Semiconductor device

Abstract

Provided is a semiconductor device capable of obtaining a more appropriate forward voltage of a body diode. The semiconductor device includes a first electrode, a first conductive portion, a semiconductor portion, a second conductive portion, a gate electrode, and an insulating portion. The direction from the first electrode to the first conductive portion is along the first direction. The semiconductor portion is of a first conductivity type including first and second semiconductor regions. At least a portion of the first semiconductor region is located between the first conductive portion and the first electrode. The first conductive portion is in Schottky contact with the first semiconductor region. A direction from the first conductive portion to the second semiconductor region is along a second direction intersecting the first direction. The second conductive portion is in Schottky contact with the second semiconductor region. At least a portion of the second conductive portion is located between the first conductive portion and the second semiconductor region. At least a portion of the second semiconductor region is located between the gate electrode and the second conductive portion. The insulating portion includes a first insulating region provided between the gate electrode and the second semiconductor region.

Description

Technical Field

[0001] Embodiments of the present invention relate to semiconductor devices. Background Art

[0002] There are semiconductor devices including a body diode.

[0003] Prior Art Documents

[0004] Patent Document 1: Japanese Patent No. 3417852 Summary of the Invention

[0005] Embodiments of the present invention provide a semiconductor device capable of obtaining a more appropriate forward voltage of a body diode.

[0006] According to an embodiment of the present invention, a semiconductor device includes a first electrode, a first conductive portion, a semiconductor portion, a second conductive portion, a gate electrode, and an insulating portion. The direction from the first electrode to the first conductive portion is along a first direction. The first conductive portion contains a metal, a metal oxide, or a metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru. The semiconductor portion is of a first conduction type including a first semiconductor region and a second semiconductor region. At least a part of the first semiconductor region is located between the first conductive portion and the first electrode. The first conductive portion is in Schottky contact with the first semiconductor region. The direction from the first conductive portion to the second semiconductor region is along a second direction crossing the first direction. The second conductive portion is in Schottky contact with the second semiconductor region. The second conductive portion contains at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co. At least a part of the second conductive portion is located between the first conductive portion and the second semiconductor region. At least a part of the second semiconductor region is located between the gate electrode and the second conductive portion. The insulating portion includes a first insulating region provided between the gate electrode and the second semiconductor region. Brief Description of the Drawings

[0007] Figure 1 is a schematic cross-sectional view illustrating a semiconductor device according to an embodiment.

[0008] Figure 2 is a schematic cross-sectional view illustrating a semiconductor device according to an embodiment.

[0009] Figure 3 of (a) and Figure 3 of (b) are schematic cross-sectional views illustrating a manufacturing method of a semiconductor device according to an embodiment.

[0010] Figure 4of (a) and Figure 4 (b) are schematic cross-sectional views of a method for manufacturing a semiconductor device according to an exemplary embodiment.

[0011] Figure 5 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0012] Figure 6 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0013] Figure 7 of (a) and Figure 7 of (b) are schematic cross-sectional views of a method for manufacturing a semiconductor device according to an exemplary embodiment.

[0014] Figure 8 of (a) and Figure 8 of (b) are schematic cross-sectional views of a method for manufacturing a semiconductor device according to an exemplary embodiment. DETAILED DESCRIPTION

[0015] Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings.

[0016] The accompanying drawings are schematic or conceptual diagrams, and the relationships between the thicknesses and widths of the respective parts, the ratios of the sizes between the parts, etc. are not necessarily the same as the actual structure. Even when representing the same part, the mutual dimensions and ratios may sometimes be shown differently depending on the accompanying drawings.

[0017] In the specification and the respective drawings of the present application, the same reference numerals are added to the same elements as those described with respect to the drawings that have already appeared, and the detailed description is appropriately omitted.

[0018] Figure 1 and Figure 2 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0019] In Figure 2 the periphery of the first conductive portion 21 in Figure 1 is enlarged and shown.

[0020] As Figure 1 shown, the semiconductor device 100 according to the embodiment includes a first electrode 11, a second electrode 20, a gate electrode 13, an insulating portion 40, and a semiconductor portion 30. The second electrode 20 includes at least a first conductive portion 21 and a second conductive portion 22. The second electrode 20 may further include a third conductive portion 23, a fourth conductive portion 24, a conductive layer 26, and a conductive layer 27.

[0021] The direction from the first electrode 11 to the first conductive portion 21 is along the first direction. In the description of the embodiment, the first direction is set as the Z direction. The direction intersecting the first direction is set as the second direction (X direction). The X direction can be a direction perpendicular to the Z direction. The direction intersecting the first direction and the second direction is set as the third direction (Y direction). The Y direction can be a direction perpendicular to the Z direction and the X direction. For example, the Z direction is a direction perpendicular to the upper surface 11a of the first electrode 11 that is in contact with the semiconductor portion 30. For example, the surface 30s (main surface of the semiconductor substrate) of the semiconductor portion 30 extends along the X-Y plane perpendicular to the Z direction. The surface 30s is the surface of the semiconductor portion 30 on the side of the second electrode 20 in the Z direction. In the Z direction, the positional relationship or direction from the first electrode 11 toward the second electrode 20 is sometimes referred to as up.

[0022] The direction from the first electrode 11 to the semiconductor portion 30 is along the first direction. The semiconductor portion 30 includes a first semiconductor region 31, a second semiconductor region 32, a third semiconductor region 33, a fourth semiconductor region 34, and a fifth semiconductor region 35. The semiconductor portion 30 (the first to fifth semiconductor regions) is of the first conductivity type. In addition, in this example, the first conductivity type is n-type and the second conductivity type is p-type, but in the embodiment, the first conductivity type can also be p-type and the second conductivity type can be n-type.

[0023] At least a part of the first semiconductor region 31 is located between the first conductive portion 21 and the first electrode 11. The direction from the first semiconductor region 31 to the first conductive portion 21 is along the Z direction.

[0024] At least a part of the second semiconductor region 32 is arranged with the first conductive portion 21 in the X direction. That is, the direction from the first conductive portion 21 to the second semiconductor region 32 is along the X direction. The second semiconductor region 32 can be away from the first conductive portion 21 in the X direction.

