Magnetic sensor device and method for producing a magnetic sensor device

Abstract

The invention relates to a magnetic sensor device comprising a substrate (10) having a substrate surface (10a); at least one first measuring bridge (12a), each first measuring bridge having first magnetoresistive elements (14a) by means of which a first measurement variable relating to a first magnetic field strength in a first sensing direction running parallel to the substrate surface (10a) can be determined, the first sensing direction being parallel to a respective first magnetization direction of the reference layers (18) of the first magnetoresistive elements (14a); and at least one soft-magnetic shielding element (26a, 26b). At least one of the first magnetoresistive elements (14a) has a magnetic vortex (28) in the free layer (16) thereof or at least one of the first magnetoresistive elements (14a) has a free layer (16) which lies, in each case, between a first hard-magnetic region and a second hard-magnetic region. The invention likewise relates to a method for producing a magnetic sensor device.

Description

[0001] R. 411380

[0002] - 1 -

[0003] Description

[0004] title

[0005] Magnetic sensor device and manufacturing process for a magnetic sensor device

[0006] The present invention relates to a magnetic sensor device. The present invention also relates to a manufacturing method for a magnetic sensor device.

[0007] State of the art

[0008] US patent 11,002,805 B2 discloses a magnetic sensor system comprising measuring bridges arranged over the surface of a substrate and designed with magnetoresistive elements. The magnetic sensor system also includes soft magnetic shielding elements arranged either between the substrate surface and the at least one associated measuring bridge or on a side of the at least one associated measuring bridge facing away from the substrate. Furthermore, US patent 11,002,805 B2 discloses the use of flux deflectors for deflecting a magnetic field component oriented perpendicular to the substrate surface into a respective sensing direction of the measuring bridges.

[0009] Disclosure of the invention

[0010] The present invention provides a magnetic sensor device with the features of claim 1 and a manufacturing method for a magnetic sensor device with the features of claim 12. R. 411380

[0011] - 2 -

[0012] Advantages of the invention

[0013] The present invention provides magnetic sensor devices which, due to the at least one soft magnetic shielding element and the at least one magnetic vortex or hard magnetic areas, are particularly well suited for high-field applications. It is especially noted that, despite their suitability for high-field applications, the magnetic sensor devices according to the invention are generally less susceptible to interference compared to the prior art. In addition, the magnetic sensor devices according to the invention feature a sensor design with a significantly smaller footprint compared to the prior art. The space savings achievable with the present invention also contribute to cost savings in the manufacture of the magnetic sensor devices according to the invention.Furthermore, the space savings facilitate the packaging of the magnetic sensor devices according to the invention, which often contributes to additional cost reductions in the manufacture of the magnetic sensor device according to the invention.

[0014] In an advantageous embodiment of the magnetic sensor device, the first magnetic field strength can be determined as the first measured quantity within a structurally defined first range of values ​​by means of at least one first measuring bridge, wherein the first range of values ​​extends from a minimum limit of less than or equal to -10 mT to a maximum limit of greater than or equal to 10 mT. The embodiment of the magnetic sensor device described here thus represents an advantageous high-field solution.

[0015] Preferably, the first range of values ​​extends from a minimum limit of less than or equal to -15 mT to a maximum limit of greater than or equal to 15 mT. In particular, the first range of values ​​can extend from a minimum limit of less than or equal to -20 mT (millitesla) to a maximum limit of greater than or equal to 20 mT (millitesla), specifically from a minimum R. 411380

[0016] - 3 -

[0017] The limit value can extend from less than or equal to -25 mT (millitesla) to a maximum limit value greater than or equal to 25 mT (millitesla), also from a minimum limit value less than or equal to -50 mT (millitesla) to a maximum limit value greater than or equal to 50 mT (millitesla), advantageously from a minimum limit value less than or equal to -100 mT (millitesla) to a maximum limit value greater than or equal to 100 mT (millitesla), preferably from a minimum limit value less than or equal to -250 mT (millitesla) to a maximum limit value greater than or equal to 250 mT (millitesla), and preferably from a minimum limit value less than or equal to -500 mT (millitesla) to a maximum limit value greater than or equal to 500 mT (millitesla). The embodiment described here can therefore be advantageously used as a so-called magnetoresistive high-field sensor.

[0018] In a further advantageous embodiment, the magnetic sensor device comprises at least one flux deflection structure by means of which a magnetic field component extending perpendicular to the substrate surface can be deflected into the first sensing direction. The magnetic sensor device described here can thus be used, in particular for high-field applications, to determine the first measured quantity for a magnetic field component oriented perpendicular to the substrate surface.

[0019] In a particularly material-saving embodiment of the magnetic sensor device, the at least one flux deflection structure is formed as part of the at least one soft magnetic shielding element on a side of the respective soft magnetic shielding element oriented towards at least one first measuring bridge. The design of the at least one soft magnetic shielding element described here facilitates miniaturization of the magnetic sensor device, even though it is designed for high-field applications.

