Vertical hall element

Abstract

To provide a vertical hall element in which the spread of a current path of a sense current flowing through a semiconductor region is suppressed.SOLUTION: A vertical hall element 1 comprises: a conductive first semiconductor layer 20 which includes a first surface 210, and a second surface 220 directed opposite to the first surface 210, and in which a first region 211 is selectively set in a part of the first surface 210; a mask layer 80 which is arranged in a second region 212 excluding the first region 211 of the first surface 210, and which is an insulating layer or a conductive semiconductor having a different conductivity type from that of the first semiconductor layer; and a first magnetosensitive layer 301 which is arranged in the first region 211 of the first semiconductor layer 20, and which has a mesa shape with its bottom surface facing the first surface 210 and which is a conductive semiconductor of the same conductivity type as that of the first semiconductor layer 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vertical Hall element. [Background technology]

[0002] Vertical Hall elements that detect magnetic fields passing parallel to the substrate are used as Hall elements that utilize the Hall effect. In vertical Hall elements, the sensing current for detecting the magnetic field flows through the semiconductor region perpendicular to the substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-16863

[0004] [overview] The sensitivity of a vertical Hall element decreases when the current path of a sensing current flowing through a semiconductor region widens. An object of the present disclosure is to provide a vertical Hall element in which the current path of a sensing current flowing through a semiconductor region is suppressed from widening.

[0005] One aspect of the present disclosure is a vertical Hall element comprising: a conductive first semiconductor layer having a first surface and a second surface facing in the opposite direction to the first surface, with a first region selectively set in a portion of the first surface; an insulating layer or a mask layer made of a conductive semiconductor having a conductivity type different from that of the first semiconductor layer, disposed in the second region of the first surface excluding the first region; and a first magneto-sensitive layer, which is mesa-shaped with its bottom surface facing the first surface and made of a conductive semiconductor of the same conductivity type as the first semiconductor layer, disposed in the first region of the first semiconductor layer.

[0006] Another aspect of the present disclosure is a method for manufacturing a vertical Hall element, including: preparing a conductive first semiconductor layer having a first surface and a second surface facing in the opposite direction to the first surface, with a first region selectively set in a part of the first surface; selectively forming an insulating layer or a mask layer made of a conductive semiconductor having a conductivity type different from that of the first semiconductor layer in the second region of the first surface excluding the first region; and forming a first magneto-sensitive layer in the first region of the first semiconductor layer, the first magneto-sensitive layer having a mesa shape with a bottom surface facing the first surface and made of a conductive semiconductor of the same conductivity type as the first semiconductor layer. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic cross-sectional view showing the structure of a vertical Hall element according to the first embodiment. [Figure 2] FIG. 2 is a schematic perspective view for explaining the operation of the vertical Hall element according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram for explaining prevention of erroneous detection of a magnetic field by the vertical Hall element according to the first embodiment. [Figure 4] FIG. 4 is a schematic perspective view showing the structure of the magnetosensitive layer model. [Figure 5] FIG. 5 is a schematic cross-sectional view for explaining the expansion of the current path of the sensing current in the magneto-sensitive layer. [Figure 6] FIG. 6 is a graph showing an example of the spread of the current path of the sensing current in the magneto-sensitive layer. [Figure 7] 7A to 7C are schematic cross-sectional views (part 1) illustrating steps in the method for manufacturing the vertical Hall element according to the first embodiment. [Figure 8] 8A to 8C are schematic cross-sectional views (part 2) illustrating the steps of the method for manufacturing the vertical Hall element according to the first embodiment. [Figure 9] 9A to 9C are schematic cross-sectional views (part 3) illustrating the steps of the method for manufacturing the vertical Hall element according to the first embodiment. [Figure 10] 10A to 10C are schematic cross-sectional views illustrating the manufacturing steps of the vertical Hall element according to the first embodiment (part 4). [Figure 11]11A to 11C are schematic cross-sectional views illustrating steps in the method for manufacturing the vertical Hall element according to the first embodiment (part 5). [Figure 12] 12A to 12C are schematic cross-sectional views illustrating the steps of the method for manufacturing the vertical Hall element according to the first embodiment (part 6). [Figure 13] FIG. 13 is a schematic cross-sectional view showing an example of the shape of the main electrode of the vertical Hall element according to the first embodiment. [Figure 14] FIG. 14 is a schematic plan view showing the structure of a vertical Hall element according to a modified example of the first embodiment. [Figure 15] FIG. 15 is a schematic plan view showing another structure of a vertical Hall element according to a modified example of the first embodiment. [Figure 16] FIG. 16 is a schematic cross-sectional view showing the structure of the vertical Hall element according to the second embodiment. [Figure 17] 17A to 17C are schematic cross-sectional views (part 1) illustrating steps in a method for manufacturing the vertical Hall element according to the second embodiment. [Figure 18] 18A to 18C are schematic cross-sectional views (part 2) illustrating the steps of the method for manufacturing the vertical Hall element according to the second embodiment. [Figure 19] 19A to 19C are schematic cross-sectional views (part 3) illustrating the steps of the method for manufacturing the vertical Hall element according to the second embodiment. [Figure 20] FIG. 20 is a schematic cross-sectional view showing the structure of a vertical Hall element according to another embodiment.

[0008] [Detailed explanation] Next, an embodiment will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are designated by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each part, etc. may differ from the actual ones. Furthermore, it goes without saying that the drawings may include parts with different dimensional relationships or ratios.

[0009] Furthermore, the embodiments described below are merely examples of devices or methods for embodying the technical ideas, and are not intended to limit the shape, structure, arrangement, etc. of the components to those described below. Various modifications can be made to these embodiments within the scope of the claims.

[0010] As shown in FIG. 1 , the vertical Hall element 1 according to the first embodiment includes a conductive first semiconductor layer 20 having a first surface 210 and a second surface 220 facing in the opposite direction to the first surface 210, and a first magnetosensitive layer 301 and second magnetosensitive layers 302A and 302B disposed above the first surface 210. Hereinafter, the second magnetosensitive layer 302A and the second magnetosensitive layer 302B will be referred to as the "second magnetosensitive layer 302" unless otherwise specified. The second magnetosensitive layer 302 is disposed above the first surface 210 at a position spaced apart from the first magnetosensitive layer 301. Furthermore, the first magnetosensitive layer 301 and the second magnetosensitive layer 302 will be referred to as the "magnetosensitive layer 30" unless otherwise specified. The magnetosensitive layer 30 and the first semiconductor layer 20 are electrically connected.

[0011] As shown in FIG. 1 , the thickness direction of the first semiconductor layer 20 (the direction from the second surface 220 toward the first surface 210) is defined as the Z direction. In FIG. 1 , the Z direction is the up-down direction on the paper. The plane perpendicular to the Z direction is defined as the XY plane defined by the X and Y directions. In FIG. 1 , the X direction is the left-right direction on the paper, and the Y direction is the depth direction on the paper. In the present disclosure, in the Z direction, the direction in which the magnetosensitive layer 30 is located as viewed from the first semiconductor layer 20 is defined as the up direction, and the direction in which the first semiconductor layer 20 is located as viewed from the magnetosensitive layer 30 is defined as the down direction. For each layer of the vertical Hall element 1, the surface facing upward is also referred to as the top surface, and the surface facing downward is also referred to as the bottom surface. For example, the first surface 210 is the top surface of the first semiconductor layer 20, and the second surface 220 is the bottom surface of the first semiconductor layer 20.

