JP7705811B2 - Semiconductor Device - Google Patents

Description

An embodiment of the present invention relates to a semiconductor device.

For example, there are semiconductor devices that use nitride semiconductors. It is desirable to improve the characteristics of semiconductor devices.

JP 2016-86108 A

Embodiments of the present invention provide a semiconductor device that can improve characteristics.

According to an embodiment of the present invention, a semiconductor device includes a first electrode, a second electrode, a third electrode, a semiconductor member, a first conductive member, a first insulating member, a second insulating member, and a first nitride member. The position of the third electrode in a first direction from the first electrode to the second electrode is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. The semiconductor member includes a first semiconductor region and a second semiconductor region. The first semiconductor region includes Al _x1 Ga _1-x1 N (0≦x1<1). The first semiconductor region includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region. A second direction from the first partial region to the first electrode intersects with the first direction. A direction from the second partial region to the second electrode is along the second direction. A direction from the third partial region to the third electrode is along the second direction. The position of the fourth partial region in the first direction is between the position of the first partial region in the first direction and the position of the third partial region in the first direction. The position of the fifth partial region in the first direction is between the position of the third partial region in the first direction and the position of the second partial region in the first direction. The second semiconductor region includes Al _x2 Ga _1-x2 N (0<x2≦1, x1<x2). The second semiconductor region includes a first semiconductor portion and a second semiconductor portion. A direction from the fourth partial region to the first semiconductor portion is along the second direction. A direction from the fifth partial region to the second semiconductor portion is along the second direction. The second semiconductor portion includes a first portion, a second portion, and a third portion between the first portion and the second portion. The position of the second portion in the first direction is between the position of the first portion in the first direction and the position of the second electrode in the first direction. The first conductive member includes a first conductive region and a second conductive region. The first conductive region overlaps with the third electrode in the second direction. The first portion is between the fifth partial region and a part of the first conductive region. The first conductive member is electrically connected to one of the first electrode and the third electrode. Alternatively, the first conductive member can be electrically connected to the one of the first electrode and the third electrode. The first insulating member includes a first insulating region. The first insulating region is between the third partial region and the third electrode in the second direction. The second insulating member includes a first insulating portion and a second insulating portion. The first insulating portion is between the first portion and the first conductive region in the second direction. The second portion is between the fifth partial region and the second insulating portion. The first nitride member includes Al _x3 Ga _1-x3 N (0≦x3<1) or In _y1 Al _y2 Ga _1-y1-y2 N (0<y1≦1, 0≦y2≦1, y1+y2≦1). The first nitride member includes a first nitride region. The first nitride region is between the first insulating portion and the second insulating portion in the first direction. The first nitride region is between the third portion and the second conductive region in the second direction.

FIG. 1 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. FIG. 2 is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment. FIG. 3 is a schematic cross-sectional view illustrating the semiconductor device according to the second embodiment. FIG. 4 is a schematic cross-sectional view illustrating the semiconductor device according to the second embodiment. FIG. 5 is a schematic cross-sectional view illustrating a semiconductor device according to the third embodiment. FIG. 6 is a schematic cross-sectional view illustrating a semiconductor device according to the third embodiment.

Hereinafter, embodiments 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 compound portion, the size ratio between compound portions, etc. are not necessarily the same as in reality. Even when the same compound portion is shown, the dimensions and ratios of each compound portion may be different depending on the drawing.
In this specification and each drawing, elements similar to those described above with reference to the previous drawings are given the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

First Embodiment
FIG. 1 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment.
As shown in FIG. 1, the semiconductor device 110 according to the embodiment includes a first electrode 51, a second electrode 52, a third electrode 53, a semiconductor member 10M, a first conductive member 61, a first insulating member 41, a second insulating member 42 and a first nitride member 31.

The direction from the first electrode 51 to the second electrode 52 is the first direction. The first direction is the X-axis direction. One direction perpendicular to the X-axis direction is the Z-axis direction. The direction perpendicular to the X-axis and Z-axis directions is the Y-axis direction.

The position of the third electrode 53 in the first direction D1 is between the position of the first electrode 51 in the first direction D1 and the position of the second electrode 52 in the first direction D1. For example, at least a portion of the third electrode 53 is between the first electrode 51 and the second electrode 52 in the first direction D1.

