Semiconductor equipment

Abstract

To provide a semiconductor device that can improve characteristics.SOLUTION: According to an embodiment, a semiconductor device includes first to third electrodes and first to third nitride regions. The first nitride region includes Alx1Ga1-x1 N (0≤x1<1). The second nitride region includes Alx2Ga1-x2 N (x1<x2≤1) or InyAlzGa(1-y-z)N (0<y≤1, 0≤z<1, y+z≤1). The third nitride region includes Alx3Ga1-x3 N (x1<x3<x2). The third nitride region includes a seventh partial region. The seventh partial region is between the third partial region of the first nitride region and the third electrode.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] For example, improvements in the characteristics of semiconductor devices such as transistors are desired. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-53585 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Embodiments of the present invention provide a semiconductor device capable of improving its characteristics. [Means for solving the problem]

[0005] According to embodiments of the present invention, the semiconductor device includes a first electrode, a second electrode, a third electrode, a first nitride region, a second nitride region, and a third nitride region. The direction from the first electrode to the second electrode is along the first direction. The position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. The first nitride region is Al x1 Ga 1-x1It includes N(0≦x1<1). The first nitride region includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region. The direction from the first partial region to the first electrode is along a second direction that intersects the first direction. The direction from the second partial region to the second electrode is along the second direction. The 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 nitride region is Al x2 Ga 1-x2 N(x1<x2≦1) or In y Al z Ga (1-y-z) It includes N(0<y≦1, 0≦z<1, y + z≦1). The second nitride region includes a sixth partial region. The direction from the fourth partial region to the sixth partial region is along the second direction. The third nitride region is Al x3 Ga 1-x3 It includes N(x1<x3<x2). The third nitride region includes a seventh partial region. The seventh partial region is between the third partial region and the third electrode.

Brief Description of the Drawings

[0006] [Figure 1] FIG. 1 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. [Figure 4] FIG. 4 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. [Figure 6]FIG. 6 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. [Figure 7] FIG. 7 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. [Figure 8] FIG. 8 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. [Figure 9] FIGS. 9(a) to 9(d) are schematic cross-sectional views illustrating a method of manufacturing a semiconductor device according to an embodiment. [Figure 10] FIGS. 10(a) to 10(c) are schematic cross-sectional views illustrating a method of manufacturing a semiconductor device according to an embodiment.

MODE 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 already shown figures, and the detailed description will be omitted as appropriate.

[0008] (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 first nitride region 11, a second nitride region 12, and a third nitride region 13.

[0009] The direction from the first electrode 51 to the second electrode 52 is along the first direction D1. The first direction D1 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 direction and the Z-axis direction is the Y-axis direction.

[0010] 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. In the first direction D1, at least a portion of the third electrode 53 may be between at least a portion of the first electrode 51 and at least a portion of the second electrode 52.

[0011] The first nitride region 11 is Al x1 Ga 1-x1 N includes (0 ≤ x1 < 1). In one example, the composition ratio x1 of Al in the first nitride region 11 is, for example, 0 or greater and less than 0.1. The first nitride region 11 includes, for example, GaN. The first nitride region 11 includes crystals.

[0012] The first nitride region 11 includes a first subregion 11a, a second subregion 11b, a third subregion 11c, a fourth subregion 11d, and a fifth subregion 11e. The direction from the first subregion 11a to the first electrode 51 is along the second direction D2. The second direction D2 intersects the first direction D1. The second direction D2 is, for example, the Z-axis direction.

[0013] The direction from the second subregion 11b to the second electrode 52 follows the second direction D2. The direction from the third subregion 11c to the third electrode 53 follows the second direction D2. For example, the region overlapping with the first electrode 51 in the second direction D2 corresponds to the first subregion 11a. For example, the region overlapping with the second electrode 52 in the second direction D2 corresponds to the second subregion 11b. For example, the region overlapping with the third electrode 53 in the second direction D2 corresponds to the third subregion 11c.

[0014] The position of the fourth subregion 11d in the first direction D1 lies between the position of the first subregion 11a in the first direction D1 and the position of the third subregion 11c in the first direction D1. The position of the fifth subregion 11e in the first direction D1 lies between the position of the third subregion 11c in the first direction D1 and the position of the second subregion 11b in the first direction D1. The boundaries between these subregions may be unclear or clear.

[0015] The second nitride region 12 contains Al x2 Ga 1-x2 N (x1 < x2 ≤ 1) or In y Al z Ga (1-y-z) N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1). When the second nitride region 12 contains Al x2 Ga 1-x2 N (x1 < x2 ≤ 1), the composition ratio x2 of Al is, for example, 0.8 or more and 1 or less. In one example, the second nitride region 12 may contain AlN. Alternatively, the second nitride region 12 may contain InAlGaN. Hereinafter, an example in which the second nitride region 12 contains Al x2 Ga 1-x2 N (x1 < x2 ≤ 1) will be described. The second nitride region 12 contains crystals. As will be described later, a part of the second nitride region 12 may be amorphous.