[0012] A first region 211 is selectively set in a part of the first surface 210 of the first semiconductor layer 20. The magnetosensitive layer 30 is disposed in the first region 211 of the first semiconductor layer 20, and is a mesa-shaped conductive semiconductor having a bottom surface facing the first surface 210 and side surfaces extending in a direction intersecting the first surface 210. As shown in FIG. 1 , the side surfaces of the magnetosensitive layer 30 are exposed. Hereinafter, the area of ​​a cross section of the magnetosensitive layer 30 parallel to the first surface 210 will be referred to as the mesa area. In the vertical Hall element 1, the mesa area may become narrower from the bottom surface upward.

[0013] 1 is perpendicular to the first surface 210. However, the direction from the bottom surface to the top surface of the magnetosensitive layer 30 may be oblique to the first surface 210 rather than perpendicular.

[0014] 1 has a configuration in which two second magneto-sensitive layers 302 are arranged on either side of a first magneto-sensitive layer 301. In other words, the second magneto-sensitive layer 302A, the first magneto-sensitive layer 301, and the second magneto-sensitive layer 302B are arranged in this order along the X direction.

[0015] The mask layer 80 is disposed in the second region 212, which is the remaining region of the first surface 210 of the first semiconductor layer 20 excluding the first region 211. In other words, the mask layer 80 is disposed on the first surface 210 of the first semiconductor layer 20, between the magnetosensitive layers 30. The bottom surfaces of the magnetosensitive layers 30 and the mask layer 80 are flush with each other. No magnetosensitive layer 30 is disposed on the top surface of the mask layer 80. In other words, the mask layer 80 is exposed around the magnetosensitive layers 30.

[0016] The material of the first semiconductor layer 20 and the magnetosensitive layer 30 is a conductive semiconductor. For example, the material of the first semiconductor layer 20 and the magnetosensitive layer 30 may be a Si (silicon) semiconductor or a compound semiconductor such as gallium arsenide (GaAs), indium phosphide (InP), indium antimonide (InSb), or aluminum gallium arsenide (AlGaAs). The following describes, as an example, a case where the material of the first semiconductor layer 20 and the magnetosensitive layer 30 includes GaAs. As will be described later, the magnetosensitive layer 30 is an epitaxially grown layer formed in a first region 211 on a first surface 210 of the first semiconductor layer 20. The first semiconductor layer 20 and the magnetosensitive layer 30 are semiconductors of the same conductivity type.

[0017] The first semiconductor layer 20 may be, for example, a GaAs semiconductor layer doped with n-type impurities. The impurity concentration of the first semiconductor layer 20 is, for example, 1E17 cm -3 ~1E19cm -3 The magneto-sensitive layer 30 may be, for example, a GaAs semiconductor layer doped with n-type impurities. The impurity concentration of the magneto-sensitive layer 30 is, for example, 1E16 cm -3 ~1E17cm -3 The n-type impurity may be, for example, Si, tellurium (Te), zinc (Zn), magnesium (Mg), beryllium (Be), or the like.

[0018] 1 is an insulating layer. For example, the mask layer 80 may be a silicon oxide (SiO2) film or a silicon nitride (SiN) film.

[0019] 1, the vertical Hall element 1 includes a first main electrode 401 disposed on the upper surface of the first magnetosensitive layer 301, a second main electrode 402A disposed on the upper surface of the second magnetosensitive layer 302A, and a second main electrode 402B disposed on the upper surface of the second magnetosensitive layer 302B. Hereinafter, the second main electrode 402A and the second main electrode 402B will be referred to as the "second main electrode 402" unless otherwise specified. Furthermore, the first main electrode 401 and the second main electrode 402 will be referred to as the "main electrode 40" unless otherwise specified. The main electrode 40 may be made of, for example, gold (Au), gold germanium (AuGe) / nickel (Ni), titanium (Ti) / gold (Au), or titanium (Ti) / platinum (Pt) / gold (Au).

[0020] The first main electrode 401 is a first end of a current path of the sense current Is that flows from the first magneto-sensitive layer 301 to the second magneto-sensitive layer 302 via the first semiconductor layer 20. The second main electrode 402 is a second end of the current path of the sense current Is. For example, a power supply that causes the sense current Is to flow from the first main electrode 401 to the second main electrode 402 is provided outside the vertical Hall element 1. The sense current Is does not flow through the mask layer 80, which is an insulating layer.

[0021] The vertical Hall element 1 shown in FIG. 1 further includes a substrate 10 connected to the second surface 220 of the first semiconductor layer 20. The substrate 10 may be, for example, a semi-insulating substrate or an insulating substrate. The substrate 10 may be, for example, a GaAs substrate, an InP substrate, an InSb substrate, or a Si substrate. By using a semi-insulating substrate or an insulating substrate for the substrate 10, electrical insulation of the substrate 10 from the first semiconductor layer 20 is ensured, and the sense current Is does not flow through the substrate 10.

[0022] In the vertical Hall element 1, the sense current Is flowing between the first main electrode 401 and the second main electrode 402 flows along the Z direction, which is the surface normal direction of the first surface 210 of the first semiconductor layer 20 in the first magneto-sensitive layer 301. In other words, the sense current Is flows in a direction perpendicular to the main surface of the substrate 10. As the sense current Is flows in a direction perpendicular to the main surface of the substrate 10, the vertical Hall element 1 can detect a magnetic field parallel to the main surface of the substrate 10, as will be described later.

[0023] 2, the vertical Hall element 1 further includes a pair of first and second Hall electrodes 501 and 502, which are disposed on the upper surface of the first magneto-sensitive layer 301 with the first main electrode 401 sandwiched therebetween. Hereinafter, the first and second Hall electrodes 501 and 502 will be referred to as "Hall electrodes 50" unless otherwise specified. The material of the Hall electrode 50 is the same as that of the main electrode 40 described above.

[0024] A Lorentz force is generated in the vertical Hall element 1 by a magnetic field parallel to the first surface 210 of the first semiconductor layer 20 and a sensing current Is flowing through the first magneto-sensitive layer 301 in a direction perpendicular to the first surface 210. As will be described below, the vertical Hall element 1 is configured so that a Hall output voltage resulting from the Lorentz force can be detected by the Hall electrode 50.

[0025] An example of the operation of the vertical Hall element 1 will be described below with reference to Fig. 2. In Fig. 2, the side surface of the magneto-sensitive layer 30 in the X direction is drawn perpendicular to the first surface 210 of the first semiconductor layer 20.

[0026] In order for the vertical Hall element 1 to detect a magnetic field, a detection current Is flows between the first main electrode 401 and the second main electrode 402 via the first semiconductor layer 20. As described above, the detection current Is flows through the first magneto-sensitive layer 301 in a direction perpendicular to the first surface 210 of the first semiconductor layer 20, and flows through the first semiconductor layer 20 in a direction parallel to the first surface 210. Electrical insulation of the substrate 10 from the first semiconductor layer 20 is ensured so that the detection current Is does not flow through the substrate 10.

[0027] When a magnetic field Bx passes through the first magneto-sensitive layer 301 in a direction parallel to the main surface of the substrate 10 while a sensing current Is flows through the first magneto-sensitive layer 301 in a direction perpendicular to the first surface 210, a Lorentz force f is generated by the sensing current Is and the magnetic field Bx according to Fleming's left-hand rule. Charged particles (carriers) accumulate in the direction of the Lorentz force f, and a Hall output voltage is generated due to the bias of the charged particles.

[0028] In the vertical Hall element 1, a Hall output voltage generated due to the Lorentz force f directed from the first Hall electrode 501 to the second Hall electrode 502 is detected by the Hall electrode 50. In the above-described manner, the vertical Hall element 1 detects the magnetic field Bx.