The semiconductor member 10M includes a first semiconductor region 10 and a second semiconductor region 20. In this example, the semiconductor device 110 includes a base body 10s and a nitride semiconductor layer 10B. The nitride semiconductor layer 10B is provided between the base body 10s and the semiconductor member 10M. For example, the nitride semiconductor layer 10B is provided on the base body 10s. The semiconductor member 10M is provided on the nitride semiconductor layer 10B. For example, the first semiconductor region 10 is provided on the nitride semiconductor layer 10B. The second semiconductor region 20 is provided on the first semiconductor region 10. The first to third electrodes 51 to 53 are provided on the semiconductor member 10M. The base body 10s may be, for example, a silicon substrate or a SiC substrate. The nitride semiconductor layer 10B includes, for example, AlGaN.

The first semiconductor region 10 contains Al _x1 Ga _1-x1 N (0≦x1<1). The first semiconductor region 10 is, for example, a GaN layer. The Al composition ratio x1 in the first semiconductor region 10 may be, for example, not less than 0 and not more than 0.1.

For example, the first semiconductor region 10 includes GaN. The first semiconductor region 10 includes a first partial region 11, a second partial region 12, a third partial region 13, a fourth partial region 14, and a fifth partial region 15. A second direction D2 from the first partial region 11 to the first electrode 51 intersects with the first direction D1. The second direction D2 may be, for example, the Z-axis direction.

The direction from the second partial region 12 to the second electrode 52 is along the second direction D2. The direction from the third partial region 13 to the third electrode 53 is along the second direction D2.

The portion of the first semiconductor region 10 that overlaps with the first electrode 51 in the second direction D2 corresponds to the first partial region 11. The portion of the first semiconductor region 10 that overlaps with the second electrode 52 in the second direction D2 corresponds to the second partial region 12. The portion of the first semiconductor region 10 that overlaps with the third electrode 53 in the second direction D2 corresponds to the third partial region 13.

The position of the fourth partial region 14 in the first direction D1 is between the position of the first partial region 11 in the first direction D1 and the position of the third partial region 13 in the first direction D1. The position of the fifth partial region 15 in the first direction D1 is between the position of the third partial region 13 in the first direction D1 and the position of the second partial region 12 in the first direction D1. The first to fifth partial regions 11 to 15 may be continuous with each other. The boundaries between the first to fifth partial regions 11 to 15 may be clear or unclear.

The second semiconductor region 20 includes Al _x2 Ga _1-x2 N (0<x2≦1, x1<x2). The second semiconductor region 20 is, for example, an AlGaN layer. The Al composition ratio x2 in the second semiconductor region 20 may be, for example, not less than 0.25 and not more than 0.4.

The second semiconductor region 20 includes a first semiconductor portion 21 and a second semiconductor portion 22. The direction from the fourth sub-region 14 to the first semiconductor portion 21 is along the second direction D2. The direction from the fifth sub-region 15 to the second semiconductor portion 22 is along the second direction D2. The second semiconductor portion 22 includes a first portion 22a, a second portion 22b, and a third portion 22c. The third portion 22c is between the first portion 22a and the second portion 22b. The position of the second portion 22b in the first direction D1 is between the position of the first portion 22a in the first direction D1 and the position of the second electrode 52 in the first direction D1. The first to third portions 22a to 22c may be continuous with each other. The boundaries between the first to third portions 22a to 22c may be clear or unclear.

For example, the first electrode 51 is electrically connected to the first semiconductor portion 21. For example, the second electrode 52 is electrically connected to the second semiconductor portion 22.

The first conductive member 61 includes a first conductive region 61a and a second conductive region 61b. The first conductive region 61a overlaps with the third electrode 53 in the second direction D2. The second conductive region 61b does not overlap with the third electrode 53 in the second direction D2. The position of the second conductive region 61b in the first direction D1 is between the position of the third electrode 53 in the first direction D1 and the position of the second electrode 52 in the first direction D1. The second conductive region 61b corresponds to a protrusion that protrudes toward the second electrode 52 side with respect to the third electrode 53. The second conductive region 61b corresponds to, for example, a visor portion.

The first portion 22a is between the fifth partial region 15 and a part of the first conductive region 61a in the second direction D2. In this example, the third electrode 53 is between the fifth partial region 15 and the first conductive region 61a in the second direction D2. At least a part of the second portion 22b does not overlap with the first conductive member 61 in the second direction D2.

