JP2020047898A - Magnetic sensor - Google Patents

Abstract

To improve sensibility of magnetic sensor furthermore.SOLUTION: A magnetic sensor 200 has four contact parts 51-54 penetrating an insulator film 40 and electrically connecting electrode parts 31-34 and a magneto-sensitive part 20 at a position becoming the vertex of a square in the plan view, and out of two sets consisting of two contact parts existing on the diagonal lines of the square, the contact parts included in one set have larger areas, in the plan view, than those of the contact parts included in the other set. In the plan view, the sides of a substrate 10 are arranged in parallel with the sides of the magnetic sensor 200, lead terminals 211-214 are arranged at four corners of the magnetic sensor 200, and the angle formed by segments L1-L4 connecting between the contact parts with the shortest distance, and a diagonal line L6 or L7 corresponding to the segments L1-L4 of a square L5 formed by connecting points on the contact parts corresponding to the segments L1-L4, is set less than 30 degrees.SELECTED DRAWING: Figure 3A

Description

  The present invention relates to a magnetic sensor.

  Conventionally, a magnetic sensing part, an insulating film, and an electrode are laminated in this order on one surface side of a substrate, and the magnetic sensing part and the electrode are electrically connected by a contact part through an opening formed in the insulating film. In order to improve the S / N ratio, a Hall element has been proposed (for example, see Patent Document 1).

International Publication No. WO 2017/051829

Incidentally, the Hall element described in Patent Document 1 has room for improvement in sensitivity.
Therefore, the present invention has been made in view of the above-mentioned conventional unsolved problems, and has as its object to provide a high-sensitivity magnetic sensor using a Hall element.

  In order to achieve the above object, a magnetic sensor according to one embodiment of the present invention includes an element portion, four lead terminals, and a sealing member that seals the element portion and the lead terminal, A rectangular magnetic sensor in a plan view, wherein the element portion is formed on a substrate formed in a rectangular shape in plan view, a magnetic sensing portion formed on the substrate, and formed on the magnetic sensing portion. An insulating film, four electrode portions formed on the insulating film and each connected to the lead terminal, and provided at a position corresponding to each of the electrode portions to be a vertex of a square in plan view, And four contact portions that penetrate a film and electrically connect the electrode portion and the magneto-sensitive portion, and a region surrounded by the rectangle is all included in the magneto-sensitive portion in plan view. And two sets formed by two contact portions existing on a diagonal line of the square. Of these, each area in plan view of the two contact portions included in one set is larger than each area in plan view of the two contact portions included in the other set, and in plan view, the side of the substrate is the magnetic side. The four lead terminals are arranged so as to be parallel to the sides of the sensor, and the four lead terminals are respectively arranged at the four corners of the magnetic sensor, and each of the four lead terminals is connected to one of the lead terminals in plan view. A rectangular segment formed by connecting a line segment connecting the contact portion and the one lead terminal at the shortest distance between the contact portion connecting the electrode portion to the magnetic sensing portion and a point on the contact portion of the line segment. An angle at which a diagonal line intersects with a diagonal line passing through a point on the contact portion of the line segment is less than 30 degrees.

  According to one embodiment of the present invention, a Hall element capable of obtaining a larger output voltage with a small output voltage fluctuation can be realized.

It is a top view showing an example of the hall element applied to the magnetic sensor concerning one embodiment of the present invention. It is AA 'sectional drawing of FIG. 1A. It is BB 'sectional drawing of FIG. 1A. It is a top view showing an example of a magnetic sensor. It is the schematic which shows an example of the cross section of a magnetic sensor. FIG. 4 is an explanatory diagram for explaining an effect of the magnetic sensor according to one embodiment of the present invention. FIG. 4 is an explanatory diagram for explaining an effect of the magnetic sensor according to one embodiment of the present invention.

In the following detailed description, numerous specific specific configurations are set forth in order to provide a thorough understanding of embodiments of the present invention. However, it is clear that other embodiments can be implemented without being limited to such specific specific configurations. Further, the following embodiments do not limit the invention according to the claims, but include all combinations of characteristic configurations described in the embodiments.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same portions are denoted by the same reference numerals. However, the drawings are schematic, and the relationship between the thickness and the plane dimension, the ratio of the thickness of each layer, and the like are different from actual ones.