[0025] For example, a trench T1 is provided on the surface 30s of the semiconductor portion 30. The trench T1 is a recessed portion that is recessed downward (in the direction of the first electrode 11). The trench T1 extends, for example, in the Y direction. A plurality of trenches T1 can also be provided at intervals in the X direction. The first semiconductor region 31 forms the bottom surface of the trench T1. The second semiconductor region 32 forms the side surface of the trench T1.

[0026] The second semiconductor region 32 may also include a first region 32s and a second region 32c. The second region 32c is located between the first region 32s and the first electrode 11. The impurity concentration (atoms / cm 3 ) of the first conductivity type in the first region 32s is higher than the impurity concentration of the first conductivity type in the second region 32c.

[0027] The third semiconductor region 33 is located between the first electrode 11 and the first semiconductor region 31 in the Z direction. The fourth semiconductor region 34 is located between the first electrode 11 and the insulating portion 40 in the Z direction. The fifth semiconductor region 35 is located between the third semiconductor region 33 and the first electrode 11 in the Z direction and is arranged with the fourth semiconductor region 34 in the X direction. The fourth semiconductor region 34 and the fifth semiconductor region 35 are in contact with the first electrode 11. The semiconductor portion 30 is electrically connected to the first electrode 11 in the fourth semiconductor region 34 and the fifth semiconductor region 35.

[0028] The first conductive portion 21, the second conductive portion 22, and the third conductive portion 23 are provided in the trench T1. The second electrode 20 is electrically connected to the semiconductor portion 30 in the portion provided in the trench T1 (the first conductive portion 21, the second conductive portion 22, and the third conductive portion 23).

[0029] The first conductive portion 21 is in contact with the bottom of the trench T1. That is, the first conductive portion 21 is in contact with the first semiconductor region 31. The first conductive portion 21 is electrically connected to the first semiconductor region 31. The first conductive portion 21 is in Schottky contact with the first semiconductor region 31. The first conductive portion 21 may not be in contact with the side surface of the trench T1. That is, the first conductive portion 21 may not be in contact with the second semiconductor region 32 in the X direction. In this example, the first conductive portion 21 is a part of the conductive layer 25 (conductive film) included in the second electrode 20.

[0030] At least a part of the second conductive portion 22 is located between the first conductive portion 21 and the second semiconductor region 32. The position of the second conductive portion 22 in the X direction is between the position of the first conductive portion 21 in the X direction and the position of the second semiconductor region 32 in the X direction.

[0031] The second conductive portion 22 is in contact with the side surface of the trench T1 in the X direction. That is, the second conductive portion 22 is in contact with the second semiconductor region 32. The second conductive portion 22 is arranged with the second semiconductor region 32 in the X direction. In other words, the direction from the second conductive portion 22 to the second semiconductor region 32 (the first region 32s, the second region 32c) is along the X direction. The second conductive portion 22 is in Schottky contact with the second semiconductor region 32 (the second region 32c). In addition, the second conductive portion 22 is in contact with the first conductive portion 21 in the X direction and is electrically connected to the first conductive portion 21.

[0032] The second conductive portion 22 is provided on a part of the first semiconductor region 31. That is, this part of the first semiconductor region 31 is located between the second conductive portion 22 and the first electrode 11. The second conductive portion 22 is in contact with the bottom of the trench T1. That is, the second conductive portion 22 is in contact with this part of the first semiconductor region 31. For example, the second conductive portion 22 is in Schottky contact with this part of the first semiconductor region 31.

[0033] The third conductive portion 23 is located above the second conductive portion 22. That is, the second conductive portion 22 is located between the third conductive portion 23 and the first semiconductor region 31 in the Z direction. The direction from the second conductive portion 22 to the third conductive portion 23 is along the Z direction. The upper end of the third conductive portion 23 is in contact with the second conductive portion 22. The third conductive portion 23 is electrically connected to the second conductive portion 22.

[0034] The third conductive portion 23 is in contact with the side surface of the trench T1. That is, the third conductive portion 23 is in contact with the second semiconductor region 32. The third conductive portion 23 and the second semiconductor region 32 are arranged in the X direction. In other words, the direction from the third conductive portion 23 to the second semiconductor region 32 (the first region 32s) is along the X direction.

[0035] In this example, the third conductive portion 23 is a part of the conductive layer 25. For example, the first conductive portion 21 and the third conductive portion 23 are formed of substantially the same material and are included in a continuous conductive layer 25.

[0036] The direction from the second conductive portion 22 to the gate electrode 13 is along the X direction. At least a part of the second semiconductor region 32 is located between the gate electrode 13 and the second conductive portion 22.

[0037] As Figure 1 shown, the semiconductor device 100 further includes a conductive portion 14 (conductive region). The direction from the conductive portion 14 to the third semiconductor region 33 is along the X direction. In this example, the direction from the conductive portion 14 to the gate electrode 13 is along the Z direction. The conductive portion 14 is provided between the gate electrode 13 and the first electrode 11. A fourth semiconductor region 34 is provided between the conductive portion 14 and the first electrode 11.

[0038] The insulating portion 40 is in contact with the gate electrode 13, the conductive portion 14, and the semiconductor portion 30. The insulating portion 40 electrically insulates the gate electrode 13 and the semiconductor portion 30. The insulating portion 40 electrically insulates the conductive portion 14 and the semiconductor portion 30. The insulating portion 40 electrically insulates the gate electrode 13 and the conductive portion 14.

[0039] More specifically, the insulating portion 40 includes a first insulating region 41 provided between the second semiconductor region 32 and the gate electrode 13. In addition, the insulating portion 40 includes a third insulating region 43 provided between the third semiconductor region 33 and the conductive portion 14. Moreover, the insulating portion 40 includes a portion provided between the fourth semiconductor region 34 and the conductive portion 14, a portion provided between the conductive portion 14 and the gate electrode 13, and a portion provided between the gate electrode 13 and the conductive layer 25.

[0040] For example, as Figure 1As shown, a trench T2 is provided on the surface 30s of the semiconductor portion 30. The trench T2 is a recessed portion that is recessed downward. The trench T2 extends, for example, in the Y direction. A plurality of trenches T2 may be provided at intervals in the X direction. In the X direction, trenches T1 and trenches T2 are alternately arranged. At least a part of the insulating portion 40 is provided in the trench T2. The gate electrode 13 and the conductive portion 14 are surrounded by the insulating portion 40 in the trench T2.

