Magnetic sensor structures, devices and systems

Abstract

The invention discloses a magnetic sensor structure, device and system. A sensor device comprising at least one integrated magnetic sensor structure, the sensor device comprising: a semiconductor substrate; a magnetic flux concentrator (IMC) disposed on top of the semiconductor substrate, the IMC having a predefined shape with an elongated portion, the elongated portion extending in a first direction (X) parallel to the substrate; a horizontal Hall element (H2), the horizontal Hall element (H2) being positioned below the center of the IMC; processing circuitry connected to said horizontal Hall element (H2) and configured for providing a signal or value indicative of at least one magnetic field gradient (dBx / dx) or a signal or value derived therefrom (e.g., a current value).

Description

Technical Field

[0001] The present invention relates generally to the field of magnetic sensor devices and systems, and more particularly to magnetic sensor structures or devices for measuring magnetic field gradients. Background Art

[0002] Magnetic sensor devices comprising a semiconductor substrate and at least one horizontal Hall element are known in the art. They are used, for example, in linear position sensor devices, angular position sensor devices, current sensor devices, presence detectors, proximity detectors, etc.

[0003] As is well known, horizontal Hall elements can be used to measure magnetic field components oriented perpendicular to the semiconductor substrate (e.g., Bz), while vertical Hall elements and magnetoresistive (MR) elements (e.g., GMR, XMR, AMR) can measure magnetic field components parallel to the semiconductor substrate (e.g., Bx, By).

[0004] It is known that a magnetic sensor structure including an integrated magnetic flux concentrator (IMC) having a circular shape and including two horizontal Hall elements located near the periphery of the IMC and spaced 180° apart can be used to measure an in-plane component (e.g., a Bx component parallel to the substrate) and an out-of-plane component (e.g., a Bz component perpendicular to the substrate) of a magnetic field, for example, as illustrated in the figure numbered 6A of EP3650816 (A1).

[0005] A current sensor system typically includes a magnetic sensor device and an electrical conductor, such as an integrated conductor or an external conductor (such as a bus bar). By measuring the magnetic field generated by the current flowing through the conductor, the current can be determined in a contactless manner.

[0006] There are many variations of magnetic sensor structures and devices and systems that address one or more of the following requirements: use simple or inexpensive magnetic structures, use simple or inexpensive sensor devices, be able to measure over a relatively large range, be able to measure with high accuracy, require only simple algorithms, be able to measure at high speeds, be highly robust to positioning errors, be highly robust to external interference fields, provide redundancy, be able to detect errors, be able to detect and correct errors, have a good signal-to-noise ratio (SNR), etc. Two or more of these requirements often conflict with each other, so trade-offs need to be made.

[0007] There is always room for improvement or substitution. Summary of the invention

[0008] An object of an embodiment of the present invention is to provide a magnetic sensor structure or a magnetic sensor arrangement which can be used to measure a magnetic field gradient.

[0009] An object of an embodiment of the present invention is also to provide a magnetic sensor device (eg, a semiconductor wafer, a semiconductor die, a packaged device (also referred to as a “chip”) including at least one semiconductor die) including such a magnetic sensor structure.

[0010] An embodiment of the present invention also aims to provide a magnetic sensor system, which is, for example: a current sensor system comprising such a magnetic sensor device (for example, in the form of an integrated chip) and an electrical conductor; or a position sensor system comprising such a magnetic sensor device and a permanent magnet movable relative to the sensor device; or a torque sensor system comprising such a magnetic sensor device and at least one magnet; and so on.

[0011] It is an object of embodiments of the present invention to provide magnetic sensor structures, devices and systems that are able to measure magnetic field gradients with improved accuracy (eg, that are highly insensitive to external interfering fields).

[0012] Certain embodiments of the present invention aim to provide magnetic sensor structures, devices and systems that are capable of measuring magnetic field gradients using simple structures (eg, an IMC and one or two or three or more horizontal Hall elements).

[0013] It is an object of embodiments of the present invention to provide magnetic sensor structures, devices and systems suitable for use in robotic and / or industrial and / or automotive environments.

[0014] These and other objectives are achieved by embodiments of the present invention.

[0015] According to a first aspect, the present invention provides a sensor device (e.g., an integrated semiconductor device, also referred to as a "chip"), comprising: at least one (e.g., only one or two) integrated magnetic sensor structures, comprising: a semiconductor substrate (e.g., a silicon substrate); a magnetic flux concentrator (IMC) disposed on top of the semiconductor substrate, the magnetic flux concentrator (IMC) having a predefined shape with an elongated portion extending in a first direction (X) parallel to the semiconductor substrate; a horizontal Hall element (e.g., H2) disposed in or on the substrate and positioned below the center of the IMC; a processing circuit connected to the horizontal Hall element (e.g., H2) and configured to provide a signal or value indicating at least one magnetic field gradient (e.g., dBx / dx) of a magnetic field surrounding the at least one integrated magnetic sensor structure, or a signal or value derived therefrom (e.g., a current value, a linear or angular position value, a distance value).

[0016] The magnetic field gradient so measured is the gradient (expressed as dBx / dx) of the magnetic field component Bx oriented in the first direction, along the first direction.

[0017] "Positioned below the center" means that an imaginary line oriented perpendicular to the substrate and passing through the geometric center of the predefined shape passes through the horizontal Hall element.

[0018] The sensor device may include, for example, a single semiconductor substrate including a single “integrated magnetic sensor structure”, or may include two separate semiconductor substrates, each including a single “integrated magnetic sensor structure”, or may include a single semiconductor substrate including two “integrated magnetic sensor structures”.

[0019] The integrated magnetic sensor structure may include more than one horizontal Hall element, for example, two horizontal Hall elements positioned near the ends of the elongated IMC (e.g., Figure 1B H1 and H3), or horizontal Hall elements not located under the IMC (e.g. Figure 5B H6), or a horizontal Hall element also located below the IMC but relatively far from the center (e.g. Figure 6 H4), or two horizontal Hall elements located in the so-called "white area" (e.g. Figure 7 of H4 and H5).

[0020] A signal or value may be derived from at least one measured signal using a linear function of the one or more measured signals.

[0021] The horizontal Hall element may be embedded in a semiconductor substrate and may be located on the "top side" (also referred to as the "device side") of the semiconductor substrate. The IMC associated with the horizontal Hall element is preferably also located on the top side of the semiconductor substrate. Preferably, there is no IMC located on the back side of the semiconductor substrate.

[0022] If the semiconductor substrate includes more than one IMC on its top side (e.g. Fig.9A , Fig. 9B , Fig.10 ), the IMCs are preferably spaced apart by at least 200 μm, or at least 250 μm, or at least 300 μm, or at least 400 μm, or at least 500 μm, or at least 600 μm, or at least 700 μm, or at least 800 μm, or at least 900 μm, or at least 1000 μm.

[0023] The predefined shape is not a circle or a ring.

[0024] The semiconductor substrate may be a silicon substrate.

[0025] Preferably, the semiconductor substrate has an active surface, and the horizontal Hall element is implemented in said active surface, and the IMC is positioned on the active surface via at least one intermediate layer.The horizontal Hall element and the IMC are preferably located on the same side of the semiconductor substrate.

[0026] The IMC may have a constant thickness throughout its length.

[0027] The IMC may have a linear shape.

[0028] In an embodiment, the predefined shape is an integral beam shape having a predefined length L and a predefined width W. Preferably, the beam shape is a single solid piece of material without gaps.

[0029] In an embodiment, the elongated portion has an overall rectangular cross-section having a predefined length L and a predefined width W in a plane parallel to the substrate.

[0030] The horizontal Hall element may have a substantially square plate having a length and a width of 15 to 25 μm (eg, a length and a width of about 20 μm, or about 22 μm).

[0031] The width W of the IMC is preferably a value in the range from 10 μm to 200 μm. The width W of the IMC may be at least 20 μm, or at least 30 μm, or at least 40 μm, or at least 50 μm, or at least 75 μm (e.g., equal to about 100 μm ± 10%).

[0032] The length L of the IMC is preferably a value in the range of 250 μm to 1000 μm. The length L of the IMC may be at least 300 μm, or at least 400 μm, or at least 500 μm, or at least 600 μm, or at least 700 μm, or at least 800 μm, or at least 900 μm (e.g., equal to about 1000 μm ± 10%).

[0033] In an embodiment, the ratio of the length L to the width W (L / W) of the IMC is at least 3.0.

[0034] In an embodiment, a ratio of the length L to the width W (L / W) of the IMC is a value in a range from 3.0 to 20.0.

