JP2018088515A - Hall element and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a Hall element comprising contacts.SOLUTION: There is provided a Hall element comprising: a substrate; a magnetism sensitive part formed on the substrate and an insulating film formed on the magnetism sensitive part; electrode parts formed on the insulating film; and conductive parts extending from peripheral areas of the magnetism sensitive part toward a central area of the magnetism sensitive part, penetrating the insulating film, and being electrically connected to the magnetism sensitive part, where when being observed on a cross section passing through a center of the magnetism sensitive part and portions at which the conductive parts are in contact with the magnetism sensitive part in a plan view, at least parts of the conductive parts extend below the insulating film.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a Hall element and a method for manufacturing the Hall element.

Conventionally, a Hall element having a contact for connecting a magnetic sensitive part and an electrode pad is known (see, for example, Patent Documents 1 and 2).
Patent Document 1 Japanese Patent Laid-Open No. 60-175471 Patent Document 2 Japanese Patent Laid-Open No. 62-12974

  However, in the conventional Hall element, current concentrates at the lower end of the contact, and the Hall output voltage may vary.

  In the first aspect of the present invention, the substrate, the magnetic sensing portion formed on the substrate, the insulating film formed on the magnetic sensing portion, the insulating film formed on the insulating film, and sensing from the peripheral region of the magnetic sensing portion. The magnetic part includes a conductive part that extends toward the central region of the magnetic part, penetrates the insulating film, and is electrically connected to the magnetic sensitive part. The center of the magnetic sensitive part and the conductive part in plan view are in contact with the magnetic sensitive part. Provided is a Hall element in which at least a part of a conductive portion extends to a lower portion of an insulating film in a cross section when observed in a cross section passing through the portion.

  In the second aspect of the present invention, a step of providing a substrate, a step of forming a magnetic sensitive portion on the substrate, a step of forming an insulating film on the magnetic sensitive portion, and a magnetic sensitive portion from the peripheral region of the magnetic sensitive portion. And forming a conductive portion on the insulating film that extends to the central region side of the portion and penetrates the insulating film and is electrically connected to the magnetic sensitive portion. Provided is a Hall element manufacturing method in which at least a part of a conductive portion extends to a lower portion of an insulating film in a cross section when the portion is observed in a cross section passing through a portion in contact with a magnetic sensitive portion.

  The summary of the invention does not enumerate all the features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

An example of the top view of Hall element 100 concerning Example 1 is shown. An example of the AA 'cross section of Hall element 100 is shown. An example of the BB 'cross section of the Hall element 100 is shown. 3 is an example of a central region 23 of the Hall element 100 according to the first embodiment. 3 is a plan view illustrating an example of a configuration of an electrode unit 31 to an electrode unit 34. FIG. An example of the top view of Hall sensor 200 is shown. 2 is an example of a cross-sectional view of a hall sensor 200. FIG. The structure of the Hall element 500 which concerns on the comparative example 1 is shown. An example of a configuration of the Hall element 100 according to the second embodiment is shown. An example of a configuration of the Hall element 100 according to the third embodiment is shown. 10 is a schematic diagram for explaining a planar shape of a magnetic sensitive part 520 according to Comparative Example 2. FIG. 10 is a schematic diagram for explaining a planar shape of a magnetic sensitive part 520 according to Comparative Example 2. FIG. An example of the enlarged view of the magnetic sensing part 20 and the contact 50 is shown. An example of the enlarged view of the magnetic sensing part 20 and the contact 50 is shown. An example of the planar shape of the contact 50 is shown. An example of the planar shape of the contact 50 is shown. An example of the planar shape of the contact 50 is shown. An example of the planar shape of the contact 50 is shown. An example of a method for manufacturing the Hall element 100 will be described. An example of a method for manufacturing the Hall element 100 will be described. An example of a method for manufacturing the Hall element 100 will be described. An example of a method for manufacturing the Hall element 100 will be described. An example of a method for manufacturing the Hall element 100 will be described. An example of a method for manufacturing the Hall element 100 will be described. An example of the top view of Hall sensor 200 is shown. 2 is an example of a cross-sectional view of a hall sensor 200. FIG. An example of the enlarged view of Hall element 100 which has ball part 60 is shown. An example of an enlarged view of the Hall element 100 having the dummy ball 65 is shown. An example of the cross-sectional shape of the Hall element 100 is shown. An example of the cross-sectional shape of the Hall element 100 is shown. An example of the cross-sectional shape of the Hall element 100 is shown.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

[Example 1]
FIG. 1A illustrates an example of a plan view of the Hall element 100 according to the first embodiment. FIG. 1B shows an example of an AA ′ cross section of the Hall element 100. FIG. 1C shows an example of the BB ′ cross section of the Hall element 100. The Hall element 100 of this example includes a substrate 10, a magnetic sensitive part 20, an electrode part 31 to an electrode part 34, an insulating film 40 and a contact 50. The magnetic sensitive part 20 of this example includes a conductive layer 21 and a surface layer 22. Electrode part 31-electrode part 34 and contact 50 constitute a conductive part.

The substrate 10 is a semiconductor substrate such as Si or a compound semiconductor. The substrate 10 of this example is a GaAs substrate. In one example, the resistivity of the GaAs substrate is 1.0 × 10 ⁵ Ω · cm or more. The upper limit of the resistivity of the GaAs substrate 10 may be 1.0 × 10 ⁹ Ω · cm or less. The substrate 10 has a rectangular planar shape. In the present specification, the planar shape refers to a shape in plan view. The plan view means a top view.

  The magnetic sensitive part 20 is formed on the substrate 10. Further, the magnetic sensitive part 20 may be formed inside the substrate 10. In one example, the planar shape of the magnetic sensing unit 20 is a rectangle, a cross, or the like. The magnetic sensitive part 20 of this example has a rectangular planar shape. The magnetic sensitive part 20 is a layer having a lower resistance than the substrate 10. In one example, the magnetic sensitive part 20 is formed of a compound semiconductor such as GaAs, InSb, and InAs. The magnetic sensitive part 20 of this example is made of GaAs. Further, the magnetic sensitive unit 20 may be activated by injecting impurities such as Si, Sn, S, Se, Te, Ge, and C into the substrate 10 and heating them.

  Note that in the Hall element 100 of the present embodiment, it is preferable that all of the region surrounded by the four contacts 50 is included in the magnetic sensitive part 20. By making the entire region surrounded by the four contacts 50 into a shape that is included in the magnetic sensing unit 20, it is possible to make the shape less likely to cause current concentration. In addition, the area of the magnetic sensitive part 20 relative 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 contacts 50 is included in the magnetic sensing unit 20, the magnetic sensing unit 20 may extend outside the region surrounded by the four contacts 50. For example, the edge of the magnetic sensing part 20 may not be a straight line, and a notch or the like may be formed in the edge of the magnetic sensing part 20. Further, the region surrounded by the four contacts 50 can be determined as follows. First, the center of gravity of the magnetic sensing unit 20 is the center of the magnetic sensing unit 20 as viewed from above. Next, a point where the distance between the center of the magnetic sensing unit 20 and each contact 50 is minimum is drawn on each contact 50. A region formed by connecting these points is defined as a region surrounded by the four contacts 50. Note that when each contact has a plurality of points having the minimum distance from the center of the magnetic sensing unit 20, the region connecting all these points is defined as a region surrounded by the four contacts 50. Further, when the Hall element 100 includes a contact that is not used for either input or output, the above-described region may be determined without considering the contact.

