Hall element, method for manufacturing same, and semiconductor device

Abstract

The invention provides a Hall element capable of preventing moisture from permeating from an interface between an ohmic contact layer and a protective layer, a manufacturing method thereof and a semiconductor device. A Hall element is provided with: a substrate; a magnetic sensing layer disposed on the top surface of the substrate; a protective layer that covers the magnetic induction layer and has an opening that exposes a specific region of the magnetic induction layer; the ohmic contact layer is electrically connected with the magnetic induction layer exposed from the opening, and a part of the ohmic contact layer is connected with the protective layer around the opening; and a first metal layer which is disposed on the ohmic contact layer, and which is partially in contact with the protective layer around the ohmic contact layer.

Description

Technical Field

[0001] The present disclosure relates to a Hall element, a manufacturing method thereof, and a semiconductor device. Background Art

[0002] The Hall element is an element that converts a magnetic signal into an electrical signal and detects it. It is used in a wide range of fields such as current sensors and motor rotation angle detection sensors. As a structure of an existing Hall element, for example, Patent Document 1 discloses a Hall element in which a magnetically sensitive layer includes an n-type semiconductor formed by adding Si (silicon) as an impurity to GaAs (gallium arsenide). The Hall element is arranged on a substrate in a cross-shaped manner when the magnetically sensitive layer is viewed from above, and electrodes are arranged on the surface of each end of the cross-shaped magnetically sensitive layer and electrically connected, and the surface of the magnetically sensitive layer where no electrode is arranged is covered with a protective layer such as SiN (silicon nitride).

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2017-50394 Summary of the invention

[0006] If the Hall element is placed in a high temperature and high humidity environment, moisture may penetrate through the interface between the ohmic contact layer electrically connected to the end of the magnetically sensitive layer of the Hall element and the protective layer covering the surface of the magnetically sensitive layer and reach the magnetically sensitive layer, thereby degrading the magnetically sensitive layer.

[0007] The present disclosure is proposed in view of the above-mentioned actual situation, and its purpose is to provide a Hall element and a manufacturing method thereof and a semiconductor device that prevent moisture from penetrating from the interface between the ohmic contact layer and the protective layer.

[0008] The Hall element disclosed herein comprises: a substrate; a magnetically sensitive layer, which is arranged on the top surface of the substrate; a protective layer, which covers the magnetically sensitive layer and has an opening that exposes a specific area of ​​the magnetically sensitive layer; an ohmic contact layer, which is electrically connected to the magnetically sensitive layer exposed from the opening and a portion of which is in contact with the protective layer around the opening; and a metal layer, which is arranged on the ohmic contact layer and a portion of which is in contact with the protective layer around the ohmic contact layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a top view of the Hall element.

[0010] Figure 2 It is a cross-sectional view of the Hall element.

[0011] Figure 3 This is a cross-sectional view of the main parts of the Hall element.

[0012] Figure 4It is an enlarged cross-sectional view of the Hall element.

[0013] Figure 5 It is a process flow chart of the manufacturing method of the Hall element.

[0014] Figure 6 It is a process flow chart of the manufacturing method of the Hall element.

[0015] Figure 7 It is a process flow chart of the manufacturing method of the Hall element.

[0016] Figure 8 It is a process flow chart of the manufacturing method of the Hall element.

[0017] Fig. 9 It is a process flow chart of the manufacturing method of the Hall element.

[0018] Fig.10 It is a process flow chart of the manufacturing method of the Hall element.

[0019] Fig.11 It is a process flow chart of the manufacturing method of the Hall element.

[0020] Fig.12 It is a process flow chart of the manufacturing method of the Hall element.

[0021] Fig.13 It is a process flow chart of the manufacturing method of the Hall element.

[0022] Fig.14 It is a process flow chart of the manufacturing method of the Hall element. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of a Hall element, a method for manufacturing the Hall element, and a semiconductor device will be described in detail with reference to the accompanying drawings. Figure 1 1 is a plan view of the Hall element 10 according to the present embodiment. Figure 2 is to use Figure 1 A cross-sectional view of the Hall element 10 cut along the cutting line II-II in FIG.