[0035] In an embodiment, a ratio of the length L to the width W (L / W) of the IMC is a value in a range from 4.0 to 10.0.

[0036] In an embodiment, a ratio of the length L to the width W (L / W) of the IMC is a value in a range from 5.0 to 10.0.

[0037] In an embodiment, a ratio of the length L to the width W (L / W) of the IMC is a value in a range from 6.0 to 10.0.

[0038] The magnetic flux concentrator (IMC) may have a thickness T in the range from 15 μm to 29 μm, or from 18 μm to 25 μm (eg, equal to 20±1 μm, or equal to about 22±1 μm).

[0039] In an embodiment, the sensor device includes only a single IMC, and only one horizontal Hall element is positioned below the IMC. Figure 5A and Figure 5B An example of such an embodiment is shown in FIG.

[0040] In an embodiment, the sensor device includes two magnetic flux concentrators and only one horizontal Hall element is positioned below the IMC. The sensor device may include a single semiconductor substrate including the two horizontal Hall elements and including two IMCs on top, or may include two separate semiconductor substrates, each with a single IMC, and at least one horizontal Hall element below the IMC. Fig.9A , Fig. 9B , Fig.10 An example of such an embodiment is shown in FIG.

[0041] In an embodiment, the IMC has an elongated shape extending over a predefined length L; and the integrated magnetic sensor structure further includes a second horizontal Hall element (e.g., H4) positioned below the IMC and spaced from the center of the IMC by a distance in the range from L*26% to L*40%, or a distance in the range from L*30% to L*36%, or a distance in the range of (L / 3)±7%, or a distance in the range of (L / 3)±5%, or a distance in the range of (L / 3)±3%. Positioning the second horizontal Hall element in the so-called "white spot" is advantageous because the signal obtained from this Hall element will be highly insensitive to the common mode value of Bx.

[0042] In an embodiment, the IMC has an elongated shape extending over a predefined length L; and the integrated magnetic sensor structure further includes a second horizontal Hall element and a third horizontal Hall element (e.g., H1 and H3, or H4 and H5), the second horizontal Hall element and the third horizontal Hall element (e.g., H1 and H3, or H4 and H5) are positioned below the IMC and arranged such that the first horizontal Hall element is positioned in the middle between the second horizontal Hall element and the third horizontal Hall element. An example of this embodiment is Figures 1A to 3 , Figure 7 , Fig. 8A and Figure 8B is shown in the figure.

[0043] In an embodiment, the distance (eg, d12 ) between the center of the IMC and the second and third horizontal Hall elements (eg, H1 , H3 ) is at least L*41%.

[0044] Or simply put, in this embodiment, one horizontal Hall element (e.g., H2) is located near the center of the IMC, and two horizontal Hall elements (e.g., H1, H3) are located near the ends of the IMC. Figure 1B , Figure 2 Part (a) of Fig. 8A , Figure 8B The main advantage of this embodiment is that it can accurately measure the gradient of Bx along the X direction (dBx / dx) using only three horizontal Hall elements and a single IMC.

[0045] In an embodiment, the distance is a value in the range from L*41% to L*60%.

[0046] In an embodiment, the distance is a value in the range from L*41% to (L / 2)+(s / 2), where "s" is the length or width of a (square) Hall element.

[0047] In an embodiment, the distance is a value in the range from L*41% to L*50%, ie the IMC overlaps at least 50% of the Hall element.

[0048] In an embodiment, the distance is a value in the range from L*41% to (L / 2)-(s / 2), ie the IMC completely overlaps the Hall element.

[0049] In an embodiment, the distance (e.g., d7a, d7b) between the center of the IMC and the second horizontal Hall element and the third horizontal Hall element (e.g., H4, H5) is a distance in the range from L*26% to L*40%, or a distance in the range from L*30% to L*36%, or a distance in the range of (L / 3)±7%, or a distance in the range of (L / 3)±5%, or a distance in the range of (L / 3)±3%. Figure 7 An example of this embodiment is shown in FIG.

[0050] Or simply stated, in this embodiment, one horizontal Hall element is located near the center of the IMC, and two horizontal Hall elements are located on opposite sides of the center at distances d7a, d7b from the center equal to about (L / 3).

[0051] In an embodiment, the sensor device is a current sensor device configured to measure magnetic field characteristics (e.g., a magnetic field gradient) generated by a current flowing through a portion of an electrical conductor; wherein the processing circuit is configured to provide a signal or value indicative of the current based on at least one signal obtained from at least one horizontal Hall element, for example as a linear function of the signal obtained from the horizontal Hall element.

[0052] The current sensor device may further include the above-mentioned processing circuit, which is connected to the one or more horizontal Hall elements and is configured to determine the current flowing through the electrical conductor portion arranged near the at least one sensor structure. The electrical conductor portion may be integrated inside the current sensor device or may be located outside the current sensor device.

[0053] In an embodiment, the current sensor device further comprises at least one temperature sensor, for example arranged near the center of the IMC, and the processing circuit may be further configured for temperature correction of the signal obtained from the at least one horizontal Hall element.

[0054] In an embodiment, the current sensor device comprises a single substrate including a single integrated magnetic concentrator having, for example, Fig. 8A or Figure 8B At least one (eg, single, two, three, four, or five) horizontal Hall plates are arranged as illustrated in FIG.

[0055] In an embodiment, the current sensor device includes a single substrate including at least two IMCs, each IMC having at least one (e.g., single, two, three, four, or five) horizontal Hall plates. The two integrated IMCs may be oriented in parallel directions (e.g., as Fig.9A ), or may be oriented in orthogonal directions (e.g., as shown in Fig.10 ).

[0056] In an embodiment, the current sensor device comprises at least two semiconductor substrates, each substrate comprising a single IMC, each IMC having at least one (e.g., single, two, three, four, or five) horizontal Hall plates, e.g., as Fig. 9B As shown in the figure.

[0057] In an embodiment, a current sensor device includes at least two semiconductor substrates, each substrate including at least two IMCs, each IMC having at least one (eg, single, two, three, four, or five) horizontal Hall plates.

[0058] In an embodiment, a current sensor device includes an integrated magnetic sensor structure and a processing circuit, the integrated magnetic sensor structure including an IMC and three horizontal Hall elements (e.g., H1, H2, H3), the processing circuit being configured to determine the current according to a formula I=K*(h1+h3-h2), or according to a formula I=K*(h1+h3-2*h2), where K is a predefined constant, h1 and h3 are signals obtained from a second horizontal Hall element and a third horizontal Hall element (H1, H3) located near the ends of the IMC, and h2 is a signal obtained from a horizontal Hall element (H2) located near the center of the IMC.

[0059] In an embodiment, the current sensor device includes a first integrated magnetic sensor structure and a second integrated magnetic sensor structure, the first integrated magnetic sensor structure including a first IMC and a first horizontal Hall element (e.g., H2a) located below the center of the first IMC, and the second integrated magnetic sensor structure including a second IMC and a second horizontal Hall element (e.g., H2b) located below the center of the second IMC; and the processing circuit is configured to determine the current according to the formula I=K*(h2a-h2b), where K is a predefined constant, h2a is a signal obtained from the first horizontal Hall element (e.g., H2a), and h2b is a signal obtained from the second horizontal Hall element (e.g., H2b).

[0060] In an embodiment, the current sensor has a first IMC and a second IMC, and the first IMC and the second IMC are oriented in parallel and are located on a single virtual line (X), for example, as Fig.9A , Fig. 9B As shown in the figure.

[0061] In an embodiment, the current sensor has a first IMC and a second IMC, and the first IMC and the second IMC are oriented in parallel and are spaced apart so as to define a virtual rectangle.

[0062] In an embodiment, the current sensor has a first IMC and a second IMC, and the first IMC and the second IMC are oriented perpendicular to each other and are spaced apart from each other, for example, as shown in FIG. Fig.10 As shown in the figure.

[0063] The present invention also provides a current sensor system, comprising the current sensor device as described above; and an electrical conductor portion (eg, a bus bar) extending in a predefined direction (eg, Y).

[0064] In an embodiment, the integrated magnetic sensor structure comprises three horizontal Hall elements arranged below the IMC, and the IMC is oriented perpendicular to said predefined direction (of the electrical conductor portion).

[0065] Preferably, the current sensor device is arranged relative to the conductor part so that the projection of the central horizontal Hall plate (H2) is offset from a central position on the conductor part, or is above the conductor part, on the edge, or outside the conductor part.