[0020] As an advantageous further development, the magnetic sensor device can comprise at least a second measuring bridge, each with second magnetoresistive elements, wherein at least one of the second measuring bridges is located on and / or above the substrate surface or a further substrate surface of a further R. 411380

[0021] - 4 -

[0022] The embodiment is arranged on the substrate, and a second measurement parameter relating to a second magnetic field strength in a second sensing direction, which is parallel to the substrate surface or the further substrate surface and parallel to a respective second magnetization direction of the reference positions of the second magnetoresistive elements, can be determined by means of at least one second measuring bridge. The embodiment described here can therefore be used as a 2D magnetic sensor, in particular as a 2D high-field sensor.

[0023] Additionally, the magnetic sensor device can comprise at least one third measuring bridge, each with third magnetoresistive elements, wherein at least one third measuring bridge is arranged on and / or above the substrate surface or the further substrate surface, and wherein a third measured quantity with respect to a third magnetic field strength in a third sensing direction, which is parallel to the substrate surface or the further substrate surface and parallel to a respective third magnetization direction of the reference positions of the third magnetoresistive elements, can be determined by means of at least one third measuring bridge. The embodiment described here can thus also be used as a so-called 3D magnetic sensor, particularly for high-field applications.

[0024] Preferably, at least one of the second magnetoresistive elements and / or at least one of the third magnetoresistive elements exhibits a magnetic vortex in its free position. Thus, the second magnetic field strength as the second measured quantity and / or the third magnetic field strength as the third measured quantity can each be determined within a structurally defined second / third range of values, wherein the second / third range of values ​​extends (at least) from a minimum limit of less than or equal to -10 mT (millitesla) to a maximum limit of greater than or equal to 10 mT (millitesla).

[0025] Alternatively, R. 411380 can also be used for at least one of the second magnetoresistive elements and / or at least one of the third magnetoresistive elements.

[0026] - 5 - whose free position lies between each first hard magnetic region and each second hard magnetic region. This also ensures a comparatively large second / third value range, which extends (at least) from a minimum limit of less than or equal to -10 mT (millitesla) to a maximum limit of greater than or equal to 10 mT (millitesla).

[0027] In a particularly advantageous embodiment, the second sensing direction is aligned perpendicular to the first sensing direction and / or perpendicular to the third sensing direction. This allows the magnetic sensor device described here to be used as a so-called 3D sensor for measuring a magnetic field in three orthogonally aligned spatial axes, especially for high-field applications.

[0028] Optionally, the first magnetoresistive elements, the second magnetoresistive elements, and / or the third magnetoresistive elements can be at least one TMR element and / or at least one GMR element. This allows for considerable design freedom in the configuration of the magnetoresistive elements of the magnetic sensor device.

[0029] The advantages described above can also be achieved by implementing a corresponding manufacturing process for a magnetic sensor device. It is expressly noted that the manufacturing process can be further developed according to the embodiments of magnetic sensor devices described above.

[0030] Brief description of the drawings

[0031] Further features and advantages of the present invention are explained below with reference to the figures. They show:

[0032] Figs. 1a and 1b schematic representations of a first embodiment of the magnetic sensor device; R. 411380

[0033] Figs. 2a and 2b are schematic representations of a second embodiment of the magnetic sensor device;

[0034] Figs. 3a and 3b are schematic representations of a third embodiment of the magnetic sensor device;

[0035] Figs. 4a and 4b are schematic representations of a fourth embodiment of the magnetic sensor device; and

[0036] Fig. 5 is a flowchart to explain one embodiment of the manufacturing process for a magnetic sensor device.

[0037] Embodiments of the invention

[0038] Figs. 1a and 1b show schematic representations of a first embodiment of the magnetic sensor device.

[0039] The magnetic sensor device schematically depicted in Figs. 1a and 1b has a substrate 10 with a substrate surface 10a, wherein at least one first measuring bridge 12a is arranged on and / or above the substrate surface 10a. The substrate 10 can be, for example, a semiconductor substrate, such as, in particular, a silicon substrate. The at least one first measuring bridge 12a can be a half-bridge and / or a full bridge. In particular, the at least one first measuring bridge 12a can be a Wheatstone bridge.

[0040] Furthermore, at least one first measuring bridge 12a is each configured with first magnetoresistive elements 14a. The first magnetoresistive elements 14a can be at least one TMR element and / or at least one GMR element. In both cases, the first magnetoresistive elements 14a each have a free layer 16 and a reference layer 18. In contrast to the magnetization of the free layer 16, the first magnetization direction 20a of the reference layer 18 of the same R. 411380

[0041] - 7 - the first magnetoresistive element 14a is not / hardly affected by a prevailing magnetic field. As can be seen in Fig. 1a, the respective first magnetization directions 20a of the reference positions 18 of the first magnetoresistive elements 14a are aligned parallel / antiparallel to each other. In addition, the respective first magnetization directions 20a of the reference positions 18 of the first magnetoresistive elements 14a are aligned parallel to the substrate surface 10a.

