Semiconductor device

Abstract

The present invention provides a semiconductor device capable of improving characteristics. According to an embodiment, this semiconductor device includes first to third electrodes, and first to fourth semiconductor members. The third electrode extends along a second direction intersecting a first direction heading from the first electrode toward the second electrode. The first semiconductor member is a first conductivity type. A fifth partial region of the first semiconductor member is in Schottky contact with the second electrode. The second semiconductor member is a second conductivity type. The third semiconductor member is the second conductivity type. A third semiconductor section of the third semiconductor member is electrically connected to the second electrode. The impurity concentration of the third semiconductor member is higher than the impurity concentration of the second semiconductor member. The fourth semiconductor member is the first conductivity type. A second semiconductor region of the fourth semiconductor member is electrically connected to the second electrode. The impurity concentration of the fourth semiconductor member is higher than the impurity concentration of the first semiconductor member.

Description

Semiconductor Devices

[0001] FIELD An embodiment of the present invention relates to a semiconductor device.

[0002] For example, in semiconductor devices including Schottky barrier diodes, improvements in characteristics are desired.

[0003] JP 2023-45865 A

[0004] The embodiments provide a semiconductor device capable of improving characteristics.

[0005] According to an embodiment, a semiconductor device includes a first electrode, a second electrode, a third electrode, a first semiconductor member, a second semiconductor member, a third semiconductor member, and a fourth semiconductor member. The third electrode extends along a second direction intersecting a first direction from the first electrode to the second electrode. The first semiconductor member is of a first conductivity type. The first semiconductor member includes a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region. The first partial region is provided between the first electrode and the third electrode in the first direction. A third direction from the first partial region to the second partial region intersects a plane including the first direction and the second direction. The third partial region is provided between the first partial region and the third electrode in the first direction. The direction from the second partial region to the fourth partial region is along the second direction. The direction from the fourth partial region to the fifth partial region is along the first direction. The fifth partial region is in Schottky contact with the second electrode. The second semiconductor member is of the second conductivity type. The second semiconductor member includes a first portion and a second portion. The third semiconductor member is of the second conductivity type. The first portion is provided between the second partial region and the third semiconductor member in the first direction. A direction from at least a portion of the third semiconductor member to the fifth partial region is along the second direction. The third semiconductor member includes a first semiconductor portion, a second semiconductor portion, and a third semiconductor portion. A direction from the first semiconductor portion to the third semiconductor portion is along the third direction. A direction from the third semiconductor portion to the second semiconductor portion is along the second direction. The third semiconductor portion is electrically connected to the second electrode. A third impurity concentration of the second conductivity type of the third semiconductor member is higher than a second impurity concentration of the second conductivity type of the second semiconductor member. The fourth semiconductor member is of the first conductivity type. The fourth semiconductor member includes a first semiconductor region and a second semiconductor region. The first semiconductor portion is provided between the first portion and the first semiconductor region in the first direction. The second semiconductor portion is provided between the first portion and the second semiconductor region in the first direction, and the second semiconductor region is electrically connected to the second electrode.The second portion is provided in the third direction between the third portion region and the first semiconductor portion, between the third portion region and the first semiconductor region, between the third portion region and the second semiconductor portion, and between the third portion region and the second semiconductor region. A second semiconductor region length in the third direction of the second semiconductor region is longer than a first semiconductor region length in the third direction of the first semiconductor region. A fourth impurity concentration of the first conductivity type in the fourth semiconductor member is higher than a first impurity concentration of the first conductivity type in the first semiconductor member.

[0006] FIG. 1 is a schematic perspective view illustrating a semiconductor device according to a first embodiment. FIG. 2 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. FIG. 3 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. FIG. 4 is a schematic cross-sectional view illustrating a semiconductor device according to the first embodiment. FIG. 5 is a schematic plan view illustrating a semiconductor device according to the first embodiment. FIG. 6 is a schematic plan view illustrating a semiconductor device according to a second embodiment. FIG. 7 is a schematic plan view illustrating a semiconductor device according to the second embodiment.

[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 size ratio between parts, etc., are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions will be omitted as appropriate.