[0029] In the vertical Hall element 1, the second magneto-sensitive layer 302 is disposed on both sides of the first magneto-sensitive layer 301. Therefore, after flowing through the first magneto-sensitive layer 301, the sensing current Is is divided into a component that flows through the second magneto-sensitive layer 302A and a component that flows through the second magneto-sensitive layer 302B. In other words, in the vertical Hall element 1, a current path is formed that flows from the first magneto-sensitive layer 301 to the second magneto-sensitive layer 302A via the first semiconductor layer 20, and a current path is formed that flows from the first magneto-sensitive layer 301 to the second magneto-sensitive layer 302B via the first semiconductor layer 20.

[0030] The presence of two current paths for the sense current Is prevents the vertical Hall element 1 from erroneously detecting a magnetic field passing perpendicular to the main surface of the substrate 10 (hereinafter also referred to as a "perpendicular magnetic field"). For example, as shown in FIG. 3, when a magnetic field Bz passes perpendicular to the first surface 210, a Lorentz force fa is generated on the component of the sense current Is that flows through the first semiconductor layer 20 from the first magneto-sensitive layer 301 toward the second magneto-sensitive layer 302A and is parallel to the first surface 210, and a Lorentz force fb is generated on the component of the sense current Is that flows through the first semiconductor layer 20 from the first magneto-sensitive layer 301 toward the second magneto-sensitive layer 302B and is parallel to the first surface 210. At this time, as shown in FIG. 3, the directions of the Lorentz forces fa and fb are opposite to each other. Therefore, the directions of the Hall output voltages caused by the Lorentz forces fa and fb are symmetrical and cancel each other out, so no Hall output voltage is generated. Therefore, only the magnetic field Bx passing through the substrate 10 in a direction parallel to the main surface thereof is detected by the vertical Hall element 1.

[0031] In order to increase the sensitivity of the vertical Hall element 1, it is effective to increase the distance over which the sensing current Is flows in the first magneto-sensitive layer 301. That is, it is effective to increase the sensitivity by increasing the thickness of the first magneto-sensitive layer 301. The thickness of the first magneto-sensitive layer 301 is the length from the top surface to the bottom surface along the surface normal direction (Z direction) of the first surface 210 of the first semiconductor layer 20.

[0032] However, when the magnetosensitive layer 30 is formed by etching a semiconductor film into a mesa shape, there is a limit to how thick the magnetosensitive layer 30 can be. This is because the film thickness of the magnetosensitive layer 30 is limited by the film-forming apparatus. For example, when the magnetosensitive layer 30 is formed by epitaxial growth, if the epitaxial growth apparatus has an upper limit on the thickness of the grown film, there is a limit to how thick the magnetosensitive layer 30 can be. For this reason, it is preferable to increase the sensitivity of the vertical Hall element 1 by a method other than increasing the thickness of the magnetosensitive layer 30.

[0033] The sensitivity of the vertical Hall element 1 will be discussed below with reference to the magnetosensitive layer model 30M shown in Fig. 4. The size of the magnetosensitive layer model 30M is as follows: thickness L along the Z direction in which the sensing current Is flows, length t along the X direction in which the magnetic field B flows, and width W along the Y direction perpendicular to the thickness L and length t. The thickness L corresponds to the film thickness of the magnetosensitive layer 30. The length t and width W depend on the cross-sectional area of ​​the region in which the sensing current Is flows.

[0034] When a sensing current Is and a magnetic field B are applied to the magnetosensitive layer model 30M, the carriers are subjected to a Lorentz force of f=q×v×B, where q is the electron charge and v is the drift velocity. A steady state is reached when the force F from the electric field generated by the carrier bias due to the Lorentz force f and the Lorentz force f are balanced. The force F from the electric field is expressed by the following equation (1): F = q × (Vh / W) (1) In equation (1), Vh is the Hall output voltage, while the sense current Is is expressed by equation (2): Is=q×n×v×W×t (2) In Equation (2), n is the carrier concentration.

[0035] When removing the drift velocity v in Equation (2) from f = F and driving the magnetosensitive layer model 30M with a constant current, the Hall output voltage Vh is expressed by the following Equation (3): Vh = I × B / (q × n × t) ···(3)

[0036] When driving the vertical Hall element with a constant voltage, the Hall output voltage Vh is expressed by Equation (4) obtained by substituting the input voltage Vin = Rs × (L / W) × I, where Rs is the sheet resistance of the magnetosensitive layer model 30M, into Equation (3): Vh = μ × (W / L) × Vin × B ···(4) In Equation (4), μ is the carrier mobility. Also, the sheet resistance Rs = 1 / (q × n × μ × t).

[0037] The sensitivity Kh of the magnetosensitive layer model 30M is expressed by the following Equation (5) using the resistivity ρ: Kh = 1 / (q × n × t) = Rs × μ = ρ × μ / t ···(5)

[0038] When the thickness L is short with respect to the width W of the magnetosensitive layer 30, the sensitivity Kh is expressed by Equation (6) obtained by multiplying the sensitivity Kh shown in Equation (5) by the shape effect coefficient K: Kh = 1 / (q × n × t) × K ···(6) For example, when L >> W, K = 1, and when L < W, K = 0.74 × L / W.

[0039] The length t and width W depend on the size of the main electrode 40, and the thickness L corresponds to the film thickness of the magnetosensitive layer 30. In the vertical Hall element 1 where the thickness L is short, it is preferable to prevent the shape effect coefficient K from being applied to the sensitivity Kh. Below, the improvement of the sensitivity Kh of the vertical Hall element 1 will be examined.

[0040] From equation (5), it can be seen that sensitivity Kh can be increased by reducing the carrier concentration n and the length t. Therefore, using Si as the material for the magneto-sensitive layer 30 to reduce the carrier concentration n is effective in increasing sensitivity Kh.

[0041] On the other hand, compound semiconductors such as GaAs have a higher mobility μ than Si, allowing the length t to be reduced. For this reason, the length t may be reduced and the sensitivity Kh increased by using a compound semiconductor as the material for the magneto-sensitive layer 30. For example, when the resistance value of the magneto-sensitive layer 30 is fixed, the length t may be reduced in order to increase the sensitivity Kh.

[0042] Since the sensitivity Kh depends on the carrier concentration n, the vertical Hall element 1 with little change in sensitivity with temperature can be obtained by using a compound semiconductor for the magnetosensitive layer 30. Furthermore, by using a compound semiconductor with a lower resistance than Si for the magnetosensitive layer 30, the vertical Hall element 1 can be realized with resistance and temperature characteristics equivalent to those of a planar Hall element using a compound semiconductor.

[0043] In order to increase the sensitivity of the magnetosensitive layer model 30M, it is effective to reduce the length t and make L≧W. For example, by increasing the thickness L and decreasing the width W, the sensitivity of the magnetosensitive layer model 30M can be increased.

[0044] As shown in equations (5) and (6), the sensitivity Kh depends on the length t and width W of the magnetosensitive layer 30 along the direction of the magnetic field. Therefore, the size of the magnetosensitive layer 30 may be set depending on the sensitivity required for the vertical Hall element 1. However, as shown in FIG. 5, the current path of the sensing current Is flowing through the magnetosensitive layer 30 expands inside the magnetosensitive layer 30 as the mesa area increases.

[0045] FIG. 6 shows an example of the spread of the current path of the sensing current Is flowing through the magneto-sensitive layer 30. In the example shown in FIG. 6, the length of the main electrode 40 in the X direction is 5 μm, and the length from the top surface to the bottom surface of the magneto-sensitive layer 30 is 15 μm. The X axis in FIG. 6 represents the distance from the center of the main electrode 40 toward the side. The Y axis in FIG. 6 represents the distance from the top surface to the bottom surface of the magneto-sensitive layer 30. The ratio (10% to 90%) of the sensing current Is shown in FIG. 6 represents the ratio of the sensing current Is flowing through the magneto-sensitive layer 30 to the entire sensing current Is. For example, focusing on the 90% graph, at a depth of 15 μm from the top surface of the magneto-sensitive layer 30, 90% of the sensing current Is spreads over a range of approximately 20 μm from the center in the X direction.