[0016] The second nitride region 12 includes a sixth sub-region 12f. The direction from the fourth sub-region 11d to the sixth sub-region 12f is along the second direction D2.

[0017] The third nitride region 13 contains Al x3 Ga 1-x3 N (x1 < x3 < x2). The composition ratio x3 of Al in the third nitride region 13 is, for example, 0.1 or more and 0.35 or less. The third nitride region 13 contains crystals.

[0018] The third nitride region 13 includes a seventh sub-region 13g. The seventh sub-region 13g is between the third sub-region 11c and the third electrode 53.

[0019] In the example shown in FIG. 1, the semiconductor device 110 includes a first insulating member 41. The first insulating member 41 includes a first insulating region 41a. The first insulating region 41a is between the third sub-region 11c and the third electrode 53.

[0020] 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 reference to the potential of the first electrode 51. The first electrode 51 functions, for example, as a source electrode. The second electrode 52 functions, for example, as a drain electrode. The third electrode 53 functions as a gate electrode. The semiconductor device 110 is, for example, a transistor.

[0021] The first nitride region 11 includes a region facing the second nitride region 12 and a region facing the third nitride region 13. For example, a carrier region 10c is formed in these regions. The carrier region 10c is, for example, a two-dimensional electron gas. The semiconductor device is, for example, a HEMT (High Electron Mobility Transistor).

[0022] The distance along the first direction D1 between the first electrode 51 and the third electrode 53 is shorter than the distance along the first direction D1 between the third electrode 53 and the second electrode 52. For example, a high voltage is applied to the second electrode 52. A longer distance along the first direction D1 between the third electrode 53 and the second electrode 52 makes it easier to obtain stable characteristics, for example. Damage can be suppressed.

[0023] In this embodiment, a high Al composition ratio is applied in the sixth subregion 12f (second nitride region 12). This results in a high carrier concentration in the portion corresponding to the sixth subregion 12f. This leads to a low sheet resistance. For example, a low on-resistance is obtained.

[0024] On the other hand, a low Al composition ratio is applied in the seventh subregion 13g. A low Al composition ratio makes it easier to obtain high crystal quality in the seventh subregion 13g. This, for example, makes it easier to obtain high gate reliability and reduces gate leakage current.

[0025] In the operation of the semiconductor device 110, the electric field strength applied between the first electrode 51 and the third electrode 53 is relatively low. Therefore, in the sixth partial region 12f (second nitride region 12) to which a high Al composition ratio is applied, the crystal quality does not necessarily have to be high. Since the electric field strength is low, practically sufficient stable characteristics can be obtained even with low crystal quality. As described above, in the sixth partial region 12f, by applying a high Al composition ratio, a high carrier concentration can be obtained, and thereby a low on-resistance can be obtained.

[0026] In the embodiment, by applying a high Al composition ratio to the sixth partial region 12f, a low on-resistance can be obtained. On the other hand, by applying a low Al composition ratio to the seventh partial region 13g, high gate reliability can be obtained. According to the embodiment, a semiconductor device capable of improving characteristics can be provided. According to the embodiment, high reliability can be maintained.

[0027] As shown in FIG. 1, the sixth partial region 12f has a first thickness t1 along the second direction D2. The seventh partial region 13g has a second thickness t2 along the second direction D2. In the embodiment, it is preferable that the first thickness t1 is thinner than the second thickness t2. When the thickness is large when the Al composition ratio is high, the crystal quality tends to deteriorate rapidly. For example, cracks are likely to occur in the crystal. For example, the gate leakage current tends to increase. By making the first thickness t1 of the sixth partial region 12f with a high Al composition ratio thin, high crystal quality can be maintained.

[0028] When the second nitride region 12 contains In y Al z Ga (1-y-z) N (0 < y ≦ 1, 0 ≦ z < 1, y + z ≦ 1), a high carrier concentration can be obtained in the portion corresponding to the sixth partial region 12f. Thereby, a low sheet resistance can be obtained. For example, a low on-resistance can be obtained. The composition ratio y of In is preferably, for example, more than 0 and 0.2 or less. The composition ratio z of Al is preferably, for example, 0.8 or more and less than 1.

[0029] For example, the first thickness t1 is preferably 0.5 times or less the second thickness t2. For example, the first thickness t1 is preferably 1 nm or more and 10 nm or less. For example, the second thickness t2 is preferably 20 nm or more and 40 nm or less. A practical nitride region with high crystal quality can be obtained.

[0030] As shown in Figure 1, the third nitride region 13 may further include the eighth subregion 13h. The direction from the fifth subregion 11e to the eighth subregion 13h is along the second direction D2. During the operation of the semiconductor device 110, a high voltage is applied to the second electrode 52. The potential difference between the third electrode 53 and the second electrode 52 is large. In the region between the third electrode 53 and the second electrode 52, the third nitride region 13 (eighth subregion 13h), which has a low Al composition ratio and easily yields high crystal quality, is applied. This makes it easier to obtain high operational stability. For example, high reliability is easily obtained. The breakdown voltage of the semiconductor device is improved.

