magnetic sensor device

Abstract

To provide a magnetic sensor device that can suitably fix a sensor substrate to a support substrate and has stable output characteristics.SOLUTION: A magnetic sensor device 1 comprises a support substrate 2 and a sensor substrate 10 fixed to the support substrate 2. The sensor substrate 10 includes: a first surface 10B facing the support substrate 2; and a second surface 10A that is located on an opposite side to the first surface 10B, the second surface 10A being provided with a functional film 20 including a plurality of magnetic detection elements E. A hole portion 11 is formed in the first surface 10B. An outline O11 of the hole portion 11 includes at least one corner C1, C2, C3..., and each of the plurality of magnetic detection elements E is disposed not to overlap any of the at least one corner C1, C2, C3... in a plan view seen in a plane-normal direction Z from the second surface 10A toward the first surface 10B.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present disclosure relates to a magnetic sensor device. [Background technology]

[0002] There is a magnetic sensor device in which a sensor chip, on which a magnetic detection element is provided on a sensor substrate, is attached to a support substrate with an adhesive. For example, Patent Document 1 discloses a magnetic sensor device in which a first chip and a second chip, each including a magnetic sensor that generates a detection signal, and a support that includes an application specific integrated circuit (ASIC) for processing the detection signal are prepared separately, and the first chip and the second chip are joined to the support with an adhesive.

[0003] In such a magnetic sensor device, it is preferable to apply the adhesive so that it slightly protrudes beyond the adhesive surface of the sensor substrate. If the amount of adhesive applied is insufficient, peeling may occur starting from the areas where the adhesive is not applied, and the adhesive strength may decrease. If the amount of adhesive applied is excessive, the adhesive that protrudes from the sensor substrate may adhere to the electrodes on the surface of the ASIC, etc., and the connection reliability may decrease.

[0004] If a blind hole or through hole is formed on the adhesive surface of the sensor substrate, the amount of adhesive that overflows from the sensor chip due to surface tension is less likely to change even if the amount of adhesive applied varies slightly. The adhesive layer becomes thicker, improving adhesive strength. Patent Document 2, while not a magnetic sensor device, discloses forming a recess on the back surface of the semiconductor element facing the support substrate in a semiconductor device in which a semiconductor element is mounted on a support via an adhesive layer. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-10557 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-205893 Summary of the Invention [Problem to be solved by the invention]

[0006] However, unlike the semiconductor device described in Patent Document 2, the magnetic sensor device includes a magnetic detection element made of a magnetic material. When an external force is applied to a magnetic material, its response to the magnetic field fluctuates due to the inverse magnetostriction effect. In particular, while tunnel magnetoresistance effect elements have excellent output characteristics with a large MR ratio, their output characteristics are easily fluctuated by external forces. Furthermore, forming blind holes or through holes in the sensor substrate causes local changes in the thickness of the sensor substrate, which can lead to uneven thermal deformation when the sensor substrate expands or contracts due to temperature changes, potentially causing thermal stress to act on the magnetic detection element.

[0007] The present disclosure has been made in view of the above circumstances, and has an object to provide a magnetic sensor device in which a sensor substrate can be suitably fixed to a support substrate and output characteristics are stable. [Means for solving the problem]

[0008] A magnetic sensor device according to one aspect of the present disclosure includes a support substrate and a sensor substrate fixed to the support substrate. The sensor substrate has a first surface facing the support substrate and a second surface opposite the first surface, the second surface having a functional film including a plurality of magnetic detection elements. A hole is formed in the first surface, the outline of the hole including at least one corner, and each of the plurality of magnetic detection elements is arranged so as not to overlap with any of the at least one corner in a plan view seen in a direction perpendicular to the surface from the second surface toward the first surface. The hole may be a bottomed hole recessed from the first surface toward the second surface, or a through hole penetrating from the first surface to the second surface.

[0009] A magnetic sensor device according to another aspect of the present disclosure includes a support substrate and a sensor substrate fixed to the support substrate. The sensor substrate has a first surface facing the support substrate and a second surface opposite the first surface, the second surface having a functional film including a plurality of magnetic detection elements. A hole is formed in the first surface, and the outline of the hole is a circle without corners.

[0010] According to these aspects, since holes are formed in the sensor substrate, the amount of adhesive that overflows from the underside of the sensor substrate is less likely to change even if the amount of adhesive applied changes, compared to when holes are not formed. The adhesive layer becomes thicker and the adhesive strength is improved. Therefore, the sensor substrate can be suitably attached to the support substrate. In a plan view, the position that overlaps with the corners of the hole outline is susceptible to the influence of thermal stress. According to these aspects, since each of the multiple magnetic detection elements does not overlap with any of the corners, a magnetic sensor device can be provided that is less susceptible to the influence of thermal stress and has stable output characteristics.

[0011] In the above aspect, the sensor substrate may be fixed to the support substrate using an adhesive, and the holes may be filled with the adhesive.

[0012] According to this aspect, the sensor substrate can be suitably fixed to the support substrate by the adhesive.

[0013] In the above aspect, the plurality of magnetic detection elements may be arranged so as not to overlap the contour in a plan view.

[0014] Positions other than the corners that overlap the contour of the hole are slightly more susceptible to the effects of thermal stress than positions that do not overlap the contour, although not as susceptible as positions that overlap the corners. According to this aspect, because each of the multiple magnetic detection elements does not overlap either the corners or the contour, it is even less susceptible to the effects of thermal stress, resulting in stable output characteristics.

[0015] In the above aspect, some of the magnetic detection elements may be arranged inside the outline in a plan view, and the rest of the magnetic detection elements may be arranged outside the outline in a plan view. All of the magnetic detection elements may be arranged inside the outline in a plan view. All of the magnetic detection elements may be arranged outside the outline in a plan view.

[0016] According to these aspects, the magnetic detection elements can be arranged both inside and outside the outline, or only inside the outline, or only outside the outline. There are few restrictions on the arrangement of the magnetic detection elements, allowing for excellent design freedom.

[0017] In the above aspect, each of the plurality of magnetic detection elements may be arranged at an interval of 1 μm or more from the contour in a direction perpendicular to the surface-normal direction.