In the embodiment, the first conductive member 61 is electrically connected to one of the first electrode 51 and the third electrode 53. Alternatively, it may be possible for the first conductive member 61 to be electrically connected to one of the first electrode 51 and the third electrode 53. In the first embodiment, the first conductive member 61 is electrically connected to the first electrode 51. A terminal electrically connected to the first conductive member 61 and a terminal electrically connected to the first electrode 51 may be provided, and these terminals may be electrically connected when the semiconductor device is in use.

For example, the first conductive member 61 includes a first conductive end 61e. The first conductive end 61e is the end on the side of the second electrode 52 in the first direction D1. The position of the first conductive end 61e in the first direction D1 is between the position of the third electrode 53 in the first direction D1 and the position of the second electrode 52 in the first direction D1.

The first insulating member 41 includes a first insulating region 41a. The first insulating region 41a is between the third partial region 13 and the third electrode 53 in the second direction D2.

The second insulating member 42 includes a first insulating portion 42a and a second insulating portion 42b. The first insulating portion 42a is between the first portion 22a and the first conductive region 61a in the second direction D2. The second portion 22b is between the fifth portion region 15 and the second insulating portion 42b.

The first nitride member 31 includes Al _x3 Ga _1-x3 N (0≦x3<1). The first nitride member 31 is, for example, a GaN layer or an AlGaN layer. The Al composition ratio x3 in the first nitride member 31 may be, for example, 0 or more and 0.5 or less. For example, the Al composition ratio x3 in the first nitride member 31 is lower than the Al composition ratio x2 in the second semiconductor region 20 (for example, the second semiconductor portion 22).

The first nitride member 31 includes a first nitride region 31a. The first nitride region 31a is between the first insulating portion 42a and the second insulating portion 42b in the first direction D1. The first nitride region 31a is between the third portion 22c and the second conductive region 61b in the second direction D2. The first nitride region 31a overlaps with the second conductive region 61b in the second direction D2.

The current flowing between the first electrode 51 and the second electrode 52 can be 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. For example, the first electrode 51 functions as a source electrode. The second electrode 52 functions as a drain electrode. The third electrode 53 functions as a gate electrode. The first insulating region 41a functions as a gate insulating film. The semiconductor device 110 is, for example, a transistor. For example, the distance between the first electrode 51 and the third electrode 53 is shorter than the distance between the third electrode 53 and the second electrode 52.

A carrier region 10C is formed in a portion of the first semiconductor region 10 facing the second semiconductor region 20. The carrier region 10C is, for example, a two-dimensional electron gas. The semiconductor device 110 is, for example, a high electron mobility transistor (HEMT).

The first conductive member 61 functions, for example, as a field plate. As described above, in the embodiment, the first conductive member 61 is provided with a second conductive region 61b (protrusion or eaves). A first nitride region 31a (GaN or AlGaN) is provided in a portion overlapping with the second conductive region 61b. This locally reduces the carrier concentration of the carrier region 10C in the region overlapping with the second conductive region 61b.

In general, an electric field concentrates at the end (first conductive end 61e) of the second conductive region 61b (protrusion or eaves). This concentration of the electric field tends to reduce the breakdown voltage. In the embodiment, the carrier concentration can be locally reduced in the region overlapping with the second conductive region 61b. This makes it easier to obtain a high breakdown voltage. According to the embodiment, a semiconductor device with improved characteristics can be provided.

In this example, the first nitride member 31 includes a second nitride region 31b and a third nitride region 31c. The first insulating portion 42a is between the first portion 22a and the second nitride region 31b. The second insulating portion 42b is between the second portion 22b and the third nitride region 31c. The first nitride region 31a, the second nitride region 31b, and the third nitride region 31c may be continuous with each other. The boundaries between the first nitride region 31a, the second nitride region 31b, and the third nitride region 31c may be clear or unclear. The first nitride member 31 is easily formed by providing the first nitride region 31a, the second nitride region 31b, and the third nitride region 31c continuously.

In the first nitride member 31, the portion that overlaps with the second conductive region 61b in the second direction D2 corresponds to the first nitride region 31a. In the first nitride member 31, the portion between the first insulating portion 42a and the second insulating portion 42b in the first direction D1 corresponds to the first nitride region 31a. In this example, the first nitride region 31a contacts the third portion 22c. As described later, another layer (e.g., an AlN layer) may be provided between the first nitride region 31a and the third portion 22c.

For example, the crystallinity of the first nitride region 31a may be higher than the crystallinity of the second nitride region 31b and higher than the crystallinity of the third nitride region 31c. At least a portion of the first nitride region 31a may contain crystals. At least a portion of the second nitride region 31b may be amorphous. At least a portion of the third nitride region 31c may be amorphous.