[0031] As shown in Figure 1, the eighth subregion 13h has a third thickness t3 along the second direction D2. The first thickness t1 is thinner than the third thickness t3. The third thickness t3 may be substantially the same as the second thickness t2.

[0032] The first electrode 51 is electrically connected to at least one of the first subregion 11a and the sixth subregion 12f. The second electrode 52 is electrically connected to at least one of the second subregion 11b and the eighth subregion 13h.

[0033] As shown in Figure 1, the sixth partial region 12f may be located between the fourth partial region 11d and a part of the first insulating member 41. For example, a part of the first insulating member 41 may be provided on the sixth partial region 12f. The part of the first insulating member 41 functions, for example, as a protective film. For example, the sixth partial region 12f becomes stable. The part of the first insulating member 41 functions, for example, as a gate insulating film. For example, a stable threshold voltage can be obtained. For example, the gate leakage current can be reduced.

[0034] The first insulating member 41 may include, for example, at least one selected from the group consisting of SiN, SiO2, SiON, AlN, AlON, AlSiON, and Al2O3.

[0035] As shown in Figure 1, the first electrode 51 includes a first electrode surface 51f. The direction from the first partial region 11a to the first electrode surface 51f is along the second direction D2. For example, the first electrode surface 51f faces the first partial region 11a. The second electrode 52 includes a second electrode surface 52f. The direction from the second partial region 11b to the second electrode surface 52f is along the second direction D2. For example, the second electrode surface 52f faces the second partial region 11b. For example, the second electrode surface 52f may face the third nitride region 13 (eighth partial region 13h).

[0036] The height of the first electrode surface 51f may differ from the height of the second electrode surface 52f. A "step" may be provided between these electrodes. For example, the position of the first electrode surface 51f in the second direction D2 may differ from the position of the second electrode surface 52f in the second direction D2. The difference between these positions does not need to be excessively large.

[0037] For example, the distance in the second direction D2 between the position of the first electrode surface 51f in the second direction D2 and the position of the second electrode surface 52f in the second direction D2 is preferably 50 nm or less.

[0038] The semiconductor device 110 has, for example, normally-on characteristics. The first electrode 51, the second electrode 52, and the third electrode 53 may extend along the Y-axis.

[0039] As shown in Figure 1, the semiconductor device 110 may include a substrate 18s. The semiconductor device 110 may include a nitride layer 18b. The substrate 18s may include at least one selected from the group consisting of, for example, silicon, GaN, and SiC. The nitride layer 18b is provided on the substrate 18s. The nitride layer 18b includes, for example, Al, Ga, and N. The nitride layer 18b is, for example, a buffer layer. A semiconductor member 10M is provided on the buffer layer. The semiconductor member 10M includes a first nitride region 11, a second nitride region 12, and a third nitride region 13. The semiconductor member 10M is formed, for example, by epitaxial growth.

[0040] In one example, the sixth subregion 12f is an AlN film with a thickness of 3 nm. In this case, the carrier concentration in the region between the first electrode 51 and the third electrode 53 is approximately 7 × 10⁻⁶. 12 cm -2 Therefore, the sheet resistance in the region between the first electrode 51 and the third electrode 53 is 540 Ω / square.

[0041] On the other hand, in the reference example, the sixth subregion 12f is made of Al with a thickness of 30 nm. 0.17 Ga 0.83 This is an N film. In this case, the carrier concentration in the region between the first electrode 51 and the third electrode 53 is approximately 5.5 × 10⁻⁶. 12 cm -2 Therefore, the sheet resistance in the region between the first electrode 51 and the third electrode 53 is 630 Ω / square.

[0042] Thus, by applying a high Al composition ratio to the sixth subregion 12f, a high carrier concentration can be obtained, resulting in a low sheet resistance.

[0043] Figure 2 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. As shown in Figure 2, in the semiconductor device 111 according to this embodiment, the shape of the second nitride region 12 is different from the shape of the second nitride region 12 in the semiconductor device 110. The configuration of the semiconductor device 111, excluding this, may be the same as that of the semiconductor device 110.

[0044] In the semiconductor device 111, the second nitride region 12 further includes the ninth subregion 12i. The ninth subregion 12i is located between the seventh subregion 13g and the third electrode 53. The second nitride region 12 may further include the tenth subregion 12j. The eighth subregion 13h is located between the fifth subregion 11e and the tenth subregion 12j.

[0045] For example, the ninth subregion 12i is continuous with the sixth subregion 12f. For example, the tenth subregion 12j is continuous with the ninth subregion 12i. A homogeneous film is easily obtained in the continuous film-like second nitride region 12. More stable properties are easily obtained in the continuous film-like second nitride region 12.