[0046] If the current path of the sensing current Is flowing through the magneto-sensitive layer of a vertical Hall element widens, the length t and width W increase, resulting in a decrease in sensitivity according to equations (5) and (6). Therefore, suppressing the widening of the current path of the sensing current Is is effective in improving the sensitivity of a vertical Hall element.

[0047] 6 shows that the narrower the mesa area of ​​the magneto-sensitive layer 30, the more the current path of the sensing current Is is suppressed from expanding. Therefore, by narrowing the mesa area of ​​the magneto-sensitive layer 30, the sensitivity of the vertical Hall element is improved.

[0048] In the vertical Hall element 1, the second region 212 excluding the first region 211 of the first surface 210 of the first semiconductor layer 20 is covered with the mask layer 80, which is an insulating layer. For this reason, when a semiconductor film for forming the first magnetosensitive layer 301 (hereinafter also referred to as "magnetosensitive layer film") is formed on the first surface 210 of the first semiconductor layer 20 by epitaxial growth, the first magnetosensitive layer 301 is formed only in the first region 211. For this reason, as will be described later, the mesa area of ​​the first magnetosensitive layer 301 can be made smaller than when the magnetosensitive layer film formed on the entire first surface 210 is etched to form the first magnetosensitive layer 301 in a mesa shape.

[0049] As described above, in the vertical Hall element 1 according to the first embodiment, the mesa-shaped first magneto-sensitive layer 301 is formed only in the first region 211 of the first surface 210 of the first semiconductor layer 20. This narrows the mesa area, thereby suppressing the expansion of the current path of the sensing current Is. In other words, the mask layer 80 narrows the region through which the sensing current Is flows. Therefore, the vertical Hall element 1 can improve sensitivity.

[0050] In the vertical Hall element 1 having the mesa-shaped magnetosensitive layer 30, the mesa-shaped magnetosensitive layer 30 makes it easy to construct the vertical Hall element using a material that is difficult to form a magnetosensitive layer as a buried region in a semiconductor substrate or semiconductor layer. Furthermore, the vertical Hall element 1 having the mesa-shaped magnetosensitive layer 30 suppresses the generation of leakage current and stray capacitance compared to a vertical Hall element having, for example, a configuration in which a p-type semiconductor region and an n-type semiconductor region are adjacent to each other. Therefore, the vertical Hall element 1 can detect magnetic fields with high accuracy.

[0051] 7 to 12, a method for manufacturing the vertical Hall element 1 according to the first embodiment will be described. Note that the method for manufacturing the vertical Hall element 1 described below is an example, and various other manufacturing methods, including modifications thereof, can be used.

[0052] 7, a first semiconductor layer 20 and an insulating layer 800 are formed in this order on the main surface of the substrate 10. The first semiconductor layer 20 is an n-type semiconductor formed by, for example, an epitaxial growth method. The first semiconductor layer 20 has an impurity concentration of, for example, 1E17 cm -3 ~1E19cm -3 The insulating layer 800 may be, for example, an SiO2 film or an SiN film with a thickness of about 0.2 μm to 2 μm.

[0053] Next, a portion of the insulating layer 800 is etched away using photolithography or the like to form a mask layer 80 as shown in FIG. 8. Specifically, a first semiconductor layer 20 is prepared in which a first region 211 is selectively set in a portion of the first surface 210. Then, a mask layer 80 is selectively formed in a second region 212 of the first surface 210 excluding the first region 211. For example, after the insulating layer 800 is formed over the entire surface of the first surface 210 of the first semiconductor layer 20, a portion of the insulating layer 800 is selectively etched away to form the mask layer 80.

[0054] 9, the magnetosensitive layer 30 is formed in the first region 211 of the first surface 210 of the first semiconductor layer 20. That is, a first magnetosensitive layer 301 and a second magnetosensitive layer 302 disposed at a position spaced apart from the first magnetosensitive layer 301 are formed. In this manner, two second magnetosensitive layers 302 are formed with the first magnetosensitive layer 301 sandwiched between them. For example, a magnetosensitive layer film made of a conductive semiconductor of the same conductivity type as the first semiconductor layer 20 is formed on the first surface 210 of the first semiconductor layer 20 by epitaxial growth. When the first semiconductor layer 20 is of the first conductivity type, the magnetosensitive layer film is a first conductivity type semiconductor layer. In the epitaxial growth method, the magnetosensitive layer film is not formed directly on the top surface of the mask layer 80, which is an insulating layer. Therefore, a mesa-shaped magnetosensitive layer 30 whose bottom surface faces the first surface 210 is formed in the first region 211 of the first surface 210 where the mask layer 80 is not formed. The impurity concentration of the magnetosensitive layer is, for example, 1E16 cm -3 ~1E17cm -3 The thickness of the magnetosensitive layer is, for example, about 15 μm.

[0055] When forming the magnetosensitive layer film on the first surface 210 of the first semiconductor layer 20 to form the first magnetosensitive layer 301 in the first region 211, the magnetosensitive layer film may extend in the X direction outside the first region 211. That is, as shown in FIG. 10 , the magnetosensitive layer film 300 may be formed on the upper surface of the mask layer 80. In this case, the magnetosensitive layer film 300 formed on areas other than the upper surface of the first region 211 is removed by etching. The etching may be performed by either dry etching or wet etching. In this etching step, a protective film 510 is formed on the upper surface of the magnetosensitive layer 30 as an etching mask to prevent the magnetosensitive layer 30 from being etched. The protective film 510 may be, for example, a resist film or a SiO2 film.

[0056] For example, when dry etching is used, chlorine (Cl2) gas or silane (SiCl4) gas may be used. When wet etching is used, a mixture of sodium hydroxide (NaOH) and hydrogen peroxide, a mixture of tartaric acid and hydrogen peroxide, a mixture of sulfuric acid and hydrogen peroxide, or the like may be used as the etching solution.

[0057] Next, an insulating film 60 is formed on the surface of the magneto-sensitive layer 30, and then the insulating film 60 is removed from the region where the main electrode 40 and the Hall electrode 50 are to be disposed, as shown in Fig. 11. For example, an opening 600 is formed in the insulating film 60 on the upper surface of the magneto-sensitive layer 30 by photolithography and dry etching.

[0058] Thereafter, a metal film is formed on the upper surface of the insulating film 60 so as to fill the opening 600 of the insulating film 60. Then, as shown in FIG. 12 , the metal film is selectively removed so that only the regions that will become the main electrode 40 and the Hall electrode 50 remain. As a result, the first main electrode 401 is formed on the upper surface of the first magneto-sensitive layer 301, and the second main electrode 402 is formed on the upper surface of the second magneto-sensitive layer 302. The second main electrode 402 is formed above the first surface 210, spaced apart from the first magneto-sensitive layer 301. At this time, although not shown, a pair of Hall electrodes 50 are formed on the upper surface of the first magneto-sensitive layer 301, sandwiching the first main electrode 401 between them. The main electrode 40 and the Hall electrode 50 may have a layered structure, for example, in which a first metal film is an AuGe / Ni film formed by alloying a laminated film of an AuGe film and a Ni film by heat treatment, a second metal film is a TiAu film, and a third metal film is an Au-plated film. This completes the vertical Hall element 1 shown in FIG. 1 .