[0041] The insulating portion 40 has an end face 40s (upper surface) in the Z direction. The gate electrode 13 is located between the end face 40s and the first electrode 11. In this example, the end face 40s of the insulating portion 40 is located above the semiconductor portion 30. In other words, the position of the semiconductor portion 30 in the Z direction is between the position of the end face 40s of the insulating portion 40 in the Z direction and the position of the first electrode 11 in the Z direction.

[0042] The conductive layer 25 is provided above the insulating portion 40, the semiconductor portion 30, and the second conductive portion 22. In other words, the insulating portion 40, the semiconductor portion 30, and the second conductive portion 22 are located between the conductive layer 25 and the first electrode 11. The conductive layer 25 is in contact with the semiconductor portion 30 and the second conductive portion 22 and is electrically connected to the semiconductor portion 30 and the second conductive portion 22. The conductive layer 25 is in contact with the end face 40s of the insulating portion 40.

[0043] The conductive layer 26 is laminated on the conductive layer 25. In other words, the conductive layer 25 is located between the conductive layer 26 and the first electrode 11. The conductive layer 26 is in contact with the conductive layer 25 and is electrically connected to the conductive layer 25. A part of the conductive layer 26 is disposed in the trench T1. Another part of the conductive layer 26 is disposed above the insulating portion 40. That is, the direction from the insulating portion 40 to the other part of the conductive layer 26 is along the Z direction.

[0044] The conductive layer 27 is laminated on the conductive layer 26. In other words, the conductive layer 26 is located between the conductive layer 27 and the first electrode 11. The conductive layer 27 is in contact with the conductive layer 26 and is electrically connected to the conductive layer 26.

[0045] The semiconductor device 100 is, for example, a MOSFET (Metal Oxide Silicon Field Effect Transistor). By controlling the potential of the gate electrode 13, the current flowing between the first electrode 11 and the second electrode 20 can be controlled. The first electrode 11 functions as a drain electrode, for example. The second electrode 20 functions as a source electrode, for example. The first region 32s of the second semiconductor region 32 functions as a source region, for example. The second region 32c of the second semiconductor region 32 functions as a channel region, for example. The first insulating region 41 functions as a gate insulating film, for example.

[0046] For example, a Schottky barrier is formed at the interface between the second conductive portion 22 and the second semiconductor region 32 (second region 32c), and a depletion layer is formed in the second semiconductor region 32 (second region 32c). The potential of the gate electrode 13 is used to control the thickness (distance in the X direction) of the Schottky barrier, and the carrier concentration in the second semiconductor region 32 (second region 32c) is controlled. When the carrier concentration in the second semiconductor region 32 is low, substantially no current flows between the second electrode 20 and the first electrode 11 via the second semiconductor region 32. That is, an off state is obtained. By controlling the potential of the gate electrode 13, when the carrier concentration in the second semiconductor region 32 becomes high, current flows between the second electrode 20 and the first electrode 11 via the second semiconductor region 32. That is, an on state is obtained. For example, carriers flow between the second electrode 20 and the semiconductor portion 30 via a portion of the second electrode 20 that is in contact with the first region 32s (a part of the second conductive portion 22, the third conductive portion 23, and the fourth conductive portion 24).

[0047] In addition, for example, a Schottky barrier is formed at the interface between the first conductive portion 21 (and the second conductive portion 22) and the first semiconductor region 31. The potential of the gate electrode 13 can be used to control the thickness (distance in the Z direction) of the Schottky barrier. When the Schottky barrier is thick, it is difficult for current to flow. For example, an off state is obtained. By controlling the potential of the gate electrode 13, the Schottky barrier becomes thinner, and it is easy for a tunnel current to flow. For example, an on state is obtained.

[0048] For example, the conductive portion 14 is electrically connected to the second electrode 20. Alternatively, the conductive portion 14 may be capable of being electrically connected to the second electrode 20. For example, as Figure 1 shown, the semiconductor device 100 may also have a wiring 14L that electrically connects the conductive portion 14 and the second electrode 20. The conductive portion 14 and the second electrode 20 may also be electrically connected via wirings and terminals outside the semiconductor device 100.

[0049] The potential of the conductive portion 14 is set to the potential of the second electrode 20 (for example, the source potential). By providing the conductive portion 14, the electric field in the semiconductor portion 30 can be controlled. For example, local electric field concentration can be suppressed. For example, it is easy to obtain high reliability. The conductive portion 14 functions as a field plate, for example.

[0050] For example, there is a transistor in a reference example having an npn structure. In this case, the gate length becomes longer according to the width of the pn junction. In contrast, in the embodiment, the semiconductor portion 30 is of the first conductivity type and may not include a region of the second conductivity type. That is, a pn junction is not formed. Thus, for example, it is easy to shorten the gate length. Therefore, it is easy to reduce the gate capacitance. In addition, for example, it is easy to reduce the on-resistance. It is possible to achieve high-speed switching, suppression of turn-on loss, and suppression of turn-off loss. According to the embodiment, a semiconductor device capable of improving characteristics can be provided.

[0051] In the transistor of the reference example, a body diode is formed of a pn structure. Therefore, the recovery sometimes requires a long time. In contrast, in the embodiment, a Schottky barrier is formed at the interface between the first conductive portion 21 and the first semiconductor region 31. Thus, a body diode is formed. In this way, since the body diode is a Schottky barrier diode, the recovery characteristics can be improved. The recovery can be made high-speed. The forward voltage of the body diode can be reduced.

[0052] The first conductive portion 21 is, for example, a metal or a metal oxide or a metal nitride containing at least one element selected from the group consisting of Ti (titanium), Ta (tantalum), W (tungsten), Cr (chromium), and Ru (ruthenium). The first conductive portion 21 contains, for example, a material with a relatively small work function.

[0053] That is, the first conductive portion 21 contains a first element. The first element is, for example, at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru. The first conductive portion 21 contains, for example, a monomer metal composed of the first element (such as Ti, Ta, W, Cr, Ru, etc.). The first conductive portion 21 may also contain, for example, a compound containing the first element. For example, the first conductive portion 21 contains a nitride of the first element (such as titanium nitride, tantalum nitride, tungsten nitride, chromium nitride, ruthenium nitride, etc.). For example, the first conductive portion 21 contains an oxide of the first element (such as titanium oxide, tantalum oxide, tungsten oxide, chromium oxide, ruthenium oxide, etc.). Alternatively, the first conductive portion 21 may also contain an alloy containing the first element or a solid solution containing the first element.