[0066] In a particular embodiment, the current sensor device is positioned relative to the conductor portion such that (i) a projection of the central horizontal Hall plate (H2) is close to a lateral edge of the conductor portion, (ii) the second horizontal Hall element (H3) is located substantially halfway between the lateral edges of the conductor portion, and the third horizontal Hall element (H1) is located at a non-zero lateral distance from the conductor portion.

[0067] In an embodiment, the current sensor device includes a first IMC and a first horizontal Hall element arranged below the center of the first IMC, and a second IMC and a second horizontal Hall element arranged below the center of the second IMC, the current sensor device being arranged in one of the following ways:

[0068] i) wherein the first IMC and the second IMC are located on a single imaginary line (e.g., X), and the current sensor device is oriented such that the imaginary line is oriented perpendicular to said predefined direction (Y);

[0069] ii) wherein the first IMC and the second IMC are oriented parallel to a predefined direction (e.g., Y) and are spaced apart so as to define a virtual rectangle; and wherein the electrical conductor portion has a first transverse cutout and a second transverse cutout; and wherein the first horizontal Hall element (H2a) is positioned above the first cutout and the second horizontal Hall element (H2b) is positioned above the second cutout;

[0070] iii) wherein the electrical conductor portion has a U-shape comprising two legs interconnected by a bridge; and wherein the first IMC is oriented perpendicular to the bridge and the first horizontal Hall element (e.g., H2a) is positioned near an outer edge (e.g., e1) of the bridge; and wherein the second IMC is oriented parallel to the bridge and the second horizontal Hall element (e.g., H2b) is positioned between the two legs near an inner edge (e.g., e2) of the bridge, e.g., as Fig.10 As shown in the figure.

[0071] According to another aspect, the invention also provides a distance sensor device or proximity sensor device comprising at least one integrated magnetic sensor structure for measuring a magnetic field gradient signal of a magnetic field, for example generated by a magnet movable relative to the sensor device. The gradient signal indicates the distance between the sensor device and the magnet.

[0072] According to another aspect, the invention also provides a distance sensor system or a proximity sensor system comprising such a sensor device and a magnet or a magnetic structure.

[0073] According to another aspect, the present invention also provides a position sensor device, which includes at least two integrated magnetic sensor structures for measuring a first magnetic field gradient signal and a second magnetic field gradient signal of a magnetic field generated, for example, by a magnet that can move (e.g., rotate) relative to the sensor device. The first gradient signal and the second gradient signal can be sinusoidal signals with substantially equal amplitudes and a phase shift of substantially 90°. The sensor device can be further configured to determine a position (e.g., a linear position or an angular position) based on a ratio of the first magnetic field gradient to the second magnetic field gradient.

[0074] According to another aspect, the invention also provides a position sensor system (eg an angular position sensor system or a linear position system) comprising such a sensor device and a magnet or a magnetic structure.

[0075] Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features from the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not just as explicitly set out in the claims.

[0076] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1A shows a side view of a magnetic sensor structure according to an embodiment of the present invention, and Figure 1B A top view of a magnetic sensor structure according to an embodiment of the present invention is shown, the magnetic sensor structure including an IMC and three horizontal Hall elements.

[0078] Figure 2 Parts (a) to (g) of Figure 1A Schematic representation of the sensor structure, showing that the three horizontal Hall elements measure different parts of the magnetic field surrounding the structure.

[0079] Figure 3 Shows the application Figure 1A and Figure 2 A set of formulas for the sensor structure of part (a).

[0080] Figure 4Parts (a) to (d) of FIG. 1 show simulation results illustrating how the amplitude of a signal that can be measured by a horizontal Hall element located below the IMC varies according to the position along the X-axis when a magnetic field having a pure gradient dBx / dx of 25 mT / mm is applied.

[0081] FIG. 5A to FIG. 5D A magnetic sensor structure according to an embodiment of the present invention is shown. Figure 5A A magnetic sensor structure including an elongated IMC and a horizontal Hall element positioned below the center of the IMC is shown. Figure 5B Shows Figure 5A A variation of the present invention further includes a second horizontal Hall element not located below the IMC. Figure 5C Shows Figure 5A A variation of the IMC wherein the IMC has radiused ends or rounded ends. Figure 5D Shows Figure 5A A variation of the IMC in which the IMC has tapered ends (e.g., triangular ends).

[0082] Figure 6 An illustrative example of a magnetic sensor structure including an elongated IMC and a first horizontal Hall element positioned below the center of the IMC and including a second Hall element located below the IMC, off-center, is shown as another embodiment of the present invention.

[0083] Figure 7 An illustrative example of a magnetic sensor structure as another embodiment of the present invention is shown, which includes an elongated IMC and a first horizontal Hall element positioned below the center of the IMC, and includes a second horizontal Hall element and a third horizontal Hall element located below the IMC, both of which are off-center.

[0084] Fig. 8A and Figure 8B Shown include Figure 1A or Figure 2 Two illustrative examples of current sensor systems of a magnetic sensor structure illustrated in part (a) of the present invention, the magnetic sensor structure comprising an IMC and three horizontal Hall elements, one horizontal Hall element located at the center of the IMC and two horizontal Hall elements located near the outer ends of the IMC.

[0085] Fig.9A and Fig. 9B Two illustrative examples of current sensor systems are shown, which include a straight bus bar and two magnetic sensor structures located on opposite sides of the bus bar and oriented in a direction perpendicular to the direction of current flow. The magnetic sensor structures each include an IMC and a horizontal Hall element located in the middle of the IMC, such as Figure 5AThe two IMCs may have the same shape and / or size.

[0086] Fig.10 The diagram shows a U-shaped bus bar and two Figure 5A An illustrative example of a current sensor system with a magnetic sensor structure as illustrated in FIG.

[0087] Fig.11 A high-level block diagram of a magnetic sensor device including one or more of the sensor structures described above is shown.

[0088] These drawings are only schematic and non-limiting. In the drawings, for illustrative purposes, the size of some of the elements may be exaggerated and not drawn to scale. Any reference numerals in the claims should not be construed as limiting the scope. In different drawings, the same reference numerals refer to the same or similar elements. DETAILED DESCRIPTION

[0089] The present invention will be described with respect to specific embodiments and with reference to certain drawings, but the invention is not limited thereto but only by the claims. The drawings described are only schematic and non-limiting. In the drawings, for illustrative purposes, the size of some of the elements may be exaggerated and not drawn to scale. The dimensions and relative dimensions do not correspond to actual reductions in the practice of the invention.

[0090] Furthermore, the terms first, second, etc. in the specification and in the claims are used to distinguish between similar elements and are not necessarily used to describe a sequence in time, space, in ranking, or in any other manner. It should be understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments of the invention described herein are capable of operation in a sequence different from that described or illustrated herein.

[0091] Furthermore, the terms top, bottom, etc. in the description and claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in orientations other than those described or illustrated herein.

[0092] It should be noted that the term "comprising" used in the claims should not be interpreted as being limited to the means listed thereafter; it does not exclude other elements or steps. Thus, the term should be interpreted as specifying the presence of the stated features, integers, steps or components as mentioned, but does not exclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of component A and component B. It means that for the present invention, the only relevant components of the device are A and B.

[0093] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily all refer to the same embodiment, but may. Furthermore, in one or more embodiments, as would be apparent to one of ordinary skill in the art from this disclosure, the particular features, structures, or characteristics may be combined in any suitable manner.

[0094] Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects, the various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than those explicitly recited in each claim. On the contrary, as reflected in the appended claims, the inventive aspects lie in fewer features than all of the features of a single preceding disclosed embodiment. Thus, the claims appended to the Detailed Description are hereby expressly incorporated into the Detailed Description, with each claim itself representing a separate embodiment of the invention.

[0095] In addition, although some embodiments described herein include some features included in other embodiments but do not include other features included in these other embodiments, the combination of features of different embodiments is intended to fall within the scope of the present invention and form different embodiments as will be understood by those skilled in the art. For example, in the appended claims, any of the claimed embodiments may be used in any combination.

[0096] In the description provided herein, numerous specific details are set forth. However, it should be understood that embodiments of the present invention may be implemented without these specific details. In other examples, well-known methods, structures, and techniques are not shown in detail to avoid confusion in understanding this description.

[0097] In this document, IMC stands for "Integrated Flux Concentrator".

[0098] In this document, the symbol ">>" means "much greater than".

[0099] In this document, the symbol “<<” means “much less than”.

[0100] In this document, the symbol "≈" means "approximately equal to."

[0101] In this document, the terms "horizontal Hall element" and "horizontal Hall plate" are used as synonyms.