The thickness t1 of the first nitride region 31a along the second direction D2 is, for example, 1 nm or more and 10 nm or less. When the thickness t1 is 1 nm or more, for example, a homogeneous first nitride region 31a is easily obtained. When the thickness t1 is 10 nm or less, for example, crystal defects such as misfit dislocations caused by film stress are easily suppressed. The thickness t1 may be 3 nm or more and 5 nm or less. When the thickness t1 is 3 nm or more, for example, a homogeneous first nitride region 31a is more easily obtained. When the thickness t1 is 3 nm or more, for example, the carrier concentration is easily controlled stably. When the thickness t1 is 5 nm or less, for example, crystal defects such as misfit dislocations caused by film stress are more easily suppressed.

In the embodiment, the second insulating member 42 contains silicon and nitrogen. The second insulating member 42 contains, for example, SiN. Such a second insulating member 42 makes it easier to obtain high quality in the semiconductor member 10M below the second insulating member 42.

For example, the first insulating member 41 contains silicon and oxygen. The first insulating member 41 contains, for example, silicon oxide (SiO ₂ ). For example, the first insulating member 41 does not substantially contain nitrogen. Or, the concentration of nitrogen in the first insulating member 41 is lower than the concentration of nitrogen in the second insulating member 42. With such a first insulating member 41, for example, a stable threshold voltage can be easily obtained.

1, the first insulating member 41 may further include a second insulating region 41b and a third insulating region 41c. The second insulating region 41b is between the first semiconductor portion 21 and the third electrode 53 in the first direction D1. The third insulating region 41c is between the third electrode 53 and the second semiconductor portion 22 in the first direction D1. At least a portion of the third electrode 53 is between the first semiconductor portion 21 and the second semiconductor portion 22 in the first direction D1.

At least a portion of the first insulating region 41a is between the fourth partial region 14 and the fifth partial region 15 in the first direction D1. For example, a recess is provided in the semiconductor member 10M, and at least a portion of the third electrode 53 is embedded in the recess. The semiconductor device 110 is a gate recess type transistor.

As shown in FIG. 1, the second insulating member 42 may include a third insulating portion 42c. The first semiconductor portion 21 is between the fourth portion region 14 and the third insulating portion 42c.

As shown in FIG. 1, the first insulating member 41 further includes a fourth insulating region 41d. At least a portion of the fourth insulating region 41d is between the third electrode 53 and the first conductive member 61.

The first insulating member 41 may include a fifth insulating region 41e and a sixth insulating region 41f. The first semiconductor portion 21 is between the fourth partial region 14 and the fifth insulating region 41e. The second semiconductor portion 22 is between the fifth partial region 15 and the sixth insulating region 41f.

As shown in FIG. 1, the length of the first nitride region 31a along the first direction D1 is defined as the first length w1. The second semiconductor portion 22 includes an end 22p on the side of the third electrode 53. The second semiconductor portion 22 includes a portion 22q that overlaps with the second electrode 52 in the second direction D2. The distance in the first direction D1 between the end 22p of the second semiconductor portion 22 on the side of the third electrode 53 and the position of the portion 22q of the second semiconductor portion 22 that overlaps with the second electrode 52 in the second direction D2 is defined as the second length w2. The first length w1 is, for example, 0.035 times or more and 0.5 times or less of the second length. With such a first length w1, for example, a region with a controlled carrier concentration is appropriately formed, making it easy to effectively obtain a high breakdown voltage.

FIG. 2 is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.
2 , the semiconductor device 111 according to the embodiment includes a second nitride member 32. The configuration of the semiconductor device 111 other than this is the same as the configuration of the semiconductor device 110. For example, in the semiconductor device 111, the configurations of the first electrode 51, the second electrode 52, the third electrode 53, the semiconductor member 10M, the first conductive member 61, the first insulating member 41, the second insulating member 42, and the first nitride member 31 may be the same as those of the semiconductor device 110.

The second nitride member 32 includes Al _x4 Ga _1-x4 N (0<x4≦1, x3<x4). The second nitride member 32 may be, for example, an AlN layer. The Al composition ratio x4 in the second nitride member 32 may be, for example, 0.5 or more and 1.0 or less.

At least a portion of the second nitride member 32 is between the first portion 22a and the first insulating portion 42a, and between the second portion 22b and the second insulating portion 42b. A portion of the second nitride member 32 may be provided between the third portion 22c and the first nitride region 31a.