[0042] As shown in Fig. 1b, a spacer layer 22 is located between the free layer 16 and the reference layer 18 of the same first magnetoresistive element 14a. In the case of a TMR element, the spacer layer 22 (also called the tunnel barrier) is an electrically non-conductive layer, typically made of Al₂O₃ or MgO. In contrast, in the case of a GMR element, the spacer layer 22 is an electrically conductive layer. The relative orientation of a given magnetization of the free layer 16 to the respective first magnetization direction 20a of the reference layer 18 of the same first magnetoresistive element 14a influences the resistance of the respective first magnetoresistive element 14a. Typically, an antiferromagnetic layer 24 may also be formed, e.g., on a side of the reference layer 18 facing away from the free layer 16.The respective antiferromagnetic layer 24 can optionally be in direct contact with the reference layer 18 or with at least one intermediate (not shown) layer.

[0043] By means of at least one first measuring bridge 12a isl, a first measured quantity Z+ and Z- with respect to a first magnetic field strength in a first sensing direction can be determined / determined during operation of the magnetic sensor device described here. The first magnetization directions 20a of the reference positions 18 of the first magnetoresistive elements 14a define the first sensing direction, in that the first sensing direction is aligned parallel to the respective first magnetization direction 20a of the reference positions 18 of the first magnetoresistive elements 14a. Therefore, the first sensing direction is to be understood as an axis which is parallel to the R. 411380

[0044] - 8 -

[0045] The first magnetoresistive elements 14a can therefore be called “ln-plane” sensor elements, i.e. sensor elements whose sensitive axis runs parallel to a surface contacted by the sensor elements, or to the substrate surface 10a.

[0046] Furthermore, the magnetic sensor device of Figures 1a and 1b comprises at least one soft magnetic shielding element 26a and 26b, which is arranged between the substrate surface 10a and at least one first measuring bridge 12a and / or on a side of at least one first measuring bridge 12a facing away from the substrate 10. Preferably, the magnetic sensor device has a first soft magnetic shielding element 26a (bottom shield) between the substrate surface 10a and at least one first measuring bridge 12a, while a second soft magnetic shielding element 26b (top shield) is located on a side of at least one first measuring bridge 12a facing away from the substrate 10. The at least one soft magnetic shielding element 26a and 26b consists of at least one soft magnetic material. Preferably, the at least one soft magnetic shielding element 26a and 26b is made of nickel-iron.For example, at least one soft magnetic shielding element 26a and 26b can be formed from a nickel-iron alloy with a nickel content of between 70 wt.% and 90 wt.% and an iron content of between 10 wt.% and 30 wt.%. To form the at least one soft magnetic shielding element 26a and 26b from such a nickel-iron alloy, a selective electrogalvanic process, a so-called selective plating, can be carried out by first forming an electrically conductive seed layer from at least one electrically conductive material into a desired initial shape and then growing the respective soft magnetic shielding element 26a and 26b from the nickel-iron alloy onto exposed surfaces of the electrically conductive seed layer.The soft magnetic shielding element 26a and 26b is therefore relatively easy to manufacture, even though nickel-iron alloys are comparatively difficult to etch. R. 411380.

[0047] - 9 -

[0048] A nickel-iron alloy with a nickel content of 81 wt.% and an iron content of 19 wt.% is preferred for the at least one soft magnetic shielding element 26a and 26b.

[0049] Additionally, at least one of the first magnetoresistive elements 14a exhibits a magnetic vortex 28 in its free position 16. This can also be described as the respective first magnetoresistive element 14a having a magnetic vortex structure in its free position / free magnetization layer 16, comprising a vortex core and a vortex border region. The vortex core exhibits magnetization out of a plane, while the vortex border region forms a vortex structure around the vortex core that is magnetized in the plane. Magnetic vortices 28 can be the energetic ground state in magnetic nanodots. They can, for example, have a (generally) round geometry with a diameter of approximately 200–800 nm (nanometers) and a thickness of 50–100 nm (nanometers). (Magnetic vortices are, for example, found in the following examples:

[0050] (described in "https: / / pubmed.ncbi.nlm.nih.gOv / 10937991 / "). A TMR element or GMR element with a magnetic vortex 28 can also be referred to as a vortex-TMR element or vortex-GMR element. The formation of at least one free layer 16 of the first magnetoresistive elements 14a with the magnetic vortices 28 can improve the suitability of the magnetic sensor device for high-field applications.