  The magnetic sensitive part 20 of the present example has a planar shape in which at least one corner is rounded. In the present specification, the radius of curvature is not particularly limited as long as it is a shape with rounded corners. For example, the roundness means having a radius of curvature of 10% to 10000% with respect to the thickness of the magnetic sensitive part 20. Moreover, you may have two or more locations which have the said curvature radius in one corner. The current flowing through the Hall element 100 may concentrate at the end of the magnetic sensing unit 20. 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. Note that this effect becomes significant when the magnetically sensitive portion 20 is formed on the substrate 10 in a stepped shape (mesa shape). The magnetic sensitive part 20 of this example has a rectangular planar shape with four rounded corners. The center 25 refers to the center point of the planar shape of the magnetic sensing unit 20. By having a curvature radius of 10% or more with respect to the thickness of the magnetic sensing part 20, it is preferable in that current concentration at the end of the magnetic sensing part 20 can be relaxed. Moreover, it is preferable in that the fluctuation of the output voltage of the Hall element 100 can be suppressed by having a radius of curvature of 10000% or less with respect to the thickness of the magnetic sensitive part 20. This is because the exposure of the surface other than the smallest surface (for example, (100) surface) of the dangling bond can be reduced on the side surface of the magnetic sensitive portion 20, and the surface recombination of carriers is less likely to occur. From the above viewpoint, the radius of curvature is preferably a size [0] of 30 to 5000%, more preferably 50 to 1000%. Further, especially when the planar shape of the magnetic sensing unit 20 is rectangular, the amount of current flowing through the end of the magnetic sensing unit 20 increases, so that a current concentration alleviating effect is remarkably obtained.

  The conductive layer 21 is formed on the substrate 10. The conductive layer 21 in this example is n-type GaAs. The film thickness of the conductive layer 21 is not particularly limited. The film thickness of the conductive layer 21 in this example is 50 nm or more and 2000 nm or less. The film thickness of the conductive layer 21 may be 100 nm or more and 1000 nm or less.

  The surface layer 22 is formed on the conductive layer 21 with a conductive material. The surface layer 22 is made of a high-resistance crystal such as a GaAs layer having a lower conductivity than the conductive layer 21, AlGaAs or AlAs. The film thickness of the surface layer 22 in this example is 150 nm or more. Further, the film thickness of the surface layer 22 may be 200 nm or more. The upper limit of the film thickness of the surface layer 22 may be 800 nm or less or 600 nm or less. Note that the surface layer 22 may not be formed on the magnetic sensitive part 20.

The insulating film 40 is formed on the magnetic sensitive part 20. The insulating film 40 in this example is formed on the surface layer 22. The insulating film 40 is provided with a contact opening. In one example, the thickness of the insulating film 40 is 100 nm or more, but is not limited thereto. For example, the insulating film 40 includes 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 stacked. It is a membrane. For simplification, the insulating film 40 is omitted from the plan view.

  The electrode portions 31 to 34 are formed on the insulating film 40. In one example, the electrode portion 31 and the electrode portion 32 are input electrode portions for causing a current to flow through the magnetic sensitive portion 20. In this case, the electrode part 33 and the electrode part 34 are output electrode parts for detecting the Hall voltage of the magnetic sensing part 20. In this specification, the electrode unit 31 and the electrode unit 32 will be described as input electrode units, and the electrode unit 33 and the electrode unit 34 will be described as output electrode units. However, the input and output electrodes are interchanged. Also good. The Hall element 100 may have an electrode portion other than the above.

  FIG. 1D is an example of the central region 23 of the Hall element 100 according to the first embodiment. FIG. 1E is a plan view illustrating an example of a configuration of the electrode unit 31 to the electrode unit 34.

  The magnetic sensing unit 20 includes a central region 23 including the center 25 of the magnetic sensing unit 20 in a plan view, and a peripheral region 24 located around the central region 23. The central region 23 is a main region that contributes to the Hall effect, particularly in the magnetic sensitive portion 20. Further, the outside of the central region 23 is set as a peripheral region 24.

  In one example, the central region 23 has a perfect circular planar shape. The central region 23 in this example is shown as an inner region of a circle indicated by a broken line. The central region 23 is a circle having the same center as the center 25 of the magnetic sensing unit 20 in a plan view, and defines an auxiliary circle 30 having a minimum distance from the center of gravity of the magnetic sensing unit 20 to the contact 50 as a radius. The central region 23 is an inner region of a circle having a diameter of ½ with respect to the auxiliary circle 30 and centered on the center of gravity of the magnetically sensitive portion 20. Note that the geometric center of gravity of the magnetic sensing unit 20 can be calculated in a figure surrounded by the boundary between the magnetic sensing unit 20 and the substrate 10 in plan view. The central region 23 may have a rectangular planar shape. Here, each electrode part should just have the part extended to the said center area | region 23 side. That is, what is necessary is just to have the part extended to the center area | region 23 side of the magnetosensitive part 20 by planar view rather than the part which the outermost surface of the magnetosensitive part 20 and the electroconductive part (or contact 50) contact.

  The electrode part 31 and the electrode part 32 face each other in the first direction. In addition, the electrode part 33 and the electrode part 34 face each other in a second direction that intersects (for example, is orthogonal to) the first direction in plan view. The electrode portions 31 to 34 extend from the peripheral region 24 to the central region 23 of the magnetic sensitive unit 20.

  That is, the electrode part 31 includes a main part 31 a and an extending part 31 b extending from the main part 31 a to the central region 23 of the magnetic sensitive part 20. The electrode part 32 has a main part 32a and an extending part 32b extending from the main part 32a to the central region 23 of the magnetic sensitive part 20. The electrode part 33 includes a main part 33a and an extending part 33b extending from the main part 33a to the central region 23 of the magnetic sensitive part 20. The electrode part 34 includes a main part 34 a and an extending part 34 b extending from the main part 34 a to the central region 23 of the magnetic sensitive part 20.

  As shown in FIG. 1E, the distance between the electrode part 31 and the electrode part 32 in the first direction (that is, the distance between the extension parts 31b and 32b) is D1, and the electrode part 33 in the second direction When the distance from the electrode portion 34 (that is, the distance between the extended portions 33b and 34b) is D2, D1 and D2 are 1 μm or more and 40 μm or less, respectively.

  The electrode part 31, the electrode part 32, the electrode part 33, and the electrode part 34 have a rectangular planar shape. Further, the corner portion 31 c included in the electrode portion 31, the corner portion 32 c included in the electrode portion 32, the corner portion 33 c included in the electrode portion 33, and the corner portion 34 c included in the electrode portion 34 are located above the magnetic sensing portion 20. Each is located.

  Here, the corner part 31 c is a part included in the extension part 31 b of the electrode part 31. The corner part 32 c is a part included in the extension part 32 b of the electrode part 32. The corner part 33 c is a part included in the extension part 33 b of the electrode part 33. The corner part 34 c is a part included in the extension part 34 b of the electrode part 34. As shown in FIG. 1E, the corner portion 31c, the corner portion 32c, the corner portion 33c, and the corner portion 34c are arranged adjacent to each other. The corner portion 31c is adjacent to the corner portion 33c and the corner portion 34c, the corner portion 32c is adjacent to the corner portion 33c and the corner portion 34c, and the corner portion 31c and the corner portion 32c face each other in the first direction. The portion 33c and the corner portion 34c face each other in the second direction.

  In the plan view, the center position of the region surrounded by the corner portion 31c, the corner portion 32c, the corner portion 33c, and the corner portion 34c overlaps the center 25 of the magnetic sensing portion 20. Further, in plan view, the outer periphery of each of the electrode part 31, the electrode part 32, the electrode part 33, and the electrode part 34 is located inside a region surrounded by the outer periphery of the magnetic sensing part 20.

