Hall sensor in the substrate and below the surface of the substrate, the patterned magnetic concentrator including a gap at an inner portion of the patterned magnetic concentrator, the vertical Hall sensor disposed below the gap, and the horizontal Hall sensor including a plurality of Hall sensors disposed below outer edge portions of the patterned magnetic concentrator.

15. 1. A method comprising: applying a substantially horizontal magnetic field to a patterned magnetic concentrator, the patterned magnetic concentrator converting the substantially horizontal magnetic field into a substantially vertical magnetic field, the patterned magnetic concentrator being disposed below a protective overcoat layer and above a surface of a substrate, the magnetic concentrator including a plurality of magnetic layers isolated from each other via an insulating layer and a conductive metal layer disposed below the plurality of magnetic layers, a lowest magnetic layer of the plurality of magnetic layers being formed on the surface of the conductive metal layer, the substantially vertical magnetic field being applied to two horizontal Hall sensors disposed within the substrate and below the surface of the substrate; sensing the substantially perpendicular magnetic field with the two horizontal Hall sensors; wherein the conductive metal layer is formed between the plurality of magnetic layers and a stress compensation layer formed on a substrate.

16. 16. The method of claim 15, wherein the patterned magnetic concentrator amplifies the substantially horizontal magnetic field by a factor in the range of 2 to 20, thereby providing the substantially vertical magnetic field.

17. 16. The method of claim 15, wherein the patterned magnetic concentrators comprise a shape selected from the group consisting of circular, non-circular, rectangular, elliptical, wedge, square, diamond, X-shaped, star, cross, triangle, hexagon, octagon, and combinations thereof.

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