[0051] Using the magnetic sensor device described here, the first magnetic field strength, as the first measured quantity Z+ and Z-, can therefore be determined with at least one first measuring bridge 12a within a structurally defined first range of values, wherein the first range of values ​​extends from a minimum limit of less than or equal to 10 mT (millitesla) to a maximum limit of greater than or equal to 10 mT (millitesla). The magnetic sensor device described here can therefore be advantageously used for high-field applications. Preferably, the first range of values ​​extends from a minimum limit of less than or equal to -15 mT (millitesla) to a maximum limit of greater than or equal to 15 mT (millitesla). (Vortex-TM R- elements and Vortex-R. 411380

[0052] - 10 -

[0053] GMR elements can often intrinsically achieve an initial value range between -100 mT and 100 mT.In particular, the first range of values ​​can be from a minimum limit less than or equal to -20 mT (millitesla) to a maximum limit greater than or equal to 20 mT (millitesla), specifically from a minimum limit less than or equal to -25 mT (millitesla) to a maximum limit greater than or equal to 25 mT (millitesla), also from a minimum limit less than or equal to -50 mT (millitesla) to a maximum limit greater than or equal to 50 mT (millitesla), advantageously from a minimum limit less than or equal to -100 mT (millitesla) to a maximum limit greater than or equal to 100 mT (millitesla), preferably from a minimum limit less than or equal to -250 mT (millitesla) to a maximum limit greater than or equal to 250 mT (millitesla), and more preferably from a minimum limit less than or equal to -500 mT (millitesla) to a maximum limit greater than or equal to 500 mT (Millitesla), extend. The embodiment described here in Fig.1a and 1b can therefore be advantageously used as a so-called magnetoresistive high-field sensor.

[0054] Preferably, the magnetic sensor device has at least one flux deflection structure 30 by means of which a magnetic field component extending perpendicular to the substrate surface 10a (i.e., a magnetic field component extending in the spatial direction z) can be deflected / is deflected into the first sensing direction. Thus, the first magnetoresistive elements 14a, which can be manufactured cheaply as "ln-plane" sensor elements, can still be used to measure the magnetic field component extending perpendicular to the substrate surface 10a, despite their first sensing direction being aligned parallel to the substrate surface 10a.

[0055] The at least one flux deflection structure 30 can, in particular, be a flux guide. The at least one flux deflection structure 30 is also preferably formed from at least one soft magnetic material. Optionally, the at least one flux deflection structure 30 can be made of the same material as the at least one soft magnetic shielding element 26a and 26b or R. 411380.

[0056] - 11 - at least one other material than for which at least one soft magnetic shielding element 26a and 26b is used.

[0057] By way of example only, in the embodiment described here in Figures 1a and 1b, the at least one flux deflection structure 30 is formed as a soft magnetic part separate from the at least one soft magnetic shielding element 26a and 26b. The at least one flux deflection structure 30 has its maximum extent parallel to the substrate surface 10a. If the maximum extent of the at least one flux deflection structure 30 extends, for example, along a spatial direction y aligned parallel to the substrate surface 10a, the at least one flux deflection structure 30 can deflect magnetic field components extending along the spatial direction z into a sensing direction aligned parallel to a spatial direction x. (The spatial directions x, y, and z are orthogonal to each other.) Preferably, the maximum extent of the at least one flux deflection structure 30 lies in a range between 2 pm (micrometers) and 600 pm (micrometers).For the height of the at least one flux deflection structure 30 in the spatial direction z, values ​​between 0.3 pm (micrometers) and 10 pm (micrometers) are preferred. The width of the respective flux deflection structure 30, oriented perpendicular to its maximum extent and height, advantageously falls within a range between 0.3 pm (micrometers) and 10 pm (micrometers). A conversion factor effected by the at least one flux deflection structure 30 when deflecting the magnetic field component oriented perpendicular to the substrate surface 10a into the first sensing direction can typically be in a range between 0.001 and 0.4. The conversion factor can be determined to a desired value with relatively high accuracy by the relative positioning of the at least one flux deflection structure 30 to the associated first magnetoresistive elements 14a, as well as by the dimensions of the at least one flux deflection structure 30.

[0058] Provided that at least one soft magnetic shielding element 26a and 26b together with at least one flux deflection structure 30 for measuring the magnetic field component R perpendicular to the substrate surface 10a. 411380