[0046] Figure 3 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. As shown in Figure 3, the semiconductor device 112 according to this embodiment further includes a first insulating layer 45. The configuration of the semiconductor device 112, excluding the first insulating layer, may be the same as that of the semiconductor device 111.

[0047] The first insulating layer 45 is located between the eighth subregion 13h and the tenth subregion 12j. The first insulating layer 45 functions, for example, as a protective film. The first insulating layer 45 protects, for example, the third nitride region 13. The first insulating layer 45 may include at least one selected from the group consisting of, for example, SiN, SiON, SiO2, Al2O3, AlON, AlN, and AlSiON.

[0048] In the semiconductor device 112, the 10th subregion 12j may be amorphous. Alternatively, the crystallinity of the 6th subregion 12f is higher than that of the 10th subregion 12j. Lower crystallinity in the 10th subregion 12j suppresses leakage current, for example. High breakdown voltage is easier to obtain. More stable properties are easier to obtain. Lower crystallinity in the 10th subregion 12j makes it easier to suppress the entry of impurities (e.g., water or hydrogen) from the outside into the nitride semiconductor layer.

[0049] In the semiconductor device 112, the ninth subregion 12i may be amorphous. Alternatively, the crystallinity of the sixth subregion 12f may be higher than that of the ninth subregion 12i. Lower crystallinity in the ninth subregion 12i suppresses leakage current, for example. It is easier to obtain a high breakdown voltage. It is easier to obtain more stable characteristics.

[0050] Figure 4 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. As shown in Figure 4, in the semiconductor device 113 according to this embodiment, a step is provided between the fourth partial region 11d and the third partial region 11c. The configuration of the semiconductor device 113, excluding this step, may be the same as that of the semiconductor device 111.

[0051] In the semiconductor device 113, for example, the thickness of the fourth sub-region 11d is thinner than the thickness of the third sub-region 11c. These thicknesses are along the length in the second direction D2. For example, the direction from the sixth sub-region 12f to a part of the third sub-region 11c is along the first direction D1. The sixth sub-region 12f faces, for example, the side surface of the third sub-region 11c.

[0052] For example, in the manufacturing method described later, a portion of the film that will become the third nitride region 13 may be removed, and the second nitride region 12 may be formed in the removed region. When removing the portion of the film as described above, a portion of the first nitride region 11 may also be removed. This may create a step between the fourth partial region 11d and the third partial region 11c. For example, a wide range of manufacturing conditions can be used to stably obtain semiconductor devices with good characteristics.

[0053] Figure 5 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. As shown in Figure 5, in the semiconductor device 114 according to this embodiment, a portion of the third nitride region 13 is provided between the fourth partial region 11d and the sixth partial region 12f. The configuration of the semiconductor device 114, excluding this portion, may be the same as that of the semiconductor device 110.

[0054] In semiconductor device 114, the third nitride region 13 includes the eleventh subregion 13k. The eleventh subregion 13k is located between the fourth subregion 11d and the sixth subregion 12f. As described with respect to semiconductor device 113, a portion of the film that becomes the third nitride region 13 may be removed. During this removal, a portion of the film may remain. The remaining film corresponds to the eleventh subregion 13k. For example, semiconductor devices with good characteristics can be stably obtained by using a wide range of manufacturing conditions.

[0055] (Second Embodiment) In the second embodiment, the third electrode 53 is a p-type semiconductor. Figure 6 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. In the semiconductor device 120 according to the embodiment illustrated in Figure 6, the third electrode 53 includes a p-type nitride. The p-type nitride includes at least one selected from the group consisting of Al and Ga, and nitrogen. The third electrode 53 includes, for example, Mg. The third electrode 53 is in contact with the seventh partial region 13g. The configuration of the semiconductor device 120, apart from the above, may be the same as that of, for example, the semiconductor device 110.

[0056] In the semiconductor device 120, the third electrode 53 includes, for example, p-type AlGaN or p-type GaN. For example, the desired operation can be obtained with a simple configuration. Normally-off operation can be obtained.

[0057] Figure 7 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. As shown in Figure 7, in the semiconductor device 121 according to this embodiment, the second nitride region 12 further includes a tenth subregion 12j. The configuration of the semiconductor device 121, excluding this region, may be the same as that of, for example, the semiconductor device 120.

[0058] In the semiconductor device 121, the third nitride region 13 includes the eighth subregion 13h. The direction from the fifth subregion 11e to the eighth subregion 13h is along the second direction D2. The eighth subregion 13h is located between the fifth subregion 11e and the tenth subregion 12j. The provision of the tenth subregion 12j protects the eighth subregion 13h.

[0059] Figure 8 is a schematic cross-sectional view illustrating a semiconductor device according to the second embodiment. As shown in Figure 8, in the semiconductor device 122 according to this embodiment, the third nitride region 13 includes the eleventh subregion 13k. The configuration of the semiconductor device 122, excluding this region, may be the same as that of the semiconductor device 121, for example.