  A magnetic sensor according to an embodiment of the present invention is a rectangular magnetic sensor in plan view, including an element portion, four lead terminals, and a sealing member that seals the element portion and the lead terminal. The element portion includes a substrate formed in a rectangular shape in a plan view, a magnetically sensitive portion formed on the substrate, an insulating film formed on the magnetically sensitive portion, and an insulating film formed on the insulating film. Four electrode portions connected to the lead terminals, and provided at positions corresponding to the vertices of a square in plan view corresponding to each of the electrode portions, penetrate the insulating film and electrically connect the electrode portion and the magnetic sensing portion. And four contact portions to be connected, and a region surrounded by the rectangle is all included in the magnetosensitive portion in plan view, and two regions formed by two contact portions existing on a diagonal line of the rectangle. The area of each of the two contact portions included in one of the sets in plan view is the other set. The two contact portions included are larger than the respective areas in plan view, and the sides of the substrate are arranged so as to be parallel to the sides of the magnetic sensor in plan view, and the four lead terminals are respectively arranged at the four corners of the magnetic sensor. For each of the four lead terminals, in plan view, a line connecting the contact portion connecting the electrode portion connected to one lead terminal to the magneto-sensitive portion and the shortest distance between the one lead terminal, and this line segment The angle at which a diagonal of a quadrangular diagonal formed by connecting points on the contact portion with a diagonal passing through a point on the contact portion of this line intersects is less than 30 degrees.

[Embodiment]
FIG. 1A is a plan view showing an example of a Hall element 100 according to one embodiment of the present invention. FIG. 1B is a cross-sectional view taken along the line AA ′ of FIG. 1A. FIG. 1C is a cross-sectional view taken along the line BB ′ of FIG. 1A.
The Hall element 100 according to one embodiment of the present invention includes a substrate 10, a magnetic sensing unit 20, electrode units 31 to 34, an insulating film 40, and contact units 51 to 54. The magnetic sensing unit 20 includes a conductive layer 21 and a surface layer 22.

The substrate 10 is a semiconductor substrate such as Si or a compound semiconductor. The substrate 10 according to one embodiment of the present invention is, for example, a GaAs substrate. The resistivity of the substrate (GaAs substrate) 10 is 1.0 × 10 ⁵ Ω · cm or more. The upper limit of the resistivity of the substrate 10 may be 1.0 × 10 ⁹ Ω · cm or less. The substrate 10 has, for example, a substantially square planar shape. The planar shape of the substrate 10 is not limited to a substantially square shape, but may be any rectangular shape.
The magnetic sensing part 20 is formed on the substrate 10. The magneto-sensitive portion 20 may be formed on the substrate 10 and partially embedded in the substrate 10. The magnetic sensing part 20 has a substantially square planar shape. The magnetic sensing part 20 is a layer having a lower resistance than the substrate 10. The magnetic sensing part 20 is formed of a compound semiconductor such as GaAs, InSb, and InAs. The magnetic sensing part 20 according to one embodiment of the present invention is formed of GaAs. Further, the magnetic sensing unit 20 may be activated by injecting impurities such as Si, Sn, S, Se, Te, Ge and C into the substrate 10 and heating the same.

  In addition, the magnetic sensing unit 20 may have a planar shape in which at least one corner is rounded. At the end of the magnetic sensing unit 20, the current flowing through the Hall element 100 may be concentrated. Since the planar shape of the magnetic sensing unit 20 is rounded, current concentration at the end of the magnetic sensing unit 20 is reduced. This effect is remarkable when the magneto-sensitive portion 20 is formed in a step shape (mesa shape) on the substrate 10. In particular, it is preferable that the corners of the magneto-sensitive portion 20 have a radius of curvature of 10% or more with respect to the thickness of the magneto-sensitive portion 20, since current concentration at the end of the magneto-sensitive portion 20 can be reduced. Further, it is preferable to have a radius of curvature of 10000% or less with respect to the thickness of the magneto-sensitive portion 20 in that the fluctuation of the output voltage of the Hall element 100 can be suppressed. This is presumed to be due to the fact that it is possible to reduce the exposure of the surface other than the smallest surface (for example, the (100) surface) of the dangling bond on the side surface of the magneto-sensitive portion 20, and it becomes difficult for the surface recombination of carriers to occur. Is done.