By providing the second nitride member 32 as described above, high quality can be obtained in the second semiconductor portion 22. For example, damage to the second semiconductor portion 22 caused by the second insulating member 42 can be suppressed.

In the semiconductor device 111, the carrier concentration can be locally reduced in the region overlapping with the second conductive region 61b. A high breakdown voltage can be easily obtained. A semiconductor device with improved characteristics can be provided.

For example, the second nitride member 32 may be in contact with the third portion 22c and the first nitride region 31a.

As shown in FIG. 2, a portion of the second nitride member 32 may be provided between the first semiconductor portion 21 and the third insulating portion 42c. For example, damage to the second semiconductor portion 22 caused by the second insulating member 42 can be suppressed.

The thickness t2 of the second nitride member 32 along the second direction D2 is, for example, 1 nm or more and 10 nm or less. When the thickness t2 is 1 nm or more, for example, damage to the second semiconductor region 20 can be effectively suppressed. When the thickness t2 is 10 nm or less, for example, crystal defects such as misfit dislocations due to film stress can be easily suppressed in the second nitride member 32. The thickness t2 may be, for example, 3 nm or more and 5 nm or less. When the thickness t2 is 3 nm or more, damage to the second semiconductor region 20 can be more effectively suppressed. When the thickness t2 is 5 nm or less, for example, crystal defects such as misfit dislocations due to film stress can be more easily suppressed.

Second Embodiment
FIG. 3 is a schematic cross-sectional view illustrating the semiconductor device according to the second embodiment.
3 , in the semiconductor device 112 according to the embodiment, the first conductive member 61 is electrically connected to the third electrode 53. Except for this, the configuration of the semiconductor device 112 is the same as the configuration of the semiconductor device 110. For example, in the semiconductor device 112, the configurations of the first electrode 51, the second electrode 52, the third electrode 53, the semiconductor member 10M, the first insulating member 41, the second insulating member 42, and the first nitride member 31 may be the same as those of the semiconductor device 110.

In the semiconductor device 112, a terminal electrically connected to the first conductive member 61 and a terminal electrically connected to the third electrode 53 are provided, and these terminals may be electrically connected when the semiconductor device is in use.

The first nitride region 31a is also provided in the semiconductor device 112. The first nitride region 31a is between the first insulating portion 42a and the second insulating portion 42b in the first direction D1. The first nitride region 31a is between the third portion 22c and the second conductive region 61b in the second direction D2. The first nitride region 31a overlaps with the second conductive region 61b in the second direction D2.

As a result, the carrier concentration of the carrier region 10C is locally reduced in the region overlapping with the second conductive region 61b. This makes it easier to obtain a high breakdown voltage. According to the embodiment, a semiconductor device with improved characteristics can be provided.

FIG. 4 is a schematic cross-sectional view illustrating the semiconductor device according to the second embodiment.
4 , the semiconductor device 113 according to the embodiment includes a second nitride member 32. The configuration of the semiconductor device 113 other than this is similar to the configuration of the semiconductor device 112. For example, in the semiconductor device 113, the configurations of the first electrode 51, the second electrode 52, the third electrode 53, the semiconductor member 10M, the first conductive member 61, the first insulating member 41, the second insulating member 42, and the first nitride member 31 may be similar to those of the semiconductor device 112.

In the semiconductor device 113, the carrier concentration can be locally reduced in the region overlapping with the second conductive region 61b. A high breakdown voltage can be easily obtained. A semiconductor device with improved characteristics can be provided.

In an embodiment, information regarding crystallinity is obtained, for example, from an X-ray diffraction pattern image. Information regarding composition ratio is obtained, for example, from X-ray photoelectron spectroscopy.

In the semiconductor devices 110 to 113 according to the embodiment, the first nitride member 31 may contain In, Ga, and nitrogen. For example, the first nitride member 31 may contain Al _x3 Ga _1-x3 N (0≦x3<1), or In _y1 Al _y2 Ga _1-y1-y2 N (0<y1≦1, 0≦y2≦1, y1+y2≦1). For example, the first nitride member 31 may contain In _y1 Ga _1-y1 N (0<y1≦1). On the other hand, the second nitride member 32 contains Al _x4 Ga _1-x4 N (0<x4≦1, x3<x4). For example, the first nitride member 31 contains InGaN, and the second nitride member 32 contains AlGaN or AlN.