  The electrode part 31 to the electrode part 34 are respectively arranged at four rectangular corners of the substrate 10. In addition, each side of the electrode unit 31 to the electrode unit 34 is arranged to be parallel or perpendicular to the side of the substrate 10. When the electrode part 31-electrode part 34 is formed on the magnetic sensitive part 20, the magnetic sensitive part 20 can suppress the influence of chipping because at least one corner is rounded. Here, dicing is performed when the substrate 10 is singulated, but when there is no electrode part 31 to electrode part 34 between the outer peripheral part of the substrate 10 and the outer peripheral part of the magnetic sensitive part 20, the magnetic sensitive part 20 by chipping. Chipping, current concentration may occur due to the chipping. In particular, when the corner of the magnetic sensitive part 20 is not rounded, the stress from the insulating film 40 or the stress at the time of dicing may concentrate on the corner of the magnetic sensitive part and become a starting point of a crack. When at least one corner of the magnetic sensing portion 20 is rounded, current concentration can be alleviated by reducing the stress and the like and suppressing chipping of the end of the magnetic sensing portion 20 due to chipping. The electrode portions 31 to 34 of this example have the same planar shape but may have different planar shapes. For example, the input electrode portion and the output electrode portion may have different planar shapes. Further, the electrode portions 31 to 34 are electrically connected to the magnetic sensitive portion 20 through openings provided in the insulating film 40. The electrode part 31 to the electrode part 34 in this example are electrically connected to the magnetic sensitive part 20 via the contact 50. The electrode portions 31 to 34 are formed of a conductive material such as metal or polysilicon. The electrode part 31-electrode part 34 of this example contains gold as a main component.

  In this embodiment, the electrode part 31 to the electrode part 34 are formed on the magnetic sensing part 20 in a plan view, but at least a part of these electrode parts extends to a region outside the magnetic sensing part 20 in a plan view. It may be extended. In addition, when the electrode part 31-electrode part 34 is formed on the magnetic sensitive part 20 by planar view, it is preferable at the point which can make the fluctuation | variation of the output voltage of the Hall element 100 small. This is because stress due to the difference in thermal expansion coefficient between the magnetic sensing part 20 and the electrode parts 31 to 34 is less likely to be applied to the magnetic sensing part 20.

  The contact 50 is formed on the magnetic sensitive part 20. The contact 50 electrically connects the electrode part 31 to the electrode part 34 and the magnetic sensing part 20. The contact 50 penetrates the insulating film 40 and electrically connects the electrode part 31 to the electrode part 34 and the magnetic sensitive part 20. The contact 50 of this example is formed of the same material as the electrode part 31 to the electrode part 34, for example. The electrode part 31-electrode part 34 and the contact 50 may be simultaneously formed by the same process as a conductive part. However, the contact 50 may be formed of a material different from that of the electrode portions 31 to 34. The contact 50 includes a plurality of input contacts for inputting current to the magnetic sensing unit 20 and a plurality of output contacts for outputting Hall electromotive force according to the input current. The electrode part 31 and the electrode part 32 in this example are input contacts, and the electrode part 33 and the electrode part 34 are output contacts. However, the Hall element 100 may perform a spinning current operation by switching the input contact and the output contact. The Hall element 100 may have contacts other than those described above.

  The contact 50 has a planar shape corresponding to the planar shape of the magnetic sensing unit 20. The planar shape corresponding to the planar shape of the magnetic sensing unit 20 may be the same shape as the magnetic sensing unit 20. The planar shape of the contact 50 in this example has a roundness in at least a part of the outer region corresponding to the outer peripheral side of the magnetic sensing unit 20. Further, the planar shape of the contact 50 may be rounded in the inner region on the center 25 side of the magnetic sensing unit 20. Thereby, the current concentration at the end of the magnetic sensitive part 20 is alleviated. When the planar shape of the magnetic sensing unit 20 is rectangular or when the entire region surrounded by the four contacts 50 is included in the magnetic sensing unit 20, the amount of current flowing at the end of the contact 50 is particularly large. Therefore, the current concentration relaxation effect is remarkably obtained. The planar shape of the contact 50 is not limited to this example as long as current concentration at the end of the contact 50 can be reduced. In the present specification, the outer region refers to a region that is the outer periphery of the contact 50 and is opposed to the outer periphery of the magnetic sensing unit 20. On the other hand, the inner region refers to a region on the side of the center 25 of the magnetic sensing unit 20 other than the outer region.

  As described above, the Hall element 100 of the present example alleviates current concentration in the magnetic sensitive unit 20. This makes it difficult for minute resistance fluctuations due to current concentration in the magnetic sensing unit 20 to occur. Therefore, the Hall element 100 of the present example can suppress 1 / f noise caused by current concentration.

  FIG. 2A shows an example of a plan view of the hall sensor 200. FIG. 2B is an example of a cross-sectional view of the Hall sensor 200. The hall sensor 200 includes a hall element 100, a lead terminal 211 to a lead terminal 214, a protective layer 220, a molding member 230, an exterior plating layer 240, and a bonding wire 251 to a bonding wire 254. The configuration of the hall sensor 200 of this example is an example, and the present invention is not limited to this.

  The Hall element 100 is connected to the lead terminals 211 to 214 by bonding wires 251 to 254. The electrode part 31 of this example is electrically connected to the lead terminal 211 by a bonding wire 251. The electrode part 32 is electrically connected to the lead terminal 212 by a bonding wire 252. The electrode part 33 is electrically connected to the lead terminal 213 by a bonding wire 253. The electrode part 34 is electrically connected to the lead terminal 214 by a bonding wire 254.

  Bonding wire 251 to bonding wire 254 are formed of a conductive material. The bonding wires 251 to 254 of this example are gold wires, but are not limited thereto. Bonding wire 251 to bonding wire 254 are covered with mold member 230. As a result, the bonding wires 251 to 254 are fixed.

  The lead terminals 211 to 214 are electrically connected to the outside through the exterior plating layer 240. In the lead terminal 211 to the lead terminal 214, an exterior plating layer 240 is formed on the surface opposite to the surface connected to the bonding wire 251 to the bonding wire 254. Thereby, the Hall element 100 is electrically connected to the outside of the Hall sensor 200. In addition, although the exterior plating layer 240 of this example is formed with tin (Sn), it is not restricted to this.

The protective layer 220 covers the surface of the Hall element 100 opposite to the surface connected to the bonding wires 251 to 254. In one example, the protective layer 220 is not limited as long as the material can protect the substrate 10. 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 including 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 is an insulating paste containing 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 mold member 230 molds the Hall element 100, the bonding wires 251 to 254, and the lead terminals 211 to 214. The mold member 230 is formed of a material that can withstand high heat during reflow. For example, the mold member 230 is formed of an epoxy thermosetting resin.

  Here, in the hall sensor 200 having a reduced thickness, the thickness of the mold member 230 on the hall element 100 is thin, so that an electromagnetic wave including light incident on the magnetosensitive part 20 of the hall element 100 is locally applied to the magnetosensitive part 20. The typical conductivity may be varied by the photoelectric effect. In addition, this variation causes an offset voltage Vu in the Hall element 100.

  On the other hand, in this example, the electrode part 31 to the electrode part 34 extend from the peripheral area 24 of the magnetic sensitive part 20 to the central area 23 in a plan view, and a part of the central area 23 is part of the electrode parts 31 to 31. It is covered with the electrode part 34. For example, the electrode part 31 to the electrode part 34 are formed to extend from the four corners of the rectangular substrate 10 to the central region 23 of the magnetic sensitive part 20. And in the center area | region 23, the extension parts 31b-34b of the electrode part 31-electrode part 34 are each arrange | positioned closely, and the clearance gap between adjacent electrodes is narrow. Thereby, a part of the central region 23 of the magnetic sensitive part 20 is covered with the electrode parts 31 to 34.

