Nitride structure and semiconductor device

Abstract

To provide a nitride structure and a semiconductor device, of which characteristics can be improved.SOLUTION: According to an embodiment, a nitride structure contains: a base body; a nitride member containing Ga and N; and a lamination body to be provided between the base body and the nitride member in a first direction. The lamination body contains: a plurality of high composition films; and a plurality of low composition films. Each high composition film in the first direction as one of the plurality of high composition films is thinner than the thickness of the nitride member in the first direction of the nitride member. Each low composition film in the first direction as one of the plurality of low composition films is thinner than the thickness of the nitride member. Each high composition film and each low composition film are alternately provided along the first direction. The plurality of high composition film contains: a first film; and the other film. The first film contains: a first surface region; and a first inclination region, and the other film is along a crossed direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a nitride structure and a semiconductor device.

Background Art

[0002] For example, in a semiconductor device based on a nitride semiconductor, improvement in characteristics is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments of the present invention provide a nitride structure and a semiconductor device capable of improving characteristics.

Means for Solving the Problems

[0005] According to an embodiment of the present invention, the nitride structure includes a substrate, a nitride member containing Ga and N, and a laminate provided between the substrate and the nitride member in a first direction. The laminate includes a plurality of high-composition films containing Al x1 Ga 1-x1 N (0 < x1 ≤ 1), and Al x2 Ga 1-x2It includes a plurality of low-composition films including N(0≦x2<1, x2<x1). The high-composition film thickness of one of the plurality of high-composition films in the first direction is thinner than the nitride member thickness of the nitride member in the first direction. The low-composition film thickness of one of the plurality of low-composition films in the first direction is thinner than the nitride member thickness. The high-composition film and the low-composition film are alternately provided along the first direction. The plurality of high-composition films include a first film and another film. The first film is provided between the substrate and the other film. The first film includes a first surface region along a first surface region intersecting the first direction, a first other surface region along the intersection direction, a first inclined region along a first inclined direction inclined with respect to the first direction, and a first other inclined region along a first other inclined direction inclined with respect to the first direction and intersecting the first inclined direction. The direction from the first surface region to the first other surface region is along the intersection direction. The position of the first inclined region in the intersection direction is between the position of the first surface region in the intersection direction and the position of the first other surface region in the intersection direction. The position of the first other inclined region in the intersection direction is between the position of the first inclined region in the intersection direction and the position of the first other surface region in the intersection direction. The first inclined portion of the first inclined region is connected to the first surface region. The first other inclined portion of the first other inclined region is connected to the first other surface region. The first connection portion of the first inclined region is connected to the first other inclined region. The position of the first connection portion in the first direction is between the position of the substrate in the first direction and the position of the first surface region in the first direction. The other film is along the intersection direction.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

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Embodiments for Carrying Out the Invention

[0007] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of the sizes between parts, etc. are not necessarily the same as those in reality. Even when representing the same part, the dimensions and ratios may be represented differently in the drawings. In the present specification and each figure, the same reference numerals are given to the same elements as those described above with respect to the previously shown figures, and the detailed description will be omitted as appropriate.

[0008] (First Embodiment) FIGS. 1 and 2 are schematic cross-sectional views illustrating the nitride structure according to the first embodiment. As shown in FIG. 1, the nitride structure 210 according to the embodiment includes a substrate 60, a nitride member 10M, and a laminate 60S. The nitride member 10M contains Ga and N. The laminate 60S is provided between the substrate 60 and the nitride member 10M in the first direction D1.

[0009] The first direction D1 is the Z-axis direction. One direction perpendicular to the Z-axis direction is the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is the Y-axis direction. The substrate 60, the nitride member 10M, and the laminate 60S are in a layered form along the X - Y plane.

[0010] The laminate 60S includes a plurality of high-composition films 60H and a plurality of low-composition films 60L. The plurality of high-composition films 60H contain Al x1 Ga1-x1 It includes N(0 < x1 ≤ 1). The plurality of low-composition films 60L are Al x2 Ga 1-x2 It includes N(0 ≤ x2 < 1, x2 < x1). In one example, the plurality of high-composition films 60H are, for example, AlN films. The plurality of low-composition films 60L are, for example, AlGaN films. The plurality of low-composition films 60L may also be, for example, GaN films.

[0011] The high-composition film thickness t60H of the plurality of high-composition films 60H in one first direction D1 is thinner than the nitride member thickness t10M of the nitride member 10M in the first direction. The low-composition film thickness t60L of the plurality of low-composition films 60L in one first direction D1 is thinner than the nitride member thickness t10M.

[0012] The nitride member 10M may include a plurality of layers. For example, the high-composition film thickness t60H is thinner than the thickness along the first direction D1 of each of the plurality of layers. For example, the low-composition film thickness t60L is thinner than the thickness along the first direction D1 of each of the plurality of layers.

[0013] For example, the nitride member 10M is Al α1 Ga 1-α1 It includes a first semiconductor layer 10 containing AlGaN(0 ≤ α1 < 1), and Al α2 Ga 1-α2 It includes a second semiconductor layer 20 containing AlGaN(0 < α2 ≤ 1, α1 < α2). The first semiconductor layer 10 is provided between the laminate 60S and the second semiconductor layer 20 in the first direction D1. The first semiconductor layer 10 is, for example, a GaN layer. The second semiconductor layer 20 is, for example, an AlGaN layer.

[0014] The first semiconductor layer 10 includes a portion facing the second semiconductor layer 20. A carrier region is formed in this portion. The carrier region is, for example, a two-dimensional electron gas. In a semiconductor device based on the nitride structure 210, the carrier region is used for the operation of the semiconductor device.

[0015] For example, the high-composition film thickness t60H is thinner than the first semiconductor layer thickness t10 of the first semiconductor layer 10 in the first direction D1. For example, the high-composition film thickness t60H is thinner than the second semiconductor layer thickness t20 of the second semiconductor layer 20 in the first direction D1. For example, the low-composition film thickness t60L is thinner than the first semiconductor layer thickness t10. For example, the low-composition film thickness t60L is thinner than the second semiconductor layer thickness t20.

[0016] In this example, the nitride member 10M further includes an intermediate semiconductor layer 15. The intermediate semiconductor layer 15 is provided between the laminate 60S and the first semiconductor layer 10. The intermediate semiconductor layer 15 contains, for example, Ga and N. The composition ratio of the intermediate semiconductor layer 15 may be the same as that of the first semiconductor layer 10. The intermediate semiconductor layer 15 contains, for example, a first element (e.g., carbon). The first semiconductor layer 10 does not contain the first element. Or, the concentration of the first element in the first semiconductor layer 10 is lower than the concentration of the first element in the intermediate semiconductor layer 15.