[0102] In this document, the expression "magnetic sensor structure" or "magnetic sensor arrangement" may refer to an IMC and one or more horizontal Hall elements arranged below the IMC or arranged near the periphery of the IMC (eg, at a distance of at most 50 μm).

[0103] In this document, unless explicitly mentioned otherwise, the term "magnetic sensor device" refers to a packaged or unpackaged semiconductor device comprising at least one such "magnetic sensor structure". The sensor device may be included in a package (also referred to as a "chip"), but that is not absolutely necessary. The sensor device preferably comprises a semiconductor substrate.

[0104] In this document, the expressions "in-plane component of the magnetic field vector" and "projection of the magnetic field vector in the sensor plane" mean the same thing. If the sensor device is or comprises a substrate, this also means "the magnetic field component parallel to the substrate".

[0105] In this document, the expressions “out-of-plane component of a vector” and “Z-component of a vector” and “projection of the vector onto an axis perpendicular to the sensor plane” mean the same thing.

[0106] Embodiments of the present invention are typically described using an orthogonal coordinate system fixed to the sensor device and having three axes X, Y, Z, wherein the X-axis and the Y-axis are parallel to the substrate and the Z-axis is perpendicular to the substrate.

[0107] In embodiments of the present invention, the X-axis is preferably oriented in the longitudinal direction of the elongated IMC.

[0108] In this document, the expressions "spatial derivative" or "derivative" or "spatial gradient" or "gradient" are used as synonyms. In the prior art, the gradient of a certain magnetic field component "along the X direction" (e.g., Bz) is usually determined as the difference between two such component values ​​(e.g., Bz1, Bz2) measured at two positions spaced apart in the X direction. In theory, the gradient is calculated as the difference between the two values ​​divided by the distance "dx" between the sensor positions, but in practice, the division by "dx" is often omitted because the measured signal needs to be scaled anyway. The present invention will measure the magnetic field gradient in a different way, but also make an abstraction of the scaling factor.

[0109] In this application, the horizontal Hall plates are generally referred to as H1, H2, etc. The signals from these horizontal Hall plates are generally referred to as h1, h2, etc.

[0110] The present invention relates to a magnetic sensor structure or a magnetic sensor arrangement for measuring a magnetic field gradient, more particularly for measuring an "in-plane magnetic field gradient" (eg dBx / dx).

[0111] The invention also relates to a magnetic sensor system (eg a current sensor system, a position sensor system, a torque sensor system) comprising one or more such magnetic sensor structures.

[0112] Figure 1A shows a side view of the magnetic sensor device 110, and Figure 1B A top view of a magnetic sensor device 110 is shown, and the magnetic sensor device 110 includes a semiconductor substrate 111 and a magnetic sensor structure.

[0113] Figure 1A The magnetic sensor structure includes an integrated magnetic flux concentrator (IMC) 113 and three horizontal Hall elements H1, H2, H3, but the present invention is not limited thereto, and other embodiments may have an IMC with only one horizontal Hall element (see, for example Figure 5A ), or an IMC with two horizontal Hall elements located below the IMC (see e.g. Figure 6 ).

[0114] In accordance with the basic principles of the present invention, one of the horizontal Hall elements (generally labeled H2) is positioned at the center of the IMC for reasons that will become clear further on.

[0115] The IMC has a predefined shape with an elongated portion, for example a portion having a shape with a rectangular cross section (as seen from above the substrate). The ends of the rectangular portion may have right angles, but this is not absolutely necessary, see e.g. Figure 5C , where the IMC has rounded ends, and see e.g. Figure 5D, where the IMC has a tapered end (e.g., a triangular end).

[0116] exist Figure 1A In the example of FIG. 1 , two other horizontal Hall elements H1 , H3 are located near the ends of the elongated IMC, but this is not absolutely necessary, e.g. Figure 7 , where two other horizontal Hall elements H1 , H3 are positioned on opposite sides of the central element H2 , but at a distance not necessarily equal to half the length L of the elongated structure.

[0117] exist Figure 1B , the centers of the Hall elements H1 and H3 are preferably offset from the center of the IMC by a distance d12 in the range from L*41% to L*50%. This means that the Hall elements H1 and H3 do not need to be completely below the IMC (or in other words, the IMC does not need to completely overlap the Hall elements). In some embodiments, the Hall elements H1 to H3 are completely below the IMC. In this case, the distance d12 is less than (L / 2)-(s / 2). In some embodiments, the IMC partially overlaps the Hall plate, for example, by 1% to 50% of the area of ​​the Hall elements.

[0118] Return to reference Figure 1A and Figure 1B , the IMC may have a thickness T in a range from 15 μm to 29 μm, or from 18 μm to 25 μm (eg, equal to 20±1 μm, or equal to approximately 22±1 μm).

[0119] The IMC may have a length L in the range from 60 μm to 1000 μm, or from 100 μm to 1000 μm, or from 200 μm to 1000 μm, or from 400 μm to 800 μm.

[0120] The IMC may have a width W in a range from 24 μm to 200 μm, or from 30 μm to 175 μm, or from 40 μm to 150 μm (eg, equal to about 100 μm).

[0121] The IMC layer may contain a soft magnetic material, for example, consisting of or including a Fe-Ni alloy or a Fe-Co alloy.

[0122] In preferred embodiments, the length to width ratio L / W may be a value in the range from 3.0 to 20.0, for example, at least 4.0, or at least 6.0, or at least 8.0, or at least 10.0; and at most 20.0, or at most 18.0, or at most 15.0.

[0123] The horizontal Hall element may have a primarily square plate having a length and a width "s" of about 15 μm to about 25 μm. Preferably, the width W of the IMC is equal to or greater than the width "s" of the horizontal Hall element, for example, at least 20% greater, or at least 50% greater than the width of the horizontal Hall plate.

[0124] The horizontal Hall element is preferably implemented in the active surface of the semiconductor substrate 111. The IMC 113 and the horizontal Hall element are preferably separated by an insulating layer 112, for example, by a polymer layer, for example, by a polyimide layer. Methods for producing a semiconductor substrate 111 including a horizontal Hall element, as well as methods for depositing the insulating layer 112, and methods for depositing a layer of magnetic material for the IMC 113, for example by sputtering or by electroplating or both, are known in the art and therefore do not need to be explained in more detail here.

[0125] Figure 2 Part (a) shows Figure 1A The magnetic sensor structure 205 includes an IMC 213 having an elongated shape or an elongated portion (eg, a rectangular portion), and at least one horizontal Hall element H2 located in the middle below the IMC 213, but Figure 1A and Figure 2 In the example of part (a), two horizontal Hall elements H1 and H3 located near the ends of the elongated shape are also included.

[0126] It is known that a magnetic sensor structure comprising a circular IMC and two horizontal Hall elements located near the periphery of the IMC and spaced 180° apart can be used to measure a magnetic field component Bx oriented parallel to the substrate (e.g., by subtracting and scaling the signals obtained from the Hall elements) and a magnetic field component Bz oriented perpendicular to the substrate (e.g., by adding and scaling the signals). It is also known that a device comprising two circular IMCs spaced apart along the X axis (each IMC having two horizontal Hall elements located on the X axis, thus a total of four horizontal Hall elements) can be used to determine the magnetic field gradient dBx / dx and the magnetic field gradient dBz / dx, for example according to EP3650816 (A1).

[0127] However, the inventors of the present invention surprisingly found that Figure 2 The signal h2 obtained by the horizontal Hall element H2 below the center (or middle) of the elongated IMC 213 of part (a) can be used to determine the magnetic field gradient dBx / dx at position x2 at the center of the IMC, as will be explained below. To the best of the inventors' knowledge, this effect is unknown in the prior art.

[0128] Although the inventors do not wish to be bound by any theory, Figure 2Parts (b) to (g) of FIG. 214 illustrate how certain aspects of the magnetic field surrounding the IMC 213 can be measured by horizontal Hall elements H1, H2, and H3. In the figure, it is assumed that the magnetic field surrounding the IMC can be approximated by a common-mode portion and a differential portion (or gradient portion). The magnetic sensor structure is insensitive to magnetic fields oriented in the Y direction (perpendicular to the page), but is sensitive to magnetic fields oriented in the X direction and / or the Z direction.

[0129] Figure 2 Part (b) of FIG. 4 illustrates how a magnetic field oriented in the X direction may be decomposed into a common mode portion Bx_cm and a gradient portion diff_Bx.