[0008] First Embodiment FIG. 1 is a schematic perspective view illustrating a semiconductor device according to a first embodiment. FIGS. 2 to 4 are schematic cross-sectional views illustrating the semiconductor device according to the first embodiment. FIG. 5 is a schematic plan view illustrating the semiconductor device according to the first embodiment. FIG. 2 is a cross-sectional view taken along line A1-A2 in FIG. 5. FIG. 3 is a cross-sectional view taken along line A3-A4 in FIG. 5. FIG. 4 is a cross-sectional view taken along line A5-A6 in FIG. 5.

[0009] 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 semiconductor member 11, a second semiconductor member 12, a third semiconductor member 13, and a fourth semiconductor member 14.

[0010] A first direction D1 from the first electrode 51 to the second electrode 52 is defined as the Z-axis direction. A direction perpendicular to the Z-axis direction is defined as the X-axis direction. A direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction.

[0011] The third electrode 53 extends along a second direction D2. The second direction D2 intersects with the first direction D1 from the first electrode 51 to the second electrode 52. The second direction D2 may be, for example, the Y-axis direction.

[0012] The first semiconductor member 11 is of a first conductivity type. The first semiconductor member 11 includes a first partial region 11a, a second partial region 11b, a third partial region 11c, a fourth partial region 11d, and a fifth partial region 11e. The first partial region 11a is provided between the first electrode 51 and the third electrode 53 in the first direction D1. A third direction D3 extending from the first partial region 11a to the second partial region 11b intersects with a plane including the first direction D1 and the second direction D2. The third direction D3 is, for example, the X-axis direction.

[0013] The third partial region 11c is provided between the first partial region 11a and the third electrode 53 in the first direction D1. The direction from the second partial region 11b to the fourth partial region 11d is along the second direction D2. The direction from the fourth partial region 11d to the fifth partial region 11e is along the first direction D1. The fifth partial region 11e is in Schottky contact with the second electrode 52. The boundaries between the first partial region 11a, the second partial region 11b, the third partial region 11c, the fourth partial region 11d, and the fifth partial region 11e may be clear or unclear.

[0014] The second semiconductor member 12 has a second conductivity type. The first conductivity type is one of n-type and p-type. The second conductivity type is the other of n-type and p-type. In the following, the first conductivity type is n-type and the second conductivity type is p-type.

[0015] The second semiconductor member 12 includes a first portion 12 a and a second portion 12 b. As described below, the second semiconductor member 12 may include a third portion 12 c. The boundaries between the first portion 12 a, the second portion 12 b, and the third portion 12 c may be clear or unclear.

[0016] The third semiconductor member 13 has the second conductivity type. The first portion 12a is provided in the first direction D1 between the second partial region 11b and the third semiconductor member 13. The direction from at least a part of the third semiconductor member 13 to the fifth partial region 11e is along the second direction D2.

[0017] The third semiconductor member 13 includes a first semiconductor portion 13a, a second semiconductor portion 13b, and a third semiconductor portion 13c. The direction from the first semiconductor portion 13a to the third semiconductor portion 13c is along the third direction D3. The direction from the third semiconductor portion 13c to the second semiconductor portion 13b is along the second direction D2. The third semiconductor portion 13c is electrically connected to the second electrode 52. For example, the third semiconductor portion 13c is in ohmic contact with the second electrode 52. The boundaries between the first semiconductor portion 13a, the second semiconductor portion 13b, and the third semiconductor portion 13c may be clear or unclear.

[0018] The third semiconductor member 13 has a third impurity concentration of the second conductivity type higher than the second impurity concentration of the second conductivity type in the second semiconductor member 12. The second semiconductor member 12 is, for example, a p-type region. The third semiconductor member 13 is, for example, a p ＋ It is an area.

[0019] The fourth semiconductor member 14 is of the first conductivity type. The fourth semiconductor member 14 includes a first semiconductor region 14a and a second semiconductor region 14b. The first semiconductor portion 13a is provided between the first portion 12a and the first semiconductor region 14a in the first direction D1. The second semiconductor portion 13b is provided between the first portion 12a and the second semiconductor region 14b in the first direction D1. The second semiconductor region 14b is electrically connected to the second electrode 52. For example, the second semiconductor region 14b is in ohmic contact with the second electrode 52. The boundary between the first semiconductor region 14a and the second semiconductor region 14b may be clear or unclear.

[0020] The second portion 12b is provided in the third direction D3 between the third partial region 11c and the first semiconductor portion 13a, between the third partial region 11c and the first semiconductor region 14a, between the third partial region 11c and the second semiconductor portion 13b, and between the third partial region 11c and the second semiconductor region 14b (see Figures 2 and 3).