  The magnetic sensing unit 20 is not limited to a substantially square. It is only necessary that the four contact portions 51 to 54 be arranged at positions corresponding to the vertices of the quadrangle, and that the entire region surrounded by the contact portions 51 to 54 be included in the magnetosensitive portion 20. By forming the magneto-sensitive portion 20 in a substantially square shape or a shape in which the entire region surrounded by the four contact portions 51 to 54 is included in the magneto-sensitive portion 20, it is possible to make the shape less likely to cause current concentration. Further, the area of the magnetic sensing unit 20 with respect to the substrate 10 can be maximized. This is preferable in that 1 / f noise can be suppressed and fluctuations in the output characteristics of the Hall element 100 can be suppressed.

  As long as the entire region surrounded by the four contact portions is included in the magnetic sensing portion 20, the magnetic sensing portion 20 may extend outside the region surrounded by the four contact portions. For example, the edge of the magnetic sensing unit 20 may not be a straight line, and a notch or the like may be formed in the edge of the magnetic sensing unit 20. On the other hand, the notch formed at the edge of the magneto-sensitive portion 20 is relatively large, and the entire area surrounded by the four contact portions 51 to 54 is not included in the magneto-sensitive portion 20 (so-called so-called “sensitive” portion). In the case of a cross shape, current concentration is likely to occur near the notch (ie, at the intersection of the cross). Therefore, 1 / f noise may increase.

  The region surrounded by the four contact portions 51 to 54 can be determined as follows. First, the center of gravity of the magnetic sensing unit 20 in plan view is set as the center of the magnetic sensing unit 20. Next, a point at which the distance between the center of the magnetic sensing part 20 and each of the contact portions 51 to 54 is minimized is drawn on each of the contact portions 51 to 54. A region formed by connecting these points is defined as a region surrounded by the four contact portions 51 to 54. When there are a plurality of points in each contact portion where the distance from the center of the magneto-sensitive portion 20 is minimum, a region connecting all these points is surrounded by the four contact portions 51 to 54. Area. In addition, when there is a contact part that is not used for both input and output, the above-described region may be determined without considering the contact part.

The conductive layer 21 is formed on the substrate 10. The conductive layer 21 according to one embodiment of the present invention is n-type GaAs. The thickness of the conductive layer 21 is not particularly limited. The thickness of the conductive layer 21 according to one embodiment of the present invention is 50 nm or more and 2000 nm or less. The thickness of the conductive layer 21 may be 100 nm or more and 1000 nm or less.
The surface layer 22 is formed of a conductive material on the conductive layer 21. The surface layer 22 is made of a GaAs layer having lower conductivity than the conductive layer 21 or a high-resistance crystal such as AlGaAs or AlAs. The thickness of the surface layer 22 according to one embodiment of the present invention is 150 nm or more. The thickness of the surface layer 22 may be 200 nm or more. The upper limit of the thickness of the surface layer 22 may be 800 nm or less, or 600 nm or less. In addition, the surface layer 22 may not be formed on the magnetically sensitive portion 20.

The insulating film 40 is formed so as to cover the upper surface of the magnetic sensing unit 20 and the side surface of the magnetic sensing unit 20. The insulating film 40 according to one embodiment of the present invention is formed so as to cover the entire surface layer 22 and the entire side surface of the stacked body of the conductive layer 21 and the surface layer 22.
The insulating film 40 has a contact opening 40a. The thickness of the insulating film 40 is, for example, 100 nm or more, but is not limited thereto. The insulating film 40 is, for example, a silicon nitride film (Si ₃ N ₄ film), a silicon oxide film (SiO ₂ film), an alumina film (Al ₂ O ₃ ), a polyimide film, and a multilayer in which at least one of these films is laminated. It is a membrane. In the plan view shown in FIG. 1A, the insulating film 40 is omitted for simplification.

The electrode portions 31 to 34 are formed on the insulating film 40. For example, the electrode unit 31 and the electrode unit 32 are input electrode units (input electrode units) for flowing a current through the magnetic sensing unit 20, and the electrode unit 33 and the electrode unit 34 are holes of the magnetic sensing unit 20. An output electrode unit (output electrode unit) for detecting a voltage.
The electrode portions 31 to 34 are electrically connected to the magneto-sensitive portion 20 via the contact portions 51 to 54 through the openings 40 a provided in the insulating film 40. The electrode portions 31 to 34 are formed of a conductive material such as metal or polysilicon. The electrode portions 31 to 34 in one embodiment of the present invention contain gold as a main component.