[0017] The high-composition film thickness t60H is thinner than the intermediate semiconductor layer thickness t15 of the intermediate semiconductor layer 15 in the first direction D1. The low-composition film thickness t60L is thinner than the intermediate semiconductor layer thickness t15.

[0018] As shown in FIG. 1, for example, the high-composition films 60H and the low-composition films 60L are alternately provided along the first direction D1. For example, one of the plurality of high-composition films 60H is provided between one of the plurality of low-composition films 60L and another one of the plurality of low-composition films 60L. For example, one of the plurality of low-composition films 60L is provided between one of the plurality of high-composition films 60H and another one of the plurality of high-composition films 60H.

[0019] The laminate 60S is, for example, a superlattice laminate.

[0020] One of the plurality of high-composition films 60H and the plurality of low-composition films 60L includes a first film 61 and another film 68. Hereinafter, one of the plurality of high-composition films 60H and the plurality of low-composition films 60L includes a first film 61 and another film 68.

[0021] The first film 61 is provided between the substrate 60 and the other film 68. The first film 61 includes a V-shaped structure. The other film 68 includes a planar structure.

[0022] As described later, in the V-shaped structure, the direction of dislocations changes. By the confluence of a plurality of dislocations whose directions have changed, the dislocation density decreases. For example, in the nitride member 10M, a low dislocation density can be obtained. According to the embodiment, a nitride structure with improved characteristics can be obtained.

[0023] As shown in FIG. 1, for example, the depth of the V-shaped structure may decrease along the direction from the substrate 60 to the nitride member 10M. The V-shaped structure disappears in the other film 68.

[0024] For example, the laminate 60S includes a first portion 60A and a second portion 60B. The first portion 60A is provided between the substrate 60 and the second portion 60B. The high-composition film 60H included in the first portion 60A includes a first surface region 61a and a first inclined region 61p. The first surface region 61a extends along an intersection direction Dx that intersects the first direction D1. The first inclined region 61p extends along a first inclination direction Dp that is inclined with respect to the first direction D1. The high-composition film 60H included in the second portion 60B extends along the intersection direction Dx. The intersection direction Dx may be substantially perpendicular to the first direction D1.

[0025] In the first inclined region 61p, the direction of dislocations changes. By the confluence of a plurality of dislocations whose directions have changed, the dislocation density decreases. For example, in the nitride member 10M, a low dislocation density can be obtained. According to the embodiment, a nitride structure with improved characteristics can be obtained.

[0026] In the high-composition film 60H included in the first portion 60A, the length L61p along the first direction D1 of the first inclined region 61p decreases in the direction from the substrate 60 to the second portion 60B.

[0027] As shown in FIG. 2, for example, the first film 61 includes a first surface region 61a, a first other surface region 61b, a first inclined region 61p, and a first other inclined region 61q. The first surface region 61a extends along an intersection direction Dx that intersects the first direction D1. The intersection direction Dx may be substantially perpendicular to the first direction D1. The first other surface region 61b extends along the intersection direction Dx. The first inclined region 61p extends along a first inclination direction Dp that is inclined with respect to the first direction D1. The first other inclined region 61q extends along a first other inclination direction Dq that is inclined with respect to the first direction D1. The first other inclined region 61q is inclined with respect to the first direction D1 and intersects the first inclination direction Dp.

[0028] As shown in FIG. 2, the direction from the first surface region 61a to the first other surface region 61b extends along the intersection direction Dx. The position of the first inclined region 61p in the intersection direction Dx is between the position of the first surface region 61a in the intersection direction Dx and the position of the first other surface region 61b in the intersection direction Dx. The position of the first other inclined region 61q in the intersection direction Dx is between the position of the first inclined region 61p in the intersection direction Dx and the position of the first other surface region 61b in the intersection direction Dx.

[0029] As shown in FIG. 2, the first inclined portion 61px of the first inclined region 61p is connected to the first surface region 61a. The first other inclined portion 61qx of the first other inclined region 61q is connected to the first other surface region 61b. The first connection portion 61pc of the first inclined region 61p is connected to the first other inclined region 61q. The first connection portion 61pc corresponds to the bottom of the V-shaped structure.

[0030] The position of the first connection portion 61pc in the first direction D1 is between the position of the substrate 60 in the first direction D1 and the position of the first surface region 61a in the first direction D1.

[0031] The other film 68 extends along the intersection direction Dx.

[0032] In the first inclined region 61p and the first other inclined region 61q, the direction of the dislocations changes. By the confluence of a plurality of dislocations whose directions have changed, the dislocation density decreases. For example, in the nitride member 10M, a low dislocation density can be obtained.

[0033] For example, a part of one of the plurality of low-composition films 60L is provided between a first inclined region 61p and a first other inclined region 61q in the crossing direction Dx.

[0034] For example, the plurality of high-composition films 60H further includes a second film 62. The second film 62 is provided between the first film 61 and the other film 68 in the first direction D1. A part of the second film 62 is provided between the first inclined region 61p and the first other inclined region 61q in the crossing direction Dx.

[0035] As shown in FIG. 2, the second film 62 includes a second surface region 62a along the crossing direction Dx, a second other surface region 62b along the crossing direction Dx, a second inclined region 62p along the first inclined direction Dp, and a second other inclined region 62q along the first other inclined direction Dq.

[0036] The direction from the second surface region 62a to the second other surface region 62b is along the crossing direction Dx. The position of the second inclined region 62p in the crossing direction Dx is between the position of the second surface region 62a in the crossing direction Dx and the position of the second other surface region 62b in the crossing direction Dx. The position of the second other inclined region 62q in the crossing direction Dx is between the position of the second inclined region 62p in the crossing direction Dx and the position of the second other surface region 62b in the crossing direction Dx.

[0037] The second inclined portion 62px of the second inclined region 62p is connected to the second surface region 62a. The second other inclined portion 62qx of the second other inclined region 62q is connected to the second other surface region 62b. The second connection portion 62pc of the second inclined region 62p is connected to the second other inclined region 62q. The second connection portion 62pc corresponds to the bottom of the V-shaped structure.

[0038] The position of the second connection portion 62pc in the first direction D1 is between the position of the first connection portion 61pc in the first direction D1 and the position of the second surface region 62a in the first direction D1.

[0039] The second surface region 62a is between the first surface region 61a and the other film 68. The second other surface region 62b is between the first other surface region 61b and the other film 68. The second inclined region 62p is between the first inclined region 61p and the other film 68. The second other inclined region 62q is between the first other inclined region 61q and the other film 68.

[0040] A part of the second inclined region 62p and a part of the second other inclined region 62q are between the first inclined region 61p and the first other inclined region 61q in the crossing direction Dx.

[0041] As shown in FIG. 2, for example, let the distance along the crossing direction Dx between the second inclined portion 62px and the second other inclined portion 62qx be the distance dx2. Let the distance along the crossing direction Dx between the first inclined portion 61px and the first other inclined portion 61qx be the distance dx1. For example, the distance dx2 is shorter than the distance dx1. For example, the width of the V-shaped structure may decrease in the direction from the base body 60 to the other film 68.