[0059] In the manufacturing method of the vertical Hall element 1 described above, the magnetosensitive layer 30 is formed by epitaxial growth in a region not covered by the mask layer 80 selectively formed on the first surface 210 of the first semiconductor layer 20. This allows for a smaller area below the magnetosensitive layer 30 than in a method in which the magnetosensitive layer film 300 is formed over the entire first surface 210 of the first semiconductor layer 20 and then selectively etched away using photolithography or other techniques to form the magnetosensitive layer 30. That is, by forming the magnetosensitive layer 30 in an opening formed in the thin mask layer 80, the area below the magnetosensitive layer 30 can be narrowed, thereby narrowing the current path of the sensing current Is. In contrast, in a method in which the magnetosensitive layer film 300, which is thicker than the mask layer 80 and has a thickness of, for example, about 15 μm, is selectively etched away, the area below the magnetosensitive layer 30 is larger than in the manufacturing method according to the embodiment.

[0060] As already explained, suppressing the expansion of the current path of the sense current Is is effective in improving the sensitivity of the vertical Hall element, and therefore, the vertical Hall element 1 can improve the sensitivity.

[0061] An n-type semiconductor doped with n-type impurities can have higher carrier mobility than a p-type semiconductor doped with p-type impurities. For this reason, in the vertical Hall element 1, it is preferable to use n-type impurities as the semiconductor impurities to increase the sensitivity to the magnetic field. Furthermore, the sensing current Is flowing parallel to the first surface 210 does not directly contribute to the detection of the magnetic field B. For this reason, the impurity concentration of the first semiconductor layer 20 is made higher than the impurity concentration of the magnetosensitive layer 30 to reduce the electrical resistance of the sensing current Is flowing parallel to the first surface 210.

[0062] As already explained, the Lorentz force f generated for the component of the detection current Is flowing through the second magneto-sensitive layer 302A and the component of the detection current Is flowing through the second magneto-sensitive layer 302B has opposite directions, thereby preventing erroneous detection of the perpendicular magnetic field. Therefore, in order to equalize the components of the detection current Is flowing through the second magneto-sensitive layer 302A and the second magneto-sensitive layer 302B, it is preferable that the electrical resistances of the current path in the second magneto-sensitive layer 302A and the current path in the second magneto-sensitive layer 302B are equal.

[0063] For this reason, the magneto-sensitive layer 30 is formed so that the second magneto-sensitive layer 302A and the second magneto-sensitive layer 302B have the same height and cross-sectional area. The height of the magneto-sensitive layer 30 is the size in the direction perpendicular to the first surface 210 of the first semiconductor layer 20, and the cross-sectional area is the area of ​​a cross section perpendicular to the height direction. Furthermore, it is preferable that other parameters of the mesa shape that affect the electrical resistance of the second magneto-sensitive layer 302, such as the inclination of the side surface with respect to the first surface 210 and the widths of the bottom and top surfaces, be the same for the second magneto-sensitive layer 302A and the second magneto-sensitive layer 302B.

[0064] The size of the main electrode 40 is restricted by the lower manufacturing limit in electrode process design. Furthermore, the main electrode 40 requires a certain area in order to electrically connect the main electrode 40 to an external power supply, for example, by wire bonding. Therefore, as shown in FIG. 13 , the main electrode 40 may be formed on the upper surface of an insulating film 60 formed on the upper surface of the magneto-sensitive layer 30, with the area required for wire bonding or the like, and the main electrode 40 may be brought into contact with the magneto-sensitive layer 30 through an opening 600 in the insulating film 60. In other words, the size of the opening 600 in the insulating film 60 (hereinafter referred to as "opening size D") is designed to correspond to the size of the magneto-sensitive layer 30 according to the required sensitivity.

[0065] As described above, it is preferable to form the insulating film 60 on the upper surface of the magneto-sensitive layer 30, and to electrically connect the main electrode 40 to the magneto-sensitive layer 30 through an opening 600 provided in the insulating film 60. The perforation size D of the opening 600 in the insulating film 60 is preferably set in consideration of the size of the magneto-sensitive layer 30, which affects the sensitivity Kh of the vertical Hall element 1, and the relationship between the size of the main electrode 40 and the perforation size D. The perforation size D and the width of the bottom of the mesa structure are the effective size of the main electrode 40 of the vertical Hall element 1, which affects the sensitivity Kh.

[0066] <Modification> In the above description, a configuration has been shown in which a pair of second magneto-sensitive layers 302 are arranged with the first magneto-sensitive layer 301 sandwiched between them. As already explained, it is preferable that the current path of the detection current Is is configured so that the two current paths are symmetrical along the direction in which the magnetic field Bx passes, so as to avoid erroneously detecting the perpendicular magnetic field. For this reason, the detection current Is may be branched into two or more paths while maintaining symmetry with respect to the first magneto-sensitive layer 301. In other words, as long as the symmetry of the detection current Is is maintained, the number of second magneto-sensitive layers 302 may be any number other than two.

[0067] For example, as shown in Fig. 14, there may be a plurality of pairs of second magnetosensitive layers 302 arranged on both sides of a first magnetosensitive layer 301. Alternatively, as shown in Fig. 15, the vertical Hall element 1 may include a plurality of electromagnetic layer units 30A, each configured such that a pair of second magnetosensitive layers 302 is arranged with a first magnetosensitive layer 301 sandwiched therebetween.

[0068] 14 and 15, the vertical Hall element 1 can increase the flow of the detection current Is, thereby improving sensitivity. Furthermore, the increase in the current path for the detection current Is can reduce the electrical resistance of the current path. This allows for greater design freedom regarding the detection current Is.

[0069] 14 shows a configuration in which there are two pairs of second magneto-sensitive layers 302 sandwiching the first magneto-sensitive layer 301, but there may be three or more pairs of second magneto-sensitive layers 302. In FIG. 15, a configuration in which the vertical Hall element 1 includes two electromagnetic layer units 30A, but the number of electromagnetic layer units 30A may be three or more.

[0070] (Second embodiment) 16, the vertical Hall element 1 according to the second embodiment has a semiconductor mask layer 80. The vertical Hall element 1 according to the second embodiment differs from the vertical Hall element 1 according to the first embodiment, in that the mask layer 80 is a semiconductor, in that the mask layer 80 is an insulating layer. In other respects, the second embodiment is similar in configuration to the first embodiment shown in FIG.

[0071] 16, the first magneto-sensitive layer 301 and the mask layer 80 have different conductivity types. In other words, when the first magneto-sensitive layer 301 is a first conductivity type semiconductor, the mask layer 80 is a second conductivity type semiconductor. For example, when the first magneto-sensitive layer 301 is an n-type semiconductor, the mask layer 80 is a p-type semiconductor. The following describes, as an example, a case where the first semiconductor layer 20 and the magneto-sensitive layer 30 are n-type semiconductors and the mask layer 80 is a p-type semiconductor.

[0072] Because the first magneto-sensitive layer 301 is an n-type semiconductor and the mask layer 80 is a p-type semiconductor, the sense current Is does not flow between the first magneto-sensitive layer 301 and the mask layer 80. In other words, the sense current Is does not flow through the mask layer 80. Therefore, the only region where the sense current Is flows parallel to the first surface 210 of the first semiconductor layer 20 is the first semiconductor layer 20. This prevents a decrease in the sensitivity accuracy of the vertical Hall element 1, such as an increase in the resistance of the sense current Is flowing parallel to the first surface 210 or detection of a perpendicular magnetic field.

[0073] The mask layer 80 of the vertical Hall element 1 according to the second embodiment has an impurity concentration of, for example, 1E16 cm -3 ~1E18cm -3 The mask layer 80 is a p-type semiconductor with a thickness of about 0.2 to 2 μm. The material of the mask layer 80 may be, for example, indium gallium phosphide (InGaP), aluminum gallium indium phosphide (InGaAlP), or the like.