[0059] - 12 -

[0060] In the (co-)utilization, the at least one soft magnetic shielding element 26a and 26b is preferably each shaped such that the soft magnetic shielding element 26a and 26b has the same maximum extent along the spatial direction x oriented parallel to the substrate surface 10a and along the spatial direction y oriented parallel to the substrate surface 10a. The at least one shielding element 26a and 26b thus exhibits the same shielding efficiency for both a magnetic field component oriented along the spatial direction x and a magnetic field component oriented along the spatial direction y. Therefore, at least one first measuring bridge 12a is effectively shielded against both a so-called magnetic interference field component oriented along the spatial direction x and against another magnetic interference field component oriented along the spatial direction y.In this context, one can also speak of an "in-plane" shielding of at least the first measuring bridge 12a against magnetic interference field components by means of the at least one soft magnetic shielding element 26a and 26b. Nevertheless, a magnetic field component aligned along the spatial direction z can be deflected into the first sensing direction by means of the at least one flux deflection structure 30. The same maximum extent of the at least one soft magnetic shielding element 26a and 26b along the spatial direction x and along the spatial direction y preferably lies in a range between 2 pm (micrometers) and 600 pm (micrometers). In the spatial direction z, the at least one soft magnetic shielding element 26a and 26b can have a maximum height that is greater than or equal to 0.5 pm (micrometers) and less than or equal to 20 pm (micrometers).In a particularly advantageous embodiment of the magnetic sensor device, the maximum height of the at least one soft magnetic shielding element 26a and 26b lies in a range between 0.5 pm (micrometers) and 10 pm (micrometers).

[0061] As an advantageous further development, the magnetic sensor device of Figs. 1a and 1b has at least a second measuring bridge 12b, each with second magnetoresistive elements 14b, and / or at least a third measuring bridge 12c, each with third magnetoresistive elements 14c, wherein by means of R. 411380

[0062] - 13 - at least one second measuring bridge 12b can determine a second measured quantity X+ and X- with respect to a second magnetic field strength in a second sensing direction and / or a third measured quantity Y+ and Y- with respect to a third magnetic field strength in a third sensing direction can be determined / are determined by means of at least one third measuring bridge 12c. The second / third magnetoresistive elements 14b or 14c also each have a (not shown) reference position with a respective second / third magnetization direction 20b or 20c, wherein all second magnetization directions 20b of the reference positions of the second magnetoresistive elements 14b are aligned parallel / antiparallel to each other and / or all third magnetization directions 20c of the reference positions of the third magnetoresistive elements 14c are aligned parallel / antiparallel to each other.Accordingly, the second / third sensing direction is defined by the respective second / third magnetization direction 20b or 20c of the reference positions of the second / third magnetoresistive elements 14b or 14c, in that the second / third sensing direction is parallel to the second / third magnetization directions 20b or 20c of the reference positions of the second / third magnetoresistive elements 14b or 14c. In particular, the third sensing direction can be oriented perpendicular to the second sensing direction. The magnetic sensor device of Figs. 1a and 1b can thus be configured as a 2D sensor or as a 3D sensor.

[0063] Ideally, at least one first measuring bridge 12a, at least one second measuring bridge 12b, and possibly at least one third measuring bridge 12c are formed on the same substrate surface 10a. This variant offers the greatest potential for space and cost savings. The magnetic sensor device equipped in this way is thus realized as a "single" sensor die. Alternatively, however, at least one second measuring bridge 12b and / or at least one third measuring bridge 12c can also be arranged on another substrate surface of a (not shown) additional substrate. The magnetic sensor device may have several sensor dies integrated into a single package. It is also possible that at least one first measuring bridge 12a, at least one second measuring bridge 12b, and at least R. 411380

[0064] - 14 - a third measuring bridge 12c is used, each with its own substrate surface. The second / third sensing direction can be aligned parallel to the substrate surface 10a or the other substrate surface.

[0065] The at least one second measuring bridge 12b and / or the at least one third measuring bridge 12c can each be a half-bridge and / or a full bridge, specifically a Wheatstone bridge. Furthermore, the at least one first bridge 12a, the at least one second bridge 12b, and the at least one third bridge 12c can be implemented as independent bridges. The measuring bridges 12a, 12b, and 12c can optionally be electrically connected to the same supply voltage U or to different (not shown) supply voltages. Accordingly, the measuring bridges 12a, 12b, and 12c can also be electrically connected to a ground 32. The second magnetoresistive elements 14b and / or the third magnetoresistive elements 14c can be at least one TMR element and / or at least one GMR element.At least one of the second magnetoresistive elements 14b and / or at least one of the third magnetoresistive elements 14c preferably has a magnetic vortex 28 in its free position. This makes the at least one second measuring bridge 14b and / or the at least one third measuring bridge 14c suitable as high-field sensors. The second / third magnetic field strength can thus be determined as the second / third measured quantity X+, X-, Y+, and Y- with at least one second / third measuring bridge 12a within a structurally defined second / third value range, which is comparatively large.