[0042] For example, let the distance along the first direction D1 between the second connection portion 62pc and the second surface region 62a be the second distance dz2. Let the distance along the first direction D1 between the first connection portion 61pc and the first surface region 61a be the first distance dz1. For example, the second distance dz2 is shorter than the first distance dz1. For example, the depth of the V-shaped structure may decrease in the direction from the base body 60 to the other film 68.

[0043] For example, the position of the second connection portion 62pc in the crossing direction Dx may be between the position of the first connection portion 61pc in the crossing direction Dx and the position of the first other inclined portion 61qx in the crossing direction Dx. For example, the position of the second connection portion 62pc in the crossing direction Dx may be between the position of the first connection portion 61pc in the crossing direction Dx and the position of the first inclined portion 61px in the crossing direction Dx.

[0044] The position of the second connection portion 62pc in the intersection direction Dx is between the position of the first connection portion 61pc in the intersection direction Dx and the position of the first other inclined portion 61qx in the intersection direction Dx. Thus, in the second inclined region 62p and the second other inclined region 62q, the directions of more dislocations are likely to change. As a result, in the nitride member 10M, a low dislocation density is likely to be obtained.

[0045] The position of the second connection portion 62pc in the intersection direction Dx is between the position of the first connection portion 61pc in the intersection direction Dx and the position of the first inclined portion 61px in the intersection direction Dx. Thus, in the second inclined region 62p and the second other inclined region 62q, the directions of more dislocations are likely to change. As a result, in the nitride member 10M, a low dislocation density is likely to be obtained.

[0046] The plurality of high-composition films 60H may further include a third film 63. The third film 63 includes a third surface region 63a along the intersection direction Dx, a third other surface region 63b along the intersection direction Dx, a third inclined region 63p along the first inclined direction Dp, and a third other inclined region 63q along the first other inclined direction Dq.

[0047] The direction from the third surface region 63a to the third other surface region 63b is along the intersection direction Dx. The position of the third inclined region 63p in the intersection direction Dx is between the position of the third surface region 63a in the intersection direction Dx and the position of the third other surface region 63b in the intersection direction Dx. The position of the third other inclined region 63q in the intersection direction Dx is between the position of the third inclined region 63p in the intersection direction Dx and the position of the third other surface region 63b in the intersection direction Dx.

[0048] The third inclined portion 63px of the third inclined region 63p is connected to the third surface region 63a. The third other inclined portion 63qx of the third other inclined region 63q is connected to the third other surface region 63b. The third connection portion 63pc of the third inclined region 63p is connected to the third other inclined region 63q. The position of the third connection portion 63pc in the first direction D1 is between the position of the second connection portion 62pc in the first direction D1 and the position of the third surface region 63a in the first direction D1.

[0049] The third surface region 63a is between the second surface region 62a and the other film 68. The third other surface region 63b is between the second other surface region 62b and the other film 68. The third inclined region 63p is between the second inclined region 62p and the other film 68. The third other inclined region 63q is between the second other inclined region 62q and the other film 68.

[0050] As shown in FIG. 2, let the distance along the first direction D1 between the third connection portion 63pc and the third surface region 63a be the third distance dz3. As already described, let the distance along the first direction D1 between the first connection portion 61pc and the first surface region 61a be the first distance dz1. The third distance dz3 is shorter than the first distance dz1. As already described, let the distance along the first direction D1 between the second connection portion 62pc and the second surface region 62a be the second distance dz2. The third distance dz3 may be shorter than the second distance dz2. The depth of the V-shaped structure may decrease in the direction from the base 60 to the other film 68.

[0051] For example, let the distance along the crossing direction Dx between the third inclined portion 63px and the third other inclined portion 63qx be the distance dx3. The distance dx3 is shorter than the distance dx1. The distance dx3 may be shorter than the distance dx2. The width of the V-shaped structure may decrease in the direction from the base 60 to the other film 68.

[0052] For example, the direction from the first inclined region 61p to the third inclined region 63p is along the first direction D1. The direction from the first other inclined region 61q to the third other inclined region 63q is along the first direction D1.

[0053] For example, the position of the third connection portion 63pc in the crossing direction Dx may be between the position of the second connection portion 62pc in the crossing direction Dx and the position of the second other inclined portion 62qx in the crossing direction Dx. For example, the position of the third connection portion 63pc in the crossing direction Dx may be between the position of the second connection portion in the crossing direction Dx and the position of the second inclined portion 62px in the crossing direction Dx.

[0054] The position of the third connection portion 63pc in the intersection direction Dx is between the position of the second connection portion 62pc in the intersection direction Dx and the position of the second other inclined portion 62qx in the intersection direction Dx. Thus, in the third inclined region 63p and the third other inclined region 63q, the directions of more dislocations are likely to change. As a result, in the nitride member 10M, a low dislocation density is likely to be obtained.

[0055] The position of the third connection portion 63pc in the intersection direction Dx is between the position of the second connection portion 62pc in the intersection direction Dx and the position of the second inclined portion 62px in the intersection direction Dx. Thus, in the third inclined region 63p and the third other inclined region 63q, the directions of more dislocations are likely to change. As a result, in the nitride member 10M, a low dislocation density is likely to be obtained.

[0056] For example, the position of the second connection portion 62pc in the intersection direction Dx may be between the position of the third connection portion 63pc in the intersection direction Dx and the position of the first connection portion 61pc in the intersection direction Dx.

[0057] The position of the second connection portion 62pc in the intersection direction Dx is between the position of the third connection portion 63pc in the intersection direction Dx and the position of the first connection portion 61pc in the intersection direction Dx. Thus, in the third inclined region 63p and the third other inclined region 63q, the directions of more dislocations are likely to change. As a result, in the nitride member 10M, a low dislocation density is likely to be obtained.

[0058] As shown in FIG. 1, the nitride structure 210 may further include a first intermediate layer 60a. The first intermediate layer 60a is provided between the substrate 60 and the laminate 60S. The first intermediate layer 60a is, for example, Al z1 Ga 1-z1It includes N(0 < z1 < 1). The first intermediate layer 60a is, for example, an AlGaN layer. The first intermediate layer 60a includes a protruding portion 60p that protrudes toward the laminate 60S. The direction from at least a part of the protruding portion 60p to the first connection portion 61pc follows the first direction D1. For example, at least a part of the protruding portion 60p may overlap with the first inclined region 61p in the first direction D1. For example, at least a part of the protruding portion 60p may overlap with the first other inclined region 61q in the first direction D1.

[0059] By providing the protruding portion 60p, a V-shaped structure is likely to be formed. By providing the protruding portion 60p, the first inclined region 61p and the first other inclined region 61q are likely to be formed. In these inclined regions, the direction of the dislocations changes. As a result, a low dislocation density can be obtained in the nitride member 10M.