The electrode portions 31 to 34 are formed on the corresponding contact portions 51 to 54, respectively. As will be described later, the contact portions 51 to 54 are arranged at positions corresponding to the vertices of a substantially square. Therefore, the electrode portions 31 to 34 disposed on the contact portions 51 to 54 also have the vertices of a substantially square. It will be arranged in the position which becomes.
The electrode portions 31 to 34 extend in a direction approaching the diagonally opposed electrode portions and in a direction approaching each of the two adjacent electrode portions when viewed from the corresponding contact portions 51 to 54 as base points. Formed out. The electrode portions 31 to 34 according to an embodiment of the present invention have, for example, a substantially square planar shape, and at this time, of the four corner portions of the substantially square shape, the corners of the magneto-sensitive portion 20 in plan view. The three corners except for the corner overlapping the part have a shape in which the corner is cut off obliquely.

The electrode units 31 to 34 are arranged such that each side of the electrode units 31 to 34 and each side of the magnetic sensing unit 20 are parallel to each other. Further, the outer periphery of each of the electrode portions 31 to 34 is located inside a region surrounded by the outer periphery of the magnetic sensing portion 20 in a plan view. The sizes of the electrode portions 31 to 34 will be described later.
Here, in the case where the electrode portions 31 to 34 are formed above the magnetically sensitive portion 20, the magnetically sensitive portion 20 can suppress the influence of chipping because at least one corner is rounded. it can.

  That is, dicing is performed when the substrate 10 is separated into individual pieces. However, when the electrode portions 31 to 34 are not arranged between the outer peripheral portion of the substrate 10 and the outer peripheral portion of the magneto-sensitive portion 20, the dicing is performed by chipping. There is a case where the magnetic portion 20 is chipped, causing current concentration due to the chipping. In particular, when the corners of the magneto-sensitive portion 20 are not rounded, the stress from the insulating film 40 and the stress at the time of dicing may concentrate on the corner of the magneto-sensitive portion, and may become a starting point of a crack. When at least one corner of the magnetically sensitive portion 20 is rounded, current concentration can be reduced by relaxing the stress and the like and suppressing chipping of the end of the magnetically sensitive portion 20 due to chipping.

  The electrode portions 31 to 34 according to one embodiment of the present invention are formed in the region of the magnetic sensing portion 20 in plan view, but at least a part of these electrode portions is formed in the magnetic sensing portion 20 in plan view. It may extend to outside the region of 20. It is preferable that the electrode portions 31 to 34 be formed in the region of the magnetic sensing portion 20 in a plan view, since the fluctuation of the output voltage of the Hall element 100 can be reduced. This is because the stress due to the difference in the coefficient of thermal expansion between the magnetic sensing portion 20 and the electrode portions 31 to 34 is less likely to be applied to the magnetic sensing portion 20.

  The contact portions 51 to 54 are formed on the magnetic sensing portion 20. The contact portions 51 to 54 according to the embodiment of the present invention penetrate the insulating film 40 and electrically connect the electrode portions 31 to the electrode portions 34 to the magneto-sensitive portion 20. In one embodiment of the present invention, the contact portions 51 to 54 are formed at positions that are substantially square vertices. In addition, the arrangement positions of the contact portions 51 to 54 are not limited to positions that are substantially square vertices, and may be any positions that are square vertices.

The electrode portions 31 to 34 are formed on the contact portions 51 to 54.
The contact portions 51 to 54 according to the embodiment of the present invention are formed of, for example, the same material as the electrode portions 31 to 34. The electrode part 31 to the electrode part 34 and the contact part 51 to the contact part 54 may be formed integrally. The contact portions 51 to 54 may be formed of a different material from the electrode portions 31 to 34.