[0018] According to this embodiment, each of the magnetic detection elements is located at a distance of at least 1 μm from the contour, and therefore is less susceptible to the effects of thermal stress.

[0019] In the above aspect, the plurality of magnetic detection elements may include at least one first magnetic detection element arranged so as to overlap the contour in a plan view seen in a direction perpendicular to the surface from the second surface to the first surface.

[0020] According to this aspect, the first magnetic detection element can be arranged so as to overlap the contour of the hole. Although the positions overlapping the contour of the hole other than the corners are slightly more susceptible to the influence of thermal stress than positions not overlapping the contour, the influence of thermal stress is sufficiently small compared to positions overlapping the corners, making it possible to provide a magnetic sensor device with stable output characteristics. Compared to when the contour of the hole must be completely avoided, there are fewer restrictions on the arrangement of the magnetic detection elements, allowing for greater design freedom.

[0021] In the above aspect, the plurality of magnetic detection elements may further include a plurality of second magnetic detection elements arranged so as not to overlap the outline in a plan view, and some of the plurality of second magnetic detection elements may be arranged inside the outline in a plan view, and the remainder of the plurality of second magnetic detection elements may be arranged outside the outline in a plan view. All of the at least one second magnetic detection element may be arranged inside the outline in a plan view. All of the at least one second magnetic detection element may be arranged outside the outline in a plan view.

[0022] According to these aspects, it is possible to arrange the second magnetic detection elements both inside and outside the contour by mixing the first magnetic detection elements that overlap the contour and the second magnetic detection elements that do not overlap the contour, or to arrange the second magnetic detection elements only inside the contour, or to arrange the second magnetic detection elements only outside the contour. There are few restrictions on the arrangement of the magnetic detection elements, allowing for excellent design freedom.

[0023] In the above aspect, the plurality of magnetic detection elements may be arranged at intervals of 1 μm or more from all of at least one corner in an in-plane direction perpendicular to the perpendicular direction.

[0024] According to this aspect, each of the magnetic detection elements is located at least 1 μm away from the corner, and therefore is less susceptible to the effects of thermal stress.

[0025] In the above aspect, the hole may be a bottomed hole recessed from the first surface toward the second surface, and the depth of the bottomed hole may be equal to or less than half the thickness of the sensor substrate in the direction perpendicular to the surface.

[0026] The deeper the hole, the greater the difference in plate thickness between the hole and non-hole areas, making the magnetic detection element more susceptible to the effects of thermal stress when the sensor substrate expands or contracts due to temperature changes. According to this aspect, the difference in plate thickness between the hole and non-hole areas is less than half the plate thickness, making it possible to provide a magnetic sensor device with stable output characteristics and less susceptible to the effects of thermal stress.

[0027] In the above aspect, the magnetic sensor may further include a wiring layer provided in a layer farther from the support substrate than the functional film in the direction perpendicular to the surface, and each of the multiple magnetic detection elements may be arranged inside the outline of the wiring layer in a planar view.

[0028] If the magnetic sensing element is disposed inside the outline of the wiring layer, the magnetic sensing element is less susceptible to the effects of thermal stress than if there were no wiring layer.

[0029] In the above aspect, the hole may have an inner surface that is inclined relative to the direction perpendicular to the surface, and the plurality of magnetic detection elements may be arranged so as not to overlap the inner surface in a plan view.

[0030] The position where the magnetic detection elements overlap the inclined inner surface is susceptible to the influence of thermal stress. According to this aspect, since each of the magnetic detection elements does not overlap the inclined inner surface, it is possible to provide a magnetic sensor device that is less susceptible to the influence of thermal stress and has stable output characteristics.

[0031] In the above aspects, the angle sensor may be equipped with a magnetic sensor device, the magnetic compass may be equipped with a magnetic sensor device, the current sensor may be equipped with a magnetic sensor device, or the autofocus mechanism and / or the optical image stabilization mechanism of the camera module may be equipped with a magnetic sensor device.

[0032] According to these aspects, the magnetic sensor device can be used for various purposes. [Effects of the Invention]

[0033] According to the present disclosure, it is possible to provide a magnetic sensor device in which a sensor substrate can be suitably fixed to a support substrate and output characteristics are stable. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 1 is a perspective view showing a magnetic sensor device according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view schematically illustrating an example of the internal structure of the magnetic sensor device shown in FIG. [Figure 3] FIG. 3 is a perspective view illustrating a manufacturing process of the magnetic sensor device shown in FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of a magnetic sensor device configured as an angle sensor. [Figure 5] FIG. 5 is a plan view showing an example of a magnetic sensor device configured as a magnetic compass. [Figure 6] FIG. 6 is a diagram showing an example of a magnetic sensor device used as a part of a current sensor. [Figure 7] FIG. 7 is a diagram showing a circuit configuration of the current sensor shown in FIG. [Figure 8] FIG. 8 is a perspective view showing an example of a magnetic sensor device used as a part of an autofocus mechanism and an optical image stabilization mechanism of a camera module. [Figure 9] FIG. 9 is a cross-sectional view showing the internal structure of the camera module shown in FIG. [Figure 10A] FIG. 10A is a plan view of a simulation model in which a square hole is formed, viewed from a direction perpendicular to the surface. [Figure 10B] FIG. 10B is a plan view of a simulation model in which a rectangular hole with rounded corners is formed, as viewed from a direction perpendicular to the surface. [Figure 10C] FIG. 10C is a plan view of the simulation model in which a circular hole is formed, viewed from the perpendicular direction. [Figure 10D] FIG. 10D is a plan view of a simulation model further including a wiring layer, as viewed from the perpendicular direction. [Figure 10E] FIG. 10E is a plan view of a simulation model having an inclined inner surface as viewed from a direction perpendicular to the surface. [Figure 11] FIG. 11 is a cross-sectional view of the simulation model as viewed along the XY plane perpendicular to the surface normal direction. [Figure 12-13] 12 and 13 are diagrams showing simulated angular errors at the positions shown in FIGS. 10A and 11. FIG. [Figure 14]FIG. 14 is a diagram showing simulated angular errors at the positions shown in FIGS. 10A, 10B, and 10C. [Figure 15] FIG. 15 is a diagram showing angle errors obtained by simulating a model having the wiring layer shown in FIG. 10D at each of the positions shown in FIGS. 10A, 10B, and 10C. [Figure 16] FIG. 16 is a diagram showing simulated angular errors at each position shown in FIG. 10E. [Figure 17-20] 17 to 20 are plan views showing first to fourth examples in which all of the magnetic detection elements are arranged so as not to overlap the outline of the hole. [Figure 21-23] Figures 21 to 23 are plan views showing fifth to seventh examples in which the first magnetic detection element is arranged so as to overlap the outline of the hole portion other than the corner, and the second magnetic detection element is arranged so as not to overlap the outline of the hole portion. [Figure 24] FIG. 24 is a plan view showing an eighth example in which the magnetic detection element is arranged inside the outline of the wiring layer. [Figure 25] FIG. 25 is a cross-sectional view showing a ninth example in which the magnetic detection element is arranged so as not to overlap the inclined inner surface. DETAILED DESCRIPTION OF THE INVENTION