[0130] Figure 2 Part (c) shows how the common mode part can be sensed by the Hall sensors H1, H2, H3, namely as signals: h1=Gx*Bx_cm; h2=0; h3=-Gx*Bx_cm, respectively, where Gx is a first gain factor, i.e. a first predefined constant, which can be determined by simulation, during measurement or during a calibration test, and can optionally be stored in a non-volatile memory of the semiconductor device.

[0131] Figure 2 Part (d) shows how the differential portion can be sensed by the Hall elements H1 , H2 , H3 , namely as signals: h1 = Gx*diff_Bx; h2 = 2*Gx*diff_Bx; h3 = Gx*diff_Bx, respectively.

[0132] Figure 2 Part (e) of FIG. 5 illustrates how a magnetic field oriented in the Z direction may be decomposed into a common mode portion Bz_cm and a gradient portion diff_Bz.

[0133] Figure 2 Part (f) shows how the common mode part can be sensed by the Hall sensors H1, H2, H3, i.e. as a signal: h1 = Gz*Bz_cm; h2 = Gz*Bz_cm; h3 = Gz*Bz_cm, where Gz is a second gain factor, i.e. a second predefined constant, which can be determined by simulation, measurement, or during a calibration test, and can optionally be stored in a non-volatile memory of the semiconductor device.

[0134] Figure 2 Part (g) shows how the differential portion diff_Bz will be sensed by the Hall elements H1 , H2 , H3 , namely as signals: h1 = Gz*diff_Bz; h2 = 0; h3 = -Gz*diff_Bz.

[0135] Figure 3 Shows the application Figure 1A and Figure 2 A set of formulas for the sensor structure in part (a) of FIG. These formulas can be obtained by taking each of the signals h1, h2, and h3 as Figure 2 Part (c) of Figure 2 Part (d) of Figure 2 Part (f) and Figure 2 The parts shown in part (g) of are added, and are obtained by considering that Bx_cm corresponds to Bx, diff_Bx corresponds to dBx / dx, Bz_cm corresponds to Bz, and diff_Bz corresponds to dBz / dx.

[0136] Formula [4a] can be obtained by adding Formulas [1] and [3], and if the gradient term is small relative to the component term, Formula [4a] can be simplified to Formula [4b].

[0137] Formula [5] can be obtained by subtracting formula [4a] from 2*formula [2].

[0138] Formula [6a] can be obtained by subtracting Formulas [1] and [3], and if the gradient term is small relative to the component term, Formula [6a] can be simplified to Formula [6b].

[0139] It will be appreciated that the gradient (dBx / dx) can be calculated or estimated based on formula [2] and thereby calculated or estimated from the signal h2 that can be obtained from the horizontal Hall element H2 positioned in the middle of the IMC, for example, in the case where the value of Bz is zero or relatively small compared to the value of (dBx / dx), or if the value of Bz is otherwise measured and subtracted (see, for example Figure 5B , Fig.9A , Fig. 9B , Fig.10 ).

[0140] It will be appreciated that the gradient (dBx / dx) may also be calculated based on formula [5], which is applicable even if Bx≠0 and / or Bz≠0 and / or (dBz / dx)≠0.

[0141] Figure 4 Parts (a) to (d) of FIG. 1 show the Figure 1A and Figure 2 Results of simulations performed on the magnetic sensor structure with three horizontal Hall elements H1, H2, H3 illustrated in part (a) of FIG. 1 , where the applied magnetic field has no common mode value but a pure gradient dBx / dx of 25 mT / mm, and where the IMC is made of Fe-Ni alloy and has a thickness T of 20 μm and a width W of 100 μm for various lengths of the IMC. The following numerical results are obtained:

[0142] exist Figure 4 In part (a): L = 400 μm, (thus L / W = 4), |h2| = 3 mT, |h1| = |h3| = 5 mT.

[0143] exist Figure 4 In part (b): L = 600 μm, (thus L / W = 6), |h2| = 6 mT, |h1| = |h3| = 11.5 mT.

[0144] exist Figure 4 In part (c): L = 800 μm, (thus L / W = 8), |h2| = 10 mT, |h1| = |h3| = 22 mT.

[0145] exist Figure 4 In part (d): L = 1000 μm, (thus L / W = 10), |h2| = 12 mT, |h1| = |h3| = 28 mT.

[0146] For illustrative purposes, two pictures are shown in each case: a grayscale picture on the left, and a dithered picture on the right.

[0147] Quite surprisingly, these simulations also show that there are two positions indicated by X4 and X5 (also referred to herein as "white areas") where the horizontal Hall element (if placed at this position / positions) will be insensitive to (Bx) and to (dBx / dx), but only sensitive to (Bz) and to (dBz / dx). To the best of the inventors' knowledge, this effect is unknown in the art.

[0148] In practice, the amplitude of Bz is usually orders of magnitude larger than that of dBz / dx, which means that the signals h4 and h5 measured by the horizontal Hall elements located at X4 and X5 are insensitive to (Bx) and (dBx / dx), but mainly depend on (Bz).

[0149] Even if the gradient (dBz / dx) is not very small, the sum (h4+h5) of the signals obtained from the two horizontal Hall elements H4, H5 located at positions X4, X5 (e.g., Figure 7 (as shown in ), will also reduce or even completely eliminate the effect of dBz / dx, i.e., (h4+h5) is only sensitive to Bz, but insensitive to (dBz / dx), insensitive to (Bx) and insensitive to (dBx / dx).

[0150] from Figure 4 As can be appreciated from parts (a) to (d) of FIG. 1 , these “white areas” are located at a distance of approximately L / 3 from the center of the IMC (e.g., within a tolerance margin of ±3%). Neither the existence nor the locations of these locations are known in the art.

[0151] Figure 5A A magnetic sensor structure 505a is shown that includes an elongated IMC 513a and a single horizontal Hall element H2 positioned below the center of the IMC. As explained above, in an environment where the effect of Bz is not large at the location of H2, the signal h2 obtained from the horizontal Hall element H2 can be used as an estimate or indication of the magnetic field gradient (dBx / dx), for example according to the formula: h2≈2*Gx*(dBx / dx), where Gx is a predefined constant and the symbol ≈ means "approximately equal to". Of course, this can also be written as: h2≈Ax*(dBx / dx), where Ax is a predefined constant.

[0152] Figure 5B Shows Figure 5A A variant further includes a second horizontal Hall element H6 which is not located below the IMC but is spaced apart from the center of the IMC in the X direction by a distance d5x and spaced apart from the center of the IMC in the Y direction by a distance d5y. In the example shown, the value of d5x is different from zero, but this is not absolutely necessary and in Figure 5B In the variant of , the value of d5x is equal to 0. The value of d5y can be a value in the range of 2*W to 5*W, where W is the width of the IMC. Figure 3 According to the formula [2], the signal h2 obtained from the horizontal Hall element H2 can be written as: h2 = 2*Gx*(dBx / dx)+Gz*(Bz 2 ), where Bz 2 is the signal Bz at the position of H2; and the signal h6 obtained from the horizontal Hall element H6 can be written as: h6 = Bz 6 (No explicit scaling factor is mentioned here since signal h6 is not passively amplified by the IMC.) By subtracting value h6 from value h2, optionally after scaling one or both of h2 and h6 in the analog or digital domain, the effect of Bz2 can be substantially or completely eliminated.

[0153] In fact, Bz 2 and Bz 6 The values ​​of are usually about the same, and the values ​​of Gz are usually close to 1.0. In other words, Figure 5B The magnetic sensor structure 505b is capable of measuring gradient (dBx / dx) while reducing or substantially eliminating common mode signals.

[0154] exist Figure 5BIn a variant (not shown), the structure has a third horizontal Hall element H7, which is arranged so that H2 is positioned halfway between H6 and H7. The value of Bz2 can then be approximated by averaging the signals h6 and h7 obtained from Hall elements H6 and H7, respectively. The signal h2-K*avg(h6, h7) is an approximation of 2*Gx*(dBx / dx), even if Bz is not equal to zero, and even if Bz varies in the X or Y direction, where avg() means "average value of..." and K is a predefined constant that can be equal to 1.00 or can be different from 1.00 (for example, a value in the range from 0.90 to 0.98 or a value in the range from 1.02 to 1.10). The virtual line passing through H6 and H7 can be oriented perpendicular to the elongated direction X of the IMC, but this is not absolutely necessary.

[0155] Figure 5C and Figure 5D There are several illustrative examples showing embodiments of the present invention where the IMC has an elongated portion, preferably a rectangular or beam-shaped portion, but need not be a perfect beam throughout its entire length. Figure 5C Shows Figure 5A A variation of where the IMC 513c has radiused ends or rounded ends. Figure 5D Shows Figure 5A A variation of , in which the IMC 513d has triangular ends. However, other shapes, such as tapered ends or widened ends (ie, wider width near its ends), are also possible.