[0054] The second conductive portion 22 contains, for example, at least one element selected from the group consisting of Pt (platinum), Ni (nickel), Ir (iridium), Pd (palladium), Au (gold), and Co (cobalt). The first conductive portion 21 contains, for example, a material with a relatively large work function.

[0055] That is, the second conductive portion 22 contains a second element. The second element is, for example, at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co. The second conductive portion 22 contains, for example, a monomer metal composed of the second element (such as Pt, Ni, Ir, Pd, Au, Co, etc.). The second conductive portion 22 may also contain, for example, a compound, an alloy, or a solid solution containing the second element.

[0056] The first conductive portion 21, the material of which is different from that of the second conductive portion 22 described above, contacts the first semiconductor region 31. Thereby, the height of the Schottky barrier between the first conductive portion 21 and the semiconductor portion 30 can be controlled, and the forward voltage of the body diode can be controlled. According to the embodiment, a more appropriate forward voltage of the body diode can be obtained.

[0057] In this example (the first conduction type is n-type), the work function of the first conductive portion 21 may be lower than the work function of the second conductive portion 22. For example, the first conductive portion 21 is composed of a first conductive material having a work function lower than that of the second conductive portion 22 (the second conductive material). For example, the second conductive portion 22 is composed of a second conductive material having a work function higher than that of the first conductive portion 21 (the first conductive material). In this example, the first conductive portion 21 having a work function lower than that of the second conductive portion 22 contacts the bottom of the trench T1, thereby obtaining, for example, a low forward voltage of the body diode.

[0058] The second conductive portion 22 contacts the second semiconductor region 32. Thereby, the height of the Schottky barrier between the second semiconductor region 32 and the second conductive portion 22 can be controlled, and the threshold value of the transistor can be controlled. In this example (the first conduction type is n-type), the second conductive portion 22 having a work function higher than that of the first conductive portion 21 contacts the side surface of the trench T1, thereby, for example, being able to prevent the threshold value from becoming too low.

[0059] The third conductive portion 23 is, for example, a metal, a metal oxide, or a metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru. The third conductive portion 23 contains, for example, a material having a relatively small work function.

[0060] That is, the third conductive portion 23 contains a third element. The third element is, for example, at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru. The third conductive portion 23 contains, for example, a monomer metal composed of the third element (such as Ti, Ta, W, Cr, Ru, etc.). Alternatively, the third conductive portion 23 may, for example, also contain a compound containing the third element. For example, the third conductive portion 23 contains a nitride of the third element (such as titanium nitride, tantalum nitride, tungsten nitride, chromium nitride, ruthenium nitride, etc.). In addition, for example, the third conductive portion 23 contains an oxide of the third element (such as titanium oxide, tantalum oxide, tungsten oxide, chromium oxide, ruthenium oxide, etc.). Alternatively, the third conductive portion 23 may also contain an alloy containing the third element or a solid solution containing the third element.

[0061] The third conductive portion 23 is connected above the second conductive portion 22. And the third conductive portion 23, which is made of a material different from that of the second conductive portion 22 as described above, contacts the second semiconductor region 32. The contact resistance between the second electrode 20 and the semiconductor portion 30 can be controlled by using the third conductive portion 23.

[0062] In this example (where the first conduction type is n-type), the work function of the third conductive portion 23 may be lower than the work function of the second conductive portion 22. For example, the third conductive portion 23 is made of a third conductive material whose work function is lower than the work function of the second conductive portion 22. For example, the third conductive portion 23 is made of the same material as that of the first conductive portion 21. The work function of the third conductive portion 23 may be the same as the work function of the first conductive portion 21. In this example, the third conductive portion 23, whose work function is lower than that of the second conductive portion 22, contacts the second semiconductor region 32 (the first region 32s), thereby, for example, reducing the contact resistance.

[0063] The material of the conductive layer 25 may be the same as the material of the first conductive portion 21 or the material of the third conductive portion 23.

[0064] The fourth conductive portion 24 is provided above the second semiconductor region 32. That is, the second semiconductor region 32 is located between the fourth conductive portion 24 and the first electrode 11. The direction from the second semiconductor region 32 to the fourth conductive portion 24 is along the Z direction. The fourth conductive portion 24 is in contact with the second semiconductor region 32 (the first region 32s). The fourth conductive portion 24 may also be electrically connected to the second semiconductor region 32 (the first region 32s). The fourth conductive portion 24 is located between the insulating portion 40 and the conductive layer 25 and is in contact with the insulating portion 40 and the conductive layer 25. The fourth conductive portion 24 may also be electrically connected to the conductive layer 25.

[0065] The fourth conductive portion 24 contains, for example, at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co. The fourth conductive portion 24 contains, for example, a material with a relatively large work function.

[0066] That is, the fourth conductive portion 24 contains a fourth element. The fourth element is, for example, at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co. The fourth conductive portion 24, for example, contains a monomer metal (such as Pt, Ni, Ir, Pd, Au, Co, etc.) composed of the fourth element. The fourth conductive portion 24 may also contain, for example, a compound, an alloy, or a solid solution containing the fourth element.

[0067] In this example (where the first conduction type is n-type), the work function of the fourth conductive portion 24 may also be higher than the work function of the first conductive portion 21. For example, the fourth conductive portion 24 is composed of a fourth conductive material having a work function higher than the work function of the first conductive portion 21. For example, the fourth conductive portion 24 is composed of the same material as the material of the second conductive portion 22. The work function of the fourth conductive portion 24 may be the same as the work function of the second conductive portion 22.

[0068] As Figure 2 shown, the first conductive portion 21 has an end portion 21u (lower end). In addition, the second conductive portion 22 has a first end portion 22t (upper end) as an end portion in the Z direction and a first other end portion 22u (lower end). The first other end portion 22u (lower end) is arranged in the X direction with the end portion 21u. At least a part of the first other end portion 22u is located between the first end portion 22t and the first electrode 11.