[0024] The Hall element 10 has a top surface 11a of a substrate 11 that is substantially rectangular in plan view, and a magnetically sensitive layer 12 is arranged so as to form a cross shape in plan view extending in two diagonal directions of the substantially rectangular shape. A protective layer 13 is formed so as to cover the top surface 11a of the substrate 11 on which the magnetically sensitive layer 12 is arranged, and an opening 13a is formed in the protective layer 13 so as to expose a specific region including an end portion of the cross-shaped magnetically sensitive layer 12 and a portion of the top surface 11a of the substrate 11 adjacent to the end portion.

[0025] In addition, in the Hall element 10, electrodes 17 electrically connected to the ends of the magnetically sensitive layer 12 are arranged so as to cover the openings 13a of the protective layer 13. Between the bottom surface of the electrode 17 and the region exposed from the openings 13a of the protective layer 13, that is, a specific region including the end of the magnetically sensitive layer 12 and a portion of the top surface 11a of the substrate 11 adjacent to the end, an ohmic contact layer 14 forming a eutectic with the magnetically sensitive layer 12, a first metal layer 15 for preventing the ohmic contact layer 14 from balling up, and a second metal layer 16 forming a base for plating are sequentially stacked and interposed, so that the magnetically sensitive layer 12 and the electrode 17 are electrically connected.

[0026] Reference Figure 1 , the electrode 17 is formed by the first electrode 17 1 To the fourth electrode 17 4 Among these electrodes, for example, the first electrode 17 which is opposite to the first electrode 17 in a diagonal direction 1 and the fourth electrode 17 4 The input terminal is formed, and the second electrode 17 opposite to the other diagonal direction is 2 and the third electrode 17 3 In the magnetically sensitive layer 12, the first electrode 17 1 and the fourth electrode 17 4 The carriers moving on the path between the pair of input terminals are subjected to a Lorentz force in a direction perpendicular to the moving direction by the magnetic field penetrating the magnetic sensitive layer 12, and the second electrode 17 facing in a direction substantially perpendicular to the moving direction is subjected to a Lorentz force. 2 and the third electrode 17 3 An electromotive force corresponding to the intensity of the magnetic field is detected at such an output terminal.

[0027] In the Hall element 10, the substrate 11 includes GaAs (gallium arsenide) which is a III-V compound semiconductor. The magnetically sensitive layer 12 includes an n-type compound semiconductor of GaAs to which at least one of Si (silicon) and Te (tellurium) is added as an impurity. The magnetically sensitive layer 12 is doped with impurities at a low concentration so as to increase the mobility of carriers in order to ensure the sensitivity of detecting magnetism.

[0028] The protective layer 13 includes SiN (silicon nitride). The protective layer 13 covers the top surface 11a of the substrate 11 and the magnetically sensitive layer 12 except for the region where the opening 13a is formed, and protects the top surface 11a of the substrate 11 and the magnetically sensitive layer 12. 1 To the fourth electrode 17 4 These four electrodes are electrically connected to the four ends of the magnetically sensitive layer 12 , respectively, and provide a connection path between the Hall element 10 and the outside.

[0029] The ohmic contact layer 14 includes an alloy of AuGeNi (gold germanium nickel) and forms a eutectic with the magnetically sensitive layer 12, thereby ensuring a stable ohmic contact with the magnetically sensitive layer 12. The first metal layer 15 is formed of Ti (titanium) to prevent the deterioration of conductivity and the like due to the granular formation of the alloy components constituting the first metal layer 15. The second metal layer 16 includes Au (gold) and forms a gold-plated base layer. The electrode 17 includes gold plating formed by using the second metal layer 16 as a plated base layer in a manner that covers the opening 13a of the protective layer 13.