[0060] In the semiconductor device 122, the 11th subregion 13k is located between the 4th subregion 11d and the 6th subregion 12f. For example, a portion of the film that becomes the 3rd nitride region 13 may be removed. During this removal, a portion of the film may remain. The remaining film corresponds to the 11th subregion 13k. For example, a semiconductor device with good characteristics can be stably obtained by using a wide range of manufacturing conditions.

[0061] The following describes an example of a method for manufacturing a semiconductor device according to the embodiment. The following describes an example of a method for manufacturing the semiconductor device 113.

[0062] Figures 9(a) to 9(d) and 10(a) to 10(c) are schematic cross-sectional views illustrating a method for manufacturing a semiconductor device according to an embodiment. As shown in Figure 9(a), a third nitride film 13F, which becomes a third nitride region 13, is formed on the first nitride region 11.

[0063] As shown in Figure 9(b), a portion of the third nitride film 13F is removed. This removal may be carried out, for example, by dry etching using a chlorine-based gas. In this etching process, a portion of the first nitride region 11 may also be removed.

[0064] As shown in Figure 9(c), a second nitride film 12F, which becomes the second nitride region 12, is formed. The second nitride film 12F may be formed, for example, by epitaxial growth.

[0065] As shown in Figure 9(d), a first insulating film 41F, which will become the first insulating member 41, is formed. As shown in Figure 10(a), a third electrode 53 is formed.

[0066] As shown in Figure 10(b), the second nitride film 12F and the first insulating film 41F are removed from the region where the first electrode 51 and the second electrode 52 are formed. This results in the second nitride region 12 and the first insulating member 41.

[0067] As shown in Figure 10(c), the first electrode 51 and the second electrode 52 are formed. This results in the semiconductor device 113.

[0068] In the embodiment, at least one of the first electrode 51 and the second electrode 52 includes, for example, at least one selected from the group consisting of aluminum, titanium, nickel, and gold. The third electrode 53 includes, for example, at least one selected from the group consisting of TiN, WN, Ni, Au, Pt, and Ti. The third electrode 53 may include, for example, conductive silicon or polysilicon. The third electrode 53 may include, for example, conductive GaN. The third electrode 53 may include, for example, polyGaN or polyAlGaN.

[0069] Information regarding length and thickness can be obtained through electron microscopy observations, etc. Information regarding the material composition can be obtained through SIMS (Secondary Ion Mass Spectrometry) or EDX (Energy dispersive X-ray spectroscopy), etc.

[0070] The embodiment may include the following configuration (e.g., proposed technical details).

[0071] (Composition 1) First electrode and, A second electrode, wherein a direction from the first electrode to the second electrode follows a first direction, the second electrode, A third electrode, wherein a position of the third electrode in the first direction is between a position of the first electrode in the first direction and a position of the second electrode in the first direction, the third electrode, Al x1 Ga 1-x1 A first nitride region containing Alx1Ga1 - x1N (0 ≦ x1 < 1), wherein the first nitride region includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, a direction from the first partial region to the first electrode follows a second direction intersecting with the first direction, a direction from the second partial region to the second electrode follows the second direction, a direction from the third partial region to the third electrode follows 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 a position of the third partial region in the first direction and a position of the second partial region in the first direction, the first nitride region, Al x2 Ga 1-x2 A second nitride region containing Alx2Ga1 - x2N (x1 < x2 ≦ 1) or In, wherein the second nitride region includes a sixth partial region, and a direction from the fourth partial region to the sixth partial region follows the second direction, the second nitride region, y Al z Ga (1-y-z) A third nitride region containing AlyGa1 - yNzIn1 - y - z (0 < y ≦ 1, 0 ≦ z < 1, y + z ≦ 1), wherein the third nitride region includes a seventh partial region, and the seventh partial region is the third nitride region between the third partial region and the third electrode, Al x3 Ga 1-x3 A third nitride region containing Alx3Ga1 - x3N (x1 < x3 < x2), wherein the third nitride region includes a seventh partial region, and the seventh partial region is the third nitride region between the third partial region and the third electrode, A semiconductor device comprising the above.

[0072] (Configuration 2) The sixth partial region has a first thickness along the second direction. The seventh portion region has a second thickness along the second direction, The semiconductor device according to configuration 1, wherein the first thickness is thinner than the second thickness.

[0073] (Composition 3) The third nitride region further includes an eighth subregion, The semiconductor device according to configuration 2, wherein the direction from the fifth subregion to the eighth subregion is along the second direction.

[0074] (Composition 4) The sixth partial region has a first thickness along the second direction, The seventh portion region has a second thickness along the second direction, The eighth portion region has a third thickness along the second direction, The first thickness is thinner than the second thickness. The semiconductor device according to configuration 3, wherein the first thickness is thinner than the third thickness.