[0066] Preferably, the at least one second measuring bridge 12b and / or the at least one third measuring bridge 12c are arranged in such a way as to the soft magnetic shielding element 26a and 26b associated with the at least one of the at least one first measuring bridge 12a, such that the respective measuring accuracy and / or measuring sensitivity of the at least one second measuring bridge 12b and / or the at least one third measuring bridge 12c is determined by the soft magnetic shielding element 26a and 26b associated with the at least one of the at least one first measuring bridge 12a. R. 411380

[0067] - 15 -

[0068] Shielding elements 26a and 26b are not / hardly affected. If desired, the magnetic sensor device can have at least one further (not shown) soft magnetic shielding element in addition to the soft magnetic shielding element 26a and 26b assigned to at least one of the first measuring bridges 12a. This further soft magnetic shielding element can, for example, be arranged between the substrate surface 10a / another substrate surface and at least one second measuring bridge 12b and / or on a side of at least one second measuring bridge 12b facing away from the substrate 10 / another substrate.that by means of the at least one further soft magnetic shielding element a magnetic field component oriented along the second sensing direction is attenuated. Alternatively or additionally, the at least one further soft magnetic shielding element can also be arranged between the substrate surface 10a / further substrate surface and at least one third measuring bridge 12c and / or on a side of at least one third measuring bridge 12c facing away from the substrate 10 / further substrate, such that by means of the at least one further soft magnetic shielding element an attenuation of the magnetic field component oriented along the third sensing direction is effected.

[0069] The second / third range of values ​​can therefore extend from a minimum limit of less than or equal to 10 mT (millitesla) to a maximum limit of greater than or equal to 10 mT (millitesla). Preferably, the second / third range of values ​​extends from a minimum limit of less than or equal to -15 mT (millitesla) to a maximum limit of greater than or equal to 15 mT (millitesla). In particular, the second / third value range can extend from a minimum limit less than or equal to -20 mT (millitesla) to a maximum limit greater than or equal to 20 mT (millitesla), specifically from a minimum limit less than or equal to -25 mT (millitesla) to a maximum limit greater than or equal to 25 mT (millitesla), also from a minimum limit less than or equal to -50 mT (millitesla) to a maximum limit greater than or equal to 50 mT (millitesla), advantageously from a minimum limit less than or equal to -100 mT. R. 411380

[0070] - 16 -

[0071] (Millitesla) up to a maximum limit greater than or equal to 100 mT (Millitesla), preferably from a minimum limit less than or equal to -250 mT (Millitesla) up to a maximum limit greater than or equal to 250 mT (Millitesla), preferably from a minimum limit less than or equal to -500 mT (Millitesla) up to a maximum limit greater than or equal to 500 mT (Millitesla).

[0072] It should be noted that the materials in which the components of the magnetic sensor device described above are embedded must be non-magnetic. A respective intermediate volume between the at least one soft magnetic shielding element 26a and 26b and the at least one adjacent measuring bridge 12a, 12b and 12c or the at least one adjacent flux deflection structure 30 is preferably filled with at least one (not shown) electrically insulating, non-magnetic material. Similarly, it is also advantageous if an intermediate volume between the at least one first measuring bridge 12a and the at least one adjacent flux deflection structure 30 is filled with at least one (not shown) electrically insulating, non-magnetic material. For the sake of clarity, the top and bottom electrodes, via which the magnetoresistive elements 14a, 14b and 14c are electrically contacted, have been omitted from Fig.1a and 1b are waived.

[0073] Figs. 2a and 2b show schematic representations of a second embodiment of the magnetic sensor device.

[0074] In contrast to the embodiment described above, in the magnetic sensor device of Figures 2a and 2b, the at least one flux deflection structure 30 is formed as part of the at least one soft magnetic shielding element 26a and 26b on a side of the respective soft magnetic shielding element 26a and 26b that is oriented towards at least one first measuring bridge 12a. In this case as well, the conversion factor can typically be in the range between 0.001 and 0.4. The formation of the at least one flux deflection structure 30 as part of the at least one soft magnetic shielding element 26a and 26b also has no / hardly any R. 411380

[0075] - 17 - an influence on the comparatively large first range of values ​​within which the first magnetic field strength can be measured by means of at least the first measuring bridge 12a.

[0076] In the magnetic sensor device of Figures 2a and 2b, the two functionalities of shielding at least one first measuring bridge 12a from magnetic interference field components oriented parallel to the substrate surface 10a, and of deflecting the magnetic field component oriented perpendicular to the substrate surface 10a into the first sensing direction, are thus realized by the same unit. This facilitates miniaturization of the magnetic sensor device of Figures 2a and 2b.

[0077] Regarding further features and properties of the magnetic sensor device of Figs. 2a and 2b and its advantages, reference is made to the preceding description of the embodiment of Figs. 1a and 1b.

[0078] Figs. 3a and 3b show schematic representations of a third embodiment of the magnetic sensor device.