[0030] Figure 3 is a cross-sectional view of the main part of the Hall element 10, which is equivalent to Figure 2 The surface of the magnetic sensitive layer 12 is covered by the protective layer 13 except for the opening 13a formed in the protective layer 13. The opening 13a of the protective layer 13 is formed in a region including the end of the magnetic sensitive layer 12 and is covered by the electrode 17. Between the surface of the end of the magnetic sensitive layer 12 and the bottom surface of the electrode 17, there is interposed a laminated body in which the ohmic contact layer 14, the first metal layer 15, and the second metal layer 16 are laminated in sequence. The laminated body extends from the opening 13a in contact with the protective layer 13 formed on the top surface of the magnetic sensitive layer 12, and is in contact with the island portion 20 formed in the surface of the protective layer 13 just below the side surface of the electrode 17 and in which the first metal layer 15 and the second metal layer 16 are laminated.

[0031] Figure 4 1 is an enlarged cross-sectional view of the vicinity of the island portion 20 in the Hall element 10. On the surface of the protective layer 13, an island portion 20 formed by stacking the first metal layer 15 and the second metal layer 16 is formed just below the side surface of the electrode 17. A portion of the root portion including the island portion 20 is located inward of the side surface of the electrode 17, and the remaining portion of the island portion 20 protrudes from the side surface of the electrode 17. The end surface 20b of the island portion 20 protruding from the side surface of the electrode 17 has an eaves-like shape that protrudes forward as the height from the surface of the protective layer 13 increases.

[0032] The island portion 20 is formed inside the electrode 17 in contact with a main body formed by stacking the first metal layer 15 and the second metal layer 16 on the ohmic contact layer 14. Specifically, the root of the island portion 20 located inside the side surface of the electrode 17 is formed in a manner facing and contacting the end of the stacked body of the ohmic contact layer 14, the first metal layer 15, and the second metal layer 16 formed on the surface of the protective layer 13. The end surface 14a of the ohmic contact layer 14 facing the root of the island portion 20 has an eaves-like shape that protrudes forward as the height from the surface of the protective layer 13 increases. The gap formed by the eaves-like end surface 14a of the ohmic contact layer 14, the end surface 20a of the root of the island portion 20, and the surface of the protective layer 13 is filled with gold plating constituting the electrode 17, thereby forming a metal filling portion 21.

[0033] In the Hall element 10, an island portion 20 is formed at the boundary between the surface of the protective layer 13 formed on the surface of the magnetically sensitive layer 12 and the side surface of the electrode 17. The island portion 20 seals the interface between the ohmic contact layer 14 and the protective layer 13, and prevents moisture from penetrating from the interface between the ohmic contact layer 14 and the protective layer 13. Since the titanium of the first metal layer 15 constituting the island portion 20 has a high adhesion property with the silicon nitride constituting the protective layer 13, the island portion 20 and the protective layer 13 can be reliably sealed.

[0034] In addition, a gold-plated metal filling portion 21 is formed in the gap between the island portion 20 and the ohmic contact layer 14. The metal filling portion 21 is in contact with the interface between the ohmic contact layer 14 and the protective layer 13, and seals the interface between the ohmic contact layer 14 and the protective layer 13. Therefore, even if the island portion 20 cannot prevent moisture from penetrating, the metal filling portion 21 can be used for sealing, thereby reliably preventing moisture from penetrating from the interface between the ohmic contact layer 14 and the protective layer 13.

[0035] In the Hall element 10 , the substrate 11 and the magnetically sensitive layer 12 include GaAs of the III-V group, but the present invention is not limited thereto. For example, other types of compound semiconductors such as InSb (indium antimonide) and InAs (indium arsenide) may be used.

[0036] Next, refer to Figures 5 to 14 The manufacturing method of the Hall element 10 is described with reference to the process flow chart. Figure 3 Likewise, Figures 5 to 14 It is equivalent to Figure 2 The main part of the Hall element 10 is shown in region III.