[0075] (Composition 5) The second nitride region further includes a ninth subregion, The semiconductor device according to configuration 3 or 4, wherein the ninth subregion is located between the seventh subregion and the third electrode.

[0076] (Composition 6) The second nitride region further includes a tenth subregion, The eighth subregion is located between the fifth subregion and the tenth subregion, and is the semiconductor device according to configuration 5.

[0077] (Composition 7) The aforementioned tenth subregion is amorphous, or The semiconductor device according to configuration 6, wherein the crystallinity in the sixth subregion is higher than the crystallinity in the tenth subregion.

[0078] (Composition 8) Further comprising a first insulating layer, The semiconductor device according to configuration 7, wherein the first insulating layer is located between the eighth subregion and the tenth subregion.

[0079] (Composition 9) The semiconductor device according to any one of configurations 1 to 8, wherein the direction from the sixth subregion to a part of the third subregion is along the first direction.

[0080] (Composition 10) The third nitride region includes an eleventh subregion, The 11th subregion is located between the 4th subregion and the 6th subregion, and is a semiconductor device according to any one of configurations 1 to 8.

[0081] (Composition 11) The first insulating member further comprises a first insulating region, The semiconductor device according to any one of configurations 1 to 10, wherein the first insulating region is located between the third partial region and the third electrode.

[0082] (Composition 12) The semiconductor device according to configuration 11, wherein the sixth sub-region is located between the fourth sub-region and a part of the first insulating member.

[0083] (Composition 13) The third electrode contains a p-type nitride, The semiconductor device according to configuration 1 or 2, wherein the p-type nitride comprises at least one selected from the group consisting of Al and Ga, and nitrogen.

[0084] (Composition 14) The semiconductor device according to configuration 13, wherein the third electrode is in contact with the seventh subregion.

[0085] (Composition 15) The third nitride region further includes an eighth subregion, The direction from the fifth subregion to the eighth subregion is along the second direction, The second nitride region further includes a tenth subregion, The eighth partial region is the semiconductor device according to Configuration 13 or 14, which is between the fifth partial region and the tenth partial region.

[0086] (Configuration 16) The third nitride region includes an eleventh partial region, The eleventh partial region is the semiconductor device according to Configuration 13 or 14, which is between the fourth partial region and the sixth partial region.

[0087] (Configuration 17) The second nitride region contains Al x2 Ga 1-x2 N (where x1 < x2 ≤ 1), where x2 is 0.8 or more and 1 or less, where x3 is 0.1 or more and 0.35 or less, the semiconductor device according to any one of Configurations 1 to 16.

[0088] (Configuration 18) The first thickness is ½ or less of the second thickness, the semiconductor device according to Configuration 2.

[0089] (Configuration 19) The first thickness is 1 nm or more and 10 nm or less, The second thickness is 20 nm or more and 40 nm or less, the semiconductor device according to Configuration 2.

[0090] (Configuration 20) The first electrode includes a first electrode surface, <s The direction from the first partial region to the first electrode surface is along the second direction, The second electrode includes a second electrode surface, The direction from the second partial region to the second electrode surface is along the second direction, The distance in the second direction between the position of the first electrode surface in the second direction and the position of the second electrode surface in the second direction is 50 nm or less, the semiconductor device according to any one of Configurations 1 to 19.

[0091] According to the embodiment, a semiconductor device with improved characteristics can be provided.

[0092] 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, the specific configuration of each element included in a semiconductor device, such as semiconductor material, nitride region, electrode, and insulating material, is included within the scope of the present invention as long as it can be implemented in the same manner and similar effects can be obtained by appropriately selecting from the range known to those skilled in the art.

[0093] Furthermore, combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.

[0094] Furthermore, all semiconductor devices that a person skilled in the art can implement by appropriately modifying the design based on the semiconductor device described above as an embodiment of the present invention also fall within the scope of the present invention, insofar as they encompass the gist of the present invention.

[0095] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention.

[0096] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0097] 10M…Semiconductor material, 10c…Carrier region, 11~13…1st to 3rd nitride regions, 11a~11e…1st to 5th subregions, 12F…2nd nitride film, 12f…6th subregion, 12i…9th subregion, 12j…10th subregion, 13F…3rd nitride film, 13g…7th subregion, 13h…8th subregion, 13k…11th subregion, 18b…Nitride layer, 18s…Substrate, 41…1st insulating material, 41F…1st insulating film, 41a…1st insulating region, 45…1st insulating layer, 51~53…1st to 3rd electrodes, 51f, 52f…1st and 2nd electrode surfaces, 110~114, 120~122…Semiconductor device, D1, D2…1st and 2nd directions, t1~t3…1st to 3rd thicknesses