[0079] The magnetic sensor device of Figures 3a and 3b differs from the embodiment of Figures 1a and 1b described above in that no vortices are formed in the free positions 16 of the first magnetoresistive elements 14a, the second magnetoresistive elements 14b, or the third magnetoresistive elements 14c. Instead, in at least one of the first magnetoresistive elements 14a, its free position 16 lies between a first hard magnetic region 34a (hard bias) and a second hard magnetic region 34b (hard bias).In particular, the respective first hard magnetic region 34a and the respective second hard magnetic region 34b can be arranged relative to the associated free layer / free magnetization layer 16 such that an axis intersecting the first hard magnetic region 34a, the second hard magnetic region 34b and the associated free layer / free magnetization layer 16 is aligned parallel to the substrate surface 10a. This can also be achieved by means of at least one R. 411380.

[0080] - 18 - By providing the first hard magnetic region 34a and at least one second hard magnetic region 34b, the suitability of the magnetic sensor device for high-field applications can be improved. In particular, this ensures a comparatively large first range of values ​​within which the first magnetic field strength can be measured using at least one first measuring bridge 12a.

[0081] Optionally, the (unshown) free position of at least one of the second magnetoresistive elements 14b and / or at least one of the third magnetoresistive elements 14c can lie between a first hard magnetic region 34a and a second hard magnetic region 34b. The second and / or third range of values, within which the second / third magnetic field strength can be measured by means of at least one second / third measuring bridge 12b and 12c, can thus be extended by means of the hard magnetic regions 34a and 34b.

[0082] Regarding further features and properties of the magnetic sensor device of Figs. 3a and 3b and its advantages, reference is made to the preceding description of the embodiment of Figs. 1a and 1b.

[0083] Figs. 4a and 4b show schematic representations of a fourth embodiment of the magnetic sensor device.

[0084] As illustrated in Figs. 4a and 4b, even when using hard magnetic areas 34a and 34b, the at least one flux deflection structure 30 can each be formed as part of the at least one soft magnetic shielding element 26a and 26b on a side of the respective soft magnetic shielding element 26a and 26b oriented towards at least one first measuring bridge 12a.

[0085] Regarding further features and properties of the magnetic sensor device of Figures 4a and 4b and its advantages, reference is made to the preceding description of the embodiment of Figures 1 to 3. R. 411380

[0086] - 19 -

[0087] The magnetic sensor devices described above can be used in particular for position sensors, especially for smartphone camera applications and joystick / game controller sensors. When used with a smartphone camera, a particular magnetic sensor device can be effectively employed for optical image stabilization, autofocus, and zoom.

[0088] It is expressly pointed out that all the magnetic sensor devices described above implement magnetic sensing technology in which measurements can be performed without wear. In addition, the use of magnetoresistive elements 14a, 14b and 14c for the sensing technology of the magnetic sensor devices described above advantageously avoids the conventional use of comparatively power-hungry Hall sensors.

[0089] In all the magnetic sensor devices described above, the second sensing direction is preferably oriented perpendicular to the first sensing direction and / or perpendicular to the third sensing direction. The magnetic sensor devices described above can optionally be used to detect magnetic field components in three mutually orthogonal spatial axes. The magnetic sensor devices thus implement an advantageous two- or three-axis sensor design.

[0090] Fig. 5 shows a flowchart to explain one embodiment of the manufacturing process for a magnetic sensor device.

[0091] All the magnetic sensor devices described above can be produced using the manufacturing process described below. However, the feasibility of this manufacturing process is not limited to the production of these magnetic sensor devices.

[0092] When carrying out the manufacturing process described here, at least one first measuring bridge with first R. 411380 is produced in a process step S1.

[0093] - 20 - magnetoresistive elements on and / or above a substrate surface are configured such that, during operation of the subsequent magnetic sensor device, a first measurement quantity with respect to a first magnetic field strength is determined by means of at least one first measuring bridge in a first sensing direction parallel to the substrate surface. As explained above, the first sensing direction is parallel to a respective first magnetization direction of the reference positions of the first magnetoresistive elements. The process step S1 also comprises either a sub-step S1a or a sub-step S1b. In sub-step S1a, at least one of the first magnetoresistive elements is configured in its free position with a magnetic vortex.Alternatively, in sub-step S1 b, the free position of at least one of the first magnetoresistive elements is arranged between a first hard magnetic region and a second hard magnetic region.

[0094] In process step S2, at least one soft magnetic shielding element is formed between the substrate surface and at least one first measuring bridge, or on a side of at least one first measuring bridge facing away from the substrate. This ensures that the advantages listed above are also realized in the magnetic sensor device produced by process steps S1 and S2.