[0037] like Figure 5 As shown in FIG. 1 , a magnetically sensitive layer 12 is formed on a top surface 11a of a substrate 11 including GaAs (gallium arsenide), and the magnetically sensitive layer 12 includes an n-type compound semiconductor of GaAs to which at least one of Si (silicon) and Te (tellurium) is added as an impurity. As described above, the magnetically sensitive layer 12 is formed to have a cross shape in a top view extending in two diagonal directions of the top surface 11a of the substrate 11 which is substantially rectangular in a top view. Next, a protective layer 13 including SiN is formed so as to cover the top surface 11a of the substrate 11 on which the magnetically sensitive layer 12 is arranged. An opening 13a is formed in the protective layer 13 so that a specific region including an end portion of the cross-shaped magnetically sensitive layer 12 and a portion of the top surface 11a of the substrate 11 adjacent to the end portion is exposed.

[0038] On the top surface 11a of the substrate 11 on which the protective layer 13 is formed, an ohmic contact layer 14 including an alloy of AuGeNi (gold germanium nickel) is formed so as to cover the protective layer 13. Furthermore, on the surface of the ohmic contact layer 14, a first mask 31 including a resin is formed in a specific pattern such as covering a specific area such as an opening 13a formed in the protective layer 13 and its surroundings.

[0039] like Figure 6 As shown, the first etching solution 32 is used to Figure 5 The ohmic contact layer 14 having the first mask 31 formed on the surface is etched. The ohmic contact layer 14 is covered by the first mask 31 in a specific area such as the opening 13a formed in the protective layer 13 or its surroundings. Therefore, the ohmic contact layer 14 in the area not covered by the first mask 31 and exposed is etched and removed by the first etching solution 32.

[0040] In addition, the ohmic contact layer 14 covered by the first mask 31 at the end of the protective layer 13 is also removed by etching from the end of the first mask 31 to a specific depth using the first etching solution 32 that penetrates between the surface of the protective layer 13 and the first mask 31. Here, the protective layer 13 made of SiN has an affinity for the first etching solution 32 compared to the first mask 31 made of resin, and the etching of the ohmic contact layer 14 progresses faster as it is farther away from the first mask 31 and closer to the protective layer 13. Therefore, the end face 14a of the ohmic contact layer 14 between the protective layer 13 and the first mask 31 is formed in an eave-like shape that protrudes forward as the height increases from the protective layer 13 toward the first mask 31.

[0041] like Figure 7 As shown, in Figure 6 After etching the ohmic contact layer 14, the first mask 31 is removed. The end of the protective layer 13 formed on the surface of the magnetic sensitive layer 12 and the opening 13a of the protective layer 13 are covered by the ohmic contact layer 14. The end surface 14a of the ohmic contact layer 14 covering the end of the protective layer 13 is formed in an eaves-like shape that protrudes forward as the height from the protective layer 13 increases.

[0042] like Figure 8 As shown, by heating in a heating furnace, a eutectic is formed between the magnetic sensitive layer 12 and the ohmic contact layer 14 made of an alloy of AuGeNi in contact with the magnetic sensitive layer 12 in the opening 13a of the protective layer 13. Reference numeral 33 in the figure indicates a high temperature environment in the heating furnace.

[0043] like Fig. 9 As shown, in Figure 8After forming a eutectic between the magnetic sensitive layer 12 and the ohmic contact layer 14, the first metal layer 15 containing Ti for preventing the ohmic contact layer 14 from being balled, and the second metal layer 16 containing Au as a base layer of gold plating are stacked. Since the end of the protective layer 13 formed on the surface of the magnetic sensitive layer 12 and the opening 13a of the protective layer 13 are covered by the ohmic contact layer 14, the first metal layer 15 and the second metal layer 16 are formed on the surface of the ohmic contact layer 14, forming a laminated body in which the ohmic contact layer 14, the first metal layer 15 and the second metal layer 16 are stacked in sequence. In the protective layer 13, in the area not covered by the ohmic contact layer 14 except the end, the first metal layer 15 and the second metal layer 16 are directly stacked on the surface of the protective layer 13. Directly below the eaves-shaped end face 14a of the ohmic contact layer 14 formed at the end of the protective layer 13 and on the surface of the protective layer 13, a gap 19 with a triangular cross-section is formed that connects to the end faces of the first metal layer 15 and the second metal layer 16 directly formed on the surface of the protective layer 13.