  The contact portions 51 to 54 have a planar shape corresponding to the planar shape of the magnetically sensitive portion 20, and have a size capable of electrically connecting the magnetically sensitive portion 20 and each of the electrode portions 31 to the electrode portion 34. It is formed. The planar shapes of the contact portions 51 to 54 are the same as the input contact portions 51 and 52 overlapping the input electrode portions 31 and 32 in plan view, and the output electrode portions 33 and 34 in plan view. Although the output contact portions 53 and 54 that overlap with are the same, the input contact portions 51 and 52 and the output contact portions 53 and 54 have different areas. For example, the contact portion 51 to the contact portion 54 have a substantially triangular shape similar to a corner portion of the magnetic sensing portion 20, and three vertexes of the contact portions 51 to 54 vertically oppose an area outside the apex of the magnetic sensing portion 20, Two of the three sides are formed so as to be parallel to the two sides of the magnetic sensing unit 20. However, the area of the input contact parts 51 and 52 is larger than that of the output contact parts 53 and 54. large. The input contact portions 51 and 52 may not necessarily have the same area, and similarly, the output contact portions 53 and 54 may not necessarily have the same area. It is sufficient that each area is larger than each area of the output contact portions 53 and 54.

  In addition, the planar shape of the contact portions 51 to 54 may have a round shape in at least a part of an outer region corresponding to the outer peripheral side of the magnetic sensing portion 20. Further, the planar shape of the contact portions 51 to 54 may have a round shape in an inner region on the center side of the magnetic sensing portion 20, and may have, for example, a fan shape as a whole. As a result, current concentration at the ends of the contact portions 51 to 54 is reduced. The planar shape of the contact portions 51 to 54 is not limited to a fan shape and may be another shape as long as current concentration at the end portions of the contact portions 51 to 54 can be reduced. Note that the outer region here refers to a region that is the outer periphery of the contact portions 51 to 54 and faces the outer periphery of the magnetic sensing portion 20. On the other hand, the inner region refers to a region on the center side of the magnetic sensing unit 20 other than the outer region. In addition, when the entire region surrounded by the four contact portions 51 to 54 is included in the magnetic sensing portion 20, the amount of current flowing particularly to the ends of the contact portions 51 to 54 increases. Thus, the current concentration reducing effect can be obtained.

FIG. 2A is a plan view showing an example of a magnetic sensor 200 using the Hall element 100 according to one embodiment of the present invention. FIG. 2B is a schematic diagram illustrating an example of a cross-sectional view of the magnetic sensor 200.
The magnetic sensor 200 is formed in a rectangular shape in plan view. FIG. 2A shows a case where the magnetic sensor 200 is formed in a rectangular shape in plan view. The magnetic sensor 200 includes a Hall element 100, lead terminals 211 to 214, a protective layer 220, a sealing member 230, an outer plating layer 240, and bonding wires 251 to 254.
As shown in FIG. 2A, the Hall element 100 is arranged such that each side of the substrate 10 of the Hall element 100 is parallel to each side of the magnetic sensor 200 in plan view. Further, the lead terminals 211 to 214 are arranged at four corners of the magnetic sensor 200. Although FIG. 2A illustrates a case where the electrode units 31 and 34 and the electrode units 32 and 33 are arranged so as to be arranged in the longitudinal direction of the magnetic sensor 200, the orientation of the magnetic sensor 200 and the Hall element 100 is arbitrary. Can be set to

Hall element 100 is connected to lead terminals 211 to 214 by bonding wires 251 to 254. The electrode section 31 is electrically connected to the lead terminal 211 by a bonding wire 251. Electrode portion 32 is electrically connected to lead terminal 212 by bonding wire 252. The electrode portion 33 is electrically connected to the lead terminal 213 by a bonding wire 253. The electrode portion 34 is electrically connected to the lead terminal 214 by a bonding wire 254.
The bonding wires 251 to 254 are formed of a conductive material. As the bonding wires 251 to 254, for example, a gold wire can be used, but it is not limited thereto. The bonding wires 251 to 254 are covered with the sealing member 230. As a result, the bonding wires 251 to 254 are fixed.

  A ball portion may be provided between each of the electrode portions 31 to 34 and each of the bonding wires 251 to 254. The ball portion is formed of a conductive material. The ball portion may be formed of the same material as the bonding wires 251 to 254. The ball portion is, for example, a gold ball or a solder ball. In one example, the ball portion has a diameter of 10 μm or more and 100 μm or less in plan view, for example, a diameter of 60 μm. When the ball portion is not a perfect circle in plan view, it may be approximated to an ellipse having the same area as the ball portion in plan view, and the major axis of the ellipse may be the diameter. The thickness of the ball portion is preferably 5 μm or more from the viewpoint of stress relaxation. Further, the thickness of the ball portion is preferably 100 μm or less from the viewpoint of ease of production. Note that the thickness of the ball portion is the distance between the highest portion of the ball portion and the electrode portions 31 to 34 on which the ball portion is arranged.