Claims

1. First electrode and, The second electrode is such that the direction from the first electrode to the second electrode is along the first direction, A third electrode, wherein the position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. Al ｘ１ Ga １－ｘ１ A first nitride region comprising N (0 ≤ x1 < 1), wherein the first nitride region includes a first subregion, a second subregion, a third subregion, a fourth subregion and a fifth subregion, the direction from the first subregion to the first electrode is along a second direction intersecting the first direction, the direction from the second subregion to the second electrode is along the second direction, the direction from the third subregion to the third electrode is along the second direction, the position of the fourth subregion in the first direction is between the position of the first subregion in the first direction and the position of the third subregion in the first direction, and the position of the fifth subregion in the first direction is between the position of the third subregion in the first direction and the position of the second subregion in the first direction, Al ｘ２ Ga １－ｘ２ N (x1 < x2 ≤ 1) or In ｙ Al ｚ Ga （１－ｙ－ｚ） A second nitride region containing N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1), wherein the second nitride region includes a sixth subregion, and the direction from the fourth subregion to the sixth subregion is along the second direction, Al ｘ３ Ga １－ｘ３ A third nitride region containing N (x1 < x3 < x2), wherein the third nitride region includes a seventh sub-region, and the seventh sub-region is the third nitride region between the third sub-region and the third electrode, and Equipped with, The sixth partial region has a first thickness along the second direction, The seventh portion region has a second thickness along the second direction, The first thickness is thinner than the second thickness. The third nitride region further includes an eighth subregion, The direction from the fifth subregion to the eighth subregion is along the second direction, The second nitride region further includes a ninth subregion, The ninth subregion is located between the seventh subregion and the third electrode. The second nitride region further includes a tenth subregion, The eighth subregion is located between the fifth subregion and the tenth subregion. The aforementioned tenth subregion is amorphous, or A semiconductor device wherein the crystallinity in the sixth subregion is higher than that in the tenth subregion.

2. Further comprising a first insulating layer, The semiconductor device according to claim 1, wherein the first insulating layer is located between the eighth partial region and the tenth partial region.

3. The eighth portion region has a third thickness along the second direction, The semiconductor device according to claim 1, wherein the first thickness is thinner than the third thickness.

4. The semiconductor device according to claim 1, wherein the direction from the sixth subregion to a part of the third subregion is along the first direction.

5. First electrode and, The second electrode is such that the direction from the first electrode to the second electrode is along the first direction, A third electrode, wherein the position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. Al ｘ１ Ga １－ｘ１ A first nitride region comprising N (0 ≤ x1 < 1), wherein the first nitride region includes a first subregion, a second subregion, a third subregion, a fourth subregion and a fifth subregion, the direction from the first subregion to the first electrode is along a second direction intersecting the first direction, the direction from the second subregion to the second electrode is along the second direction, the direction from the third subregion to the third electrode is along the second direction, the position of the fourth subregion in the first direction is between the position of the first subregion in the first direction and the position of the third subregion in the first direction, and the position of the fifth subregion in the first direction is between the position of the third subregion in the first direction and the position of the second subregion in the first direction, Al ｘ２ Ga １－ｘ２ N (x1 < x2 ≤ 1) or In ｙ Al ｚ Ga （１－ｙ－ｚ） A second nitride region containing N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1), wherein the second nitride region includes a sixth subregion, and the direction from the fourth subregion to the sixth subregion is along the second direction, Al ｘ３ Ga １－ｘ３ A third nitride region including N (x1 < x3 < x2), wherein the third nitride region includes a seventh subregion, and the seventh subregion is located between the third subregion and the third electrode, Equipped with, A semiconductor device in which the direction from the sixth sub-region to a part of the third sub-region is along the first direction.

6. The third nitride region includes an eleventh subregion, The semiconductor device according to claim 1, wherein the eleventh subregion is located between the fourth subregion and the sixth subregion.

7. The first insulating member further includes a first insulating region, The semiconductor device according to claim 1, wherein the first insulating region is located between the third partial region and the third electrode.

8. The semiconductor device according to claim 7, wherein the sixth sub-region is located between the fourth sub-region and a part of the first insulating member.

9. First electrode and, The second electrode is such that the direction from the first electrode to the second electrode is along the first direction, A third electrode, wherein the position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. Al ｘ１ Ga １－ｘ１ A first nitride region comprising N (0 ≤ x1 < 1), wherein the first nitride region includes a first subregion, a second subregion, a third subregion, a fourth subregion and a fifth subregion, the direction from the first subregion to the first electrode is along a second direction intersecting the first direction, the direction from the second subregion to the second electrode is along the second direction, the direction from the third subregion to the third electrode is along the second direction, the position of the fourth subregion in the first direction is between the position of the first subregion in the first direction and the position of the third subregion in the first direction, and the position of the fifth subregion in the first direction is between the position of the third subregion in the first direction and the position of the second subregion in the first direction, Al ｘ２ Ga １－ｘ２ N (x1 < x2 ≤ 1) or In ｙ Al ｚ Ga （１－ｙ－ｚ） A second nitride region containing N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1), wherein the second nitride region includes a sixth subregion, and the direction from the fourth subregion to the sixth subregion is along the second direction, Al ｘ３ Ga １－ｘ３ A third nitride region including N (x1 < x3 < x2), wherein the third nitride region includes a seventh subregion, and the seventh subregion is located between the third subregion and the third electrode, Equipped with, The first insulating member further includes a first insulating region, The first insulating region is located between the third partial region and the third electrode. The sixth sub-region is a semiconductor device located between the fourth sub-region and a part of the first insulating member.