[0044] like Fig.10 As shown, in Fig. 9 The surfaces of the first metal layer 15 and the second metal layer 16 formed on the surface of the protective layer 13 are formed at a specific height in a manner that has a specific spacing from the laminated body composed of the ohmic contact layer 14, the first metal layer 15 and the second metal layer 16 formed at the end of the protective layer 13, and the second mask 34 containing resin is formed at a specific height.

[0045] like Fig.11 As shown, from Fig.10 The electrode 17 is continuously formed by gold plating on the surface of the laminate of the ohmic contact layer 14, the first metal layer 15, and the second metal layer 16 covering the end of the protective layer 13 and the opening 13a of the protective layer 13, and on the surface of the first metal layer 15 and the second metal layer 16 formed on the surface of the magnetic sensitive layer 12 and the region where the second mask 34 is not formed so as to cover the second metal layer 16 forming the plated base layer. When the electrode 17 is continuously formed by gold plating, the gap 19 formed just below the eaves-shaped end surface 14a of the ohmic contact layer 14 formed on the surface of the protective layer 13 is also filled with gold plating, thereby forming a metal filling portion 21. Fig.11 The electrode 17 shown is formed Figure 1 The third electrode 17 shown 3 and the second electrode 17 2 .

[0046] exist Fig.12 in Fig.11 After forming the electrode 17 by gold plating, the second mask 34 is removed. By removing the second mask 34, the laminate of the first metal layer 15 and the second metal layer 16 and the side surface of the electrode 17 covered by the second mask 34 are exposed.

[0047] like Fig.13 As shown, in Fig.12 After removing the second mask 34, a third mask 35 containing resin is formed in a manner to cover a specific range of the laminate of the first metal layer 15 and the second metal layer 16 adjacent to the side of the electrode 17. The central area of ​​the laminate of the first metal layer 15 and the second metal layer 16 covering the protective layer 13 is not covered by the second mask 34 and is exposed.

[0048] like Fig.14 As shown, in Fig.13 After the third mask 35 is formed on the electrode 17 and the region adjacent to the electrode 17 , the central region of the laminate of the first metal layer 15 and the second metal layer 16 exposed from the third mask 35 is removed by etching using the second etching solution 36 .

[0049] In addition, the laminate of the first metal layer 15 and the second metal layer 16 covered by the third mask 35 at the end of the protective layer 13 is also removed by etching from the end of the third mask 35 to a specific depth using the second etching solution 36 that penetrates between the protective layer 13 and the third mask 35. Here, the protective layer 13 made of SiN has an affinity for the second etching solution 36 compared to the third mask 35 made of resin, and the etching of the laminate of the first metal layer 15 and the second metal layer 16 progresses faster as it is farther from the third mask 35 and closer to the protective layer 13. Therefore, the end surface of the laminate of the first metal layer 15 and the second metal layer 16 between the protective layer 13 and the third mask 35 is formed into an eave-like shape that protrudes forward as the height increases from the protective layer 13 toward the third mask 35.

[0050] Reference Figure 3 and Figure 4 , if in Fig.14 If the third mask 35 is removed from the Hall element 10, an island portion 20 formed by laminating the first metal layer 15 and the second metal layer 16 is formed just below the side surface of the electrode 17 on the surface of the protective layer 13 formed on the surface of the magnetically sensitive layer 12 in the Hall element 10. A portion of the root portion including the island portion 20 is located inward of the side surface of the electrode 17, and the remaining portion of the island portion 20 protrudes from the side surface of the electrode 17. The end surface 20b of the island portion 20 protruding from the side surface of the electrode 17 has an eaves-like shape that protrudes forward as the height from the surface of the protective layer 13 increases.