  Here, the metal which is an electrode member absorbs electromagnetic waves including light very well. Therefore, the electrode part 31 to the electrode part 34 can shield the electromagnetic wave incident on the magnetic sensing part 20 of the Hall element 100 and suppress local conductivity fluctuations in the magnetic sensing part 20. This has the effect of suppressing fluctuations in the offset voltage Vu.

  In particular, when the ratio of the total area on the central region 23 of the electrode part 31 to the electrode part 34 to the area of the central region 23 of the magnetic sensitive part 20 in a plan view is 10% or more and less than 100%, the offset voltage Vu varies. The effect which suppresses is high. This ratio is preferably 20% or more and 99% or less, and more preferably 40% or more and 95% or less.

  Moreover, it is preferable that the ratio of the area of the effective region under the electrode part 31-the electrode part 34 with respect to the total area of the effective region of the magnetic sensing part 20 is 40% or more and 99% or less in planar view. In this specification, the area of the effective area is an area excluding the total area of the contact area where the magnetic sensitive part 20 and the electrode part 31 to the electrode part 34 are in contact with each other in plan view. Say.

[Comparative Example 1]
FIG. 3 shows a configuration of the Hall element 500 according to the first comparative example. The Hall element 500 of this example includes a substrate 510, a magnetic sensitive part 520, electrode parts 531 to 534, and contacts 550. The basic configuration is the same as that of the Hall element 100 according to the first embodiment. However, the magnetic sensitive part 520 and the contact 550 are different from the magnetic sensitive part 20 and the contact 50 according to the first embodiment in that the corners of the planar shape are not rounded. An insulating film is provided between the magnetic sensitive part 520 and the electrode parts 531 to 534, but is omitted in this example.

  The magnetic sensitive part 520 has a rectangular planar shape. Unlike the magnetic sensing unit 20, the magnetic sensing unit 520 does not have roundness at the corners of the rectangle. Therefore, current concentration occurs at the corners of the magnetic sensitive part 520. In particular, when the electrode part 531 and the electrode part 532 are input contacts, current concentration tends to occur particularly at the corners of the magnetic sensing part 520 connected to the electrode part 531 and the electrode part 532.

  Contact 550 has a triangular planar shape. Unlike the contact 50, the contact 550 does not have a round corner at the planar shape. Therefore, current concentration occurs at the corner of the contact 550. In particular, current concentration tends to occur at the corners of the contacts 550 connected to the electrode portions 531 and 532.

  Here, a current is input through the magnetic sensing unit 520 between the contact 550 of the input electrode unit 531 and the contact 550 of the electrode unit 532. However, a current that should flow between the electrode portion 531 and the electrode portion 532 may wrap around the outer periphery of the contact 550 of the electrode portion 533 for output and the magnetic sensing portion 520 on the outer periphery of the contact 550 of the electrode portion 534. . In particular, in the Hall element 500 of this example, the shortest distance between the outer periphery of the magnetic sensitive part 520 and the contact 550 is larger than that in the case of the first embodiment. That is, the amount of current flowing through the magnetic sensing part 520 on the outer periphery of the contact 550 is larger than that of the Hall element 100 according to the first embodiment. As described above, when the current flowing through the outer periphery of the electrode portion 533 and the electrode portion 534 which are output contacts increases, an error may occur with respect to the Hall electromotive force detected by the electrode portion 533 and the electrode portion 534. In addition, a negative sensitivity characteristic may be caused in the output of the Hall element 500.

  On the other hand, in Example 1, the magnetic sensing part 20 and the contact 50 are designed so that no current flows through the magnetic sensing part 20 on the outer periphery of the contact 50. In one example, the planar shapes of the contact 50 and the magnetic sensing part 20 are determined so that the shortest distance between the contact 50 and the outer periphery of the magnetic sensing part 20 is shortened. For example, the shortest distance between the contact 50 and the outer periphery of the magnetic sensing unit 20 is 0.5 μm or more and 20 μm or less [0]. By setting the distance between the contact 50 and the magnetic sensing part 20 to 0.5 μm or more, the influence of the characteristic variation due to the displacement of the contact 50 is suppressed. By setting the distance between the contact 50 and the magnetic sensing portion 20 to 20 μm or less, the Hall element 100 hardly exhibits negative sensitivity characteristics, and an error with respect to the Hall electromotive force can be reduced. In addition, from the viewpoint of ease of production, it is preferably 1 μm or more and 15 μm or less [0], and more preferably 3 μm or more and 10 μm or less. Further, the smaller the contact 50 is, the higher the current density is, and a larger amount of current flows through the magnetic sensing portion 20 on the outer periphery of the contact 50, so this effect becomes remarkable. For example, the area of each contact 50 is 0.1% or more and 20% or less with respect to the area of the magnetic sensing unit 20. The area ratio can be measured by observing the Hall element 100 with an optical microscope in a top view. By setting the area of the contact 50 to 1% or more with respect to the area of the magnetic sensing part 20, the influence of the characteristic variation due to the variation in the contact resistance of the contact 50 is suppressed. By setting the area of the contact 50 to 20% or less with respect to the area of the magnetic sensing portion 20, the Hall element 100 hardly exhibits a negative sensitivity characteristic, and an error with respect to the Hall electromotive force can be reduced. In addition, from the viewpoint of ease of production, it is preferably 0.3% or more and 15% or less [0], and more preferably 0.5% or more and 10% or less.

  The planar shape of the contact 50 may be different between the input contact and the output contact. The planar shape of the output contact 50 is configured to block the current around the outer periphery of the contact 50, but the planar shape of the input contact 50 may not be configured to block the current around the outer periphery of the contact 50. For example, the distance between the plurality of output contacts and the outer peripheral side of the magnetic sensing unit 20 may be arranged to be closer than the distance between the plurality of input contacts and the outer peripheral side of the magnetic sensing unit 20.

[Example 2]
FIG. 4 shows an example of the configuration of the Hall element 100 according to the second embodiment. The planar shape of the magnetic sensitive part 20 of this example is a cross shape. In the Hall element 100 of this example, the same reference numerals as those of the Hall element 100 according to the first embodiment function in the same manner as in the first embodiment. In this example, differences from Example 1 will be particularly described.

  The magnetic sensitive part 20 has a cross-shaped planar shape. At least one corner of the planar shape of the magnetic sensitive part 20 is rounded. Thereby, the current concentration at the end of the magnetic sensitive part 20 is alleviated. Moreover, in the magnetic sensitive part 20 of this example, it does not have a bulge in the direction which goes to the edge part from the center 25. FIG. For example, not having a bulge in the direction from the center 25 to the end means that the magnetic sensing portion 20 between the input contacts 50 does not have a structure bulging toward the output contact 50 side. Point to. It can also be said that there is no region where the width increases from the center 25 of the magnetic sensitive portion 20 to the distal end direction of the extending portion. Thereby, the sensitivity fall of Hall element 100 can be prevented. This is considered to be derived from the fact that current can be suppressed from flowing to the magnetic sensing part 20 on the outer periphery of the output contact 50.