Claims

R. 411380 - 21 - Claims 1. Magnetic sensor device comprising: a substrate (10) with a substrate surface (10a); at least one first measuring bridge (12a) arranged on and / or above the substrate surface (10a), each with first magnetoresistive elements (14a), wherein a first measured quantity (Z+, Z-) with respect to a first magnetic field strength can be determined by means of at least one first measuring bridge (12a) in a first sensing direction running parallel to the substrate surface (10a), which is parallel to a respective first magnetization direction (20a) of the reference positions (18) of the first magnetoresistive elements (14a); and at least one soft magnetic shielding element (26a, 26b) which is arranged between the substrate surface (10a) and at least one first measuring bridge (12a) and / or on a side of at least one first measuring bridge (12a) facing away from the substrate (10);characterized in that at least one of the first magnetoresistive elements (14a) has a magnetic vortex (28) in its free position (16) or in the case of at least one of the first magnetoresistive elements (14a) whose free position (16) is located between a first hard magnetic area (34a) and a second hard magnetic area (34b); R. 411380 - 22 - 2. Magnetic sensor device according to claim 1, wherein the first magnetic field strength as the first measured quantity (Z+, Z-) within a structurally defined first value range can be determined by means of at least one first measuring bridge (12a), and wherein the first value range extends from a minimum limit value less than or equal to -10 mT to a maximum limit value greater than or equal to 10 mT.

3. Magnetic sensor device according to claim 2, wherein the first value range extends from a minimum limit value less than or equal to -15 mT to a maximum limit value greater than or equal to 15 mT.

4. Magnetic sensor device according to one of the preceding claims, wherein the magnetic sensor device comprises at least one flux deflection structure (30) by means of which a magnetic field component extending perpendicular to the substrate surface (10a) can be deflected into the first sensing direction.

5. Magnetic sensor device according to claim 4, wherein the at least one flux deflection structure (30) is formed as part of the at least one soft magnetic shielding element (26a, 26b) on a side of the respective soft magnetic shielding element (26b) oriented towards at least one first measuring bridge (12a).

6. Magnetic sensor device according to one of the preceding claims, wherein the magnetic sensor device comprises at least one second measuring bridge (12b) each with second magnetoresistive elements (14b), wherein at least one second measuring bridge (12b) is arranged on and / or above the substrate surface (10a) or a further substrate surface of a further substrate, and wherein, by means of at least one second measuring bridge (12b), a second measurement quantity (X+, X-) with respect to a second magnetic field strength in a second sensing direction, which is parallel to the substrate surface (10a) or the further substrate surface and parallel to a respective second R. 411380 - 23 - The magnetization direction (20b) of the reference positions of the second magnetoresistive elements (14b) can be determined.

7. Magnetic sensor device according to one of the preceding claims, wherein the magnetic sensor device comprises at least one third measuring bridge (12c) each with third magnetoresistive elements (14c), wherein at least one third measuring bridge (12c) is arranged on and / or above the substrate surface (10a) or the further substrate surface, and wherein a third measured quantity (Y+, Y-) with respect to a third magnetic field strength in a third sensing direction, which is parallel to the substrate surface (10a) or the further substrate surface and parallel to a respective third magnetization direction (20c) of the reference positions of the third magnetoresistive elements (14c), can be determined by means of at least one third measuring bridge (12c).

8. Magnetic sensor device according to claim 6 or 7, wherein at least one of the second magnetoresistive elements (14b) and / or at least one of the third magnetoresistive elements (14c) has a magnetic vortex (28) in its free position.

9. Magnetic sensor device according to claim 6 or 7, wherein in at least one of the second magnetoresistive elements (14b) and / or in at least one of the third magnetoresistive elements (14c) its free position is located between a first hard magnetic area (34a) and a second hard magnetic area (34b).

10. Magnetic sensor device according to one of claims 6 to 8, wherein the second sensing direction is oriented perpendicular to the first sensing direction and / or perpendicular to the third sensing direction.

11. Magnetic sensor device according to one of the preceding claims, wherein the first magnetoresistive elements (14a), the second R. 411380 - 24 - magnetoresistive elements (14b) and / or the third magnetoresistive elements (14c) are at least one TM R element and / or at least one GMR element.

12. Manufacturing process for a magnetic sensor device comprising the following steps: Forming at least one first measuring bridge (12c) with first magnetoresistive elements (14a) on and / or above a substrate surface (10a) of a substrate (10) such that, during operation of the subsequent magnetic sensor device, a first measured quantity (Z+, Z-) with respect to a first magnetic field strength is determined by means of at least one first measuring bridge (12a) in a first sensing direction running parallel to the substrate surface (10a), which is parallel to a respective first magnetization direction (20a) of the reference positions (18) of the first magnetoresistive elements (14a) (S1); and Forming at least one soft magnetic shielding element (26a, 26b) between the substrate surface (10a) and at least one first measuring bridge (12a) or on a side of at least one first measuring bridge (12a) facing away from the substrate (10); characterized in that at least one of the first magnetoresistive elements (14a) is formed in its free position (16) with a magnetic vortex (28) (S1 a) or in the case of at least one of the first magnetoresistive elements (14a) whose free position (16) is arranged between each first hard magnetic area (34a) and each second hard magnetic area (34b) (S1 b).

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