[0051] The island portion 20 is formed inside the electrode 17 and in contact with the main body on which the first metal layer 15 and the second metal layer 16 are stacked on the ohmic contact layer 14. Specifically, the root of the island portion 20 located inside the side surface of the electrode 17 is formed so as to face and contact the end of the stacked body of the ohmic contact layer 14, the first metal layer 15, and the second metal layer 16 formed on the surface of the protective layer 13. The end surface 14a of the ohmic contact layer 14 facing the root of the island portion 20 has an eaves-like shape that protrudes forward as the height from the surface of the protective layer 13 increases. The gap formed by the eaves-like end surface 14a of the ohmic contact layer 14, the end surface 20a of the root of the island portion 20, and the surface of the protective layer 13 is filled with gold plating constituting the electrode 17, thereby forming a metal filling portion 21.

[0052] The Hall element 10 can be manufactured by a series of steps as described above. In the manufacturing method of the Hall element, the island portion 20 formed by laminating the first metal layer 15 and the second metal layer 16 can be formed according to the usual manufacturing steps just below the side of the electrode 17 on the surface of the protective layer 13 formed on the surface of the magnetically sensitive layer 12, and the gold-plated metal filling portion 21 can be formed in the gap between the ohmic contact layer 14 and the island portion 20. The island portion 20 and the metal filling portion 21 formed in this way can reliably prevent moisture from penetrating from the interface between the protective layer 13 and the ohmic contact layer 14.

[0053] In addition, this embodiment is described by taking the Hall element 10 as an example, but is not limited to this. Not limited to the Hall element 10, as long as it is a semiconductor device that needs to prevent moisture from penetrating from the interface between the ohmic contact layer and the protective layer, it is possible to prevent moisture from penetrating by forming the island portion 20 and the metal filling portion 21 and sealing the interface in the same way as the Hall element 10. In a semiconductor device, instead of the magnetically sensitive layer 12 in the Hall element 10, it is generally possible to prevent the degradation of the active layer caused by the penetration of moisture by protecting the active layer from the penetration of moisture.

[0054] (Note 1)

[0055] The Hall element 10 includes: a substrate 11; a magnetically sensitive layer 12 disposed on a top surface 11a of the substrate 11; a protective layer 13 covering the magnetically sensitive layer 12 and having an opening 13a exposing a specific region of the magnetically sensitive layer 12; an ohmic contact layer 14 electrically connected to the magnetically sensitive layer 12 exposed from the opening 13a and having a portion thereof in contact with the protective layer 13 around the opening 13a; and a first metal layer 15 disposed on the ohmic contact layer 14 and having a portion thereof in contact with the protective layer 13 around the ohmic contact layer 14. Since the first metal layer 15 is in contact with the protective layer 13 around the ohmic contact layer 14, water can be prevented from penetrating from the interface between the ohmic contact layer 14 and the protective layer 13.

[0056] (Note 2)

[0057] According to the Hall element 10 described in Supplementary Note 1, the first metal layer 15 includes: a main body portion disposed on the ohmic contact layer 14; and an island portion 20 in contact with the protective layer 13 around the ohmic contact layer 14. The island portion 20 can prevent moisture from penetrating by sealing the interface between the ohmic contact layer 14 and the protective layer 13.

[0058] (Note 3)

[0059] According to the Hall element 10 described in Supplementary Note 2, it further includes an electrode 17 of the plated layer disposed on the first metal layer 15, forming a metal filling portion 21, which is formed by filling the metal of the plated layer in a gap 19 between the end surface 20a of the island portion 20 facing the ohmic contact layer 14 and the ohmic contact layer 14. The interface between the ohmic contact layer 14 and the protective layer 13 is further sealed by the metal filling portion 21, thereby preventing moisture from penetrating.