[0074] In the vertical Hall element 1 according to the second embodiment, the first magneto-sensitive layer 301 is also disposed only in the first region 211 of the first surface 210 of the first semiconductor layer 20, excluding the second region 212 where the mask layer 80 is disposed. This narrows the mesa area of ​​the first magneto-sensitive layer 301, thereby suppressing the expansion of the current path of the sensing current Is. Therefore, the vertical Hall element 1 shown in FIG. 16 can improve sensitivity.

[0075] A method for manufacturing the vertical Hall element 1 according to the second embodiment will be described below with reference to Fig. 17 to Fig. 19. Note that the method for manufacturing the vertical Hall element 1 described below is just an example, and various other manufacturing methods, including modifications thereof, can be used.

[0076] 17, a first semiconductor layer 20 and a semiconductor layer 810 for forming a mask layer 80 are formed in this order on the main surface of a substrate 10. For example, when the first semiconductor layer 20 is an n-type semiconductor, a p-type semiconductor layer 810 is laminated on the first semiconductor layer 20. The n-type first semiconductor layer 20 and the p-type semiconductor layer 810 may be formed successively by, for example, metalorganic chemical vapor deposition (MOCVD).

[0077] Next, a portion of the semiconductor layer 810 is etched away using photolithography or the like, and a mask layer 80 is selectively formed in the second region 212 of the first surface 210 of the first semiconductor layer 20. Thereafter, as shown in FIG. 18 , a magnetosensitive layer film 300 is formed over the entire surface of the first surface 210 of the first semiconductor layer 20 so as to cover the mask layer 80. The magnetosensitive layer film 300 may be formed by epitaxial growth. At this time, the magnetosensitive layer film 300 is formed on the first region 211 of the first surface 210 and on the upper surface of the mask layer 80 of the p-type semiconductor.

[0078] 19, the magnetosensitive layer 300 formed on the upper surface of the mask layer 80 is selectively etched away using the protective film 510 arranged on the upper surface of the magnetosensitive layer 300 above the first region 211 as an etching mask. The protective film 510 may be, for example, a resist film or an SiO2 film. This forms the magnetosensitive layer 30 arranged in the first region 211.

[0079] After removing the magnetosensitive layer film 300 formed on the upper surface of the mask layer 80, the first main electrode 401 and the Hall electrode 50 are formed on the upper surface of the first magnetosensitive layer 301, and the second main electrode 402 is formed on the upper surface of the second magnetosensitive layer 302, in the same manner as described with reference to FIGS. 11 and 12. That is, after forming an insulating film 60 on the surface of the magnetosensitive layer 30, a metal film is formed so as to fill the opening 600 in the insulating film 60. Then, the metal film is selectively removed so that only the regions that will become the main electrode 40 and the Hall electrode 50 remain. This completes the vertical Hall element 1 shown in FIG. 16.

[0080] In forming the magneto-sensitive layer 30, an insulating film or a photoresist film patterned by photolithography may be used as an etching mask. By using a silicon oxide film or the like, which is harder than a photoresist film, as an etching mask, the stability of the shape of the etching mask can be improved.

[0081] The etching process for the magnetosensitive layer film 300 may be a dry etching method or a wet etching method. When etching the magnetosensitive layer film 300 by a wet etching method, by using a p-type semiconductor for the mask layer 80, which has an etching rate different from that of the magnetosensitive layer 30 and the first semiconductor layer 20, the magnetosensitive layer film 300 can be etched until the mask layer 80 is exposed. When etching the magnetosensitive layer film 300 down to the mask layer 80 by a wet etching method, a mixture of NaOH and hydrogen peroxide, a mixture of tartaric acid and hydrogen peroxide, or the like, with a reduced etching rate, may be used as the etching solution.

[0082] In the above, an example has been described in which the magnetosensitive layer film 300 is also formed on the upper surface of the mask layer 80 by epitaxial growth. However, by shifting the lattice constant of the mask layer 80 by a certain amount from the lattice constant of the first semiconductor layer 20, it is possible to prevent the magnetosensitive layer film 300 from growing on the upper surface of the mask layer 80. For example, when the first semiconductor layer 20 and the magnetosensitive layer 30 are made of GaAs, in the step of forming the p-type semiconductor film 81 of InGaP, the lattice constant of the p-type semiconductor film 81 can be made larger than that of GaAs by increasing the ratio of In to Ga. By providing a difference in lattice constant between the mask layer 80 and the first semiconductor layer 20 in this way, the step of selectively etching away the magnetosensitive layer film 300 described with reference to FIG. 18 may be omitted.

[0083] Otherwise, the vertical Hall element 1 according to the second embodiment is substantially the same as that according to the first embodiment, and therefore, redundant description will be omitted. For example, as shown in Fig. 14, there may be a plurality of pairs of second magneto-sensitive layers 302 arranged on both sides of a first magneto-sensitive layer 301. Alternatively, as shown in Fig. 15, there may be a plurality of electromagnetic layer units 30A, each configured such that a pair of second magneto-sensitive layers 302 is arranged with a first magneto-sensitive layer 301 sandwiched therebetween.

[0084] (Other embodiments) Although the present invention has been described above by way of example, the description and drawings that form part of this disclosure should not be understood as limiting the present invention. From this disclosure, various alternative embodiments, examples, and operating techniques will become apparent to those skilled in the art.

[0085] For example, the above description has been given of the vertical Hall element 1 having a configuration in which the second main electrode 402 is arranged on the upper surfaces of a pair of second magnetosensitive layers 302 arranged on either side of the first magnetosensitive layer 301. However, the vertical Hall element 1 does not necessarily have to include the second magnetosensitive layer 302. For example, as shown in FIG. 20 , the second main electrodes 402A and 402B may be arranged directly on the first surface 210 of the first semiconductor layer 20, with the first magnetosensitive layer 301 sandwiched between them, at positions spaced apart from the first magnetosensitive layer 301.

[0086] The vertical Hall element 1 shown in Fig. 20 differs from the vertical Hall element 1 according to the first and second embodiments in that it does not include the second magneto-sensitive layer 302, but is otherwise substantially similar to the first and second embodiments. For example, the mask layer 80 may be an insulating layer or a semiconductor having a different conductivity type from that of the magneto-sensitive layer 30. Furthermore, there may be multiple pairs of second main electrodes 402 arranged on both sides of the first magneto-sensitive layer 301. Alternatively, there may be multiple units each having a pair of second main electrodes 402 arranged with the first magneto-sensitive layer 301 sandwiched between them.

[0087] Although the present disclosure has been described in detail above, it will be apparent to those skilled in the art that the present disclosure is not limited to the embodiments described herein. One or more elements of one embodiment may be combined with one or more elements of another embodiment. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure, as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory, and is not intended to be limiting of the present disclosure.

[0088] [Note] The technical ideas that can be understood from the present disclosure are described below. Note that, for the purpose of aiding understanding and not intending to be limiting, the components described in the appendices are given the reference numerals of the corresponding components in the embodiments. The reference numerals are shown as examples to aid understanding, and the components described in each appendix should not be limited to the components indicated by the reference numerals.

[0089] (Appendix 1) The vertical Hall element 1 has a first surface 210 and a second surface 220 facing in the opposite direction to the first surface 210. The vertical Hall element 1 includes a conductive first semiconductor layer 20 having a first region 211 selectively set in a part of the first surface 210, a mask layer 80 made of an insulating layer or a conductive semiconductor having a different conductivity type from that of the first semiconductor layer 20 and disposed in a second region 212 of the first surface 210 excluding the first region 211, and a first magneto-sensitive layer 301 made of a conductive semiconductor of the same conductivity type as the first semiconductor layer 20 and disposed in the first region 211 of the first semiconductor layer 20. The first magneto-sensitive layer 301 has a mesa shape with its bottom surface facing the first surface 210 and is made of a conductive semiconductor of the same conductivity type as the first semiconductor layer 20. According to the vertical Hall element 1 described in Supplementary Note 1, the mask layer 80 narrows the region through which the sense current Is flows through the first magneto-sensitive layer 301. Therefore, the vertical Hall element 1 can suppress the expansion of the current path of the sense current Is.