Here, when observing a cross-sectional transmission diagram obtained by X-ray imaging of the magnetic sensor 200, when the bonding wire 252 is traced from the lead terminal 212 side to the Hall element 100 side, the width is larger than the thickness of the bonding wire. The enlarged portion may be defined as a ball portion.
The lead terminals 211 to 214 have shapes that are line-symmetric with each other. Specifically, the lead terminal 213 has two sides m1 and m2 parallel to each other in a plan view, and one of the sides m1 overlaps the rectangular long side of the magnetic sensor 200 and the other side m2 Has one end on a short side of the rectangular shape, and extends from the inside to the inside of the rectangular shape. The other end of the side m2 is located substantially at the center between both ends of the side m1. The lead terminal 213 has a side m3 that extends obliquely from the other end of the side m2 and reaches the long side of the rectangular shape in plan view, and reaches the long side of the rectangular shape of the side m3. In the position shown, the side m3 and the side m1 intersect. The connection between the side m2 and the side m3 is drawn in a gentle curve.

Further, as shown in FIG. 2A, the side m3 of the lead terminal 213 is formed in a shape that is substantially orthogonal to an extension of a square diagonal having the contact portions 51 to 54 as vertices and near the center of the side m3. . The term “substantially orthogonal” as used herein refers to an angle that can be regarded as substantially orthogonal between an extension of the diagonal of the quadrangle and the side m3. For example, it is about 85 ° or more and 95 ° or less. Say.
On the other hand, of the two ends of the side m1, the end opposite to the side intersecting the side m3 extends halfway to the rectangular corner of the magnetic sensor 200. On the other hand, the lead terminal 213 has a side m4 extending from one end of the side m2 toward a long side overlapping the side m1 in a plan view.

The end of the side m4 opposite to the side connected to the side m2 extends halfway to the rectangular corner of the magnetic sensor 200, and the end of the side m4 on the corner side and the side m1 The connection with the end on the same corner side is connected via a curve m5 that is convex inside the lead terminal 213.
By connecting between the side m1 and the side m4 via the curve m5, a substantially fan-shaped region where the lead terminal 213 is not formed in a plan view is formed at the corner of the magnetic sensor 200. Therefore, the side surface forming the curve m5 of the lead terminal 213 in plan view is covered with the sealing member 230, that is, the corner of the magnetic sensor 200 is covered with the sealing member 230. As a result, the adhesion between the sealing member 230 and the lead terminal 213 is improved, and the mounting strength is improved.

  Since the lead terminals 211 to 214 have shapes that are line-symmetric to each other, the magnetic sensor 200 has a portion corresponding to the side m1 of each of the lead terminals 211 to 214 exposed on the side surface in the longitudinal direction, On the side surface in the lateral direction, portions corresponding to the sides m4 of the lead terminals 211 to 214 are exposed. In addition, the sealing members 230 exist at the four corners of the magnetic sensor 200. As a result, the mounting strength at the time of mounting on the substrate is improved, and the height of the element after mounting can be reduced because soldering can be performed using the side surfaces of the lead terminals.

As shown in FIG. 2A, the Hall element 100 is disposed substantially at the center of a region surrounded by the lead terminals 211 to 214. As shown in FIG. 2A, each side m3 of the lead terminal 211 to the lead terminal 214 is substantially orthogonal to a rectangular diagonal extension line having the contact portions 51 to 54 as vertices and near the center of the side m3. I do.
Here, the case where the lead terminals 211 to 214 have shapes that are line-symmetric with each other has been described, but the present invention is not limited to this.

  The four lead terminals 211 to 214 are, in plan view, a line segment connecting the contact portion connecting the electrode portion connected to one lead terminal to the magnetic sensing portion and the one lead terminal at the shortest distance. The angle formed by connecting a point on the contact portion of the line segment with a diagonal line passing through a point on the contact portion of the square is less than 30 degrees. Just do it. For example, as shown in FIG. 3A, in the case of the lead terminal 211, a contact portion that connects the electrode portion 31 connected to the lead terminal 211 to the magneto-sensitive portion 20, that is, connects the contact portion 51 and the lead terminal 211 at the shortest distance. The line segment is a line segment L1 shown in the figure. Similarly, in the case of the lead terminal 212, the line segment L2, in the case of the lead terminal 213, the line segment L3, and in the case of the lead terminal 214, the line segment L4 is a line segment connecting the shortest distance.