Third Embodiment
FIG. 5 is a schematic cross-sectional view illustrating a semiconductor device according to the third embodiment.
5, in the semiconductor device 121, the first nitride member 31 includes fourth to seventh nitride regions 31d to 31g in addition to the first to third nitride regions 31a to 31c. The second nitride member 32 includes first to seventh nitride portions 32a to 32g.

The first nitride portion 32a is between the third portion 22c and the first nitride region 31a. The second nitride portion 32b is between the first portion 22a and the second nitride region 31b. The third nitride portion 32c is between the second portion 22b and the third nitride region 31c.

The fourth nitride region 31d is between the third partial region 13 and the third electrode 53 in the second direction D2. The fourth nitride region 31d is between the first insulating region 41a and the third electrode 53 in the second direction D2. The fifth nitride region 31e is, for example, between the first semiconductor portion 21 and at least a part of the third electrode 53 in the first direction D1. The fifth nitride region 31e is, for example, between the first semiconductor portion 21 and at least a part of the second insulating region 41b in the first direction D1. The sixth nitride region 31f is, for example, between at least a part of the third electrode 53 and the first portion 22a in the first direction D1. The sixth nitride region 31f is, for example, between at least a part of the third insulating region 41c and the first portion 22a in the first direction D1.

The fourth nitride portion 32d is between the third portion region 13 and the fourth nitride region 31d in the second direction D2. The fifth nitride portion 32e is between the first semiconductor portion 21 and the fifth nitride region 31e in the second direction D2. The sixth nitride portion 32f is between the sixth nitride region 31f and the first portion 22a in the second direction D2.

The first semiconductor portion 21 is located between the fourth portion region 14 and the seventh nitride region 31g in the second direction D2. The third insulating portion 42c is located between the seventh nitride portion 32g and the seventh nitride region 31g in the second direction D2.

Other than the above, the configuration of the semiconductor device 121 may be the same as that of the semiconductor device 111. By providing the first nitride member 31 and the second nitride member 32 as described above, for example, a lower subthreshold swing is easily obtained.

FIG. 6 is a schematic cross-sectional view illustrating a semiconductor device according to the third embodiment.
6, in the semiconductor device 122, the first nitride member 31 includes first to seventh nitride regions 31a to 31g. The second nitride member 32 includes first to seventh nitride portions 32a to 32g. The configuration of the semiconductor device 122 other than the above may be similar to that of the semiconductor device 112. By providing the first nitride member 31 and the second nitride member 32 as described above, for example, a lower subthreshold swing is easily obtained.

In the semiconductor devices 112 and 122 , for example , the first nitride member 31 may include Al _x3 Ga _1-x3 N (0≦x3<1) or In _y1 Al _y2 Ga _1-y1-y2 N (0<y1≦1, 0≦y2≦1, y1+y2≦1). For example, the first nitride member 31 may include In _y1 Ga _1-y1 N (0<y1≦1). On the other hand, the second nitride member 32 includes Al _x4 Ga _1-x4 N (0<x4≦1, x3<x4). For example, the first nitride member 31 includes InGaN, and the second nitride member 32 includes AlGaN or AlN.

According to the embodiment, a semiconductor device with improved characteristics can be provided.

In the embodiments, the term " _nitride semiconductor" includes all semiconductors having _compositions in which the composition ratios x, y, and z are changed within the respective ranges in the chemical formula _{BxInyAlzGa1 -x-y-zN} (0≦x≦1, 0≦y≦1, 0≦z≦1, x+y+z≦1). In the above chemical formula, the term "nitride semiconductor" also includes those that further include a Group V element other than N (nitrogen), those that further include various elements added to control various physical properties such as the conductivity type, and those that further include various elements that are unintentionally included.

In this specification, "vertical" and "parallel" do not only mean strictly vertical and strictly parallel, but also include, for example, variations in the manufacturing process, and may mean substantially vertical and substantially parallel.

The above describes the embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of each element included in a semiconductor device, such as electrodes, semiconductor members, compound members, nitride members, and insulating members, are included within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting from the known range.

In addition, any combination of two or more elements of each specific example, within the scope of technical feasibility, is also included in the scope of the present invention as long as it includes the gist of the present invention.

In addition, all semiconductor devices that can be implemented by a person skilled in the art through appropriate design modifications based on the semiconductor device described above as an embodiment of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention.

In addition, within the scope of the concept of this invention, a person skilled in the art may conceive of various modifications and alterations, and these modifications and alterations are also considered to fall within the scope of this invention.