[0156] Figure 5C and Figure 5D The magnetic sensor structures 505c, 505d illustrated in FIG. 5 have only one horizontal Hall element H2 located at the center of the IMC, but of course, additional horizontal Hall elements may be added to the structure, such as one or both of H1 and H3 near the ends (e.g., as shown in FIG. Figure 1B ), H6 outside the IMC (e.g., Figure 5B ), H6 and H7 outside the IMC so that H2 is positioned in the middle between H6 and H7 (as shown in Figure 5B ), one or both of H4 and H5 in the "white area" (e.g., as described by variants of Figure 7 ), or a combination thereof.

[0157] Figure 6 An illustrative example of a magnetic sensor structure 605 is shown that includes an elongated IMC 613 and a first horizontal Hall element H2 positioned below the center of the IMC, and a second Hall element H4 located below the IMC at a distance d6 from the center. Figure 6The sensor structure can be viewed as Figure 5B A variant of the sensor structure in which the second horizontal Hall element is offset below the IMC, preferably in the "white area". In a preferred embodiment, d6 is a value in the range from L*0.30 to L*0.36, or in other words: preferably, the distance d6 is equal to L / 3 with a tolerance margin of ±3%. The processing circuit ( Figure 6 It is not explicitly shown in, but see e.g. Fig.11 ) can be configured to determine (e.g., calculate) a signal or value s6 as the difference between a signal h2 obtained from H2 and a signal h4 obtained from H4, for example, according to the formula s6=(h2-h4). The signal or value s6 can be used as an approximation of 2*Gx*(dBx / dx) and has reduced sensitivity to common mode signals.

[0158] Figure 7 An illustrative example of a magnetic sensor structure 705 is shown, which includes an elongated IMC 713 and a first horizontal Hall element H2 positioned below the center of the IMC, and includes a second horizontal Hall element H4 and a third horizontal Hall element H5 located below the IMC, offset from the center by distances d7b and d7a, respectively. Preferably, the distance d7a is equal to the distance d7b. The value of the distance can be a value in the range from L*26% to L*40%, or a value in the range from L*30% to L*36%, or a value in the range of (L / 3)±7%, or ±5%, or ±3%. Figure 7 The sensor structure 705 can be viewed as Figure 6 A variation of the sensor structure further includes a third horizontal Hall element H5, which is located below the IMC in the "white area". The processing circuits ( Figure 7 It is not explicitly shown in, but see e.g. Fig.11 ) can be configured to determine (e.g., calculate) a signal or value s7 according to the following formula s7=2*h2-(h4+h5). The signal or value s7 can be used as an approximation of 4*Gx*(dBx / dx) and has reduced sensitivity to common mode signals.

[0159] Fig. 8A and Figure 8B The diagram shows a circuit including an electrical conductor portion 820 (eg, a bus bar) and a Figure 1A or Figure 2800 and 800b are two illustrative examples of current sensor systems 800 and 800b having magnetic sensor structures 805 similar to the magnetic sensor structure in part (a), each magnetic sensor structure including an IMC and three horizontal Hall elements H2, H1, H3, one (H2) located at the center and two (H1, H3) located near the outer ends of the IMC. The magnetic sensor structure 805 can be implemented in a semiconductor substrate 810. The semiconductor substrate can be incorporated into a sensor device (not explicitly shown), such as a packaged sensor device, also referred to as a "chip".

[0160] Preferably, the IMC 813 is oriented with its longitudinal direction X being perpendicular to the direction Y of the current flowing through the conductor 820 . Or in other words, the IMC 813 is preferably oriented in the transverse direction of the busbar 820 .

[0161] exist Fig. 8A In the example of , the sensor structure 805 is positioned so that the element H2 is positioned near the lateral edge of the bus bar 820, but this is not absolutely necessary. It is sufficient that the central Hall element H2 is positioned offset from the center line 821 of the bus bar. Fig. 8A In the example of , the horizontal Hall element H3 is substantially located at the center line 821 of the bus bar 820, but this is not required, and the Hall element H3 can be located at a non-zero offset from the center line 821. Fig. 8A In the example shown in , the semiconductor substrate 810 including the sensor structure 813 has a width Ws1 that is greater than the width Wb of the bus bar, but this is not required.

[0162] The semiconductor substrate 810 may further include a processing circuit configured to determine a signal s8 according to the formula s8=(h1+h3-h2), or may be configured to determine a signal s8′ according to the formula s8′=(h1+h3-2*h2). The signal s8, and even s8′, depends primarily on the gradient signal and is largely independent of the common mode signal and is therefore substantially independent of external interference fields (if any).

[0163] The current flowing through the electrical conductor 820 can be calculated according to the formula I8=K8*(h1+h3-h2), or according to the formula I8'=K8'*(h1+h3-2*h2), where K8 and K8' are predefined constants that can be determined by design, by simulation, or during a calibration process and can be hard-coded or can be stored in a non-volatile memory of the sensor device (see, e.g. Fig.11 ).

[0164] exist Fig. 8A In a variation of FIG. 1 , the Hall elements H1 and H3 are not located near the ends of the IMC (e.g., Figure 1B ), but rather in the "white area" of the IMC (e.g., as shown in Figure 7 ).

[0165] Figure 8B A sensor system 800b is shown, which is Fig. 8A A variation of the sensor system 800 has a semiconductor substrate 810b including Figure 1A or Figure 2 The sensor structure in part (b) of FIG. 805 is similar to the sensor structure 805b. The Hall element H2 is preferably located near the lateral edge of the bus bar 820, but this is not absolutely necessary. The Hall element H3 is located between the lateral edge of the bus bar and the center line 821. Figure 8B The semiconductor substrate 810b preferably has a width Ws2 that is less than or equal to the width Wb of the bus bar 820. In an embodiment, the semiconductor substrate 810b is included in a packaged integrated sensor device ("chip"), and the size of the chip (in the lateral direction of the bus bar) is less than or equal to the width Wb of the bus bar.

[0166] and Fig. 8A The same formula as mentioned in applies here as well, but the values ​​of the predefined constants K8, K8' may be different.

[0167] exist Fig. 8A and Figure 8B In other variations, the substrate 810 or 810b may include Figure 7 The sensor structure shown in the figure, and the current I can be determined according to the formula I=K8"*[2*h2-(h4+h5)], where K8" is a predefined constant, which can be determined by design, by simulation, or during a calibration process, and h2, h4, h5 are signals obtained from the central Hall element H2 and from the other two Hall elements H4, H5, respectively.

[0168] exist Figure 8B In a variation of FIG. 1 , the Hall elements H1 and H3 are not located near the ends of the IMC (e.g., Figure 1B ), but rather in the "white area" of the IMC (e.g., as shown in Figure 7 ).

[0169] Fig.9A The diagram shows a circuit including an electrical conductor portion 920a (eg, a portion of a bus bar) and a Figure 5A900a, the two magnetic sensor structures 905a, 905b are preferably implemented in a semiconductor substrate 910a. The magnetic sensor structures 905a, 905b each include an IMC 913a, 913b and a horizontal Hall element H2a, H2b located in the middle of the respective IMC. It can be seen that the flux concentrators 913a and 913b are oriented in the X direction, perpendicular to the Y direction (i.e., in the current direction), or in the lateral direction of the conductor portion 920a. Preferably, the two IMCs 913a, 913b have the same shape and size.

[0170] exist Fig.9A In the example of , the sensor structures 905a, 905b are arranged so that the Hall element H2a is substantially located above the first edge e1 of the conductor portion 920a, and so that the Hall element H2b is substantially located above the second edge e2 of the conductor portion 920a. The Hall elements H2a, H2b can be connected to a processing circuit (not shown), which can be configured to determine a signal or value s9 according to the formula s9=(h2a-h2b), where h2a is a signal obtained from the Hall element H2a, and h2b is a signal obtained from the Hall element H2b. The processing circuit can be implemented in the same (e.g., single) substrate 910a, or in another substrate that can be operably connected to the substrate 910a, and in the latter case, is preferably incorporated in the same packaged device (e.g., a chip (not shown)). The processing circuit can be configured to determine the current I according to the formula I=K9*(h2a-h2b), where K9 is a predefined constant that can be determined by design, by simulation, or during a calibration process, and which can be stored in a non-volatile memory of the sensor device. The processing circuit can also be implemented in the same semiconductor substrate.