Then, the angle at which the diagonal line L6 of the rectangle L5 formed by connecting the points on the contact portions 51 to 54 corresponding to the line segments L1 to L4 intersects with the line segment L1, and the diagonal line L6 and the line segment L2 are formed. What is necessary is just to form so that the intersection angle is less than 30 degrees. Similarly, it is only necessary that the angle at which the diagonal line L7 of the rectangle L5 intersects with the line segment L3 and the angle at which the diagonal line L7 intersects with the line segment L4 are less than 30 degrees.
2A and 2B, the lead terminals 211 to 214 are electrically connected to the outside via the exterior plating layer 240. In the lead terminals 211 to 214, the outer plating layer 240 is formed on the surface opposite to the surface connected to the bonding wires 251 to 254. Thereby, the Hall element 100 is electrically connected to the outside of the magnetic sensor 200. In addition, the exterior plating layer 240 is formed of, for example, tin (Sn), but is not limited thereto.

The protective layer 220 covers the surface of the Hall element 100 opposite to the surface connected to the bonding wires 251 to 254. The protective layer 220 is not limited as long as the material can protect the substrate 10, for example. The protective layer 220 may be a film made of any one of a conductor, an insulator, and a semiconductor, or may be a film containing two or more of these. In the case of a conductor, the protective layer 220 may be a conductive resin such as a silver paste. In the case of an insulator, the protective layer 220 may be an insulating paste containing an epoxy-based thermosetting resin and silica (SiO ₂ ), silicon nitride, silicon dioxide, or the like. In the case of a semiconductor, the protective layer 220 may be a bonded substrate such as a Si substrate or a Ge substrate.

The sealing member 230 seals the Hall element 100, the bonding wires 251 to 254, and the lead terminals 211 to 214. The sealing member 230 is formed of a material that can withstand high heat during reflow. For example, the sealing member 230 is formed of an epoxy-based thermosetting resin. The outer shape of the sealing member 230 forms the outer shape of the magnetic sensor 200.
Here, in the Hall element 100, as shown in FIG. 1A, the areas of the input contact portions 51 and 52 are different from the areas of the output contact portions 53 and 54. Therefore, charge storage by the Hall effect can be performed efficiently, and as a result, a larger output voltage can be obtained.

If the area of the contact portions 51 to 54 is made larger or smaller, a larger output voltage can be obtained. On the other hand, current concentration increases near the contact portions 53 and 54 having a small area.
Furthermore, when the lead terminals 211 to 214 and the Hall element 100 are integrally sealed, stress in the vicinity of the lead terminals caused by the sealing is likely to be applied to a contact portion where current is concentrated, and the contact portions 53 and 54 having a small area. Is significantly affected by stress, and as a result, the variation in output voltage increases, making it difficult to improve the S / N ratio.

  In the magnetic sensor 200 according to the present embodiment, as shown in FIG. 3A, the four lead terminals 211 to 214 are, when viewed in a plan view, a contact for connecting an electrode part connected to one lead terminal to the magnetic sensing part. L1 of the diagonal lines L6 and L7 of the rectangle L5 formed by connecting the points on the contact portions of the line segments L1 to L4 and the line segments L1 to L4 at the shortest distance between the portion and one lead terminal. The angle at which the diagonal line L6 or L7 passing through a point on the contact portion of L4 to L4 intersects is less than 30 degrees. Therefore, the corners of the Hall element 100, that is, the contact portions 51 to 54 and the sides m3 of the lead terminals 211 to 214 face each other, and the contact portions 51 to 54 are apex. An extension line of the quadrangular diagonal line and each side m3 of the lead terminals 211 to 214 located on the extension line are substantially orthogonal to each other near the center of the side m3.