[0035] A preferred embodiment will be described with reference to the accompanying drawings. In each drawing, components with the same reference numerals have the same or similar configurations. A magnetic sensor device 1 according to an embodiment of the present disclosure is characterized in that a hole 11 is formed in a sensor substrate 10. As shown in FIGS. 17 to 24 , in a plan view along the perpendicular direction Z, each of the magnetic detection elements E is arranged so as not to overlap corners C1, C2, C3, etc. of the contour O11 of the hole 11. The contour O11 of the hole 11 may be a polygon such as a rectangle including multiple corners C1, C2, C3, etc., or a circle without corners C1, C2, C3, etc. The corners C1, C2, C3, etc. may be, for example, vertices C1, C2, C3, etc. where the curvature reaches a maximum value. The contour O11 of the hole 11 may be a teardrop-shaped shape formed by a combination of a vertex C1 and a curve. For example, in the case of a circular arc with a constant curvature sandwiched between two straight lines such as a corner R, the corners C1, C2, C3, . . . may be the midpoints of the circular arc (see FIG. 10B).

[0036] A magnetic sensor device 1 according to one embodiment of the present disclosure comprises a support substrate 2 and a sensor substrate 10 fixed to the support substrate 2 with an adhesive AD. The sensor substrate 10 has a first surface 10B facing the support substrate 2 and a second surface 10A located opposite the first surface 10B, on which a functional film 20 including a plurality of magnetic detection elements E is provided. The adhesive AD is filled into a hole 11 formed in a bottomed hole recessed from the first surface 10B toward the second surface 10A or a through hole penetrating from the first surface 10B to the second surface 10A. The contour O11 of the hole 11 includes at least one vertex C1, C2, C3... at which the curvature has a maximum value. Each of the plurality of magnetic detection elements E is arranged so as not to overlap with at least one of the vertices C1, C2, C3... in a planar view along the plane-normal direction Z from the second surface 10A toward the first surface 10B. In a magnetic sensor device 1 according to another embodiment of the present disclosure, the contour O11 of the hole 11 is circular and does not include vertices C1, C2, C3... where the curvature has a local maximum value. The magnetic sensor device 1 according to the present disclosure has the same or corresponding special technical feature in that the magnetic detection element E is arranged so as not to overlap with the vertices C1, C2, C3... where the curvature has a local maximum value, whether the contour O11 of the hole 11 is polygonal or circular. Each configuration will be described in detail below with reference to FIGS. 1 to 25.

[0037] 1 is a perspective view showing a magnetic sensor device 1 according to one embodiment. In the illustrated example, the magnetic sensor device 1 includes a support substrate 2, a sensor chip 3, a wiring layer 4, a sealing resin 5, and electrodes 6. One magnetic sensor device 1 may include multiple sensor chips 3.

[0038] 1, the support substrate 2 is formed in a flat plate shape having an upper surface 2A and a lower surface 2B opposite to the upper surface 2A. In the following description, the thickness direction of the support substrate 2 is referred to as the plane-normal direction Z or the up-down direction Z, the direction from the lower surface 2B to the upper surface 2A is referred to as the upward direction, and the direction from the upper surface 2A to the lower surface 2B is referred to as the downward direction. The upper surface 2A extends parallel to the XY plane that is perpendicular to the plane-normal direction Z.

[0039] Fig. 2 is a cross-sectional view schematically showing an example of the internal structure of the magnetic sensor device 1 shown in Fig. 1. In the example shown, the support substrate 2 is an ASIC (Application Specific Integrated Circuit), and an electrode 2E electrically connected to the wiring layer 4 is provided on the upper surface 2A. The support substrate 2 is not limited to an ASIC, and may be a silicon substrate or a sapphire substrate. These substrates may also be relay substrates (interposers) on which only wiring is formed, without including an integrated circuit.

[0040] The sensor chip 3 is fixed to the upper surface 2A of the support substrate 2 with an adhesive AD. As shown in Fig. 2, the sensor chip 3 includes a sensor substrate 10, at least one magnetic detection element array 30 that generates detection signals, and a functional film 20 that surrounds the magnetic detection element array 30. The functional film 20 may be an inorganic film containing silica (silicon dioxide SiO2) as its main component, or may be a laminated film of an inorganic film containing silica as its main component and an inorganic film containing alumina (aluminum oxide Al2O3) as its main component.

[0041] The sensor substrate 10 is, for example, a silicon substrate, and is disposed between the upper surface 2A of the support substrate 2 and the functional film 20. The sensor substrate 10 has a first surface (lower surface) 10B facing the support substrate 2 and a second surface 10A opposite the first surface 10B. The functional film 20 including the magnetic detection element array 30 is provided on the second surface 10A. A hole 11 that can be filled with adhesive AD is formed on the first surface 10B of the sensor substrate 10. The hole 11 may be a bottomed hole recessed from the first surface 10B toward the second surface 10A of the sensor substrate 10, or may be a through-hole that penetrates from the first surface 10B to the second surface 10A.