[0069] The first semiconductor region 31 has a facing surface F1 facing the first conductive portion 21 and the second conductive portion 22. The facing surface F1 is located at the bottom of the trench T1 and, for example, is along the X-Y plane. The facing surface F1 is in contact with the lower ends (end portion 21u and the first other end portion 22u) of the first conductive portion 21 and the second conductive portion 22. The direction from the facing surface F1 to the gate electrode 13 is along the X direction.

[0070] The gate electrode 13 has a gate end portion 13t (upper end) as an end portion in the Z direction and a gate other end portion 13u (lower end). The gate other end portion 13u is located between the gate end portion 13t and the first electrode 11. The gate other end portion 13u (lower end) may also be located below the facing surface F1. That is, the position of the facing surface F1 in the Z direction may also be between the position of the gate end portion 13t in the Z direction and the position of the gate other end portion 13u in the Z direction. Thereby, for example, it is easy to control the width of the depletion layer by the gate electrode 13.

[0071] For example, the length L1 in the Z direction of the second conductive portion 22 that is in contact with the second semiconductor region 32 is longer than the length L2 in the Z direction of the third conductive portion 23 that is in contact with the second semiconductor region 32. For example, the position of the gate end portion 13t (upper end) in the Z direction is between the position of the first end portion 22t of the second conductive portion 22 in the Z direction and the position of the first other end portion 22u in the Z direction. In this way, the second conductive portion 22 is provided with a margin that overlaps with the gate electrode 13 and the second semiconductor region 32 (second region 32c) in the X direction. Considering the process margin, it is easy to deplete the channel region of the second semiconductor region 32.

[0072] As Figure 2 shown, for example, the length L3 can also be longer than the length L2. The length L3 is the length in the Z direction between the gate end portion 13t and the first end portion 22t. Alternatively, the length L2 can also be longer than the length L3. In the case where the length L2 is long, for example, it is easy to reduce the contact resistance.

[0073] For example, the length L4 in the X direction of the second conductive portion 22 that is in contact with the first semiconductor region 31 (for example, the width of the second conductive portion 22 in the X direction) can also be longer than the length L5 in the X direction of the first conductive portion 21 that is in contact with the first semiconductor region 31. In the case where the length L4 is long, for example, the depletion layer is easy to expand in the semiconductor portion 30. For example, the breakdown voltage can be increased. In addition, the length L5 can also be longer than the length L4.

[0074] The semiconductor portion 30 may include at least one element selected from the group consisting of silicon (Si), nitride semiconductors (such as GaN, etc.), silicon carbide (SiC), and oxide semiconductors (such as GaO). The semiconductor portion 30 is, for example, a silicon substrate. In the case where the semiconductor portion 30 contains silicon, the n-type impurities, for example, contain at least one element selected from the group consisting of phosphorus, arsenic, and antimony. The p-type impurities, for example, contain boron.

[0075] The first electrode 11, for example, contains at least one element selected from the group consisting of Al, Cu, Mo, W, Ta, Co, Ru, Ti, and Pt. The gate electrode 13 and the conductive portion 14, for example, may contain at least any one of polysilicon and metal. The conductive layer 26, for example, contains at least one selected from the group consisting of Ti and TiN. The conductive layer 27, for example, contains at least one element selected from the group consisting of Al, Cu, Mo, W, Ta, Co, Ru, Ti, and Pt.

[0076] A plurality of the first semiconductor regions 31, the second semiconductor regions 32, the first conductive portions 21, the second conductive portions 22, the third conductive portions 23, and the fourth conductive portions 24 may also be provided. A plurality of trenches T1 arranged in the X direction are provided, and the first conductive portion 21, the second conductive portion 22, and the third conductive portion 23 are provided in each trench T1. The plurality of first conductive portions 21, the plurality of second conductive portions 22, and the plurality of third conductive portions 23 are included in one conductive layer 25.

[0077] A plurality of gate electrodes 13, conductive portions 14, and insulating portions 40 may also be provided. A plurality of trenches T2 arranged in the X direction are provided, and the gate electrode 13, the conductive portion 14, and the insulating portion 40 are provided in each trench T2. One trench T1 is provided between two trenches T2. In one trench T1, one first conductive portion 21, two second conductive portions 22, and two third conductive portions 23 are arranged.

[0078] That is, as Figure 1 shown, at least a part of one second semiconductor region 32 and at least a part of another second semiconductor region 32 (semiconductor region 32b) are located between one gate electrode 13 and another gate electrode 13 (gate electrode 13b). The side surfaces of one second semiconductor region 32 and the side surfaces of another second semiconductor region 32 are two side surfaces of the trench T1 facing each other.

[0079] One second conductive portion 22 and another second conductive portion 22 (conductive portion 22b) are located between one second semiconductor region 32 and another second semiconductor region 32. In addition, one third conductive portion 23 and another third conductive portion 23 (conductive portion 23b) are located between one second semiconductor region 32 and another second semiconductor region 32. One second conductive portion 22 and one third conductive portion 23 are in contact with the side surface of one second semiconductor region 32. Another second conductive portion 22 and another third conductive portion 23 are in contact with the side surface of another second semiconductor region 32.

[0080] One first conductive portion 21 is arranged between one second conductive portion 22 and another second conductive portion 22. One first conductive portion 21 is in contact with one second conductive portion 22 and another second conductive portion 22. One first conductive portion 21, one second conductive portion 22, and another second conductive portion 22 are in contact with the bottom of one trench T1 (one first semiconductor region 31).

[0081] One fourth conductive portion 24 is provided above one second semiconductor region 32, and another fourth conductive portion (conductive portion 24b) is provided above another second semiconductor region 32.

[0082] Figure 3 of (a), Figure 3 of (b), Figure 4of (a) and Figure 4 (b) are schematic cross-sectional views of a method for manufacturing a semiconductor device according to an exemplary embodiment. These illustrate a part of the manufacturing process of the semiconductor device 100.

[0083] As Figure 3 shown in (a), a trench T2 is formed on the surface 30s of the semiconductor portion 30. An insulating portion 40, a conductive portion 14, and a gate electrode 13 are buried in the trench T2. In addition, a trench T1 is formed on the surface 30s of the semiconductor portion 30. Thereby, a first semiconductor region 31 and a second semiconductor region 32 are formed.