[0171] Many variations are possible. Fig.9A In the example of FIG. 1 , the two sensor structures 905a and 905b are implemented on a single semiconductor substrate 910a, but this is not absolutely necessary, and in a variant, they can be implemented in two separate substrates 910c, 910d. The two separate substrates can be incorporated into a single packaged device, or can be implemented in two separate chips (not shown).

[0172] exist Fig.9A and Fig. 9B In the example of , the two IMCs and the Hall elements H2a, H2b are located above the edges e1, e2 of the electrical conductor portion 920b, but this is not absolutely necessary, and the IMCs and the Hall elements H2a, H2b may be slightly offset inwards or outwards.

[0173] exist Fig.9A In the example of , the length L9 of the IMC is slightly greater than Wb / 2 (where Wb is the width of the busbar portion), but this is not absolutely necessary. Fig. 9B In the example of FIG. 1 , the length L9 of the IMC is substantially equal to or less than Wb / 2. Fig.9A The same formula mentioned in the formula can also be applied to Fig. 9B , but the value of K9 can be different. Fig.9A and Fig. 9B In the embodiments and their variants, the current sensors are primarily sensitive to magnetic field gradients or only to magnetic field gradients, ie they are highly independent of external interfering fields (if present).

[0174] Fig.10 An illustrative example of a current sensor system 1000 is shown, which includes a U-shaped conductor portion 1020 and a Figure 5A The magnetic sensor structures in FIG. 1 are similar to two magnetic sensor structures 1005 a and 1005 b .

[0175] The U-shaped bus bar 1020 may have two elongated legs (extending in the Y direction) and be interconnected by a bridge 1022 extending in the X direction. Each magnetic sensor structure 1005a, 1005b includes an IMC and a horizontal Hall element H2a, H2b located in the middle of the respective IMC. The two IMCs may have different sizes and / or shapes.

[0176] The first sensor structure 1005 a has a first IMC oriented in the Y direction, parallel to the legs and perpendicular to the bridge 1022 , and a first horizontal Hall element H2 a located near the middle of the first IMC may be positioned near an outer edge e1 of the bridge 1022 .

[0177] The second sensor structure 1005b has a second IMC oriented in the X direction, perpendicular to the legs and parallel to the bridge 1022, and a second horizontal Hall element H2b located near the middle of the second IMC may be positioned near an inner edge e2 of the bridge.

[0178] A processing circuit (not shown) may be connected to the Hall elements H2a, H2b and may be configured to calculate the signal s10 according to the formula s10=(h2a-h2b) and / or may be configured to determine the current I according to the formula I=K10*(h2a-h2b), where h2a is a signal obtained from the Hall element H2a, h2b is a signal obtained from the Hall element H2b, and K10 is a predefined constant that may be determined by design, by simulation, or during a calibration process and may be stored in a non-volatile memory connected to the processing circuit (e.g., as shown in FIG. 1 ). Fig.11 ). The signal s10 and / or the current I determined in this way depends primarily on the magnetic field gradient, ie is substantially independent of external interfering fields (if any).

[0179] exist Fig.10 In the example of FIG. 1 , the two sensor structures 1005a and 1005b may be implemented on a single semiconductor substrate 1010, but the present invention is not limited thereto, and the two sensor structures may be implemented in two separate semiconductor substrates, preferably arranged in a single virtual plane, at the same distance from the upper surface of the bus bar. These substrates may be incorporated into a single packaged device (not shown), or may be incorporated into two separate devices. The processing circuit may be incorporated on the semiconductor substrate 1010, but this is not absolutely necessary.

[0180] exist Fig.10 In the example shown, the U-shaped conductor portion 1020 has straight inner and outer corners, but this is not absolutely necessary and the present invention will also work if the U-shaped conductor portion has rounded inner or outer corners.

[0181] Fig.11 1 is a high-level block diagram of a magnetic sensor device 1120 proposed by the present invention. This diagram is provided only for completeness. It shows that the sensor device includes one or more horizontal Hall elements H2, H1, H3, etc., each sensor element provides a signal h2, h1, h3 to a processing circuit 1122, such as a controller (e.g., a programmable microcontroller).

[0182] Although not explicitly shown, the sensor device 1120 may have other circuits, such as, for example, biasing and readout circuitry, one or more amplifiers, one or more filters, one or more analog-to-digital converters (ADCs), etc. Such circuits are well known in the art and, therefore, need not be explained in further detail here.

[0183] Depending on the implementation, processing circuitry, one or more Hall elements, bias and readout circuitry, etc. may be incorporated into a single semiconductor substrate or multiple semiconductor substrates. The sensor device 1120 may include a non-volatile memory 1121 (e.g., flash memory) that may store one or more predefined constants or parameters (e.g., parameters for determining current values).

[0184] In an embodiment of the present invention, the sensor circuit 1122 includes one or more of the magnetic sensor structures illustrated above.

[0185] For example, it may include Figure 5A , the magnetic sensor structure 505a illustrated in FIG. 5 includes an elongated IMC 513a and a horizontal Hall element H2 located below the center of the IMC, and includes a processing circuit configured to provide a signal equal to or proportional to a signal h2 obtained from the Hall element H2;

[0186] Or it could include Figure 5B , the magnetic sensor structure 505b comprising an elongated IMC 513b and one horizontal Hall element H2 located below the center of the IMC and another horizontal Hall element H6 located outside the IMC, and comprising a processing circuit configured to provide a signal equal to or proportional to a signal (h2-h6), or a signal proportional to (h2-K*h6), wherein K is a predefined constant;

[0187] Or it could include Figure 6 , the magnetic sensor structure 605 comprising an elongated IMC 613 and one horizontal Hall element H2 located below the center of the IMC and another horizontal Hall element H4 located below the IMC, and comprising a processing circuit configured to provide a signal equal to or proportional to the signal (h2-h4);

[0188] Or it could include Figure 7 , the magnetic sensor structure 705 comprising an elongated IMC 713 and one horizontal Hall element H2 located below the center of the IMC and two other horizontal Hall elements H4, H5 located below the IMC, and comprising a processing circuit configured to provide a signal equal to or proportional to the signal 2*h2-(h4+h5);

[0189] Or it could include Fig. 8A or Figure 8B, the magnetic sensor structure 805 comprising an elongated IMC and one horizontal Hall element H2 located below the center of the IMC and two horizontal Hall elements H1, H3 located below the IMC, and comprising a processing circuit configured to provide a signal equal to or proportional to a signal s8=(h1+h3-h2) or a signal equal to or proportional to a signal s8'=(h2+h3-2*h2);

[0190] Or it could include Fig.9A or Fig. 9B , the two magnetic sensor structures each comprising an elongated IMC and a horizontal Hall element H2a, H2b located below the center of the respective IMC, wherein the two IMCs are oriented parallel to each other and are located on the same virtual line; and comprising a processing circuit configured to provide a signal equal to or proportional to the signal (h2a-h2b) obtained from the two Hall elements H2a, H2b;

[0191] Or it could include Fig.10 , the two magnetic sensor structures each comprising an elongated IMC and a horizontal Hall element H2a, H2b located below the center of the respective IMC, wherein the two IMCs are oriented perpendicular to each other; and comprising a processing circuit configured to provide a signal equal to or proportional to the signal (h2a-h2b) obtained from the two Hall elements H2a, H2b;

[0192] In certain embodiments, the gradient signal may be converted into a distance value, for example by using a predefined function or a lookup table, and the sensor device 1120 is a distance sensor device.

[0193] In some embodiments, the first gradient signal is a sine-like signal and the second gradient signal is a cosine-like signal, and the sensor device is configured to determine a linear or angular position based on the first gradient signal and the second gradient signal, and the sensor device 1120 is a position sensor device.

[0194] The invention also relates to a method for determining a signal which is primarily dependent on one or more magnetic field gradients (e.g. dBx / dx) and which is substantially independent of external interfering fields, the method comprising the following steps:

[0195] a) providing at least one semiconductor substrate, the semiconductor substrate comprising at least one horizontal Hall element (H2) embedded in the semiconductor substrate;

[0196] b) providing a magnetic flux concentrator (IMC) on the semiconductor substrate, the magnetic flux concentrator having an elongated portion extending in a first direction (X) parallel to the substrate and arranged such that the horizontal Hall element (H2) is positioned below the center of the IMC.