[0042] Each magnetic detection element array 30 is composed of a plurality of magnetic detection elements E (shown in FIG. 17) connected in a daisy chain and arranged in a matrix. One example of the magnetic detection element E is a TMR (tunnel magnetoresistance effect) element. The magnetic detection element E is not limited to a TMR element, but may be a GMR (giant magnetoresistance effect) element, an AMR (anisotropic magnetoresistance effect) element, a Hall element, or another type of magnetic detection element. The TMR element is particularly suitable as the magnetic detection element E because, compared to other types of MR elements, its smaller junction area allows for the miniaturization of the sensor chip 3, and its larger MR ratio allows for the increase in output of the sensor chip 3.

[0043] The magnetic detection element array 30 is disposed on the upper surface 2A side of the support substrate 2 and is formed on a first layer L1 on the upper surface 2A side of the support substrate 2. The wiring layer 4 is disposed on the upper surface 2A side of the support substrate 2 and is formed on a second layer L2 different from the first layer L1. The second layer L2 is farther from the support substrate 2 than the first layer L1.

[0044] The wiring layer 4 extends parallel to the upper surface 2A of the support substrate 2, and electrically connects the electrodes 2E of the support substrate 2 to the electrodes 3E provided on the upper surface 3A of the sensor chip 3 through a plurality of vias 40 extending in the direction perpendicular to the surface Z. The wiring layer 4 is arranged so as to partially overlap the sensor substrate 10 in the direction perpendicular to the surface Z.

[0045] The sealing resin 5 is disposed on the upper surface 2A side of the support substrate 2 and covers the sensor chip 3 and the wiring layer 4. The sealing resin 5 is configured by laminating multiple resin layers 51, 52, and 53 (shown in FIG. 3) that extend parallel to the upper surface 2A of the support substrate 2. The wiring layer 4 is, for example, copper plating provided on the upper surfaces of the resin layers 51 and 52. The electrodes 6 are, for example, solder balls or copper pillars, and are electrically connected to the wiring layer 4 and exposed from the sealing resin 5.

[0046] 3 is a perspective view illustrating a manufacturing process of the magnetic sensor device 1 shown in FIG. 1. As shown in FIG. 3(A), the sensor chip 3 is fixed to the upper surface 2A of the support substrate 2 with adhesive AD (shown in FIG. 2). If the amount of adhesive AD applied is insufficient, the sensor chip 3 is likely to peel off from the areas where the adhesive is not applied, whereas if the amount of adhesive AD applied is excessive, the adhesive that has spilled out from the sensor chip 3 will adhere to the electrodes 2E on the upper surface 2A of the support substrate 2. Therefore, it is preferable to apply the adhesive AD so that it slightly spills out from the lower surface of the sensor chip 3.

[0047] As shown in Fig. 3(B), a resin layer (first resin layer) 51 is formed to cover the sensor chip 3 and the upper surface 2A of the support substrate 2, and through holes 40P for the vias 40 (shown in Fig. 2) are opened at the positions of the electrodes 2E, 3E (shown in Fig. 10). As shown in Fig. 3(C), a seed layer is formed by sputtering or the like, and the vias 40 and the first wiring layer 41 are formed by plating. The process shown in Fig. 3(C) may be a subtractive method or an additive method.

[0048] As shown in FIG. 3(D), a resin layer (second resin layer) 52 is formed to cover the via 40, the first wiring layer 41, and the resin layer 51, and a through hole 40P for the via 40 is opened. As shown in FIG. 3(E), the via 40 and the second wiring layer 42 are formed by a process similar to that of FIG. 3(C). As shown in FIG. 3(F), a resin layer (third resin layer) 53 is formed to cover the via 40, the second wiring layer 42, and the resin layer 52, and a through hole 6P for the electrode 6 is opened. As shown in FIG. 3(G), the through hole 6P is filled with solder or the like to form the electrode 6. By following the steps shown in FIGS. 3(A) to 3(G), the support substrate 2 and the sensor chip 3, which are separately prepared, are electrically connected to obtain the magnetic sensor device 1 shown in FIG. 1.

[0049] 4 is a diagram showing an example of a magnetic sensor device 1 configured as an angle sensor that generates a detection value corresponding to the angle of a detection target. In the example shown, the magnetic sensor device 1 is configured as an angle sensor that detects the angle of a magnet 300 that can rotate around a central axis O of a cylinder as the rotation axis. In the example shown, the X direction, Y direction, and Z direction are perpendicular to one another, and the central axis O is parallel to the Z direction.

[0050] The magnetic sensor device 1 detects a first component of the magnetic field MF generated by the magnet 300 in a direction parallel to the X direction and applied to the magnetic sensor device 1, and generates a first detection signal representing the intensity of the first component, and detects a second component of the magnetic field generated by the magnet 300 in a direction parallel to the Y direction and generates a second detection signal representing the intensity of the second component. A processor (not shown) calculates the arc tangent of the ratio between the first detection signal and the second detection signal to calculate the angle θ that the magnetic field generated by the magnet 300 makes with respect to the reference direction DR.

[0051] Fig. 5 is a diagram showing an example of a magnetic sensor device 1 configured as a magnetic compass that generates detection values ​​corresponding to the angle of the geomagnetic field. As shown in Fig. 5, the magnetic sensor device 1 includes three sensor chips 3 (first to third sensor chips 3X, 3Y, and 3Z), and the first to third sensor chips 3X, 3Y, and 3Z are configured to detect components of an external magnetic field in three directions that are orthogonal to each other, respectively.

[0052] 6 is a diagram showing an example of a magnetic sensor device 1 used as part of a current sensor 400 that generates a detection value corresponding to the value of a current to be detected. In the example shown, the current sensor 400 is configured to detect the value of a current Itg flowing through a bus bar 410. A magnetic field MF is generated around the bus bar 410 by the current Itg. The current sensor 400 is disposed in the vicinity of the bus bar 410 at a position where the magnetic field MF is applied.

[0053] FIG. 7 is a diagram showing the circuit configuration of the current sensor 400 shown in FIG. 6. In the illustrated example, the current sensor 400 is configured as a magnetic balance current sensor. The current sensor 400 includes a coil 420 in addition to the magnetic sensor device 1. The coil 420 is for generating a second magnetic field MF2 that cancels out the first magnetic field MF1 of the magnetic field MF. The magnetic sensor device 1 detects the residual magnetic field between the first magnetic field MF1 and the second magnetic field MF2, and generates a magnetic field detection value S corresponding to the strength of the magnetic field.