[Example 3]
FIG. 5 shows an example of the configuration of the Hall element 100 according to the third embodiment. The magnetic sensitive part 20 of this example has a planar shape in which a cross and a rectangle are overlapped. The magnetic sensitive part 20 has a planar shape with rounded at least one corner. Further, the planar shape of the contact 50 has a roundness in an outer region corresponding to the outer peripheral side of the magnetic sensitive portion 20. The magnetic sensitive part 20 of this example does not have a bulge in the direction from the center 25 toward the end. As a result, the Hall element 100 according to the present example suppresses the current from flowing into the magnetic sensing portion 20 on the outer periphery of the output contact 50. Therefore, the Hall element 100 of this example can reduce output fluctuation.

[Comparative Example 2]
6A and 6B are schematic views for explaining a planar shape of the magnetic sensing unit 520 according to the comparative example 2. FIG. For the sake of brevity, the configuration other than the magnetic sensing unit 520 is omitted.

  The magnetic sensitive part 520 of this example is different from the magnetic sensitive part 20 in that it has a bulge. The magnetic sensitive part 520 of this example has a bulge in the direction from the center 525 of the magnetic sensitive part 520 to the tip 526 of the magnetic sensitive part 520. When the magnetic sensitive part 520 has a bulge, the outer peripheral length of the magnetic sensitive part 520 becomes long, and the exposed area of the side surface of the magnetic sensitive part 520 becomes large. Here, many surfaces other than the smallest surface (for example, (100) surface) of the dangling bond are exposed on the side surface of the magnetic sensitive portion 520, and the surface recombination of the carrier occurs frequently. Thereby, the output voltage of the Hall element 500 may fluctuate.

  7A and 7B show examples of enlarged views of the magnetic sensitive part 20 and the contacts 50. FIG. For simplicity, the electrode part 31 to the electrode part 34 and the insulating film 40 are omitted.

  In FIG. 7A, the magnetic sensitive part 20 and the contact 50 have planar shapes corresponding to each other. The planar shapes corresponding to each other indicate that the outer periphery of the magnetic sensing unit 20 and the contact 50 are close to each other so that current does not wrap around the outer periphery of the contact 50.

  The magnetic sensitive part 20 has a rectangular planar shape. However, the magnetic sensitive part 20 of this example has a structure that relaxes current concentration at the corners. A rounded rectangular region is formed at the corner of the magnetic sensitive part 20 of this example. In the present specification, a case where a structure for reducing current concentration is provided at the corners of the rectangle is also included as an example in which the corners of the magnetism-sensitive portion 20 are rounded. That is, a plurality of roundnesses may be provided at one corner of the rectangular portion of the magnetic sensing unit 20. In this example, one corner of the magnetic sensitive part 20 has two roundnesses.

  The contact 50 has a shape corresponding to the shape of the magnetic sensitive part 20. The planar shape of the contact 50 in this example is similar to the shape of the magnetic sensing part 20 in the outer region corresponding to the outer peripheral side of the magnetic sensing part 20. For example, the planar shape of the contact 50 is a rounded rectangle along a rectangular region provided at the corner of the magnetic sensing unit 20. As a result, the distance between the outer periphery of the magnetic sensing unit 20 and the contact 50 can be easily reduced. And the path | route of the electric current which goes around the outer periphery of the magnetic sensing part 20 can be interrupted | blocked. Further, by making the planar shapes of the magnetic sensitive part 20 and the contact 50 similar, the distances outside the magnetic sensitive part 20 and the contact 50 can be made uniform. Thereby, the current at the end of the magnetic sensitive part 20 becomes uniform, and the current concentration can be further relaxed.

  In FIG. 7B, the magnetic sensitive part 20 and the contact 50 have planar shapes corresponding to each other. The planar shape of the magnetic sensitive part 20 of this example is a rectangle, but a structure for reducing the concentration of current is provided at the end. Protruding regions are provided at the corners of the magnetic sensitive unit 20. The protruding region is rounded so as to alleviate current concentration. Further, since the planar shapes of the magnetic sensing part 20 and the outer region of the contact 50 are similar, the current path that goes around the outer periphery of the magnetic sensing part 20 can be blocked. In addition, although the contact 50 of this example has a corner | angular part in a planar-shaped inner side area | region, the corner | angular part of an inner side area | region may also have roundness.

  8A to 8D show an example of the planar shape of the contact 50. FIG. The magnetic sensitive part 20 of this example has a planar shape with rounded rectangular corners. For simplicity, the electrode part 31 to the electrode part 34 and the insulating film 40 are omitted.

  In FIG. 8A, the contact 50 has an L-shaped planar shape. The contact 50 is formed so that the L-shape is along the corner of the magnetic sensing unit 20. Further, the planar shape of the contact 50 has a roundness in the outer region corresponding to the corner of the magnetic sensitive part 20. In this example, the inner region of the contact 50 is also formed to be rounded.

  In FIG. 8B, the contact 50 has a T-shaped planar shape. The contact 50 is formed such that the protruding portion of the T-shape faces the corner of the magnetic sensitive part 20. Further, the protruding portion of the T-shape has a roundness along the corner of the magnetic sensitive part 20. The planar shapes of the magnetic sensitive part 20 and the contact 50 in this example are not similar. However, the magnetic sensitive part 20 may have a planar shape similar to the contact 50 in the outer region.

  In FIG. 8C, the contact 50 has a rectangular planar shape. The contact 50 is formed such that a rectangular corner portion faces the corner portion of the magnetic sensitive portion 20. Further, the corners of the contact 50 are rounded along the corners of the magnetic sensitive part 20. The contact 50 of this example has a planar shape similar to the magnetic sensing part 20 in the outer region.

  In FIG. 8D, the contact 50 has a triangular planar shape. The contact 50 is formed so that the corners of the triangle face the corners of the magnetic sensing unit 20. In addition, the corners of the triangle are rounded along the corners of the magnetic sensitive part 20. The contact 50 in this example has a planar shape in which a triangle and a circle are overlapped. The planar shapes of the magnetic sensitive part 20 and the contact 50 in this example are not similar. However, the magnetic sensitive part 20 may have a planar shape similar to the contact 50 in the outer region.

  9A to 9F show an example of a method for manufacturing the Hall element 100. The manufacturing method of the Hall element 100 of this example is an example and is not limited thereto.

  In FIG. 9A, a substrate 10 is provided. The planar shape of the substrate 10 of this example is a rectangle. In FIG. 9B, the magnetic sensitive part 20 is formed on the substrate 10. In this example, the conductive layer 21 is formed on the substrate 10, and the surface layer 22 is formed on the conductive layer 21. In the film formation stage of the magnetic sensitive part 20, the planar shape of the conductive layer 21 and the surface layer 22 may be the same as the planar shape of the substrate 10. For example, the magnetosensitive portion 20 is formed by epitaxially growing a compound semiconductor on the substrate 10 using MOCVD (Metal Organic Chemical Deposition) or MBE (Molecular Beam Epitaxy) method.

  In FIG. 9C, the magnetic sensitive part 20 is etched into a predetermined planar pattern. Thereby, the planar shape of the magnetic sensitive part 20 is formed in a rectangle or a cross. Moreover, the corner | angular part of the planar shape of the magnetic sensitive part 20 may be rounded by the said etching process. In FIG. 9D, the contact 50 is formed on the magnetic sensitive part 20. The contact 50 is formed using any semiconductor manufacturing process such as vapor deposition or sputtering.

  In FIG. 9E, the insulating film 40 is formed on the substrate 10, the magnetic sensitive part 20, and the contact 50. In one example, a SiN film having a thickness of 300 nm is formed as the insulating film 40. The insulating film 40 is formed with an opening for electrically connecting the contact 50 and the electrode portions 31 to 34. The opening may be formed by an etching process. In FIG. 9F, electrode portions 31 to 34 are formed on the insulating film 40. In addition, the electrode portions 31 to 34 are electrically connected to the contacts 50 through openings formed in the insulating film 40. In an example, although the thickness of the electrode part 31-electrode part 34 is 0.5 micrometer, it is not restricted to this. Moreover, the electrode part 31-electrode part 34 may be connected with an external electrode by the bonding wire 251-bonding wire 254. FIG. A ball portion such as a gold ball may be provided on the electrode portion 31 to the electrode portion 34.