[0060] The height h60p (see FIG. 1) of the protruding portion 60p may be, for example, 5 nm or more and 200 nm or less.

[0061] As shown in FIG. 1, the nitride structure 210 may further include a second intermediate layer 60b. The second intermediate layer 60b is provided between the substrate 60 and the first intermediate layer 60a. The second intermediate layer 60b contains Al z2 Ga 1-z2 N(0 < z2 ≤ 1). The second intermediate layer 60b may be, for example, an AlN layer.

[0062] FIG. 3 is a schematic cross-sectional view illustrating the nitride structure according to the first embodiment. As shown in FIG. 3, the laminate 60S includes a plurality of dislocations DD1. One of the plurality of dislocations DD1 passes through the first inclined region 61p. Another one of the plurality of dislocations DD1 passes through the first other inclined region 61q. The direction of one of the plurality of dislocations DD1 changes in the first inclined region 61p. The direction of another one of the plurality of dislocations DD1 changes in the first other inclined region 61q. The dislocation DD1 passing through the first inclined region 61p merges with the dislocation DD1 passing through the first other inclined region 61q. As a result, the number of the plurality of dislocations DD1 decreases. The inclined region reduces the dislocation density.

[0063] For example, the density of a plurality of dislocations DD1 reaching the other film 68 decreases. For example, the density of the dislocations DD1 passing through the other film 68 is lower than the density of the dislocations DD1 passing through the first film 61. For example, in the nitride member 10M, a low dislocation density can be obtained.

[0064] For example, the high-composition film thickness t60H is 3 nm or more and 20 nm or less. For example, the low-composition film thickness t60L is 5 nm or more and 50 nm or less. For example, the nitride member thickness t10M is 50 nm or more and 3000 nm or less.

[0065] For example, the first semiconductor layer thickness t10 is 50 nm or more and 2000 nm or less. For example, the second semiconductor layer thickness t20 is 10 nm or more and 50 nm or less. For example, the intermediate semiconductor layer thickness t15 is 100 nm or more and 2000 nm or less.

[0066] For example, the nitride member thickness t10M may be 10 times or more and 1000 times or less the high-composition film thickness t60H. For example, the nitride member thickness t10M may be 2 times or more and 600 times or less the low-composition film thickness t60L.

[0067] For example, the first semiconductor layer thickness t10 may be 10 times or more and 1000 times or less the high-composition film thickness t60H. For example, the first semiconductor layer thickness t10 may be 2 times or more and 600 times or less the low-composition film thickness t60L.

[0068] For example, the second semiconductor layer thickness t20 may be 2 times or more and 20 times or less the high-composition film thickness t60H. For example, the second semiconductor layer thickness t20 may be 2 times or more and 10 times or less the low-composition film thickness t60L.

[0069] For example, the intermediate semiconductor layer thickness t15 may be 10 times or more and 1000 times or less the high-composition film thickness t60H. For example, the intermediate semiconductor layer thickness t15 may be 2 times or more and 600 times or less the low-composition film thickness t60L.

[0070] For example, the position of the second connection portion 62pc in the crossing direction Dx may be between the position of the first connection portion 61pc in the crossing direction Dx and the position of the first other inclined portion 61qx in the crossing direction Dx. For example, the position of the second connection portion 62pc in the crossing direction Dx may be between the position of the first connection portion 61pc in the crossing direction Dx and the position of the first inclined portion 61px in the crossing direction Dx. Thereby, the dislocations that have merged in the first inclined region 61p or the first other inclined region 61q change the direction of the dislocations again in the second inclined region 62p or the second other inclined region 62q. By the confluence of a plurality of dislocations whose directions have changed, the dislocation density further decreases. Thereby, in the nitride member 10M, a lower dislocation density is likely to be obtained.

[0071] For example, the position of the second connection portion 62pc in the crossing direction Dx may be between the position of the third connection portion 63pc in the crossing direction Dx and the position of the first connection portion 61pc in the crossing direction Dx. Thereby, the dislocations that have merged in the first inclined region 61p or the first other inclined region 61q change the direction of the dislocations again in the second inclined region 62p or the second other inclined region 62q. By the confluence of a plurality of dislocations whose directions have changed, the dislocation density further decreases. Thereby, in the nitride member 10M, a lower dislocation density is likely to be obtained.

[0072] In an embodiment, one of the plurality of high-composition films 60H may be in contact with the nitride member 10M. Alternatively, one of the plurality of low-composition films 60L may be in contact with the nitride member 10M. One of the plurality of high-composition films 60H may be in contact with the first intermediate layer 60a. Alternatively, one of the plurality of low-composition films 60L may be in contact with the first intermediate layer 60a.

[0073] The number of the plurality of high-composition films 60H may be, for example, 4 or more and 200 or less. The number of the plurality of low-composition films 60L may be, for example, 4 or more and 200 or less.

[0074] For example, among the plurality of high-composition films 60H, the other film 68 may be closest to the nitride member 10M. In the embodiment, in the second portion 60B of the laminate 60S, the V-shaped structure disappears. For example, the other film 68 among the plurality of high-composition films 60H does not include a V-shaped structure along the crossing direction Dx.

[0075] For example, in the laminate 60S, a first reference example in which the V-shaped structure does not disappear can be considered. In the first reference example, the V-shaped structure is filled in the nitride member 10M. In the first reference example, it is difficult to reduce dislocations. For example, the dislocation density in the nitride member 10M of the first reference example is 1.6×10 10 / cm 2 . The insulation of the laminate 60S is likely to deteriorate. Current easily flows in the V-shaped structure, and current leakage is likely to occur. The breakdown voltage is likely to decrease.

[0076] On the other hand, in the embodiment, in the other film 68 included in the plurality of high-composition films 60H, the V-shaped structure disappears. As a result, a lower dislocation density can be easily obtained. High insulation can be easily obtained. A high breakdown voltage can be easily obtained.

[0077] On the other hand, a second reference example in which the laminate 60S does not include a V-shaped structure can be considered. In the second reference example, it is difficult to reduce dislocations. For example, the dislocation density in the nitride member 10M of the second reference example is 2.0×10 10 / cm 2 . On the other hand, in the embodiment in which the laminate 60S includes a V-shaped structure, the dislocation density in the nitride member 10M is 1.0×10 10 / cm 2 .

[0078] In an embodiment, for example, the conditions during the formation of at least a part of the first portion 60A of the laminate 60S are different from the conditions during the formation of the second portion 60B of the laminate 60S. For example, when the temperature in film formation is low, a V-shaped structure (inclined region) is more likely to be formed compared to when the temperature is high. For example, when the V / III ratio in film formation is low, a V-shaped structure (inclined region) is more likely to be formed compared to when the V / III ratio is high. By changing such formation conditions, the above-described laminate 60S can be obtained. The V / III ratio is the ratio of the supply amount of group V raw material to the supply amount of group III raw material. In the first portion 60A, at least either the temperature or the V / III ratio in film formation may be changed. For example, the V-shaped structure is likely to change.