[0054] The current sensor 400 further includes a feedback circuit 430, a current detector 440, and the like. The feedback circuit 430 passes a feedback current through the coil 420 to generate a second magnetic field MF2 based on the magnetic field detection value S. The current detector 440 detects the value of the feedback current flowing through the coil 420. The current detector 440 is, for example, a resistor inserted in the current path of the feedback current. In this case, the potential difference across the resistor corresponds to the detected value of the feedback current. Because the detected value of the feedback current is proportional to the value of the current Itg in the bus bar 410, the value of the current Itg can be detected from the detected value of the feedback current.

[0055] The magnetic sensor device 1 of the present disclosure may be mounted in an electronic device such as an information device and used as a magnetic compass to detect the earth's magnetic field, or may be used as part of an autofocus mechanism or optical image stabilization mechanism of a camera module, or may be used as an angle sensor to detect the angle that the magnetic field generated from a magnet makes with respect to a reference direction, or may be used as part of a current sensor to detect the value of the current flowing through a bus bar.

[0056] Fig. 8 is a perspective view showing an example of a magnetic sensor device 1 used as part of the autofocus mechanism and optical image stabilization mechanism of a camera module 200. Fig. 9 is a cross-sectional view showing the internal structure of the camera module 200 shown in Fig. 8. The autofocus mechanism and optical image stabilization mechanism of the camera module 200 includes a driving device 230 that moves the lens 220, and controls the driving device 230 based on position information of the lens 220 detected by a plurality of magnetic sensor devices 1.

[0057] More specifically, the autofocus mechanism uses an image sensor or autofocus sensor to detect when a subject is in focus, and moves the lens in the Z direction relative to the image sensor. The optical image stabilization mechanism detects camera shake using a gyro sensor or the like, and moves the lens in the U and / or V directions relative to the image sensor.

[0058] The camera module 200 shown in Figure 8 includes an image sensor 210 such as a CMOS, a lens 220 that is aligned with the image sensor 210, a first holding member 241 that is movable in the U and V directions relative to the image sensor 210, a second holding member 242 that is movable in the Z direction relative to the first holding member 241, a plurality of elastically deformable wires 244 that support the first holding member 241 and the second holding member 242, a drive device 230 that moves the first holding member 241 and the second holding member 242, and a housing 250 that houses them.

[0059] The autofocus mechanism and optical image stabilization mechanism of camera module 200 includes a drive device 230, a plurality of magnetic sensor devices 1, a processor that controls drive device 230, an autofocus sensor that detects when the subject is in focus, a gyro sensor that detects camera shake, etc. The processor, autofocus sensor, gyro sensor, etc. (not shown) are arranged outside the housing.

[0060] The lens 220 is fixed inside a cylindrical second holding member 242. The second holding member 242 is housed together with the lens 220 in a box-shaped first holding member 241. At least one second magnet 243 is fixed to the second holding member 242 so that at least one magnetic sensor device 1 detects position information of the second holding member 242.

[0061] The driving device 230 includes a plurality of first coils 231, a plurality of second coils 232, a plurality of first magnets 233, etc. The plurality of first coils 231 are fixed to the housing 250. The plurality of second coils 232 are fixed to the second holding member 242. The plurality of first magnets 233 are fixed to the first holding member 241. Each of the plurality of first coils 231 faces a corresponding first magnet 233. Each of the plurality of second coils 232 faces a corresponding first magnet 233.

[0062] In the case of the autofocus mechanism, when a current flows through any second coil 232 in response to a command from the processor, the second holding member 242 fixed to the second coil 232 moves in the Z direction due to the interaction between the magnetic field generated from the first magnet 233 and the magnetic field generated from the second coil 232. At least one magnetic sensor device 1 generates a detection signal based on a composite magnetic field formed by combining the magnetic field generated from at least one second magnet 243 fixed to the second holding member 242 and the magnetic field generated from the first magnet 233 fixed to the first holding member 241, and transmits the detection signal to the processor. The processor detects position information of the lens 220 in the Z direction from the detection signal, and controls the drive device 230 so that the subject is in focus.

[0063] In the case of an optical image stabilization mechanism, when a current flows through any of the first coils 231 in response to a command from the processor, the magnetic field generated from the first magnet 233 interacts with the magnetic field generated from the first coil 231, causing the first holding member 241 fixed to the first magnet 233 to move in the U direction and / or V direction. Each of the multiple magnetic sensor devices 1 generates a detection signal based on the position of the corresponding first magnet 233 and transmits it to the processor. The processor detects position information of the lens 220 in the U direction and V direction from the detection signal, and controls the drive device 230 to correct camera shake.

[0064] Next, the magnetic sensor device 1 of the present disclosure will be described in detail with reference to Fig. 10A to Fig. 25. Fig. 10A is a plan view of a simulation model in which a hole 11 with a rectangular outline O11 is formed on the first surface 10B of the sensor substrate 10, as viewed from the direction perpendicular to the surface Z, and shows positions P and Q plotted on the top surface 3A of the sensor chip 3.

[0065] As shown in Figure 10A, the position directly above corner C1 of hole 11, which is 280 µm square, is set to P = 0 in both the X-axis and Y-axis directions, and the positions are plotted as P = 1, 2, 3, ..., 14, shifted by 10 µm in each direction along the X-axis and Y-axis. For example, P = 14 is located 140 µm away from P = 0 in both the X-axis and Y-axis directions. Similarly, the position directly above corner C1 is set to Q = 0, and the positions are plotted as Q = 1, 2, 3, ..., 14, shifted by 10 µm in each direction along the X-axis.

[0066] 10B is a plan view, as viewed from the direction perpendicular to the surface Z, of a simulation model in which a rectangular hole 11 with a contour O11 and rounded corners is formed on the first surface 10B of the sensor substrate 10, and shows a position P plotted on the top surface 3A of the sensor chip 3. As shown in Fig. 10B, the position directly above the corner C1 of the hole 11, which is 340 µm square in both the X-axis and Y-axis directions and has rounded corners with a diameter of 200 µm, is set to P=0, and the position is moved by 10 µm in each of the X-axis and Y-axis directions, and plotted as P=1, 2, 3, ... 14.