[0021] The fourth impurity concentration of the first conductivity type in the fourth semiconductor member 14 is higher than the first impurity concentration of the first conductivity type in the first semiconductor member 11. The first semiconductor member 11 includes, for example, an n-type region. － The fourth semiconductor member 14 may further include a region. ＋ The fourth semiconductor member 14 includes an n ＋＋ It may further include regions.

[0022] 2, the length of the second semiconductor region 14b in the third direction D3 is defined as a second semiconductor region length 14bx. As shown in Fig. 3, the length of the first semiconductor region 14a in the third direction D3 is defined as a first semiconductor region length 14ax. The second semiconductor region length 14bx is longer than the first semiconductor region length 14ax.

[0023] 1, in this example, at least a portion of the second semiconductor portion 13b is provided between the third semiconductor portion 13c and the fifth partial region 11e in the third direction D3. For example, the position of the second semiconductor region 14b in the second direction D2 is between the position of the third semiconductor portion 13c in the second direction D2 and the position of the fifth partial region 11e in the second direction D2.

[0024] In the semiconductor device 110, 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 second electrode 52. The first electrode 51 functions as, for example, a drain electrode. The second electrode 52 functions as, for example, a source electrode. The third electrode 53 functions as, for example, a gate electrode. The semiconductor device 110 is, for example, a transistor.

[0025] 1 , the semiconductor device 110 may further include a first insulating member 41. The first insulating member 41 includes a first insulating region 41a. At least a portion of the first insulating region 41a is provided between the third partial region 11c and the third electrode 53. A portion of the first insulating member 41 may be provided between the fourth semiconductor member 14 and the third electrode 53. The semiconductor device 110 is a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor).

[0026] As already explained, the semiconductor device 110 is provided with a fifth partial region 11e that forms a Schottky junction with the second electrode 52. The region including the fifth partial region 11e functions, for example, as an SBD (Schottky Barrier Diode). The third partial region 11c corresponds, for example, to a JFET (Junction Field Effect Transistor) region. The region including the fourth semiconductor member 14 functions as a p-n body diode. By providing the SBD in the semiconductor device 110, a current flows through the SBD when, for example, a reverse voltage is applied. This makes it difficult for the p-n body diode to be turned on.

[0027] 2 (a cross section including the second semiconductor region 14b), the length of the boundary of the second semiconductor region 14b in contact with the second electrode 52 is longer than the length of the boundary of the second semiconductor portion 13b in contact with the second electrode 52. In the region shown in FIG. 2, the area of ​​the n-type contact region is larger than the area of ​​the p-type contact region.

[0028] 3 (a cross section including the third semiconductor portion 13c), the length of the boundary of the third semiconductor portion 13c in contact with the second electrode 52 is longer than the length of the boundary of the first semiconductor region 14a in contact with the second electrode 52. In the region shown in FIG. 3, the area of ​​the p-type contact region is larger than the area of ​​the n-type contact region.

[0029] In the semiconductor device 110, two types of regions are provided, with different relative areas between the n-type contact region and the p-type contact region. This makes it easier to achieve the desired characteristics of the semiconductor device 110. When the area of ​​the n-type contact region is large, for example, the contact resistance can be reduced, resulting in low on-resistance. When the area of ​​the p-type contact region is large, for example, high-speed switching can be achieved. According to the embodiment, a semiconductor device with improved characteristics can be provided.

[0030] 5, the semiconductor device 110 includes a first region r1, a second region r2, and a third region r3. The first region r1 corresponds to a region where the fifth partial region 11e is provided. The second region r2 corresponds to a region where the third semiconductor portion 13c is provided. The third region r3 corresponds to a region where the second semiconductor region 14b is provided. The first region r1 corresponds to an SBD region. The second region r2 corresponds to a region where the p-type contact region has a large area (p-contact region). The third region r3 corresponds to a region where the n-type contact region has a large area (n-contact region).

[0031] In the semiconductor device 110, the SBD region, the p-contact region, and the n-contact region are compactly arranged along the second direction D2. A small-sized semiconductor device with good characteristics can be provided. According to the embodiment, a semiconductor device with improved characteristics can be provided.