10. First electrode and, The second electrode is such that the direction from the first electrode to the second electrode is along the first direction, A third electrode, wherein the position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. Al ｘ１ Ga １－ｘ１ A first nitride region comprising N (0 ≤ x1 < 1), wherein the first nitride region includes a first subregion, a second subregion, a third subregion, a fourth subregion and a fifth subregion, the direction from the first subregion to the first electrode is along a second direction intersecting the first direction, the direction from the second subregion to the second electrode is along the second direction, the direction from the third subregion to the third electrode is along the second direction, the position of the fourth subregion in the first direction is between the position of the first subregion in the first direction and the position of the third subregion in the first direction, and the position of the fifth subregion in the first direction is between the position of the third subregion in the first direction and the position of the second subregion in the first direction, Al ｘ２ Ga １－ｘ２ N (x1 < x2 ≤ 1) or In ｙ Al ｚ Ga （１－ｙ－ｚ） A second nitride region containing N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1), wherein the second nitride region includes a sixth subregion, and the direction from the fourth subregion to the sixth subregion is along the second direction, Al ｘ３ Ga １－ｘ３ A third nitride region including N (x1 < x3 < x2), wherein the third nitride region includes a seventh subregion, and the seventh subregion is located between the third subregion and the third electrode, Equipped with, The third electrode contains a p-type nitride, The p-type nitride comprises at least one selected from the group consisting of Al and Ga, and nitrogen. The third electrode is a semiconductor device in contact with the seventh subregion.

11. The third nitride region further includes an eighth subregion, The direction from the fifth subregion to the eighth subregion is along the second direction, The second nitride region further includes a tenth subregion, The semiconductor device according to claim 10, wherein the eighth subregion is located between the fifth subregion and the tenth subregion.

12. The third nitride region includes an eleventh subregion, The semiconductor device according to claim 10, wherein the eleventh subregion is located between the fourth subregion and the sixth subregion.

13. The second nitride region is the Al ｘ２ Ga １－ｘ２ N (including x1 < x2 ≤ 1), The aforementioned x2 is between 0.8 and 1, The semiconductor device according to any one of claims 1 to 12, wherein x3 is 0.1 or more and 0.35 or less.

14. The semiconductor device according to claim 1, wherein the first thickness is 0.5 times or less the second thickness.

15. The first thickness is 1 nm or more and 10 nm or less. The semiconductor device according to claim 1, wherein the second thickness is 20 nm or more and 40 nm or less.

16. The first electrode includes the first electrode surface, The direction from the first partial region to the first electrode surface is along the second direction, The second electrode includes the second electrode surface, The direction from the second partial region to the second electrode surface is along the second direction, The semiconductor device according to claim 1, wherein the distance in the second direction between the position of the first electrode surface in the second direction and the position of the second electrode surface in the second direction is 50 nm or less.

17. First electrode and, The second electrode is such that the direction from the first electrode to the second electrode is along the first direction, A third electrode, wherein the position of the third electrode in the first direction is between the position of the first electrode in the first direction and the position of the second electrode in the first direction. Al ｘ１ Ga １－ｘ１ A first nitride region comprising N (0 ≤ x1 < 1), wherein the first nitride region includes a first subregion, a second subregion, a third subregion, a fourth subregion and a fifth subregion, the direction from the first subregion to the first electrode is along a second direction intersecting the first direction, the direction from the second subregion to the second electrode is along the second direction, the direction from the third subregion to the third electrode is along the second direction, the position of the fourth subregion in the first direction is between the position of the first subregion in the first direction and the position of the third subregion in the first direction, and the position of the fifth subregion in the first direction is between the position of the third subregion in the first direction and the position of the second subregion in the first direction, Al ｘ２ Ga １－ｘ２ N (x1 < x2 ≤ 1) or In ｙ Al ｚ Ga （１－ｙ－ｚ） A second nitride region containing N (0 < y ≤ 1, 0 ≤ z < 1, y + z ≤ 1), wherein the second nitride region includes a sixth subregion, and the direction from the fourth subregion to the sixth subregion is along the second direction, Al ｘ３ Ga １－ｘ３ A third nitride region including N (x1 < x3 < x2), wherein the third nitride region includes a seventh subregion, and the seventh subregion is located between the third subregion and the third electrode, Equipped with, The first nitride region is in contact with the second nitride region and the third nitride region, and is a semiconductor device.

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