[0067] 10C is a plan view of a simulation model in which a circular hole 11 is formed in the first surface 10B of the sensor substrate 10, as viewed from the direction perpendicular to the surface Z, and shows a position P plotted on the top surface 3A of the sensor chip 3. As shown in Fig. 10C, the position directly above the outline O11 of the circular hole 11 with a diameter of 400 µm is set to P=0, and the position is moved by 10 µm in each of the X-axis and Y-axis directions, and plotted as P=1, 2, 3, ... 14.

[0068] 10D is a plan view of a simulation model, as viewed from the direction perpendicular to the surface Z, in which the model shown in FIG. 10A is further provided with wiring layers 4 each 100 μm square in the X-axis direction and the Y-axis direction. The wiring layers 4 are arranged so that their centers are at the position P=0. In the simulation results of FIG. 15, which will be described later, similar to FIG. 10D, the models shown in FIGS. 10B and 10C also include wiring layers 4 each 100 μm square in the X-axis direction and the Y-axis direction, each centered at the position P=0.

[0069] 10E is a plan view of a simulation model having an inner surface 11C inclined relative to the plane-normal direction Z, as viewed from the plane-normal direction Z, and shows a position P plotted on the upper surface 3A of the sensor chip 3. As shown in FIG. 10E, the simulation model has a hole 11 that is 400 μm square in each of the X-axis and Y-axis directions, has a deepest center depth D of 15 μm as shown in FIG. 11 (described later), has no bottom surface 10D, and instead has an inclined or stepped inner surface 11C. In this simulation model, the wiring layer 4 shown in FIG. 10D is added so as to overlap the hole 11, and the position directly below the center of the wiring layer 4 is set to P=0. The position is shifted by 10 μm in each of the X-axis and Y-axis directions, and plotted as P=1, 2, 3, ... 14.

[0070] 11 is a cross-sectional view of the simulation model taken along an XY plane perpendicular to the plane-normal direction Z. The outline O11 of the hole 11 is the outline of the bottom surface 11D of the hole 11, and is defined by the boundary between the bottom surface 11D and the inner surface 11C. The boundary between the bottom surface 11D and the inner surface 11C may have a corner R. In this case, if the bottom surface 11D is flat and the depth D from the first surface 10B to the bottom surface 11D is approximately constant, the position where the gradual decrease in the depth D begins is the boundary between the bottom surface 11D and the inner surface 11C.

[0071] 12 to 16, the thickness T from the first surface 10B to the second surface 10A of the sensor substrate 10 is 15 μm, and the thickness of the functional film 20 is also 15 μm. In the simulation results of Fig. 15, the distance from the upper surface 3A of the sensor chip 3 to the lower surface of the wiring layer 4 is 5 μm.

[0072] Figure 12 is a graph showing the simulated angular error at each of the depths D shown in Figure 11 at the position P shown in Figure 10A, where the position P shown in Figure 10A is changed to 15 patterns from 0 to 14, and the depth D from the first surface 10B of the sensor substrate 10 shown in Figure 11 to the bottom surface 11D of the hole 11 is changed to four patterns of 0 μm, 5 μm, 7.5 μm, and 15 μm, and the simulation results of the angular error when a predetermined stress value is applied to the magnetic sensor device 1 are plotted on the vertical axis.

[0073] When the depth D is less than 15 μm, the hole 11 is formed as a bottomed hole recessed from the first surface 10B toward the second surface 10A of the sensor substrate 10. When the depth D is 15 μm, the hole 11 is formed as a through hole penetrating from the first surface to the second surface. Even when the hole 11 is a through hole, the magnetic detection element E is fixed by the functional film 20 that surrounds the magnetic detection element E.

[0074] 12, the closer P is to 0, the larger the angle error becomes. If the magnetic detection element E is located directly above the corner C1, it is susceptible to the influence of thermal stress from the sensor substrate 10. In the in-plane direction perpendicular to the plane-normal direction Z, each of the magnetic detection elements E is preferably arranged at a distance of 10 μm or more from each of the corners C1 to C4. Furthermore, the angle error increases as the depth D of the hole 11 increases. The depth D of the hole 11 is preferably equal to or less than half the thickness T of the sensor substrate 10 (T=30 μm).

[0075] Figure 13 is a graph showing the simulated angular error at each of the depths D shown in Figure 11 at the position Q shown in Figure 10A, with the horizontal axis plotting the simulation results of the angular error when a predetermined stress value is applied to the magnetic sensor device 1, with the position Q shown in Figure 10A being changed to 14 patterns from 1 to 14 and the depth D of the hole 11 shown in Figure 11 being changed to four patterns of 0 μm, 5 μm, 7.5 μm, and 15 μm.

[0076] As shown in FIG. 13, the closer to Q=0 (the same value as the plot of P=0 shown in FIG. 12), the larger the angle error. If the magnetic detection element E is located directly above the corner C1, it is susceptible to the effects of thermal stress from the sensor substrate 10. Whether it is P moving away from the contour O11 of the hole 11 or Q moving on the contour O11 of the hole 11, there is a common tendency for the angle error to increase as it approaches the corner C1.

[0077] Figure 14 shows the simulated angle error when the depth D of the hole 11 is fixed at 15 μm and the position P shown in Figures 10A, 10B, and 10C is changed to 15 patterns from 0 to 14 and a predetermined stress value is applied to the magnetic sensor device 1.

[0078] 14, the angle error tends to increase in the order of the model in which the contour O11 of the hole 11 is a square with rounded corners, the circular model, and the square model. In all models, the angle error increases as P approaches 0. If the magnetic detection element E is located directly above the corner C1, it is susceptible to the influence of thermal stress from the sensor substrate 10.

[0079] Figure 15 shows the simulated angle error when a predetermined stress value is applied to the magnetic sensor device 1 while the depth D of the hole 11 is fixed at 15 μm, the wiring layer 4 shown in Figure 10D is added, and the position P shown in Figures 10A, 10B, and 10C is changed to 15 patterns from 0 to 14.