[0090] (Appendix 2) In the vertical Hall element 1 described in Supplementary Note 1, the first magneto-sensitive layer 301 is an epitaxially grown layer. According to the vertical Hall element 1 described in Supplementary Note 2, the first magneto-sensitive layer 301 can be selectively disposed in the first region 211 of the first semiconductor layer 20.

[0091] (Appendix 3) In the vertical Hall element 1 described in Supplementary Note 1 or 2, the mask layer 80 is exposed around the first magnetosensitive layer 301. In the vertical Hall element 1 described in Supplementary Note 3, the magnetosensitive layer film 300 is not formed on the upper surface of the mask layer 80, so that the mask layer 80 is exposed in the remaining area of ​​the area where the first magnetosensitive layer 301 is disposed.

[0092] (Appendix 4) In the vertical Hall element 1 according to any one of Supplementary Notes 1 to 3, the mask layer 80 is an insulating layer. In the vertical Hall element 1 according to Supplementary Note 4, the magnetosensitive layer 300 is not formed on the upper surface of the mask layer 80 by epitaxial growth.

[0093] (Appendix 5) In the vertical Hall element 1 described in any one of Supplementary Notes 1 to 3, the first magneto-sensitive layer 301 is a semiconductor of the first conductivity type, and the mask layer 80 is a semiconductor of the second conductivity type. In the vertical Hall element 1 described in Supplementary Note 5, no sense current Is flows between the first magneto-sensitive layer 301 and the mask layer 80.

[0094] (Appendix 6) The vertical Hall element 1 described in any one of Supplementary Notes 1 to 5 further includes a first main electrode 401 disposed on the upper surface of the first magneto-sensitive layer 301, and a second main electrode 402 disposed above the first surface 210 at a position spaced apart from the first magneto-sensitive layer 301. According to the vertical Hall element 1 described in Supplementary Note 6, the first main electrode 401 serves as a first end of a current path, the second main electrode 402 serves as a second end of the current path, and the sense current Is flows in a direction perpendicular to the main surface of the substrate 10.

[0095] (Appendix 7) The vertical Hall element 1 described in Supplementary Note 6 further includes a pair of Hall electrodes 50 disposed on the upper surface of the first magneto-sensitive layer 301 with the first main electrode 401 sandwiched therebetween. According to the vertical Hall element 1 described in Supplementary Note 7, the Hall output voltage caused by the Lorentz force f generated by the magnetic field parallel to the first surface 210 of the first semiconductor layer 20 and the sensing current Is flowing through the first magneto-sensitive layer 301 can be detected by the Hall electrodes 50.

[0096] (Appendix 8) The vertical Hall element 1 described in Supplementary Note 6 or 7 further includes a mesa-shaped conductive semiconductor second magneto-sensitive layer 302 disposed above the first surface 210 of the first semiconductor layer 20 at a position spaced apart from the first magneto-sensitive layer 301, with its bottom surface facing the first surface 210. The vertical Hall element 1 described in Supplementary Note 8 has a second main electrode 402 disposed on the top surface of the mesa-shaped second magneto-sensitive layer 302.

[0097] (Appendix 9) In the vertical Hall element 1 described in Supplementary Note 8, two second magneto-sensitive layers 302 are arranged on either side of a first magneto-sensitive layer 301. In the vertical Hall element 1 described in Supplementary Note 9, the presence of two current paths for the detection current Is prevents erroneous detection of a magnetic field passing perpendicular to the main surface of the substrate 10.

[0098] (Appendix 10) In the vertical Hall element 1 described in any one of Supplementary Notes 1 to 9, the first magneto-sensitive layer 301 contains a compound semiconductor. According to the vertical Hall element 1 described in Supplementary Note 10, the first magneto-sensitive layer 301 is made of a compound semiconductor, which results in a vertical Hall element 1 having higher sensitivity than when the first magneto-sensitive layer 301 is made of silicon, and having good temperature characteristics with little change in sensitivity with respect to temperature.

[0099] (Appendix 11) In the vertical Hall element 1 described in Supplementary Note 10, the first magneto-sensitive layer 301 contains gallium arsenide. When the material of the first magneto-sensitive layer 301 is gallium arsenide, a compound semiconductor, the vertical Hall element 1 has high sensitivity and good temperature characteristics.

[0100] (Appendix 12) The vertical Hall element 1 according to any one of Supplementary Notes 1 to 11 further comprises an insulating substrate 10 connected to the second surface 220 of the first semiconductor layer 20. In the vertical Hall element 1 according to Supplementary Note 12, the electrical insulation of the substrate 10 from the first semiconductor layer 20 is ensured, and the sense current Is does not flow through the substrate 10.

[0101] (Appendix 13) A method for manufacturing a vertical Hall element 1 includes the steps of: preparing a conductive first semiconductor layer 20 having a first surface 210 and a second surface 220 facing in the opposite direction to the first surface 210, the first region 211 being selectively set in a part of the first surface 210; selectively forming a mask layer 80 made of an insulating layer or a conductive semiconductor having a conductivity type different from that of the first semiconductor layer 20 in a second region 212 of the first surface 210 excluding the first region 211; and forming a first magneto-sensitive layer 301 made of a conductive semiconductor of the same conductivity type as the first semiconductor layer 20 and having a mesa shape whose bottom surface faces the first surface 210 in the first region 211 of the first semiconductor layer 20. According to the method for manufacturing a vertical Hall element described in Appendix 13, the mask layer 80 narrows the region through which a sense current Is flows in the first magneto-sensitive layer 301. This makes it possible to manufacture a vertical Hall element 1 that suppresses the expansion of the current path of the sense current Is.

[0102] (Appendix 14) In the method for manufacturing a vertical Hall element described in Supplementary Note 13, the first magnetosensitive layer 301 is formed by epitaxial growth. In the method for manufacturing a vertical Hall element described in Supplementary Note 14, the first magnetosensitive layer 301 can be selectively formed in the first region 211 of the first semiconductor layer 20.

[0103] (Appendix 15) In the method for manufacturing a vertical Hall element described in Appendix 13 or 14, the mask layer 80 is an insulating layer, and after the insulating layer 800 is formed on the entire first surface 210 of the first semiconductor layer 20, a part of the insulating layer 800 is selectively etched away to form the mask layer 80. According to the method for manufacturing a vertical Hall element described in Appendix 15, the magnetosensitive layer 300 is not formed on the upper surface of the mask layer 80 by an epitaxial growth method.

[0104] (Appendix 16) In the method for manufacturing a vertical Hall element described in Appendix 13 or 14, the first magneto-sensitive layer 301 is a first conductivity type semiconductor, and the mask layer 80 is a second conductivity type semiconductor. After selectively forming the mask layer 80, a first conductivity type semiconductor layer is formed on the entire first surface 210 so as to cover the mask layer 80. Thereafter, the first conductivity type semiconductor layer formed on the mask layer 80 is removed, and the first magneto-sensitive layer 301 is selectively formed. According to the method for manufacturing a vertical Hall element described in Appendix 16, a vertical Hall element 1 can be manufactured in which no sense current Is flows between the first magneto-sensitive layer 301 and the mask layer 80.