Although several 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 embodied in various other forms, and various omissions, substitutions, and modifications 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 scope of the invention and its equivalents described in the claims.

10...first semiconductor region, 10B...nitride semiconductor layer, 10C...carrier region, 10M...semiconductor member, 10s...base, 11-15...first to fifth partial regions, 20...second semiconductor region, 21, 22...first and second semiconductor portions, 22a-22c...first to third portions, 22p...edge, 22q...portion, 31...first nitride member, 31a-31g...first to seventh nitride regions, 32...second nitride member, 32a-32g...first to seventh nitride portions, 41...first insulating member, 41a-41f...first to sixth insulating regions, 42...second insulating member, 42a-42c...first to third insulating portions, 51-53...first to third electrodes, 61...first conductive member, 61a, 61b...first and second conductive regions; 61e...first conductive end; 110-113, 121, 122...semiconductor device; D1, D2...first and second directions; t1, t2...thickness; w1, w2...first and second lengths

Claims (20)

A first electrode;
A second electrode;
a third electrode, the position of the third electrode in a first direction from the first electrode to the second electrode being between the position of the first electrode in the first direction and the position of the second electrode in the first direction;
A semiconductor member including a first semiconductor region and a second semiconductor region,
the first semiconductor region includes Al _x1 Ga _1-x1 N (0≦x1<1), the first semiconductor region includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, a second direction from the first partial region to the first electrode intersects with the first direction, a direction from the second partial region to the second electrode is along the second direction, a direction from the third partial region to the third electrode is along the second direction, a position of the fourth partial region in the first direction is between a position of the first partial region in the first direction and a position of the third partial region in the first direction, and a position of the fifth partial region in the first direction is between the position of the third partial region in the first direction and a position of the second partial region in the first direction,
The second semiconductor region includes Al _x2 Ga _1-x2 N (0<x2≦1, x1<x2), the second semiconductor region includes a first semiconductor portion and a second semiconductor portion, a direction from the fourth partial region to the first semiconductor portion is along the second direction, a direction from the fifth partial region to the second semiconductor portion is along the second direction, the second semiconductor portion includes a first portion, a second portion, and a third portion between the first portion and the second portion, and a position of the second portion in the first direction is between a position of the first portion in the first direction and the position of the second electrode in the first direction. The semiconductor member;
a first conductive member including a first conductive region and a second conductive region, the first conductive region overlapping the third electrode in the second direction, the first portion being between the fifth portion region and a part of the first conductive region, the first conductive member being electrically connected to one of the first electrode and the third electrode, or the first conductive member being capable of being electrically connected to the one of the first electrode and the third electrode;
a first insulating member including a first insulating region, the first insulating region being between the third partial region and the third electrode in the second direction;
a second insulating member including a first insulating portion and a second insulating portion, the first insulating portion being between the first portion and the first conductive region in the second direction, and the second portion being between the fifth portion region and the second insulating portion;
A first nitride member including Al _x3 Ga _1-x3 N (0≦x3<1) or In _y1 Al _y2 Ga _1-y1-y2 N (0<y1≦1, 0≦y2≦1, y1+y2≦1), the first nitride member including a first nitride region, the first nitride region being between the first insulating portion and the second insulating portion in the first direction, and the first nitride region being between the third portion and the second conductive region in the second direction;
Equipped with
the first nitride member includes a second nitride region and a third nitride region;
the first insulating portion is between the first portion and the second nitride region;
the second insulating portion is between the second portion and the third nitride region . The semiconductor device according to claim 1, wherein at least a portion of the second insulating portion does not overlap with the first conductive member in the second direction. 2. The semiconductor device according to claim 1 , wherein the first nitride region has a higher crystallinity than the second nitride region and a higher crystallinity than the third nitride region. At least a portion of the first nitride region comprises a crystal;
At least a portion of the second nitride region is amorphous;
The semiconductor device of claim 1 , wherein at least a portion of said third nitride region is amorphous. 5. The semiconductor device according to claim 1, wherein said first nitride region is in contact with said third portion. A second nitride member including Al _x4 Ga _1-x4 N (0<x4≦1, x3<x4);
5. The semiconductor device according to claim 1 , wherein at least a portion of the second nitride member is between the first portion and the first insulating portion, and between the second portion and the second insulating portion. The semiconductor device of claim 6 , wherein a portion of said second nitride member is between said third portion and said first nitride region. The semiconductor device according to claim 6 , wherein the second nitride member is in contact with the third portion and the first nitride region. The semiconductor device according to claim 6 , wherein the second nitride member has a thickness along the second direction of not less than 1 nm and not more than 10 nm. 10. The semiconductor device according to claim 1 , wherein said x3 is lower than said x2. 10. The semiconductor device according to claim 1, wherein the first nitride region has a thickness along the second direction of not less than 1 nm and not more than 10 nm. 13. The semiconductor device according to claim 1 , wherein the second insulating member contains silicon and nitrogen. the first insulating member includes silicon and oxygen;