[0080] 14 and 15, the model with the wiring layer 4 tends to have smaller angle errors than the model without the wiring layer 4 at positions P=0 to 3 inside the contour O4 of the wiring layer 4, regardless of whether the contour O11 of the hole 11 is a rectangle, a rectangle with a rounding, or a circle. In other words, it can be expected that the sensor substrate 10 will be less susceptible to the effects of thermal stress. However, in the rectangular model, the model with the wiring layer 4 has larger angle errors than the model without the wiring layer 4 at positions P=4 to 6 near the contour O4 of the wiring layer 4.

[0081] 16 shows simulated angular errors when a predetermined stress value is applied to the magnetic sensor device 1 while changing P shown in FIG. 10E among 15 patterns from 0 to 14. Comparing the simulation results of FIG. 15 and FIG. 16, both the model in which the inner surface 11C is inclined with respect to the direction perpendicular to the surface Z and the model in which the inner surface 11C is formed in a stepped shape have larger angular errors than the model in which the inner surface 11C is not inclined. In other words, they tend to be more susceptible to the influence of thermal stress from the sensor substrate 10.

[0082] Preferred examples of the present disclosure will be described with reference to FIGS. 17 to 25. As described above with reference to FIGS. 12 to 15, the angle error increases as the angle approaches the corners C1 to C4. If the magnetic detection element E is located directly above the corners C1 to C4, it is susceptible to thermal stress from the sensor substrate 10. FIGS. 17 to 20 are plan views showing first to fourth examples in which all the magnetic detection elements are arranged so as not to overlap the contours of the hole portions. All the magnetic detection elements E are arranged so as not to overlap the contour O11 of the hole portion 11. In the first to fourth examples, each of the multiple magnetic detection elements E does not overlap any of the corners C1 to C4 of the contour O11 of the hole portion 11 in a plan view, and therefore the magnetic detection element E is less susceptible to thermal stress from the sensor substrate 10.

[0083] 17, in a plan view, some of the multiple magnetic detection elements E are arranged inside the outline O11 of the hole 11, and the rest of the multiple magnetic detection elements E are arranged outside the outline O11 of the hole 11. In other words, in the first example shown in FIG. 17, the magnetic detection elements are arranged straddling the inside and outside of the outline O11.

[0084] As in the second example shown in Fig. 18, the hole 11 may be arranged across multiple bridge circuits. In the examples shown in Fig. 17 to Fig. 24, the magnetic sensor device 1 includes first to fourth magnetic detection element arrays 31, 32, 33, and 34, and a first bridge circuit is formed by two parallel circuits. In the second example shown in Fig. 18, the magnetic sensor device 1 further includes fifth to eighth magnetic detection element arrays 35, 36, 37, and 38, and a second bridge circuit is formed by two parallel circuits.

[0085] The first and second magnetic detection element arrays 31 and 32 are connected in series across output port A to form one parallel circuit of a first bridge circuit, while the third and fourth magnetic detection element arrays 33 and 34 are connected in series across output port B to form the other parallel circuit of the first bridge circuit. Similarly, the fifth and sixth magnetic detection element arrays 35 and 36 are connected in series across output port A to form one parallel circuit of a second bridge circuit, while the seventh and eighth magnetic detection element arrays 37 and 38 are connected in series across output port B to form the other parallel circuit of the second bridge circuit. The output ports A and B are connected to a galvanometer or the like. In the second example shown in FIG. 18, similar to the first example, magnetic detection elements are arranged across the inside and outside of the contour O11.

[0086] In the magnetic sensor device 1 of the present disclosure, all of the magnetic detection elements E may be arranged inside the contour O11 in a planar view, as in a third example shown in Fig. 19, or all of the magnetic detection elements E may be arranged outside the contour O11 in a planar view, as in a fourth example shown in Fig. 20. The magnetic sensor device 1 of the present disclosure has few restrictions on the arrangement of the magnetic detection elements E, allowing for excellent design freedom.

[0087] 21 to 23 are plan views showing fifth to seventh examples in which the first magnetic detection element E1 is arranged to overlap the contour O11 of the hole 11 at a location other than the corners C1 to C4, and the second magnetic detection element E2 is arranged not to overlap the contour O11 of the hole 11. The positions that overlap the contour O11 of the hole 11 at a location other than the corners C1 to C4 are slightly more susceptible to thermal stress than the positions that do not overlap the contour O11, but the influence of thermal stress is sufficiently smaller than the positions that overlap the corners C1 to C4. In the fifth to seventh examples, none of the multiple magnetic detection elements E overlaps any of the corners C1 to C4 of the contour O11 of the hole 11 in a plan view. Therefore, the magnetic detection elements E (the first magnetic detection element E1 and the second magnetic detection element E2) are less susceptible to thermal stress from the sensor substrate 10.

[0088] In the magnetic sensor device 1 of the present disclosure, the second magnetic detection elements E2 that do not overlap the contour O11 of the hole 11 may be arranged straddling the inside and outside of the contour O11 in plan view, as in the fifth example shown in Fig. 21, or the entire second magnetic detection elements E2 may be arranged inside the contour O11 in plan view, as in the sixth example shown in Fig. 22, or the entire second magnetic detection elements E2 may be arranged outside the contour in plan view, as in the seventh example shown in Fig. 23. The magnetic sensor device 1 of the present disclosure has few restrictions on the arrangement of the magnetic detection elements E, allowing for excellent design freedom.

[0089] FIG. 24 is a plan view showing an eighth example in which a wiring layer 4 is added to the first example shown in FIG. 17 so that the magnetic detection elements E are disposed inside the outline O4 of the wiring layer 4. In the eighth example, similar to the first example, in a plan view, each of the magnetic detection elements E does not overlap any of the corners C1 to C4 of the outline O11 of the hole 11. Therefore, the magnetic detection elements E are less susceptible to the influence of thermal stress from the sensor substrate 10. As described with reference to FIG. 15, adding the wiring layer 4 reduces the angle error inside the outline O4 of the wiring layer 4. In the eighth example, it is expected that the influence of thermal stress will be even smaller than in the first example.