  Therefore, as shown by an arrow k1 in FIG. 3A, for example, the contact portion 53 reduces the influence of the stress generated in the lead terminal 213 from the direction of the side m3 which is closest to the contact portion 53 and substantially parallel to the diagonal line L7. It is expected that a change in output voltage due to the stress applied to the contact portion 53 due to the stress is reduced. Therefore, it is possible to reduce the variation in the output voltage due to the variation in the stress, and as a result, it is possible to improve the S / N ratio. As shown in FIG. 3B, the lead terminals 211 to 214 have a substantially rectangular shape, and have a shape extending to one short side and one long side of the magnetic sensor 200. Line segments L1 to L4 connecting the four lead terminals 211 to 214 and the corresponding contact portions 51 to 54 at the shortest distance, and contact portions 51 to 51 corresponding to these line segments L1 to L4, respectively. When the angle at which the corresponding diagonal line L6 or L7 of the rectangle L5 formed by connecting the points on the line 54 intersects with each other is 30 degrees or more, for example, the lead terminal 213a closest to the contact portion 53 The stress k2 generated at the corner m11 mainly acts. For this reason, stress acts on only one side of the Hall element 100 across the diagonal line passing through the contact portions 53 and 54, and there is a possibility that the output voltage varies due to the variation in the stress.

Further, in the magnetic sensor 200 according to the present embodiment, as shown in FIG. 2A, since the lead terminals 211 to 214 have a line-symmetric shape, the offset voltage caused by the different shapes of the lead terminals 211 to 214 is different. Can be suppressed, and the variation of the output voltage can be further suppressed.
In the above embodiment, the side m3 of the lead terminals 211 to 214 facing the Hall element 100 is a straight line in a plan view, but is not limited thereto, and may be, for example, a curved line.

  As described above, the embodiment of the present invention has been described. However, the above embodiment is an example of an apparatus and a method for embodying the technical idea of the present invention. It does not specify the material, shape, structure, arrangement, etc. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

DESCRIPTION OF SYMBOLS 10 Substrate 20 Magnetic sensing part 21 Conductive layer 22 Surface layer 31-34 Electrode part 40 Insulating film 51-54 Contact part 70 Electrode layer 100 Hall element 200 Magnetic sensor 211-214 Lead terminal 251-254 Bonding wire 230 Sealing member

Claims (5)

Element part,
Four lead terminals,
A magnetic sensor having a rectangular shape in plan view, comprising: a sealing member that seals the element portion and the lead terminal.
The element unit includes:
A substrate formed in a rectangular shape in plan view;
A magnetic sensing portion formed on the substrate,
An insulating film formed on the magneto-sensitive portion,
Four electrode portions formed on the insulating film and each connected to the lead terminal;
Four contact portions are provided at positions corresponding to the vertexes of a square in plan view corresponding to each of the electrode portions, and penetrate the insulating film to electrically connect the electrode portion and the magneto-sensitive portion, Has,
The area surrounded by the square is all included in the magneto-sensitive section in plan view,
Of the two sets formed by the two contact parts existing on the diagonal line of the quadrangle, each area in plan view of two contact parts included in one set is two contacts included in the other set. Larger than each area in plan view of the part,
The sides of the substrate are arranged so as to be parallel to the sides of the magnetic sensor in plan view, and the four lead terminals are arranged at four corners of the magnetic sensor, respectively.
For each of the four lead terminals,
A line connecting the contact portion connecting the electrode portion connected to the one lead terminal to the magnetic sensing portion and the shortest distance between the one lead terminal in plan view, and the contact portion of the line segment A magnetic sensor, wherein an angle at which a diagonal of a rectangular diagonal formed by connecting upper points and a diagonal passing through a point on the contact portion of the line intersects is less than 30 degrees.   The magnetic sensor according to claim 1, wherein two contact portions included in the other pair have the same shape.   The magnetic sensor according to claim 1, wherein the magnetic sensing unit is a square in plan view.   The two electrode portions connected to the two contact portions included in the one set are input electrode portions for applying an input signal, and the two electrode portions connected to the two contact portions included in the other set. 4. The magnetic sensor according to claim 1, wherein the electrode unit is an output electrode unit for detecting an output signal from the magnetic sensing unit. 5.   5. The four lead terminals according to claim 1, wherein the four lead terminals are line-symmetric with respect to at least one of straight lines passing through midpoints of opposing sides of the rectangular magnetic sensor in plan view. 6. A magnetic sensor according to claim 1.

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