[0032] 5, the length of the third semiconductor portion 13c along the second direction D2 is defined as a third width 13cy. The length of the second semiconductor region 14b along the second direction D2 is defined as a second width 14by. In one example, the ratio of the third width 13cy to the second width 14by is, for example, not less than 0.1 and not more than 10. For example, well-balanced characteristics can be easily obtained.

[0033] In the embodiment, the second semiconductor region length 14bx may be, for example, 1.1 times or more the first semiconductor region length 14ax. The second semiconductor region length 14bx may be, for example, 1.3 times or more the first semiconductor region length 14ax. The second semiconductor region length 14bx may be, for example, 10 times or less the first semiconductor region length 14ax. The second semiconductor region length 14bx may be, for example, 5 times or less the first semiconductor region length 14ax. In the semiconductor device 110, the second semiconductor region length 14bx (see FIG. 2) may be, for example, 0.1 μm or more and 3 μm or less. The first semiconductor region length 14ax (see FIG. 3) may be, for example, 0.2 μm or more and 5 μm or less.

[0034] 2, the length of the second semiconductor portion 13b in the third direction D3 is defined as a second semiconductor portion length 13bx. As shown in Fig. 3, the length of the first semiconductor portion 13a in the third direction D3 is defined as a first semiconductor portion length 13ax. The second semiconductor portion length 13bx is longer than the first semiconductor portion length 13ax.

[0035] As shown in FIG. 3 , in the third semiconductor member 13, the thick region corresponds to the first semiconductor portion 13a. The thin region corresponds to the third semiconductor portion 13c. The length of the first semiconductor portion 13a in the first direction D1 is defined as the first thickness 13az. The length of the third semiconductor portion 13c in the first direction D1 is defined as the third thickness 13cz. The third thickness 13cz is thinner than the first thickness 13az. For example, the first thickness 13az may be 1.1 times or more and 5 times or less the third thickness 13cz. For example, the first thickness 13az may be 0.1 μm or more and 0.5 μm or less. The third thickness 13cz may be 20 nm or more and 300 nm or less.

[0036] 2, the length of the second semiconductor portion 13b in the first direction D1 is defined as the second thickness 13bz. The third thickness 13cz is thinner than the second thickness 13bz. For example, the second thickness 13bz may be 1.1 to 5 times the third thickness 13cz. For example, the second thickness 13bz may be 0.1 μm to 0.5 μm.

[0037] In one example, the thickness (length in the Z-axis direction) of the first semiconductor region 14a is, for example, 20 nm to 300 nm, the thickness (length in the Z-axis direction) of the first portion 12a may be, for example, 50 nm to 500 nm, and the thickness (length in the Z-axis direction) of the second portion 12b may be, for example, 200 nm to 800 nm.

[0038] 2, 3, and 5, the fourth semiconductor member 14 may include a high-concentration region 14p and a low-concentration region 14q. The high-concentration region 14p is provided between the low-concentration region 14q and the second electrode 52. The impurity concentration of the first conductivity type in the high-concentration region 14p is higher than the impurity concentration of the first conductivity type in the low-concentration region 14q. The high-concentration region 14p may be, for example, n ＋＋ The low concentration region 14q is, for example, ＋ It is an area.

[0039] When the fourth semiconductor member 14 includes a high concentration region 14p and a low concentration region 14q, the impurity concentration of the second conductivity type (fourth impurity concentration) in the fourth semiconductor member 14 may be the average of the impurity concentrations of the second conductivity type in the high concentration region 14p and the low concentration region 14q.

[0040] 2 and 3, the second electrode 52 may include a first electrode portion 52a and a second electrode portion 52b. The first electrode portion 52a is provided between the third semiconductor member 13 and the second electrode portion 52b, and between the fourth semiconductor member 14 and the second electrode portion 52b. For example, at least a portion of the first electrode portion 52a is provided in the first direction D1 between the third semiconductor portion 13c and the second electrode portion 52b, and between the second semiconductor region 14b and the second electrode portion 52b. The first electrode portion 52a includes, for example, a silicide. For example, the first electrode portion 52a may include, for example, NiSi. The second electrode portion 52b may include, for example, a metal such as aluminum.

[0041] 4, the second electrode 52 may include a third electrode portion 52c. The third electrode portion 52c faces the fifth sub-region 11e. For example, the third electrode portion 52c may be provided between the fifth sub-region 11e and the second electrode portion 52b. The third electrode portion 52c may include, for example, at least one selected from the group consisting of Ni, Ti, V, and Mo. A Schottky junction is obtained in the region including the third electrode portion 52c.