The semiconductor device according to claim 12 , wherein the first insulating member does not contain nitrogen, or the concentration of nitrogen in the first insulating member is lower than the concentration of nitrogen in the second insulating member. The first insulating member further includes a second insulating region and a third insulating region,
the second insulating region is between the first semiconductor portion and the third electrode in the first direction;
14. The semiconductor device according to claim 1, wherein the third insulating region is between the third electrode and the second semiconductor portion in the first direction. The first insulating member further includes a fourth insulating region,
15. The semiconductor device according to claim 1 , wherein at least a portion of said fourth insulating region is between said third electrode and said first conductive member. A first electrode;
A second electrode;
a third electrode, the position of the third electrode in a first direction from the first electrode to the second electrode being between the position of the first electrode in the first direction and the position of the second electrode in the first direction;
A semiconductor member including a first semiconductor region and a second semiconductor region,
the first semiconductor region includes Al _x1 Ga _1-x1 N (0≦x1<1), the first semiconductor region includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, a second direction from the first partial region to the first electrode intersects with the first direction, a direction from the second partial region to the second electrode is along the second direction, a direction from the third partial region to the third electrode is along the second direction, a position of the fourth partial region in the first direction is between a position of the first partial region in the first direction and a position of the third partial region in the first direction, and a position of the fifth partial region in the first direction is between the position of the third partial region in the first direction and a position of the second partial region in the first direction,
The second semiconductor region includes Al _x2 Ga _1-x2 N (0<x2≦1, x1<x2), the second semiconductor region includes a first semiconductor portion and a second semiconductor portion, a direction from the fourth partial region to the first semiconductor portion is along the second direction, a direction from the fifth partial region to the second semiconductor portion is along the second direction, the second semiconductor portion includes a first portion, a second portion, and a third portion between the first portion and the second portion, and a position of the second portion in the first direction is between a position of the first portion in the first direction and the position of the second electrode in the first direction. The semiconductor member;
a first conductive member including a first conductive region and a second conductive region, the first conductive region overlapping the third electrode in the second direction, the first portion being between the fifth portion region and a part of the first conductive region, the first conductive member being electrically connected to one of the first electrode and the third electrode, or the first conductive member being capable of being electrically connected to the one of the first electrode and the third electrode;
a first insulating member including a first insulating region, the first insulating region being between the third partial region and the third electrode in the second direction;
a second insulating member including a first insulating portion and a second insulating portion, the first insulating portion being between the first portion and the first conductive region in the second direction, and the second portion being between the fifth portion region and the second insulating portion;
A first nitride member including Al _x3 Ga _1-x3 N (0≦x3<1) or In _y1 Al _y2 Ga _1-y1-y2 N (0<y1≦1, 0≦y2≦1, y1+y2≦1), the first nitride member including a first nitride region, the first nitride region being between the first insulating portion and the second insulating portion in the first direction, and the first nitride region being between the third portion and the second conductive region in the second direction;
Equipped with
The first insulating member further includes a fourth insulating region,
At least a portion of the fourth insulating region is between the third electrode and the first conductive member . The semiconductor device according to any one of claims 1 to 16, wherein at least a portion of the first insulating region is between the fourth partial region and the fifth partial region in the first direction. The semiconductor device according to any one of claims 1 to 17, wherein at least a portion of the third electrode is between the first semiconductor portion and the second semiconductor portion in the first direction. The semiconductor device according to any one of claims 1 to 18, wherein a distance along the first direction between the first electrode and the third electrode is shorter than a distance along the first direction between the third electrode and the second electrode. a first length of the first nitride region along the first direction is 0.035 times or more and 0.5 times or less than a second length;
A semiconductor device according to any one of claims 1 to 19, wherein the second length is the distance in the first direction between the end of the second semiconductor portion on the side of the third electrode and the position of the portion of the second semiconductor portion that overlaps with the second electrode in the second direction.

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