[0084] As Figure 3 shown in (b), a conductive film 22f that becomes the second conductive portion 22 and the fourth conductive portion 24 is formed over the semiconductor portion 30 and the insulating portion 40. The conductive film 22f is in contact with the end face 40s of the insulating portion 40, the side surfaces and upper ends of the second semiconductor region 32, and the first semiconductor region 31.

[0085] As Figure 4 shown in (a), for example, a part of the conductive film 22f is removed by reactive ion etching. Thereby, the second conductive portion 22 and the fourth conductive portion 24 are formed, and the end face 40s of the insulating portion 40, the side surface of the first region 32s of the second semiconductor region 32, and a part of the first semiconductor region 31 are exposed.

[0086] As Figure 4 shown in (b), a continuous conductive layer 25 is formed over the first semiconductor region 31, the second conductive portion 22, the fourth conductive portion 24, and the insulating portion 40. The conductive layer 25 is in contact with the first semiconductor region 31 and the second semiconductor region 32 (the first region 32s) exposed in Figure 4 (a). Thereby, the first conductive portion 21 and the third conductive portion 23 are formed. The conductive layer 25 covers the end face 40s of the insulating portion 40 and is in contact with the end face 40s.

[0087] In this way, the first conductive portion 21 and the third conductive portion 23 are included in the conductive layer 25 that covers the second conductive portion 22, the fourth conductive portion 24, and the insulating portion 40. By forming the conductive layer 25 so as to cover the second conductive portion 22, the first conductive portion 21 and the third conductive portion 23 can be formed.

[0088] Figure 5 and Figure 6 are schematic cross-sectional views of a semiconductor device according to an exemplary embodiment.

[0089] In Figure 6 , the periphery of the first conductive portion 21 in Figure 5 is enlarged and shown.

[0090] In Figure 5 and Figure 6 In the semiconductor device 101 shown, the fourth conductive portion 24 is not provided over the second semiconductor region 32, and the insulating portion 40 includes a second insulating region 42.

[0091] The second insulating region 42 is located over the second semiconductor region 32. In other words, the second semiconductor region 32 is located between the second insulating region 42 and the first electrode 11. The direction from the second semiconductor region 32 toward the second insulating region 42 is along the Z direction.

[0092] For example, as Figure 6 shown, the second semiconductor region 32 has an upper surface 32f (upper end). The upper surface 32f faces, for example, the Z direction and extends along the X - Y plane. The second insulating region 42 is in contact with the upper surface 32f of the second semiconductor region 32. The entire upper surface 32f may be covered by the second insulating region 42. The upper surface 32f may not be in contact with the second electrode 20. A part of the conductive layer 25 is provided on the second insulating region 42 and is in contact with the second insulating region 42.

[0093] Regarding other than the above, in Figure 5 and Figure 6 In the structure of the semiconductor device 101 shown, the same description as that of the above - mentioned semiconductor device 100 can be applied. In the semiconductor device 101, a more appropriate forward voltage of the body diode can also be obtained in the same manner as in the semiconductor device 100. For example, the forward voltage can be reduced. In addition, the contact resistance between the second electrode 20 and the semiconductor portion 30 can be reduced.

[0094] As Figure 1 in the semiconductor device 100 shown, etc., when the fourth conductive portion 24 in contact with the upper surface of the second semiconductor region 32 is provided, a path through which carriers flow between the fourth conductive portion 24 and the semiconductor portion 30 is formed via the upper surface of the second semiconductor region 32. At this time, for example, a contact resistance is generated between the upper surface of the second semiconductor region 32 and the fourth conductive portion 24. For example, the fourth conductive portion 24 has a high work function and a high contact resistance is generated. On the other hand, in Figure 5 in the semiconductor device 101 shown, etc., the second insulating region 42 is provided, and the contact between the upper surface 32f of the second semiconductor region 32 and the second electrode 20 is suppressed. The flow of carriers via the upper surface 32f of the second semiconductor region 32 is suppressed, and the contact is easily adjusted. For example, the contact resistance can be reduced.

[0095] Figure 7 of (a), Figure 7 of (b), Figure 8 of (a) and Figure 8(b) is a schematic cross-sectional view of a method for manufacturing a semiconductor device according to an exemplary embodiment. In these figures, a part of the manufacturing process of the semiconductor device 101 is illustrated.

[0096] As Figure 7 shown in (a) of, a trench T2 is formed on the surface 30s of the semiconductor portion 30. Inside the trench T2, an insulating portion 40, a conductive portion 14, and a gate electrode 13 are buried. A part of the insulating portion 40 (the part that becomes the second insulating region 42) is disposed on a part of the semiconductor portion 30 (the part that becomes the second semiconductor region 32). In addition, a trench T1 is formed on the surface 30s of the semiconductor portion 30. Thereby, a first semiconductor region 31 and a second semiconductor region 32 are formed. In addition, a second insulating region 42 located above the second semiconductor region 32 is formed.

[0097] As Figure 7 shown in (b) of, a conductive film 22f that becomes the second conductive portion 22 and the fourth conductive portion 24 is formed on the semiconductor portion 30 and the insulating portion 40. The conductive film 22f is in contact with the end face 40s of the insulating portion 40, the second insulating region 42, the side surfaces of the second semiconductor region 32, and the first semiconductor region 31.

[0098] As Figure 8 shown in (a) of, for example, a part of the conductive film 22f is removed by reactive ion etching. Thereby, the second conductive portion 22 is formed, and the end face 40s of the insulating portion 40, the second insulating region 42, the side surfaces of the first region 32s of the second semiconductor region 32, and a part of the first semiconductor region 31 are exposed.

[0099] As Figure 8 shown in (b) of, a continuous conductive layer 25 is formed on the first semiconductor region 31, the second conductive portion 22, and the insulating portion 40. The conductive layer 25 is in contact with the first semiconductor region 31 and the second semiconductor region 32 (the first region 32s) exposed in Figure 8 (a) of. Thereby, the first conductive portion 21 and the third conductive portion 23 are formed. The conductive layer 25 covers the end face 40s of the insulating portion 40 and the second insulating region 42, and is in contact with the end face 40s and the second insulating region 42.