[0079] In one example, the temperature during the formation of the first film 61 is lower than the temperature during the formation of the other film 68. In one example, the V / III ratio during the formation of the first film 61 is lower than the V / III ratio during the formation of the other film 68.

[0080] In an embodiment, the length along the first direction D1 of the first portion 60A where the V-shaped structure changes may be shorter than the length along the first direction D1 of the second portion 60B that does not include the V-shaped structure. By the length along the first direction D1 of the first portion 60A being shorter than the length along the first direction D1 of the second portion 60B, for example, high insulation can be easily obtained. For example, high breakdown voltage can be easily obtained.

[0081] In an embodiment, one or more additional high-composition films 60H may be provided between the first intermediate layer 60a and the first film 61. One or more additional high-composition films 60H may be provided between the first film 61 and the second film 62. One or more additional high-composition films 60H may be provided between the second film 62 and the third film 63. One or more additional high-composition films 60H may be provided between the third film 63 and the other film 68. A plurality of the other films 68 may be provided.

[0082] FIGS. 4 and 5 are electron microscope images illustrating a nitride structure according to the first embodiment. These figures are TEM (Transmission Electron Microscope) images of one sample of the nitride structure 210. As shown in FIG. 4, the length along the first direction D1 of the first portion 60A may be longer than the length along the first direction D1 of the second portion 60B. By making the length along the first direction D1 of the first portion 60A longer than the length along the first direction D1 of the second portion 60B, a lower dislocation density can be easily obtained. As shown in FIG. 5, at least a part of the V-shaped structure may be curved.

[0083] In an embodiment, the substrate 60 may be, for example, a silicon substrate. The substrate 60 may include, for example, sapphire, SiC, or GaN.

[0084] For example, the concentration of oxygen in the first intermediate layer 60a may be lower than the concentration of oxygen in the laminate 60S. The concentration of oxygen in the first intermediate layer 60a is, for example, 3×10 14 / cm 3 or more and 4×10 16 cm 3 or less. For example, the protrusion 60p is easily formed. High insulation can be easily obtained.

[0085] For example, the concentration of carbon in the first intermediate layer 60a may be higher than the concentration of carbon in the laminate 60S. The concentration of carbon in the first intermediate layer 60a is, for example, 1×10 19 / cm 3 or more and 8×10 19 cm 3 or less. For example, the protrusion 60p is easily formed. A low dislocation density can be easily obtained.

[0086] (Second Embodiment) FIG. 6 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. As shown in FIG. 6, the semiconductor device 110 according to the embodiment includes the nitride structure 210 according to the first embodiment, a first electrode 51, a second electrode 52, and a third electrode 53.

[0087] As already described, the nitride member 10M includes the first semiconductor layer 10 and the second semiconductor layer 20. The nitride member 10M may further include an intermediate semiconductor layer 15. The intermediate semiconductor layer 15 is provided as necessary and may be omitted.

[0088] The second direction D2 from the first electrode 51 to the second electrode 52 intersects the first direction D1. The second direction D2 may be, for example, the X-axis direction. The position of the third electrode 53 in the second direction D2 is between the position of the first electrode 51 in the second direction D2 and the position of the second electrode 52 in the second direction D2.

[0089] The second semiconductor layer 20 includes a first semiconductor portion 21 and a second semiconductor portion 22. The direction from the first semiconductor portion 21 to the second semiconductor portion 22 is along the second direction D2. The first electrode 51 is electrically connected to the first semiconductor portion 21. The second electrode 52 is electrically connected to the second semiconductor portion 22.

[0090] The current flowing between the first electrode 51 and the second electrode 52 is controlled by the potential of the third electrode 53. The potential of the third electrode 53 may be, for example, a potential based on the potential of the first electrode 51. The first electrode 51 functions as a source electrode, for example. The second electrode 52 functions as a drain electrode. The third electrode 53 functions as a gate electrode. The semiconductor device 110 is a transistor, for example.

[0091] The first semiconductor layer 10 includes a region facing the second semiconductor layer 20. A carrier region is formed in this region. The carrier region is, for example, a two-dimensional electron gas. The semiconductor device 110 is a HEMT (High Electron Mobility Transistor), for example.

[0092] The semiconductor device 110 includes a laminate 60S of the nitride structure 210 according to the first embodiment. In the semiconductor device 110, good crystallinity is obtained. For example, a low dislocation density is obtained.

[0093] As shown in FIG. 6, in this example, at least a part of the third electrode 53 is provided between the first semiconductor portion 21 and the second semiconductor portion 22 in the second direction D2. The third electrode 53 is, for example, a recessed gate electrode.

[0094] For example, the first semiconductor layer 10 includes a first partial region 10a, a second partial region 10b, a third partial region 10c, a fourth partial region 10d, and a fifth partial region 10e. The direction from the first partial region 10a to the first electrode 51 is along the first direction D1. The direction from the second partial region 10b to the second electrode 52 is along the first direction D1. The direction from the third partial region 10c to the third electrode 53 is along the first direction D1.

[0095] The position of the fourth partial region 10d in the second direction D2 is between the position of the first partial region 10a in the second direction D2 and the position of the third partial region 10c in the second direction D2. The position of the fifth partial region 10e in the second direction D2 is between the position of the third partial region 10c in the second direction D2 and the position of the second partial region 10b in the second direction D2.

[0096] The direction from the fourth partial region 10d to the first semiconductor portion 21 is along the first direction D1. The direction from the fifth partial region 10e to the second semiconductor portion 22 is along the first direction D1. In this example, a part of the third electrode 53 is between the fourth partial region 10d and the fifth partial region 10e in the second direction D2. A high threshold voltage can be obtained. For example, a normally-off operation can be obtained.

[0097] As shown in FIG. 6, the semiconductor device 110 may further include a first insulating member 41. The first insulating member 41 includes a first insulating portion 41p, and the first insulating portion 41p is provided between the third electrode 53 and the nitride member 10M. The first insulating portion 41p functions as, for example, a gate insulating film.

[0098] FIG. 7 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. As shown in FIG. 7, the semiconductor device 111 according to the embodiment includes a nitride structure 210 according to the first embodiment, a first electrode 51, a second electrode 52, and a third electrode 53. In the semiconductor device 111, the third electrode 53 does not overlap with the second semiconductor layer 20 in the second direction D2. The configuration of the semiconductor device 111 except this may be the same as that of the semiconductor device 110.

[0099] The semiconductor device 111 can obtain, for example, a normally-on operation. In the semiconductor device 111, the first insulating member 41 may be omitted. For example, it can be used as a high-frequency switching element.