[0090] 25 is a cross-sectional view showing a ninth example in which the magnetic detection elements are arranged so as not to overlap the inclined inner surface. As described with reference to FIG. 16, when there is an inner surface 11C inclined with respect to the plane-perpendicular direction Z, the position overlapping the inner surface 11C in plan view tends to be susceptible to the influence of thermal stress from the sensor substrate 10. In the ninth example, each of the multiple magnetic detection elements E does not overlap the inclined inner surface 11C, and therefore the magnetic detection elements E are less susceptible to the influence of thermal stress from the sensor substrate 10.

[0091] According to the magnetic sensor device 1 of the present disclosure configured as described above, since the hole 11 is formed in the sensor substrate 10, the amount of adhesive AD that overflows from the first surface 10B of the sensor substrate 10 is less likely to change even if the amount of adhesive AD applied changes, compared to when the hole 11 is not formed. The adhesive layer becomes thicker and the adhesive strength is improved. Therefore, the sensor substrate 10 can be adhered and suitably fixed to the support substrate 2. In plan view, the positions of the outline O11 of the hole 11 that overlap with the corners C1 to C4 are susceptible to the influence of thermal stress. However, since each of the multiple magnetic detection elements E does not overlap with any of the corners C1 to C4, it is less susceptible to the influence of thermal stress. A magnetic sensor device 1 with stable output characteristics of the magnetic detection element array can be provided.

[0092] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those illustrated and can be modified as appropriate. Furthermore, configurations shown in different embodiments can be partially substituted or combined with each other. [Explanation of symbols]

[0093] 1...magnetic sensor device, 2...support substrate, 2A...upper surface, 2B...lower surface, 2E...electrode, 3...sensor chip, 3A...upper surface, 3E...electrode, 3X...first sensor chip, 3Y...second sensor chip, 3Z...third sensor chip, 4...wiring layer, 5...sealing resin, 6...electrode, 6P...through hole, 10...sensor substrate, 10A...second surface (upper surface), 10B...first surface (lower surface), 11...hole portion (bottomed hole or through hole), 11C...inner surface of hole portion (inner wall surface), 11D...bottom surface of hole, 20...functional film, 30...magnetic detection element array, 31-38...first to eighth magnetic detection element arrays, 40...via, 40P...through hole, 41...first wiring layer, 42...second wiring layer, 51-53...resin layer, 200...camera module, 210...image sensor, 220...lens, 230...driver, 231...first coil, 232...second coil, 233...first magnet, 241...second First holding member, 242...second holding member, 243...second magnet, 244...wire, 250...casing, 300...magnet, 400...current sensor, 410...bus bar, 420...coil, 430...feedback circuit, 440...current detector 440, A...output port, AD...adhesive, B...output port, C1, C2, C3, C4...corner, D...hole depth, DR...reference direction, E...magnetic detection element, E1...first magnetic detection element element, E2...second magnetic detection element, Itg...current, L1...first layer, L2...second layer, MF...magnetic field, MF1...first magnetic field, MF2...second magnetic field, O...central axis, O4...outline of wiring layer, O11...outline of hole, P, Q...position, S...magnetic field detection value, T...thickness of sensor board, U, V...direction of hand movement, W...wiring, X...left-right direction (an example of an in-plane direction), Y...front-back direction (another example of an in-plane direction), Z...direction perpendicular to the plane, θ...angle.

Claims

1. A support substrate; a sensor substrate fixed to the support substrate, the sensor substrate has a first surface facing the support substrate and a second surface located opposite to the first surface, the second surface having a functional film including a plurality of magnetic detection elements; A hole is formed in the first surface, The contour of the hole includes at least one corner; each of the plurality of magnetic detection elements is arranged so as not to overlap any of the at least one corner in a plan view seen along a direction perpendicular to the surface from the second surface toward the first surface; Magnetic sensor device.

2. the sensor substrate is fixed to the support substrate using an adhesive; The hole is filled with the adhesive. The magnetic sensor device according to claim 1 .

3. Each of the plurality of magnetic detection elements is arranged so as not to overlap the contour in the plan view. The magnetic sensor device according to claim 1 .

4. some of the plurality of magnetic detection elements are arranged inside the outline in the plan view, and the remainder of the plurality of magnetic detection elements are arranged outside the outline in the plan view; The magnetic sensor device according to claim 3 .

5. All of the plurality of magnetic detection elements are arranged inside the outline in the plan view. The magnetic sensor device according to claim 3 .

6. All of the plurality of magnetic detection elements are arranged outside the outline in the plan view. The magnetic sensor device according to claim 3 .

7. the plurality of magnetic detection elements include at least one first magnetic detection element arranged so as to overlap the contour in the plan view; The magnetic sensor device according to claim 1 .

8. the plurality of magnetic detection elements further include a plurality of second magnetic detection elements arranged so as not to overlap the contour in the plan view, some of the second magnetic detection elements are arranged inside the outline in the plan view, and the remainder of the second magnetic detection elements are arranged outside the outline in the plan view. The magnetic sensor device according to claim 7 .

9. the plurality of magnetic detection elements further include at least one second magnetic detection element arranged so as not to overlap the contour in the plan view, the at least one second magnetic detection element is entirely disposed inside the outline in the plan view; The magnetic sensor device according to claim 7 .

10. the plurality of magnetic detection elements further include at least one second magnetic detection element arranged so as not to overlap the contour in the plan view, the at least one second magnetic detection element is entirely disposed outside the outline in the plan view; The magnetic sensor device according to claim 7 .

11. the hole portion is a bottomed hole recessed from the first surface toward the second surface, The depth of the bottomed hole is equal to or less than half the thickness of the sensor substrate in the direction perpendicular to the surface. The magnetic sensor device according to claim 1 .

12. a wiring layer provided in a layer farther from the support substrate than the functional film in the perpendicular direction, Each of the plurality of magnetic detection elements is disposed inside the outline of the wiring layer in the plan view. The magnetic sensor device according to claim 1 .

13. The hole has an inner surface inclined with respect to the plane perpendicular direction, Each of the plurality of magnetic detection elements is arranged so as not to overlap with the inner surface in the plan view. The magnetic sensor device according to claim 1 .

14. A magnetic sensor device comprising: Angle sensor.

15. A magnetic sensor device comprising: Magnetic compass.

16. A magnetic sensor device comprising: Current sensor.

17. An autofocus mechanism and / or an optical image stabilization mechanism including the magnetic sensor device according to claim 1. Camera module.

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