[0100] In this way, the first conductive portion 21 and the third conductive portion 23 are included in the conductive layer 25 that covers the second conductive portion 22 and the second insulating region 42. By forming the conductive layer 25 so as to cover the second conductive portion 22, the first conductive portion 21 and the third conductive portion 23 can be formed.

[0101] The embodiment may also include the following structures (for example, technical solutions).

[0102] (Structure 1)

[0103] A semiconductor device includes:

[0104] A first electrode;

[0105] A first conductive portion extending in a first direction from the first electrode towards the first conductive portion, the first conductive portion including a metal, metal oxide, or metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru;

[0106] A semiconductor portion of a first conductivity type including a first semiconductor region and a second semiconductor region, at least a part of the first semiconductor region being located between the first conductive portion and the first electrode, the first conductive portion being in Schottky contact with the first semiconductor region, and extending in a second direction intersecting the first direction from the first conductive portion towards the second semiconductor region;

[0107] A second conductive portion in Schottky contact with the second semiconductor region, the second conductive portion including at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co, and at least a part of the second conductive portion being located between the first conductive portion and the second semiconductor region;

[0108] A gate electrode, at least a part of the second semiconductor region being located between the gate electrode and the second conductive portion; and

[0109] An insulating portion including a first insulating region provided between the gate electrode and the second semiconductor region.

[0110] (Structure 2)

[0111] The semiconductor device according to Structure 1, wherein

[0112] The semiconductor device further includes a third conductive portion connected to the second semiconductor region, the third conductive portion including a metal, metal oxide, or metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru,

[0113] The second conductive portion is located between the third conductive portion and the first semiconductor region.

[0114] (Structure 3)

[0115] The semiconductor device according to Structure 2, wherein

[0116] The second semiconductor region includes a first region and a second region located between the first region and the first electrode,

[0117] The concentration of impurities of the first conductivity type in the first region is higher than the concentration of impurities of the first conductivity type in the second region.

[0118] The third conductive portion is in contact with the first region.

[0119] (Structure 4)

[0120] The semiconductor device according to Structure 2 or 3, wherein

[0121] The length of the second conductive portion in contact with the second semiconductor region along the first direction is longer than the length of the third conductive portion in contact with the second semiconductor region along the first direction.

[0122] (Structure 5)

[0123] The semiconductor device according to Structure 4, wherein

[0124] The second conductive portion includes a first end portion and a first other end portion.

[0125] The first other end portion is located between the first end portion and the first electrode in the first direction.

[0126] The gate electrode includes a gate end portion and a gate other end portion.

[0127] The gate other end portion is located between the gate end portion and the first electrode in the first direction.

[0128] The position of the gate end portion in the first direction is between the position of the first end portion in the first direction and the position of the first other end portion in the first direction.

[0129] (Structure 6)

[0130] The semiconductor device according to any one of Structures 2 to 5, wherein

[0131] The first conductive portion and the third conductive portion are included in a conductive layer covering the second conductive portion.

[0132] (Structure 7)

[0133] The semiconductor device according to Structure 6, wherein

[0134] The conductive layer is in contact with the end face of the insulating portion in the first direction.

[0135] (Structure 8)

[0136] The semiconductor device according to any one of Structures 1 to 5, wherein

[0137] The semiconductor device further includes a fourth conductive portion containing at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co.

[0138] The second semiconductor region is located between the fourth conductive portion and the first electrode and is in contact with the fourth conductive portion.

[0139] (Structure 9)

[0140] The semiconductor device according to Structure 8, wherein

[0141] The first conductive portion is included in a conductive layer covering the second conductive portion and the fourth conductive portion.

[0142] (Structure 10)

[0143] The semiconductor device according to any one of Structures 1 to 5, wherein

[0144] The insulating portion further includes a second insulating region.

[0145] The second semiconductor region is located between the second insulating region and the first electrode and is in contact with the second insulating region.

[0146] (Structure 11)

[0147] The semiconductor device according to Structure 10, wherein

[0148] The first conductive portion is included in a conductive layer covering the second conductive portion and the second insulating region.

[0149] (Structure 12)

[0150] The semiconductor device according to any one of Structures 1 to 11, wherein

[0151] The work function of the first conductive portion is lower than the work function of the second conductive portion.

[0152] (Structure 13)

[0153] The semiconductor device according to any one of Structures 2 to 7, wherein

[0154] The work function of the third conductive portion is lower than the work function of the second conductive portion.

[0155] (Structure 14)

[0156] The semiconductor device according to Structure 8 or 9, wherein

[0157] The work function of the fourth conductive portion is higher than the work function of the first conductive portion.

[0158] (Structure 15)

[0159] The semiconductor device according to any one of Structures 1 to 14, wherein

[0160] A part of the first semiconductor region is located between the second conductive portion and the first electrode,

[0161] The second conductive portion is in contact with the part of the first semiconductor region.

[0162] (Structure 16)

[0163] The semiconductor device according to Structure 15, wherein

[0164] The length of the second conductive portion in the second direction in contact with the first semiconductor region is longer than the length of the first conductive portion in the second direction in contact with the first semiconductor region.

[0165] (Structure 17)

[0166] The semiconductor device according to any one of Structures 1 to 16, wherein

[0167] The semiconductor device further includes a conductive region,

[0168] The semiconductor portion includes a third semiconductor region located between the first semiconductor region and the first electrode,

[0169] The direction from the conductive region toward the third semiconductor region is along the second direction,

[0170] The insulating portion includes a third insulating region provided between the third semiconductor region and the conductive region.

[0171] (Structure 18)

[0172] The semiconductor device according to any one of Structures 1 to 17, wherein

[0173] The first semiconductor region has a facing surface facing the first conductive portion,

[0174] The direction from the facing surface to the gate electrode is along the second direction.

[0175] (Structure 19)

[0176] The semiconductor device according to any one of Structures 1 to 18, wherein

[0177] A plurality of the gate electrodes, the second semiconductor regions, and the second conductive portions are respectively provided,

[0178] At least a part of one of the second semiconductor regions and at least a part of the other second semiconductor region are located between one of the gate electrodes and the other gate electrode.

[0179] One of the second conductive parts and the other second conductive part are located between one of the second semiconductor regions and the other second semiconductor region.

[0180] The first conductive part is located between one of the second conductive parts and the other second conductive part.