  In the manufacturing method of the Hall element 100 of this example, the step of forming the contact 50 is performed before the step of forming the insulating film 40. However, the step of forming the contact 50 may be performed after the step of forming the insulating film 40.

[Example 3]
10A and 10B illustrate an example of the configuration of the Hall element 100 according to the third embodiment. The Hall element 100 of this example further includes a ball portion 60.

  The ball part 60 is provided between each of the electrode part 31 to the electrode part 34 and the bonding wire 251 to the bonding wire 254. The ball part 60 is formed of a conductive material. Ball portion 60 may be formed of the same material as bonding wire 251 to bonding wire 254. The ball part 60 in this example is a gold ball. In one example, the ball part 60 has a diameter of 10 μm or more and 100 μm or less in plan view. When the ball part is not a perfect circle when viewed from above, it approximates an ellipse having the same area as the ball part when viewed from above, and the major axis of the ellipse is the diameter. The ball part 60 of this example has a diameter of 60 μm. Moreover, it is preferable that the thickness of the ball | bowl part 60 is 5 micrometers or more. The thickness of the ball part 60 is a distance between the highest part of the ball part 60 and the electrode part 31 to the electrode part 34 where the ball part 60 is disposed.

  Here, when the cross-sectional transmission diagram obtained by X-ray imaging of the Hall sensor 200 is observed, 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 part may be defined as the ball part 60.

  In plan view, the projected area of the ball part 60 occupies 10% or more of the projected area of the magnetic sensitive part 20. In one example, the projected area of the ball part 60 may be 15% or more, 20% or more, or 30% or more of the projected area of the magnetic sensitive part 20. Here, the projected area of the ball part 60 indicates the sum of the projected areas of all the ball parts 60 existing on the magnetic sensitive part 20. The ball part 60 blocks light incident on the magnetic sensitive part 20 by absorbing or reflecting light. Thereby, the local conductivity fluctuation | variation which arises when light injects into the magnetosensitive part 20 can be suppressed. In particular, when the Hall element 100 is thinned, local fluctuations in conductivity are likely to occur due to the photoelectric effect in the magnetosensitive portion 20. Therefore, the fluctuation of the offset voltage is suppressed. Thus, from the viewpoint of blocking light, it is preferable to increase the ratio of the projected area of the ball part 60 to the projected area of the magnetically sensitive part 20. Further, the ball portion is preferably provided on all of the electrode portions 31 to 34 of the Hall element 100. Further, at least one of the ball parts 60 is not sensitive to the electrode part 32 when observed in a cross section passing through the center 25 of the magnetic sensing part 20 and the center of the part where the electrode part 32 is in contact with the magnetic sensing part 20 in plan view. It is preferable to be provided on the side of the center 25 of the magnetic sensitive part 20 rather than the center of the part in contact with the magnetic part 20. Further, the ball portion 60 may be provided between the plurality of input contacts in a plan view. When the material of the ball part 60 is gold, the gold reflects light having a wavelength longer than the wavelength in the infrared region, so that the light having the wavelength in the infrared region can be prevented from entering the magnetic sensing unit 20. The material of the ball part 60 is not particularly limited to this example as long as it absorbs or reflects a predetermined wavelength so as to prevent light from entering the magnetic sensitive part 20. In addition, a thicker ball portion 60 is preferable from the viewpoint of blocking light, and is, for example, 5 μm or more and 100 μm or less. In addition, from the viewpoint of ease of production, it is preferably 10 μm or more and 80 μm or less, and more preferably 20 μm or more and 60 m or less.

  FIG. 11 shows an example of an enlarged view of the Hall element 100 having the ball portion 60. This figure shows a sectional view of the Hall element 100. The cross-sectional view of this example shows a cross section including the center 25 of the magnetic sensing part 20 and the center of the region where the electrode part 32 is in contact with the magnetic sensing part 20. In this embodiment, the magnetic sensitive part 20, the insulating film 40, the electrode parts 31 to 34, and the ball part 60 are formed, but other layers are provided between the layers or on each layer. Also good.

  The ball part 60 is provided between the bonding wire and the electrode part. The ball portion 60 of this example is provided between the bonding wire 252 and the electrode portion 32, but is also provided between other bonding wires and the electrode portion. The ball part 60 of this example is electrically connected to the electrode part 31 to the electrode part 34 and is provided on the magnetic sensitive part 20 in a plan view.

  The bonding wires 251 to 254 are electrically connected to the ball part 60 and are extended vertically from the electrode parts 31 to 34. By extending the bonding wires 251 to 254 vertically from the electrode portions 31 to 34, a magnetic field in a direction parallel to the magnetic sensitive portion 20 is less likely to be generated. Thereby, the fluctuation | variation of the output of Hall element 100 is suppressed and magnetic sensitivity improves. In one example, the bonding wire 251 to the bonding wire 254 are extended vertically from the electrode part 31 to the electrode part 34 by 5% or more of the diameter of the ball part 60. If the bonding wire 251 to the bonding wire 254 are vertically extended from the electrode part 31 to the electrode part 34 at a predetermined distance or more, then the bonding wire 251 to the bonding wire 254 are extended toward the lead terminal 211 to the lead terminal 214. May be.

  Further, the ball portion 60 may be formed on the contact 50. By forming the ball part 60 on the contact 50, the component of the current flowing in the direction parallel to the magnetic sensitive part 20 is reduced, and the magnetic sensitivity of the Hall element 100 is improved. The ball part 60 being formed on the contact 50 does not have to be formed entirely on the contact 50, and includes a case where at least a part of the ball part 60 is formed on the contact 50. It may be.

  Note that the bonding wires 251 to 254 do not have to be completely perpendicular to the electrode portions 31 to 34, and a magnetic field is generated for the magnetic sensing portion 20 and does not affect the magnetic sensitivity of the Hall element 100. It may be inclined to the extent. For example, the bonding wires 251 to 254 may have an inclination of 5 degrees or less from the direction perpendicular to the electrode portions 31 to 34. Further, the inclination from the direction perpendicular to the electrode part 31 to the electrode part 34 may be within 10 degrees, within 15 degrees, or within 20 degrees. By forming the bonding wire perpendicularly, the magnetic field caused by the current flowing through the bonding wire can be made parallel to the magnetic sensing unit 20. Thereby, the influence of the magnetic field on the magnetic sensing unit 20 can be reduced, and the error of the output voltage can be reduced. Note that the above effect is enhanced when the magnetic sensitive part 20 has a rectangular planar shape or when the entire area surrounded by the four contacts 50 is included in the magnetic sensitive part 20.