[0060] (Note 4)

[0061] According to the Hall element 10 described in Supplementary Note 3, the plated electrode 17 is continuously arranged from the main body of the first metal layer 15 to the island 20. The continuously formed plated electrode can fill the gap between the ohmic contact layer 14 and the island 20 with the plated metal.

[0062] (Note 5)

[0063] According to the Hall element 10 as described in any one of Supplementary Notes 1 to 4, the magnetically sensitive layer 12 includes a Group III-V compound semiconductor. For example, by using a semiconductor such as GaAs, the sensitivity of the Hall element 10 can be ensured.

[0064] (Note 6)

[0065] The Hall element 10 according to any one of Supplementary Notes 1 to 5, wherein the ohmic contact layer 14 is formed of an alloy that forms a eutectic body with the magnetic sensitive layer 12. By forming a eutectic body, a stable ohmic contact can be ensured.

[0066] (Note 7)

[0067] According to the Hall element 10 described in any one of Supplementary Notes 1 to 6, the first metal layer 15 is used to prevent the ohmic contact layer 14 from being balled, and the second metal layer 16 forming a base of the electrode 17 that becomes the plated layer is stacked. By preventing the alloy constituting the ohmic contact layer 14 from being balled, stable electrical conduction can be maintained, and by providing a base for the plated layer, stable growth of the plated layer can be ensured.

[0068] (Note 8)

[0069] The manufacturing method of the Hall element 10 comprises the following steps: forming a magnetically sensitive layer 12 on a top surface 11a of a substrate 11; forming a protective layer 13 covering the top surface 11a on which the magnetically sensitive layer 12 is formed so that a specific region of the magnetically sensitive layer 12 is exposed from an opening 13a; forming an ohmic contact layer 14, the ohmic contact layer 14 being electrically connected to the magnetically sensitive layer 12 exposed from the opening 13a and a portion thereof being in contact with the protective layer 13 around the opening; and forming a first metal layer 15, the first metal layer 15 being formed on the ohmic contact layer 14 and a portion thereof being in contact with the protective layer 13 around the ohmic contact layer 14. Since the first metal layer 15 is in contact with the protective layer 13 around the ohmic contact layer 14, water can be prevented from penetrating from the interface between the ohmic contact layer 14 and the protective layer 13.

[0070] (Note 9)

[0071] According to the manufacturing method of the Hall element 10 described in Supplementary Note 8, the step of forming the first metal layer 15 forms: a main body portion disposed on the ohmic contact layer 14, and an island portion 20 in contact with the protective layer 13 around the ohmic contact layer 14. The island portion 20 can prevent moisture from penetrating by sealing the interface between the ohmic contact layer 14 and the protective layer 13.

[0072] (Note 10)

[0073] According to the manufacturing method of the Hall element 10 described in Supplementary Note 9, it further includes a step of forming an electrode 17 of a plated layer on the first metal layer 15, and the step of forming the electrode 17 of the plated layer is to fill the metal of the plated layer in the gap 19 between the end surface 20a of the island portion 20 facing the ohmic contact layer 14 and the ohmic contact layer 14 to form a metal filling portion 21. The interface between the ohmic contact layer 14 and the protective layer 13 is further sealed by the metal filling portion 21, thereby preventing moisture from penetrating.

[0074] (Note 11)

[0075] According to the method for manufacturing the Hall element 10 described in Supplementary Note 10, the electrode 17 of the plated layer is continuously arranged from the main body of the first metal layer 15 to the island 20. The metal of the plated layer can be buried in the gap between the ohmic contact layer 14 and the island 20 by the continuously formed electrode of the plated layer.