[0042] 1 and 4, the second semiconductor member 12 may include a third portion 12c. At least a portion of the third portion 12c is provided between the third semiconductor member 13 and the fifth partial region 11e and between the fourth semiconductor member 14 and the fifth partial region 11e in the second direction D2. As shown in Fig. 4, a portion of the third portion 12c is provided between the second portion 12b and the fifth partial region 11e in the third direction D3. A portion of the third portion 12c is provided between the fourth semiconductor member 14 and the fifth partial region 11e in the third direction D3.

[0043] 1 , the semiconductor device 110 may further include a fifth semiconductor member 15 of the first conductivity type. The fifth semiconductor member 15 is provided between the first electrode 51 and the first semiconductor member 11 in the first direction D1. A fifth impurity concentration of the first conductivity type in the fifth semiconductor member 15 is higher than the first impurity concentration in the first semiconductor member 11. The fifth semiconductor member 15 may correspond to, for example, at least one of a buffer layer and a substrate. A low-resistance electrical connection is obtained.

[0044] 6 is a schematic plan view illustrating a semiconductor device according to a second embodiment. As shown in FIG. 6, in a semiconductor device 111 according to the embodiment, the positional relationship between the third semiconductor portion 13c of the third semiconductor member 13 and the second semiconductor region 14b of the fourth semiconductor member 14 is different from the positional relationship in the semiconductor device 110. Except for this, the configuration of the semiconductor device 111 may be the same as the configuration of the semiconductor device 110.

[0045] 6, in the semiconductor device 111, at least a portion of the third semiconductor portion 13c is provided between the second semiconductor portion 13b and the fifth partial region 11e in the second direction D2. For example, the position of the third semiconductor portion 13c in the second direction D2 is between the position of the second semiconductor region 14b in the second direction D2 and the position of the fifth partial region 11e in the second direction D2.

[0046] In the semiconductor device 111, a second region r2 (p-contact region) is provided near the first region r1 (SBD). When a reverse voltage is applied, a current flows through the SBD, which more effectively prevents the p-n body diode corresponding to the second region r2 from turning on. The second embodiment also provides a semiconductor device with improved characteristics.

[0047] For example, current is injected from the second electrode 52 into the pn diode via the silicide of the p-type contact, which makes it easier for the body diode near the p-type contact to turn on. In the semiconductor device 111, the p-type contact is provided in a portion where the SBD is dominant, thereby effectively suppressing the body diode operation.

[0048] 6, in the semiconductor device 111, the fourth semiconductor member 14 may also include a high-concentration region 14p and a low-concentration region 14q. As described with reference to FIGS. 2 and 3, the high-concentration region 14p is provided between the low-concentration region 14q and the second electrode 52. The impurity concentration of the first conductivity type in the high-concentration region 14p is higher than the impurity concentration of the first conductivity type in the low-concentration region 14q.

[0049] 7 is a schematic plan view illustrating a semiconductor device according to the second embodiment. As shown in FIG. 7, in a semiconductor device 112 according to the embodiment, the shape of the high-concentration region 14p is different from that in the semiconductor device 111. Except for this, the configuration of the semiconductor device 112 may be similar to the configuration of the semiconductor device 111.

[0050] In the semiconductor device 112, the position in the third direction D3 of at least a portion (e.g., portion 14pa) of the high concentration region 14p is between the position in the third direction D3 of the second portion 12b and the position in the third direction D3 of the third semiconductor portion 13c.

[0051] In the semiconductor device 112, for example, the current flowing through the third region r3 flows into the channel region via the portion 14pa. For example, a low on-resistance RonA becomes easier to obtain.

[0052] In the semiconductor device 112, the position of the third semiconductor portion 13 c in the second direction D2 is also between the position of the second semiconductor region 14 b in the second direction D2 and the position of the fifth portion region 11 e in the second direction D2. In the semiconductor device 112, it is also possible to provide a semiconductor device that can improve the characteristics.