[0197] Step a) may include: providing the semiconductor substrate as a CMOS substrate, further including bias and readout circuits, and processing circuits;

[0198] Step a) may include, for example, at one or more locations that will not be located below the IMC (e.g., similar to Figure 5B H6), or at one or more locations that will be below the IMC (e.g., similar to Figure 6 H4 as shown in the figure, or similar Figure 7 H4 and H5 as shown in the figure, or similar Fig.9A or Fig. 9B H1 and H3) illustrated in the figure provide the semiconductor substrate including at least two or at least three horizontal Hall elements.

[0199] Step b) may further include: providing a second IMC on the semiconductor substrate, the second IMC being oriented, for example, parallel to the first IMC (eg, Fig.9A or Fig. 9B ) or perpendicular to the first IMC orientation (e.g., Fig.10 middle).

[0200] The method may further comprise one or more of the following steps:

[0201] c) for example as described above and / or as Fig. 8A , Figure 8B , Fig.9A , Fig. 9B , Fig.10 Arranging at least one semiconductor substrate relative to the electrical conductor portion in the manner illustrated in any one of the claims;

[0202] d) determining a value indicative of a current flowing through the conductor portion based on the signal obtained from the at least one horizontal Hall element (eg as a linear combination thereof).

[0203] Reference numerals:

[0204] In the different embodiments, similar elements are generally designated by similar reference numerals modulo 100 .

[0205] -00: Magnetic sensor system (e.g., current sensor system)

[0206] -05: Magnetic sensor structure

[0207] -10: Magnetic sensor device (e.g., semiconductor substrate)

[0208] -11: Substrate

[0209] -12: polymer layer (e.g., polyimide layer)

[0210] -13:IMC

[0211] -20: Electrical conductor part of the busbar

[0212] -21: Centerline

[0213] -22: U-shaped bridge H1, H2, H3 and other horizontal Hall element L length

[0214] W Width

[0215] T Thickness

Claims

1. A sensor device (810; 910a; 1010), the sensor device comprises: At least one integrated magnetic sensor structure (105; 205; 505a; 505b; 605; 705; 805; 805b; 905a; 1005a; 1005b), the at least one integrated magnetic sensor structure comprising: Semiconductor substrate; a magnetic flux concentrator (IMC) disposed on top of the semiconductor substrate, the magnetic flux concentrator (IMC) having a predefined shape with an elongated portion extending in a first direction (X) parallel to the semiconductor substrate; a horizontal Hall element (H2) disposed in or on the substrate and positioned below the center of the IMC; a processing circuit connected to the horizontal Hall element (H2) and configured to provide a signal or value indicative of at least one magnetic field gradient (dBx / dx) of a magnetic field surrounding the at least one integrated magnetic sensor structure, or a signal or value derived from the signal or value indicative of the at least one magnetic field gradient (dBx / dx).

2. The sensor device according to claim 1, in, The predefined shape is an overall beam shape having a predefined length (L) and a predefined width (W); Or wherein the elongated portion has an overall rectangular cross-section in a plane parallel to the substrate, the overall rectangular cross-section having a predefined length (L) and a predefined width (W).

3. The sensor device according to claim 2, in, A ratio L / W of the length L to the width W is at least 3.0; or wherein the ratio L / W of the length L to the width W is a value in the range of 3.0 to 20.0; or wherein the ratio L / W of the length L to the width W is a value in the range of 4.0 to 10.0; Or wherein a ratio L / W of the length L to the width W is a value in the range of 5.0 to 10.

0.

4. The sensor device according to claim 1, in, The sensor device includes only a single magnetic flux concentrator (IMC) having a magnetic flux concentrator (513a; 513b; 913a； 913b; 1013a, 1013b) below only one horizontal Hall element (H2); Or wherein the sensor device comprises two magnetic flux concentrators (IMC), each of the two magnetic flux concentrators (IMC) having only one horizontal Hall element (H2a, H2b) positioned below the IMC.

5. The sensor device according to claim 1, in, The IMC has an elongated shape extending over a predefined length (L); and The integrated magnetic sensor structure further comprises a second horizontal Hall element (H4), which is positioned below the IMC and spaced apart from the center of the IMC by a distance in a range from L*26% to L*40%.

6. The sensor device according to claim 1, in, The IMC has an elongated shape extending over a predefined length (L); and In which, the integrated magnetic sensor structure further includes a second horizontal Hall element and a third horizontal Hall element (H1, H3; H4, H5), and the second horizontal Hall element and the third horizontal Hall element (H1, H3; H4, H5) are arranged so that the first horizontal Hall element (H2) is positioned in the middle between the second horizontal Hall element and the third horizontal Hall element.

7. The sensor device according to claim 6, in, The distance (d12) between the center of the IMC and the second and third horizontal Hall elements (H1, H3) is at least L*41%; Or wherein the distance (d7a, d7b) between the center of the IMC and the second and third horizontal Hall elements (H4, H5) is a distance in the range from L*26% to L*40%.

8. The sensor device according to claim 1, in, the sensor device being a current sensor device configured to measure a characteristic of a magnetic field generated by a current flowing through an electrical conductor portion; Wherein, the processing circuit is configured to provide a signal or value indicative of the current based on at least one signal obtained from the at least one horizontal Hall element.

9. The sensor device (810; 1120) according to claim 8, An integrated magnetic sensor structure is included, wherein the integrated magnetic sensor structure includes an IMC and three horizontal Hall elements (H1, H2, H3); in, The processing circuit is configured to determine the current according to the formula I=K*(h1+h3-h2), or according to the formula I=K*(h1+h3-2*h2), Wherein, K is a predefined constant, h1 and h3 are signals obtained from the second and third horizontal Hall elements (H1, H3) located near the ends of the IMC, and h2 is a signal obtained from the horizontal Hall element (H2) located near the center of the IMC.

10. The sensor device (910; 1010; 1120) according to claim 8, comprising a first integrated magnetic sensor structure and a second integrated magnetic sensor structure, wherein the first integrated magnetic sensor structure comprises a first IMC and a first horizontal Hall element (e.g., H2a) located below the center of the first IMC, and the second integrated magnetic sensor structure comprises a second IMC and a second horizontal Hall element (e.g., H2b) located below the center of the second IMC; in, The processing circuit is configured to determine the current according to the formula I=K*(h2a-h2b), where K is a predefined constant, h2a is the signal obtained from the first horizontal Hall element (H2a), and h2b is the signal obtained from the second horizontal Hall element (H2b).

11. The sensor device (910; 1010; 1120) according to claim 8, in, The first IMC (IMC1) and the second IMC (IMC2) are oriented in parallel and are located on a virtual line (X); or wherein the first IMC (IMC1) and the second IMC (IMC2) are oriented in parallel and are spaced apart so as to define a virtual rectangle; Or wherein the first IMC (IMC1) and the second IMC (IMC2) are oriented perpendicular to each other and are spaced apart from each other.

12. The sensor device according to claim 1, in, The sensor device is a distance sensor device; or wherein the sensor device is a proximity sensor device; or wherein the sensor device is a linear position sensor device; Or wherein the sensor device is an angular position sensor device.

13. A current sensor system (800; 900; 1000), the current sensor system (800; 900; 1000) comprising: The sensor device (810) according to claim 8; An electrical conductor portion (820) extending in a predefined direction (Y).

14. The current sensor system (800) according to claim 13, in, The integrated magnetic sensor structure (805) includes three horizontal Hall elements arranged below the IMC; And wherein the IMC is oriented perpendicular to the predefined direction (Y).

15. The current sensor system (900; 1000) according to claim 13, in, The current sensor device comprises a first IMC and a first horizontal Hall element (H2a) arranged below the center of the first IMC, and a second IMC and a second horizontal Hall element (H2b) arranged below the center of the second IMC, the current sensor device being arranged in one of the following ways: i) Among them, The first IMC and the second IMC are located on a virtual line (X), and the current sensor device is oriented such that the virtual line is oriented perpendicular to the predefined direction; ii) wherein the first IMC and the second IMC are oriented parallel to a predefined direction and are spaced apart so as to define a virtual rectangle; and wherein the electrical conductor portion has a first transverse cutout and a second transverse cutout; and wherein the first horizontal Hall element (H2a) is positioned above the first cutout and the second horizontal Hall element (H2b) is positioned above the second cutout; iii) wherein the conductor portion has a U-shape comprising two legs interconnected by a bridge (1022); and wherein the first IMC is oriented perpendicular to the bridge and the first horizontal Hall element (H2a) is positioned near an outer edge (e1) of the bridge; and wherein the second IMC is oriented parallel to the bridge and the second horizontal Hall element (H2b) is positioned between the two legs near an inner edge (e2) of the bridge.

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