  The region P is a region near the boundary between the contact 50 and the magnetic sensing unit 20. The region P includes the interface between the contact 50 and the magnetic sensitive part 20. The contact 50 of this example has a structure for relaxing current concentration in the region P. When the contact 50 is observed in a cross section passing through the center 25 of the magnetic sensing portion 20 in plan view and the center of the portion where the electrode portion 32 is in contact with the magnetic sensing portion 20, at least a part of the contact 50 is insulated in the cross section. It extends to the lower part of the film 40. For example, at least a part of the side surface of the contact 50 is located on the side surface of the contact 50 that is closer to the center 25 side than the point where the side surface of the contact 50 is in contact with the outermost surface of the magnetic sensor portion 20. It is formed on the side opposite to the center 25 side. Further, the point where the side surface of the contact 50 and the outermost surface of the magnetic sensing part 20 are in contact with each other may extend toward the center 25 side of the magnetic sensing part 20. That is, the side surface of the contact 50 on the ball part 60 side may have a forward tapered cross-sectional shape, or the upper end may extend to the ball part 60 side. As a result, the contact 50 relaxes the current concentration at the point where the side surface of the contact 50 on the center 25 side and the outermost surface of the magnetosensitive portion 20 are in contact. Therefore, the heat generation at the point where the side surface of the contact 50 on the center 25 side and the outermost surface of the magnetic sensing portion 20 are in contact is suppressed, and the characteristic variation of the Hall element 100 is suppressed. Further, since current concentration near the contact 50 is suppressed, the electrode near the contact 50 is unlikely to peel off. Therefore, the reliability of the Hall element 100 is improved. The current concentration at the lower end of the contact 50 is a problem peculiar to the Hall element having the electrode portions 31 to 34 as in this embodiment. Thus, the shape of the upper end of the side surface on the center 25 side of the contact 50 is not particularly limited.

  At least one of the ball portions 60 is provided closer to the center 25 of the magnetic sensing portion 20 than the center of the portion where the electrode portion 32 is in contact with the magnetic sensing portion 20 when observed in the cross section. Further, the ball portion 60 may be provided between the plurality of input contacts in a plan view. In this case, a current path is formed such that the current flowing between the ball part 60 and the magnetic sensitive part 20 is turned back in the region P. And current concentration tends to occur in the region P. Therefore, the effect of making the contact 50 into a forward tapered shape is further enhanced.

  As described above, the Hall element 100 of the present example is connected perpendicularly to the bonding wires 251 to 254, so that the influence of the magnetic field on the magnetic sensing part 20 due to the current flowing through the bonding wires is reduced. The Hall element 100 has a structure that suppresses current concentration in the vicinity of the point where the side surface on the center 25 side of the contact 50 and the outermost surface of the magnetosensitive portion 20 are in contact with each other. Thereby, characteristic variation of the Hall element 100 is reduced.

  FIG. 12 shows an example of an enlarged view of the Hall element 100 having the dummy balls 65. This figure shows a sectional view of the Hall element 100. The cross-sectional view of this example shows a cross section including the center 25 of the magnetic sensing part 20 and the center of the region where the electrode part 32 is in contact with the magnetic sensing part 20. The Hall element 100 of this example further includes a dummy ball 65.

  The dummy balls 65 are provided on the electrode portions 31 to 34. The dummy ball 65 is a dummy ball portion that is not connected to the bonding wire. By providing the dummy ball 65, the light incident on the magnetic sensitive portion 20 can be blocked as in the case where the ball portion 60 is provided. In particular, it is preferable to provide the dummy ball 65 when the magnetically sensitive part 20 cannot be covered only by the ball part 60 connected to the bonding wires 251 to 254.

  FIG. 13 shows an example of a cross-sectional shape of the Hall element 100. The cross-sectional view of this example shows a cross section including the center 25 of the magnetic sensing part 20 and the center of the region where the electrode part 32 is in contact with the magnetic sensing part 20. The Hall element 100 of this example includes a conductive portion 80.

  The conductive part 80 includes an electrode part 32, a contact 50 and a contact 70. At least a part of the conductive portion 80 extends below the insulating film 40 in a cross section including the center 25 of the magnetic sensitive portion 20 and the center of the region where the electrode portion 32 is in contact with the magnetic sensitive portion 20. In this example, the contact 50 and the contact 70 extend below the insulating film 40 in the cross section.

  The contact 70 is formed at the interface between the contact 50 and the magnetic sensitive part 20 by annealing. The contact 70 is an alloy part formed by annealing. The contact 70 is formed on the magnetic sensitive part 20 below the contact 50. The contact 70 of this example extends from the contact 50 to the center 25 side of the magnetic sensitive unit 20 in plan view. In the Hall element 100 of this example, since the contact 50 and the contact 70 extend below the insulating film 40, the Hall element 100 near the point where the side surface on the center 25 side of the contact 50 and the outermost surface of the magnetically sensitive portion 20 are in contact with each other. Current concentration can be suppressed. In addition, since the current flows as the contact 50 is smaller, this effect becomes remarkable. For example, the area of the contact 50 is 0.1% or more and 20% or less with respect to the area of the magnetic sensitive part 20. By setting the area of the contact 50 to 0.1% or more with respect to the area of the magnetic sensing part 20, the influence of the characteristic variation due to the variation in the contact resistance of the contact 50 is suppressed. When the area of the contact 50 is 20% or less with respect to the area of the magnetic sensing part 20, current concentration in the vicinity of the point where the side surface on the center 25 side of the contact 50 contacts the outermost surface of the magnetic sensing part 20 can be suppressed. In addition, from the viewpoint of ease of production, it is preferably 0.3% or more and 15% or less [0], and more preferably 0.5% or more and 10% or less.

  φ1 represents an angle formed between the side surface of the contact 50 on the center 25 side and the outermost surface of the magnetic sensitive portion 20. φ1 is preferably an obtuse angle. As a result, the current concentration at the point where the side surface of the contact 50 on the center 25 side and the outermost surface of the magnetic sensitive portion 20 are in contact is further relaxed. From the viewpoint of alleviating the current concentration at the point where the side surface of the contact 50 on the center 25 side and the outermost surface of the magnetosensitive portion 20 are in contact, it is preferable that φ1 is large. In one example, φ1 is greater than 90 ° and less than 135 °.

  At least a part of the conductive portion 80 of this example extends 50 nm or more from the point where the side surface of the contact 50 and the outermost surface of the magnetic sensitive portion 20 are in contact to the center or the depth side of the magnetic sensitive portion 20. The region extending to the ball part 60 side of the conductive part 80 may be 100 nm or more, 150 nm or more, 200 nm or more, 1 μm or more. By extending to the depth side of the magnetic sensitive part 20, current concentration can be relaxed, and reliability fluctuations due to heat generation can be suppressed. The region extending to the ball portion 60 side of the conductive portion 80 can be formed in a predetermined shape by forming the contact 50 first. Even when the contact 50 is formed after the insulating film 40 is formed, at least a part of the conductive portion 80 can be diffused to the ball portion 60 side by performing an annealing process. As described above, the region where the conductive portion 80 extends toward the ball portion 60 may be adjusted to a predetermined size by etching or annealing of the conductive portion 80.

  The point where the side surface on the center 25 side of the contact 50 in this example and the outermost surface of the magnetic sensing portion 20 are in contact with each other is provided closer to the center 25 side of the magnetic sensing portion 20 than the upper end of the contact 50 in plan view. The contact 50 extends 100 nm or more toward the center or depth side of the magnetic sensing part 20 from the point where the side surface of the contact 50 and the outermost surface of the magnetic sensing part 20 are in contact with the center 25 side of the magnetic sensing part 20. Further, at least a part of the conductive portion 80 is formed on the insulating film 40 at the center side or the depth side of the magnetic sensitive portion 20 from the point where the side surface on the center 25 side of the conductive portion 80 contacts the outermost surface of the magnetic sensitive portion 20. You may extend 1/4 or more of thickness.

  In the manufacturing method of the Hall element 100 of this example, the insulating film 40 is formed on the contact 50 after the contact 50 is formed. In addition, after the opening is formed in the insulating film 40, the electrode portion 32 is formed on the insulating film 40 so as to be electrically connected to the contact 50. By forming the contact 50 first, the contact 50 can be formed to have a predetermined φ1.