[0181] In an embodiment, information related to the shape and the like of the semiconductor region is obtained, for example, by observation with an electron microscope or the like. For example, information related to the material and the impurity concentration in the semiconductor region is obtained by EDX (Energy Dispersive X-ray Spectroscopy) or SIMS (Secondary Ion Mass Spectrometry) or the like.

[0182] According to an embodiment, a semiconductor device capable of obtaining a more appropriate forward voltage of a body diode can be provided.

[0183] In addition, in the present specification, it is assumed that "nitride semiconductor" includes all semiconductors obtained by varying the composition ratios x, y, and z within their respective ranges in the chemical formula of B x In y Al z Ga 1-x-y-z N (0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1, x + y + z ≤ 1). Further, in the above chemical formula, it is assumed that semiconductors containing group V elements other than N (nitrogen), semiconductors containing various elements added to control various physical properties such as the conduction type, and semiconductors containing various elements inadvertently included are also included in the "nitride semiconductor".

[0184] In the present specification, regarding "electrically connected", in addition to the case of connecting by direct contact, it also includes the case of connecting via other conductive members or the like.

[0185] In the present specification, "vertical" includes not only strict verticality but also verticality including, for example, deviations in the manufacturing process, as long as it is substantially vertical.

[0186] As described above, the embodiments of the present invention have been described with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific structures of the respective elements included in the semiconductor device, as long as those skilled in the art can appropriately select from the publicly known range and similarly implement the present invention to obtain the same effects, they are included in the scope of the present invention.

[0187] A solution obtained by combining any two or more elements of the respective specific examples within a technically feasible range is included in the scope of the present invention as long as it includes the gist of the present invention.

[0188] In addition, all semiconductor devices that can be implemented by appropriately making design changes based on the semiconductor device described above as an embodiment of the present invention are included in the scope of the present invention as long as they include the gist of the present invention.

[0189] Furthermore, it should be understood that within the scope of the idea of the present invention, various modification examples and correction examples can be conceived by those skilled in the art, and these modification examples and correction examples also belong to the scope of the present invention.

[0190] Although several embodiments of the present invention have been described, these embodiments are merely illustrative and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and its equivalent scope.

[0191] [Description of Reference Numerals]

[0192] 11: First electrode; 11a: Upper surface; 13: Gate electrode; 13b: Gate electrode; 13t: Gate end portion; 13u: Other gate end portion; 14: Conductive portion; 14L: Wiring; 20: Second electrode; 21: First conductive portion; 21u: End portion; 22: Second conductive portion; 22b: Conductive portion; 22f: Conductive film; 22t: First end portion; 22u: First other end portion; 23: Third conductive portion; 23b: Conductive portion; 24: Fourth conductive portion; 24b: Conductive portion; 25, 26, 27: Conductive layer; 30: Semiconductor portion; 30s: Surface; 31: First semiconductor region; 32: Second semiconductor region; 32b: Semiconductor region; 32c: Second region; 32f: Upper surface; 32s: First region; 33: Third semiconductor region; 34: Fourth semiconductor region; 35: Fifth semiconductor region; 40: Insulating portion; 40s: End face; 41: First insulating region; 42: Second insulating region; 43: Third insulating region; 100, 101: Semiconductor device; F1: Opposing surface; L1 to L5: Length; T1, T2: Trench.

Claims

1. A semiconductor device comprising: A first electrode; A first conductive portion extending in a first direction from the first electrode towards the first conductive portion, the first conductive portion including a metal, metal oxide or metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru; A semiconductor portion of a first conductivity type including a first semiconductor region and a second semiconductor region, at least a part of the first semiconductor region being located between the first conductive portion and the first electrode, the first conductive portion being in Schottky contact with the first semiconductor region, and extending in a second direction intersecting the first direction from the first conductive portion towards the second semiconductor region; A second conductive portion in Schottky contact with the second semiconductor region, the second conductive portion including at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co, and at least a part of the second conductive portion being located between the first conductive portion and the second semiconductor region; A gate electrode, with at least a part of the second semiconductor region being located between the gate electrode and the second conductive portion; And An insulating portion including a first insulating region provided between the gate electrode and the second semiconductor region.

2. The semiconductor device according to claim 1, wherein The semiconductor device further includes a third conductive portion connected to the second semiconductor region, the third conductive portion including a metal, metal oxide or metal nitride containing at least one element selected from the group consisting of Ti, Ta, W, Cr, and Ru, The second conductive portion being located between the third conductive portion and the first semiconductor region.

3. The semiconductor device according to claim 2, wherein The second semiconductor region includes a first region and a second region located between the first region and the first electrode, The concentration of impurities of the first conductivity type in the first region is higher than the concentration of impurities of the first conductivity type in the second region, The third conductive portion is connected to the first region.

4. The semiconductor device according to claim 2 or 3, wherein The length of the second conductive portion in the first direction in contact with the second semiconductor region is longer than the length of the third conductive portion in the first direction in contact with the second semiconductor region.

5. The semiconductor device according to claim 4, wherein The second conductive portion includes a first end portion and a first other end portion, The first other end portion is located between the first end portion and the first electrode in the first direction, The gate electrode includes a gate end portion and a gate other end portion, The gate other end portion is located between the gate end portion and the first electrode in the first direction, The position of the gate end portion in the first direction is between the position of the first end portion in the first direction and the position of the first other end portion in the first direction.

6. The semiconductor device according to claim 2 or 3, wherein The first conductive portion and the third conductive portion are included in a conductive layer covering the second conductive portion.

7. The semiconductor device according to claim 6, wherein the end face of the conductive layer in the first direction of the insulating portion is in contact.

8. The semiconductor device according to any one of claims 1 to 3, wherein the semiconductor device further includes a fourth conductive portion, and the fourth conductive portion contains at least one element selected from the group consisting of Pt, Ni, Ir, Pd, Au, and Co, the second semiconductor region is located between the fourth conductive portion and the first electrode and is in contact with the fourth conductive portion.

9. The semiconductor device according to claim 8, wherein the first conductive portion is included in a conductive layer covering the second conductive portion and the fourth conductive portion.

10. The semiconductor device according to any one of claims 1 to 3, wherein the insulating portion further includes a second insulating region, the second semiconductor region is located between the second insulating region and the first electrode and is in contact with the second insulating region.

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