[0100] In the embodiment, information regarding the shape of the nitride region and the like can be obtained, for example, by electron microscope observation. Information regarding the composition and element concentration in the nitride region can be obtained, for example, by EDX (Energy Dispersive X-ray Spectroscopy) or SIMS (Secondary Ion Mass Spectrometry). Information regarding the composition in the nitride region may be obtained, for example, by X-ray diffraction measurement or Reciprocal Space Mapping.

[0101] The embodiment may include the following technical solutions. (Technical Solution 1) A substrate, A nitride member containing Ga and N, A laminate provided between the substrate and the nitride member in the first direction, Comprising, The laminate, Al x1 Ga 1-x1 A plurality of high-composition films containing N (0 < x1 ≤ 1), Al x2 Ga 1-x2 A plurality of low-composition films containing N (0 ≤ x2 < 1, x2 < x1), Including, The high-composition film thickness of one of the plurality of high-composition films in the first direction is thinner than the nitride member thickness of the nitride member in the first direction. The low-composition film thickness of one of the plurality of low-composition films in the first direction is thinner than the nitride member thickness. The high-composition film and the low-composition film are alternately provided along the first direction. The plurality of high-composition films include a first film and another film, and the first film is provided between the substrate and the other film. The first film includes a first surface region along a crossing direction intersecting with the first direction, a first other surface region along the crossing direction, a first inclined region along a first inclined direction inclined with respect to the first direction, and a first other inclined region along a first other inclined direction inclined with respect to the first direction and intersecting with the first inclined direction. The direction from the first surface region to the first other surface region is along the crossing direction. The position of the first inclined region in the crossing direction is between the position of the first surface region in the crossing direction and the position of the first other surface region in the crossing direction. The position of the first other inclined region in the crossing direction is between the position of the first inclined region in the crossing direction and the position of the first other surface region in the crossing direction. The first inclined portion of the first inclined region is connected to the first surface region. The first other inclined portion of the first other inclined region is connected to the first other surface region. The first connection portion of the first inclined region is connected to the first other inclined region. The position of the first connection portion in the first direction is between the position of the substrate in the first direction and the position of the first surface region in the first direction. The other film is a nitride structure along the crossing direction.

[0102] (Technical solution 2) A part of one of the plurality of low-composition films is a nitride structure according to Technical Proposal 1 provided between the first inclined region and the first other inclined region in the crossing direction.

[0103] (Technical Proposal 3) The plurality of high-composition films further includes a second film, The second film is provided between the first film and the other film in the first direction, A part of the second film is a nitride structure according to Technical Proposal 2 provided between the first inclined region and the first other inclined region in the crossing direction.

[0104] (Technical Proposal 4) The plurality of high-composition films further includes a second film, The second film, a second surface region along the crossing direction, a second other surface region along the crossing direction, a second inclined region along the first inclined direction, a second other inclined region along the first other inclined direction, and includes, The direction from the second surface region to the second other surface region is along the crossing direction, The position of the second inclined region in the crossing direction is between the position of the second surface region in the crossing direction and the position of the second other surface region in the crossing direction, The position of the second other inclined region in the crossing direction is between the position of the second inclined region in the crossing direction and the position of the second other surface region in the crossing direction, The second inclined portion of the second inclined region is connected to the second surface region, The second other inclined portion of the second other inclined region is connected to the second other surface region, The second connection portion of the second inclined region is connected to the second other inclined region, The position of the second connection portion in the first direction is between the position of the first connection portion in the first direction and the position of the second surface region in the first direction, The second surface region is between the first surface region and the other film, The second other surface region is between the first other surface region and the other film, The second inclined region is between the first inclined region and the other film, The second other inclined region is between the first other inclined region and the other film, A part of the second inclined region and a part of the second other inclined region are between the first inclined region and the first other inclined region in the intersecting direction, the nitride structure according to Technical Proposal 2.

[0105] (Technical Proposal 5) The distance along the intersecting direction between the second inclined portion and the second other inclined portion is shorter than the distance along the intersecting direction between the first inclined portion and the first other inclined portion, the nitride structure according to Technical Proposal 4.

[0106] (Technical Proposal 6) The second distance along the first direction between the second connection portion and the second surface region is shorter than the first distance along the first direction between the first connection portion and the first surface region, the nitride structure according to Technical Proposal 4 or 5.

[0107] (Technical Proposal 7) The position of the second connection portion in the intersecting direction is between the position of the first connection portion in the intersecting direction and the position of the first other inclined portion in the intersecting direction, or, The position of the second connection portion in the intersecting direction is between the position of the first connection portion in the intersecting direction and the position of the first inclined portion in the intersecting direction, the nitride structure according to Technical Proposal 4.

[0108] (Technical Proposal 8) The plurality of high-composition films further includes a third film, The third film is, A third surface region along the intersecting direction, A third other surface region along the intersecting direction, A third inclined region along the first inclined direction, a third other inclined region along the first other inclined direction, including the direction from the third surface region to the third other surface region is along the intersection direction, the position of the third inclined region in the intersection direction is between the position of the third surface region in the intersection direction and the position of the third other surface region in the intersection direction, the position of the third other inclined region in the intersection direction is between the position of the third inclined region in the intersection direction and the position of the third other surface region in the intersection direction, the third inclined portion of the third inclined region is connected to the third surface region, the third other inclined portion of the third other inclined region is connected to the third other surface region, the third connection portion of the third inclined region is connected to the third other inclined region, the position of the third connection portion in the first direction is between the position of the second connection portion in the first direction and the position of the third surface region in the first direction, the third surface region is between the second surface region and the other film, the third other surface region is between the second other surface region and the other film, the third inclined region is between the second inclined region and the other film, the third other inclined region is between the second other inclined region and the other film, The nitride structure according to Technical Solution 4, wherein a third distance along the first direction between the third connection portion and the third surface region is shorter than a first distance along the first direction between the first connection portion and the first surface region.

[0109] (Technical Solution 9) The nitride structure according to Technical Solution 8, wherein the direction from the first inclined region to the third inclined region is along the first direction.

[0110] (Technical Solution 10) Al provided between the substrate and the laminate z1 Ga 1-z1Further comprising a first intermediate layer including N(0 < z1 < 1), The first intermediate layer includes a protruding portion protruding toward the laminate, At least a part of the protruding portion is in the direction to the first connection portion along the first direction, the nitride structure according to any one of Technical Proposals 1 to 9.

[0111] (Technical Proposal 11) The dislocations passing through the first inclined region merge with the dislocations passing through the first other inclined direction, the nitride structure according to any one of Technical Proposals 1 to 10.

[0112] (Technical Proposal 12) The density of the dislocations passing through the other film is lower than the density of the dislocations passing through the first film, the nitride structure according to any one of Technical Proposals 1 to 10.