  FIG. 14 shows an example of a cross-sectional shape of the Hall element 100. The cross-sectional view of this example shows a cross section including the center 25 of the magnetic sensing part 20 and the center of the region where the electrode part 32 is in contact with the magnetic sensing part 20. The Hall element 100 of this example includes a conductive portion 80.

  The conductive part 80 includes an electrode part 32, a contact 50 and a contact 70. At least a part of the conductive portion 80 extends below the insulating film 40 in a cross section including the center 25 of the magnetic sensitive portion 20 and the center of the region where the electrode portion 32 is in contact with the magnetic sensitive portion 20. In this example, the contact 50 and the contact 70 extend below the insulating film 40 in the cross section.

  The side surface on the center 25 side of the contact 50 in this example has a structure separated from the outermost surface of the magnetic sensing unit 20. As a result, the contact 70 is not formed at the interface between the side surface of the contact 50 on the center 25 side and the magnetic sensitive portion 20. Therefore, the contact 70 of this example is arranged so that the contact 50 extends to the center 25 side of the magnetic sensing unit 20 from the contact 70 in plan view. In the Hall element 100 of the present example, since the contact 50 and the contact 70 extend below the insulating film 40, the current concentration in the vicinity of the point where the side surface on the center 25 side of the contact 50 and the outermost surface of the magnetosensitive portion 20 are in contact with each other. Can be suppressed.

  FIG. 15 shows an example of a cross-sectional shape of the Hall element 100. The cross-sectional view of this example shows a cross section including the center 25 of the magnetic sensing part 20 and the center of the region where the electrode part 32 is in contact with the magnetic sensing part 20. The Hall element 100 of this example includes a conductive portion 80.

  The conductive portion 80 includes a contact 50 and a contact 70. The conductive portion 80 also serves as the electrode portion 31 to the electrode portion 34. That is, the conductive part 80 includes the electrode part 31 to the electrode part 34, the contact 50, and the contact 70. The contact 50 in this example is formed on the upper surface of the insulating film 40. However, at least a part of the contact 70 extends below the insulating film 40. Thereby, the Hall element 100 of this example can suppress the current concentration near the point where the side surface on the center 25 side of the contact 50 and the outermost surface of the magnetic sensing portion 20 are in contact with each other.

  The Hall element 100 of this example is different from the Hall element 100 according to FIG. In the manufacturing method of the Hall element 100 of this example, the insulating film 40 is formed on the magnetic sensitive part 20, and an opening for connecting the magnetic sensitive part 20 and the conductive part 80 is formed in the insulating film 40. Thereafter, the conductive portion 80 is formed on the insulating film 40. In this example, it is not necessary to form the electrode part 31 to the electrode part 34 and the contact 50 separately, and the conductive part 80 is formed at a time, so the manufacturing process can be reduced. Similarly, when the conductive portion 80 is provided, the contact 70 is formed between the magnetic sensitive portion 20 and the conductive portion 80 by annealing the conductive portion 80. In addition, by performing elemental analysis such as SEM-EDX or TEM-EDX on the cross section of the Hall element 100, a portion where the electrode material of the conductive portion 80 is detected is determined as a contact.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

DESCRIPTION OF SYMBOLS 10 ... Board | substrate, 20 ... Magnetosensitive part, 21 ... Conductive layer, 22 ... Surface layer, 23 ... Center area | region, 24 ... Peripheral area | region, 25 ... Center, 26. .. tip, 30 ... auxiliary circle, 31 ... electrode part, 31a ... main part, 31b ... extension part, 31c ... corner part, 32 ... electrode part, 32a ... -Main part, 32b ... Extension part, 32c ... Corner part, 33 ... Electrode part, 33a ... Main part, 33b ... Extension part, 33c ... Corner part, 34 ..Electrode part 34a ... main part 34b ... extension part 34c ... corner part 40 ... insulating film 50 ... contact 60 ... ball part 65 ...・ Dummy ball, 70 ... Contact, 80 ... Conducting part, 100 ... Hall element, 200 ... Hall sensor, 211 ... Lead terminal, 212 ... ,..., Lead terminal, 214... Lead terminal, 220... Protective layer, 230... Molding member, 240 .. exterior plating layer, 251. -Bonding wire, 253 ... Bonding wire, 254 ... Bonding wire, 500 ... Hall element, 510 ... Substrate, 520 ... Magnetosensitive part, 525 ... Center, 526 ... Tip 531 ... Electrode part, 532 ... Electrode part, 533 ... Electrode part, 534 ... Electrode part, 550 ... Contact

Claims (10)

A substrate,
A magnetic sensitive part formed on the substrate; an insulating film formed on the magnetic sensitive part;
A conductive portion formed on the insulating film, extending from a peripheral region of the magnetic sensitive portion to a central region side of the magnetic sensitive portion, and penetrating the insulating film and electrically connected to the magnetic sensitive portion; With
When observed in a cross section passing through the center of the magnetic sensing part in plan view and a part where the conductive part is in contact with the magnetic sensitive part, at least a part of the conductive part extends to the lower part of the insulating film in the cross section. Out Hall element. At least a part of the conductive portion extends 50 nm or more toward the center side or the depth side of the magnetic sensing portion from the point where the side surface of the conductive portion and the outermost surface of the magnetic sensing portion are in contact with each other in the cross section. Item 2. The Hall element according to Item 1. At least a part of the conductive part has a thickness of 1 of the insulating film on the center side or the depth side of the magnetic sensitive part from the point where the side surface of the conductive part and the outermost surface of the magnetic sensitive part contact each other in the cross section. The Hall element according to claim 1, wherein the Hall element is extended by / 4 or more. The conductive part is
An electrode portion extending from a peripheral region of the magnetic sensitive portion to a central region of the magnetic sensitive portion;
4. The Hall element according to claim 1, further comprising: a contact penetrating the insulating film and electrically connecting the electrode portion and the magnetically sensitive portion. 5. The Hall element according to claim 4, wherein the contact has a forward tapered cross-sectional shape. A ball portion electrically connected to the conductive portion;
6. The device according to claim 1, wherein at least one of the ball portions is provided closer to a center side of the magnetic sensing portion than a center of a portion where the conductive portion is in contact with the magnetic sensing portion in the cross section. Hall element. Providing a substrate;
Forming a magnetic sensitive part on the substrate;
Forming an insulating film on the magnetic sensitive portion;
Forming a conductive portion on the insulating film that extends from a peripheral region of the magnetic sensitive portion to a central region of the magnetic sensitive portion, penetrates the insulating film, and is electrically connected to the magnetic sensitive portion. And
When observed in a cross section passing through the center of the magnetic sensing part in plan view and a part where the conductive part is in contact with the magnetic sensitive part, at least a part of the conductive part extends to the lower part of the insulating film in the cross section. The manufacturing method of the hall element which has taken out. Forming the conductive portion comprises:
Forming an electrode portion on the insulating film;
Forming a contact penetrating the insulating film and electrically connecting the electrode part and the magnetic sensing part;
The method for manufacturing the Hall element according to claim 7, further comprising a step of electrically connecting to the electrode portion and forming a ball portion on the magnetically sensitive portion in plan view. The method of manufacturing a Hall element according to claim 8, wherein the step of forming the contact is performed before the step of forming the insulating film. The method further comprises the step of extending the contact toward the center of the magnetic sensing part from the point where the side surface of the conductive part and the outermost surface of the magnetic sensing part are in contact by alloying the contact by annealing. Item 10. A method for manufacturing a Hall element according to Item 8 or 9.

Images