[0105] (Appendix 17) In the method for manufacturing a vertical Hall element described in any one of Supplementary Notes 13 to 16, a first main electrode 401 is formed on an upper surface of the first magneto-sensitive layer 301 facing in the opposite direction to the bottom surface, and a second main electrode 402 is formed above the first surface 210 at a position spaced apart from the first magneto-sensitive layer 301. According to the method for manufacturing a vertical Hall element described in Supplementary Note 17, it is possible to manufacture a vertical Hall element 1 in which the first main electrode 401 serves as a first end of a current path, the second main electrode 402 serves as a second end of the current path, and the sense current Is flows in a direction perpendicular to the main surface of the substrate 10.

[0106] (Appendix 18) In the method for manufacturing a vertical Hall element described in Appendix 17, a pair of Hall electrodes 50 are formed on the upper surface of the first magneto-sensitive layer 301 with the first main electrode 401 sandwiched therebetween. According to the method for manufacturing a vertical Hall element described in Appendix 18, it is possible to manufacture a vertical Hall element 1 in which the Hall output voltage caused by the Lorentz force f generated by a magnetic field parallel to the first surface 210 of the first semiconductor layer 20 and a sensing current Is flowing through the first magneto-sensitive layer 301 is detected by the Hall electrodes 50.

[0107] (Appendix 19) In the method for manufacturing a vertical Hall element described in Appendix 17 or 18, a mesa-shaped second magneto-sensitive layer 302 made of a conductive semiconductor and having a bottom surface facing the first surface 210 is formed above the first surface 210 at a position spaced apart from the first magneto-sensitive layer 301, and the second main electrode 402 is formed on an upper surface facing the bottom surface of the second magneto-sensitive layer 302. According to the method for manufacturing a vertical Hall element described in Appendix 19, a vertical Hall element 1 can be manufactured in which the first main electrode 401 serves as a first end of a current path, the second main electrode 402 serves as a second end of the current path, and the sense current Is flows in a direction perpendicular to the main surface of the substrate 10.

[0108] (Appendix 20) In the method for manufacturing a vertical Hall element described in Appendix 19, two second magneto-sensitive layers 302 are formed sandwiching a first magneto-sensitive layer 301. According to the method for manufacturing a vertical Hall element described in Appendix 20, there are two current paths for the detection current Is, so that the vertical Hall element 1 can be manufactured in such a way that erroneous detection of a magnetic field passing perpendicular to the main surface of the substrate 10 is prevented. [Explanation of symbols]

[0109] 1 Vertical Hall element 10 Substrate 20 First semiconductor layer 80 mask layers 210 Page 1 211 First area 212 Second area 220 2nd page 300 Magnetically sensitive layer film 301 First magnetically sensitive layer 302A, 302B second magnetically sensitive layer 401 1st main electrode 402A, 402B 2nd main electrode 501 First Hall electrode 502 Second Hall electrode 800 insulating layer 810 Semiconductor layer

Claims

1. a conductive first semiconductor layer having a first surface and a second surface facing in a direction opposite to the first surface, and a first region selectively set in a part of the first surface; a mask layer of an insulating layer or a conductive semiconductor having a conductivity type different from that of the first semiconductor layer, the mask layer being disposed in a second region of the first surface excluding the first region; a first magnetosensitive layer that is disposed in the first region of the first semiconductor layer, has a mesa shape with a bottom surface facing the first surface, and is made of a conductive semiconductor of the same conductivity type as the first semiconductor layer; A vertical Hall element comprising:

2. 2. The vertical Hall element according to claim 1, wherein the first magneto-sensitive layer is an epitaxially grown layer.

3. 2. The vertical Hall element according to claim 1, wherein the mask layer is exposed around the first magneto-sensitive layer.

4. 2. The vertical Hall element according to claim 1, wherein the mask layer is an insulating layer.

5. the first magnetosensitive layer is a first conductivity type semiconductor, the mask layer is a second conductivity type semiconductor; 2. The vertical Hall element according to claim 1.

6. a first main electrode disposed on an upper surface of the first magnetosensitive layer facing in a direction opposite to the bottom surface; a second main electrode disposed above the first surface at a position spaced apart from the first magnetosensitive layer; The vertical Hall element according to claim 1 , further comprising:

7. a pair of Hall electrodes disposed on the upper surface of the first magnetosensitive layer with the first main electrode interposed therebetween; 7. The vertical Hall element according to claim 6, wherein the Hall electrode is configured to detect a Hall output voltage resulting from a Lorentz force generated by a magnetic field parallel to the first surface of the first semiconductor layer and a detection current flowing between the first main electrode and the second main electrode via the first magneto-sensitive layer.

8. a second magneto-sensitive layer made of a conductive semiconductor and having a mesa shape, the second magneto-sensitive layer being disposed above the first surface at a position spaced apart from the first magneto-sensitive layer and having a bottom surface facing the first surface; the second main electrode is disposed on an upper surface of the second magnetosensitive layer opposite to the bottom surface; 7. The vertical Hall element according to claim 6.

9. 9. The vertical Hall element according to claim 8, wherein two of the second magneto-sensitive layers are disposed with the first magneto-sensitive layer sandwiched therebetween.

10. 6. The vertical Hall element according to claim 1, wherein the first magneto-sensitive layer includes a compound semiconductor.

11. The vertical Hall element according to claim 10 , wherein the first magneto-sensitive layer comprises gallium arsenide.

12. The vertical Hall element according to claim 1 , further comprising an insulating substrate connected to the second surface of the first semiconductor layer.

13. preparing a conductive first semiconductor layer having a first surface and a second surface facing in a direction opposite to the first surface, and a first region selectively set in a part of the first surface; selectively forming an insulating layer or a mask layer made of a conductive semiconductor having a conductivity type different from that of the first semiconductor layer in a second region excluding the first region of the first surface; a first magnetosensitive layer having a mesa shape with a bottom surface facing the first surface and made of a conductive semiconductor of the same conductivity type as the first semiconductor layer is formed in the first region of the first semiconductor layer; A method for manufacturing a vertical Hall element comprising:

14. The method for manufacturing a vertical Hall element according to claim 13, wherein the first magneto-sensitive layer is formed by epitaxial growth.

15. the mask layer is an insulating layer, The method for manufacturing a vertical Hall element according to claim 13 , further comprising the steps of: forming an insulating film on the entire first surface of the first semiconductor layer; and then selectively etching away a portion of the insulating film to form the mask layer.

16. the first magnetosensitive layer is a first conductivity type semiconductor, the mask layer is a second conductivity type semiconductor; After selectively forming the mask layer, a first conductivity type semiconductor layer is formed on the entire first surface so as to cover the mask layer; The method for manufacturing a vertical Hall element according to claim 13, wherein the first magneto-sensitive layer is selectively formed by removing the first conductive type semiconductor layer formed on the mask layer.

17. a first main electrode is formed on an upper surface of the first magnetosensitive layer facing in a direction opposite to the bottom surface; a second main electrode is formed above the first surface at a position spaced apart from the first magnetosensitive layer; The method for manufacturing a vertical Hall element according to claim 13 , further comprising:

18. The method for manufacturing a vertical Hall element according to claim 17 , further comprising forming a pair of Hall electrodes on the upper surface of the first magneto-sensitive layer with the first main electrode sandwiched therebetween.

19. a second magneto-sensitive layer made of a conductive semiconductor and having a mesa shape with a bottom surface facing the first surface, formed above the first surface at a position spaced apart from the first magneto-sensitive layer; The second main electrode is formed on an upper surface of the second magnetosensitive layer opposite to the bottom surface. The method for manufacturing a vertical Hall element according to claim 17, further comprising:

20. The method for manufacturing a vertical Hall element according to claim 19, wherein the second magneto-sensitive layers are formed two apart with the first magneto-sensitive layer sandwiched therebetween.

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