[0113] (Technical Proposal 13) A substrate, A nitride member containing Ga and N, A laminate provided between the substrate and the nitride member in the first direction, Comprising, The laminate is, Al x1 Ga 1-x1 A plurality of high-composition films containing N(0 < x1 ≤ 1), Al x2 Ga 1-x2 A plurality of low-composition films containing N(0 ≤ x2 < 1, x2 < x1), Including, The high-composition film thickness of one of the plurality of high-composition films in the first direction is thinner than the nitride member thickness of the nitride member in the first direction, The low-composition film thickness of one of the plurality of low-composition films in the first direction is thinner than the nitride member thickness, The high-composition films and the low-composition films are alternately provided along the first direction, The laminate includes a first part and a second part, The first part is provided between the substrate and the second part, The high-composition film included in the first portion includes a first surface region along a crossing direction intersecting the first direction and a first inclined region along a first inclined direction inclined with respect to the first direction. The high-composition film included in the second portion is a nitride structure along the crossing direction.

[0114] (Technical Proposal 14) The nitride structure according to Technical Proposal 13, wherein in the high-composition film included in the first portion, the length of the first inclined region along the first direction decreases in the direction from the substrate to the second portion.

[0115] (Technical Proposal 15) The nitride structure according to Technical Proposal 13 or 14, wherein in the high-composition film included in the first portion, the length of the first inclined region along the crossing direction decreases in the direction from the substrate to the second portion.

[0116] (Technical Proposal 16) Al is provided between the substrate and the laminate z1 Ga 1-z1 Further including a first intermediate layer containing N(0 < z1 < 1), The first intermediate layer includes a protruding portion protruding toward the laminate, The nitride structure according to Technical Proposal 13 or 14, wherein at least a part of the protruding portion overlaps with the first inclined region in the first direction.

[0117] (Technical Proposal 17) Al is provided between the substrate and the first intermediate layer z2 Ga 1-z2 The nitride structure according to Technical Proposal 10 or 16, further including a second intermediate layer containing N(0 < z2 ≤ 1).

[0118] (Technical Proposal 18) The nitride member is Al α1 Ga 1-α1 A first semiconductor layer containing N(0 ≤ α1 < 1), and Al α2 Ga 1-α2A second semiconductor layer containing N(0 < α2 ≤ 1, α1 < α2), including The first semiconductor layer is the nitride structure according to any one of Technical Solutions 1 to 17 provided between the laminate and the second semiconductor layer in the first direction.

[0119] (Technical Solution 19) The nitride structure according to any one of Technical Solutions 1 to 18, a first electrode, a second electrode, a third electrode, comprising The nitride member is Al α1 Ga 1-α1 a first semiconductor layer containing N(0 ≤ α1 < 1), Al α2 Ga 1-α2 a second semiconductor layer containing N(0 < α2 ≤ 1, α1 < α2), including The first semiconductor layer is provided between the laminate and the second semiconductor layer, The second direction from the first electrode to the second electrode intersects the first direction, The position of the third electrode in the second direction is between the position of the first electrode in the second direction and the position of the second electrode in the second direction, The second semiconductor layer includes a first semiconductor portion and a second semiconductor portion, The direction from the first semiconductor portion to the second semiconductor portion is along the second direction, The first electrode is electrically connected to the first semiconductor portion, The second electrode is electrically connected to the second semiconductor portion, a semiconductor device.

[0120] (Technical Solution 20) Further comprising a first insulating member including a first insulating portion, The first insulating portion is provided between the third electrode and the nitride member, the semiconductor device according to Technical Solution 19.

[0121] (Technical Solution 21) The position of the second connection portion in the intersecting direction is between the position of the first connection portion in the intersecting direction and the position of the third connection portion in the intersecting direction, for the nitride structure according to Technical Proposal 8 or 9.

[0122] (Technical Proposal 22) The high-composition film thickness is 3 nm or more and 20 nm or less, The low-composition film thickness is 5 nm or more and 50 nm or less, The nitride member thickness is 50 nm or more and 3000 nm or less, for the nitride structure according to any one of Technical Proposals 1 to 18.

[0123] (Technical Proposal 23) At least a part of the third electrode is provided between the first semiconductor portion and the second semiconductor portion in the second direction, for the semiconductor device according to Technical Proposal 19 or 20.

[0124] According to the embodiment, a nitride structure and a semiconductor device capable of improving characteristics can be provided.

[0125] In this specification, the "electrically connected state" includes a state in which a plurality of conductors are physically in contact and an electric current flows between these plurality of conductors. The "electrically connected state" includes a state in which another conductor is inserted between a plurality of conductors and an electric current flows between these plurality of conductors.

[0126] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific configurations of each element such as the nitride region and the substrate included in the nitride structure, the present invention can be similarly implemented by appropriately selecting from the range known to those skilled in the art, and as long as the same effects can be obtained, it is included in the scope of the present invention.

[0127] Also, combinations of any two or more elements of each specific example within a technically possible range are included in the scope of the present invention as long as they include the gist of the present invention.

[0128] In addition, based on the nitride structure and the semiconductor device described above as embodiments of the present invention, all nitride structures and semiconductor devices that can be appropriately designed and modified by those skilled in the art also belong to the scope of the present invention as long as they include the gist of the present invention.

[0129] In addition, those skilled in the art can conceive of various modification examples and correction examples within the scope of the idea of the present invention, and these modification examples and correction examples are also understood to belong to the scope of the present invention.

[0130] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, 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.

Explanation of Reference Numerals

[0131] 10, 20: First and second semiconductor layers, 10M: Nitride member, 10a - 10e: First to fifth partial regions, 15: Intermediate semiconductor layer, 21, 22: First and second semiconductor parts, 41: First insulating member, 41p: First insulating part, 51 - 53: First to third electrodes, 60: Substrate, 60A, 60B: First and second parts, 60H: High - composition film, 60L: Low - composition film, 60S: Laminate, 60a, 60b: First and second intermediate layers, 60p: Protrusion, 61 - 63: First to third films, 61a - 63a: First to third surface regions, 61b - 63b: First to third other - surface regions, 61p - 63p: First to third inclined regions, 61pc - 63pc: First to third connection parts, 61px - 63px: First to third inclined parts, 61q - 63q: First to third other - inclined regions, 61qx - 64qx: First to third other - inclined parts, 68: Other film, 110, 111: Semiconductor devices, 210: Nitride structure, D1, D2: First and second directions, DD1: Dislocation, Dp: First inclined direction, Dq: First other - inclined direction, Dx: Crossing direction, dx1 - dx3: Distances, dz1 - dz3: First to third distances, h60p: Height, t10: First semiconductor layer thickness, t10M: Nitride member thickness, t15: Intermediate semiconductor layer thickness, t20: Second semiconductor layer thickness, t60H: High - composition film thickness, t60L: Low - composition film thickness