[0076] (Note 12)

[0077] The semiconductor device includes: a substrate 11; an active layer disposed on a top surface 11a of the substrate 11; a protective layer 13 covering the active layer and having an opening 13a exposing a specific region of the active layer; an ohmic contact layer 14 electrically connected to the active layer exposed from the opening 13a and having a portion disposed on the protective layer 13 around the opening 13a; and a first metal layer 15 disposed on the ohmic contact layer 14 and having a portion in contact with the protective layer 13 around the ohmic contact layer 14. Since the first metal layer 15 is in contact with the protective layer 13 around the ohmic contact layer 14, water can be prevented from penetrating from the interface between the ohmic contact layer 14 and the protective layer 13.

[0078] Reference numerals

[0079] 10: Hall element

[0080] 11: Substrate

[0081] 12: Magnetic layer

[0082] 13: Protective layer

[0083] 13a: Opening

[0084] 14: Ohmic contact layer

[0085] 15: 1st metal layer

[0086] 16: 2nd metal layer

[0087] 17: Electrode

[0088] 20: Island

[0089] 21: Metal filling part.

Claims

1. A Hall element, comprising: substrate; A magnetically sensitive layer is disposed on the top surface of the substrate; a protective layer covering the magnetically sensitive layer and having an opening for exposing a specific area of ​​the magnetically sensitive layer; an ohmic contact layer, electrically connected to the magnetically sensitive layer exposed from the opening, and a portion of which is in contact with the protective layer around the opening; as well as The metal layer is disposed on the ohmic contact layer, and a portion of the metal layer is in contact with the protective layer around the ohmic contact layer.

2. The Hall element according to claim 1, wherein The metal layer has: A main body portion, disposed on the ohmic contact layer; and The island portion is in contact with the protective layer around the ohmic contact layer. 3 . The Hall element according to claim 2 , further comprising a plating layer disposed on the metal layer, wherein a metal of the plating layer is buried in a gap between an end surface of the island portion facing the ohmic contact layer and the ohmic contact layer. 4 . The Hall element according to claim 3 , wherein the plated layer is continuously arranged from the main body portion of the metal layer to the island portion. 5 . The Hall element according to claim 1 , wherein the magnetically sensitive layer includes a Group III-V compound semiconductor. 6 . The Hall element according to claim 1 , wherein the ohmic contact layer is formed of an alloy that forms a eutectic with the magnetically sensitive layer.

7. The Hall element according to any one of claims 1 to 6, wherein the metal layer is stacked with: a first metal layer, used to prevent the ohmic contact layer from balling up; and The second metal layer forms a base of the plated layer.

8. A method for manufacturing a Hall element, comprising the following steps: forming a magnetically sensitive layer on the top surface of the substrate; forming a protective layer covering the top surface on which the magnetically sensitive layer is formed in such a manner that a specific area of ​​the magnetically sensitive layer is exposed from the opening; forming an ohmic contact layer, the ohmic contact layer being electrically connected to the magnetically sensitive layer exposed from the opening and having a portion thereof being in contact with the protective layer around the opening; as well as A metal layer is formed on the ohmic contact layer, and a portion of the metal layer is in contact with the protective layer around the ohmic contact layer.

9. The method for manufacturing a Hall element according to claim 8, wherein The steps of forming the metal layer are as follows: A main body portion, disposed on the ohmic contact layer; and The island portion is in contact with the protective layer around the ohmic contact layer.

10. The manufacturing method of the Hall element according to claim 9 further comprises the step of forming a plating layer on the metal layer, wherein the step of forming the plating layer is to fill the metal of the plating layer in the gap between the side surface of the island portion opposite to the ohmic contact layer and the ohmic contact layer. 11 . The method for manufacturing a Hall element according to claim 10 , wherein the plated layer is continuously arranged from the main body portion of the metal layer to the island portion.

12. A semiconductor device comprising: substrate; An active layer, disposed on the top surface of the substrate; a protective layer covering the active layer and having an opening for exposing a specific region of the active layer; an ohmic contact layer electrically connected to the active layer exposed from the opening, and a portion of the ohmic contact layer is disposed on the protective layer around the opening; as well as The metal layer is disposed on the ohmic contact layer, and a portion of the metal layer is in contact with the protective layer around the ohmic contact layer.

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