Claims

1. a substrate, a nitride member containing Ga and N, a laminate provided between the substrate and the nitride member in a first direction, comprising, the laminate, Al ｘ１ Ga １－ｘ１ A plurality of high-composition films containing N(0 < x1 ≤ 1), Al ｘ２ Ga １－ｘ２ a plurality of low-composition films containing N (0 ≦ x2 < 1, x2 < x1), including, the high-composition film thickness of one of the plurality of high-composition films in the first direction is thinner than the nitride member thickness of the nitride member in the first direction, the low-composition film thickness of one of the plurality of low-composition films in the first direction is thinner than the nitride member thickness, the high-composition film and the low-composition film are alternately provided along the first direction, the plurality of high-composition films include a first film and another film, and the first film is provided between the substrate and the other film, the first film, a first surface region along a first surface direction intersecting the first direction, a first other surface region along the first surface direction, a first inclined region along a first inclined direction inclined with respect to the first direction, a first other inclined region along a first other inclined direction inclined with respect to the first direction and intersecting the first inclined direction, including, the direction from the first surface region to the first other surface region is along the first surface direction, the position of the first inclined region in the first surface direction is between the position of the first surface region in the first surface direction and the position of the first other surface region in the first surface direction, the position of the first other inclined region in the first surface direction is between the position of the first inclined region in the first surface direction and the position of the first other surface region in the first surface direction, the first inclined portion of the first inclined region is connected to the first surface region, the first other inclined portion of the first other inclined region is connected to the first other surface region, the first connection portion of the first inclined region is connected to the first other inclined region, the position of the first connection portion in the first direction is between the position of the substrate in the first direction and the position of the first surface region in the first direction, the other film is a nitride structure along the first surface direction.

2. A part of one of the plurality of low-composition films is the nitride structure according to claim 1 provided between the first inclined region and the first other inclined region in the first surface direction.

3. the plurality of high-composition films further include a second film, the second film, a second surface region along the first surface direction, a second other surface region along the first surface direction, a second inclined region along the first inclined direction, a second other inclined region along the first other inclined direction, including, the direction from the second surface region to the second other surface region is along the first surface direction, The position of the second inclined region in the intersection direction is between the position of the second surface region in the intersection direction and the position of the second other surface region in the intersection direction. The position of the second other inclined region in the intersection direction is between the position of the second inclined region in the intersection direction and the position of the second other surface region in the intersection direction. The second inclined portion of the second inclined region is connected to the second surface region. The second other inclined portion of the second other inclined region is connected to the second other surface region. The second connection portion of the second inclined region is connected to the second other inclined region. The position of the second connection portion in the first direction is between the position of the first connection portion in the first direction and the position of the second surface region in the first direction. The second surface region is between the first surface region and the other film. The second other surface region is between the first other surface region and the other film. The second inclined region is between the first inclined region and the other film. The second other inclined region is between the first other inclined region and the other film. A part of the second inclined region and a part of the second other inclined region are between the first inclined region and the first other inclined region in the intersection direction. The nitride structure according to claim 2.

4. The distance along the intersection direction between the second inclined portion and the second other inclined portion is shorter than the distance along the intersection direction between the first inclined portion and the first other inclined portion. The nitride structure according to claim 3.

5. The plurality of high-composition films further includes a third film. The third film is a third surface region along the intersection direction, a third other surface region along the intersection direction, a third inclined region along the first inclined direction, a third other inclined region along the first other inclined direction, and includes The direction from the third surface region to the third other surface region is along the intersection direction. The position of the third inclined region in the intersection direction is between the position of the third surface region in the intersection direction and the position of the third other surface region in the intersection direction. The position of the third other inclined region in the intersection direction is between the position of the third inclined region in the intersection direction and the position of the third other surface region in the intersection direction. The third inclined portion of the third inclined region is connected to the third surface region. The third other inclined portion of the third other inclined region is connected to the third other surface region. The third connection portion of the third inclined region is connected to the third other inclined region, The position of the third connection portion in the first direction is between the position of the second connection portion in the first direction and the position of the third surface region in the first direction, The third surface region is between the second surface region and the other film, The third other surface region is between the second other surface region and the other film, The third inclined region is between the second inclined region and the other film, The third other inclined region is between the second other inclined region and the other film, The nitride structure according to claim 3, wherein a third distance along the first direction between the third connection portion and the third surface region is shorter than a first distance along the first direction between the first connection portion and the first surface region.

6. The nitride structure according to claim 5, wherein the direction from the first inclined region to the third inclined region is along the first direction.

7. A first intermediate layer provided between the substrate and the laminate and containing Al ｚ１ Ga １－ｚ１ N (0 < z1 < 1) is further provided, The first intermediate layer includes a protruding portion protruding toward the laminate, The nitride structure according to any one of claims 1 to 5, wherein the direction from at least a part of the protruding portion to the first connection portion is along the first direction.

8. The nitride structure according to any one of claims 1 to 5, wherein dislocations passing through the first inclined region merge with dislocations passing through the first other inclined direction.

9. A substrate, A nitride member containing Ga and N, A laminate provided between the substrate and the nitride member in the first direction, Comprising, The laminate, Al ｘ１ Ga １－ｘ１ A plurality of high-composition films containing N(0 < x1 ≤ 1), and Al ｘ２ Ga １－ｘ２ A plurality of low-composition films containing N(0 ≦ x2 < 1, x2 < x1), Including, The high-composition film thickness of one of the plurality of high-composition films in the first direction is thinner than the nitride member thickness of the nitride member in the first direction, The low-composition film thickness of one of the plurality of low-composition films in the first direction is thinner than the nitride member thickness, The high-composition film and the low-composition film are alternately provided along the first direction, The laminate includes a first portion and a second portion, The first portion is provided between the substrate and the second portion, The high-composition film included in the first portion includes a first surface region along an intersection direction intersecting the first direction and a first inclined region along a first inclined direction inclined with respect to the first direction, The high-composition film included in the second portion is along the intersection direction, nitride structure.

10. The nitride structure according to claim 1 or 9, A first electrode, A second electrode, A third electrode, Comprising, The nitride member, Al α１ Ga １－α１ A first semiconductor layer containing N (0 ≦ α1 < 1), Al α２ Ga １－α２ A second semiconductor layer containing N (0 < α2 ≤ 1, α1 < α2), Including, The first semiconductor layer is provided between the laminate and the second semiconductor layer, The second direction from the first electrode to the second electrode intersects the first direction, The position of the third electrode in the second direction is between the position of the first electrode in the second direction and the position of the second electrode in the second direction, The second semiconductor layer includes a first semiconductor portion and a second semiconductor portion, The direction from the first semiconductor portion to the second semiconductor portion is along the second direction, The first electrode is electrically connected to the first semiconductor portion, The second electrode is electrically connected to the second semiconductor portion, a semiconductor device.

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