[0053] For example, the third semiconductor portion 13c corresponds to a p-type contact region. The second semiconductor region 14b corresponds to an n-type contact region. A structure including the third semiconductor portion 13c and the second semiconductor region 14b constitutes one set. Multiple sets may be provided. The multiple sets may be arranged along the second direction D2. A structure including multiple sets constitutes one column. Multiple columns may be provided. The positions in the second direction D2 of the multiple sets included in one of the multiple columns may be different from the positions in the second direction D2 of the multiple sets included in another of the multiple columns. For example, the position in the second direction D2 of one of the multiple sets included in one of the multiple columns may be between the second direction D2 of one of the multiple sets included in another of the multiple columns and the second direction D2 of another of the multiple sets included in another of the multiple columns. The multiple sets may be arranged in a staggered manner.

[0054] In the first and second embodiments, for example, the first semiconductor member 11, the second semiconductor member 12, the third semiconductor member 13, and the fourth semiconductor member 14 contain SiC. The first semiconductor member 11, the second semiconductor member 12, the third semiconductor member 13, and the fourth semiconductor member 14 may contain at least one selected from the group consisting of 4H—SiC, 6H—SiC, and 3C—SiC. These semiconductor regions contain crystals. These semiconductor members may contain silicon. These semiconductor members may contain a compound semiconductor containing Ga.

[0055] For example, the impurities of the first conductivity type include at least one selected from the group consisting of N, P, and As. For example, the impurities of the second conductivity type include at least one selected from the group consisting of B, Al, and Ga.

[0056] In one example, the concentration of the impurity of the first conductivity type in the first semiconductor member 11 is, for example, 1×10 １４ cm －３ 1x10 or more １７ cm －３ In one example, the concentration of the impurity of the second conductivity type in the second semiconductor member 12 is, for example, 1×10 １６ cm －３ 1x10 or more ２０ cm －３ In one example, the concentration of the second conductivity type impurity in the third semiconductor member 13 is, for example, 1×10 １９ cm －３ 1x10 or more ２１ cm －３ In one example, the concentration of the impurity of the first conductivity type in the fourth semiconductor member 14 is, for example, 1×10 １９ cm －３ 1x10 or more ２１ cm －３ In one example, the concentration of the impurity of the first conductivity type in the fifth semiconductor member 15 is, for example, 1×10 １５ cm －３ 1x10 or more １８ cm －３ The above impurity concentration may be, for example, a substantial carrier concentration.

[0057] In an embodiment, information about the length and thickness can be obtained by electron microscopy, etc. Information about the composition of the material can be obtained by SIMS (Secondary Ion Mass Spectrometry) or EDX (Energy Dispersive X-ray spectroscopy), etc.

[0058] The embodiments may include the following technical solutions: (Technical Solution 1) A first semiconductor member including a first electrode, a second electrode, and a third electrode extending along a second direction intersecting a first direction from the first electrode to the second electrode, the first semiconductor member having a first conductivity type, the first semiconductor member including a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, the first partial region being provided between the first electrode and the third electrode in the first direction, a third direction from the first partial region to the second partial region intersecting a plane including the first direction and the second direction, the third partial region being provided between the first partial region and the third electrode in the first direction, the direction from the second partial region to the fourth partial region being along the second direction, and the direction from the fourth partial region to the fifth partial region being along the first direction, and the fifth partial region being in Schottky contact with the second electrode; a second semiconductor member of a second conductivity type, the second semiconductor member including a first portion and a second portion; and a third semiconductor member of the second conductivity type, the first portion being provided between the second partial region and the third semiconductor member in the first direction, a direction from at least a part of the third semiconductor member to the fifth partial region being along the second direction, the third semiconductor member including a first semiconductor portion, a second semiconductor portion, and a third semiconductor portion, a direction from the first semiconductor portion to the third semiconductor portion being along the third direction, a direction from the third semiconductor portion to the second semiconductor portion being along the second direction, the third semiconductor portion being electrically connected to the second electrode, and a third impurity concentration of the second conductivity type of the third semiconductor member being higher than a second impurity concentration of the second conductivity type of the second semiconductor member.a fourth semiconductor member of the first conductivity type, the fourth semiconductor member including a first semiconductor region and a second semiconductor region, the first semiconductor portion being provided between the first portion and the first semiconductor region in the first direction, the second semiconductor portion being provided between the first portion and the second semiconductor region in the first direction, the second semiconductor region being electrically connected to the second electrode, the second portion being provided between the third portion region and the first semiconductor portion, between the third portion region and the first semiconductor region, between the third portion region and the second semiconductor portion, and between the third portion region and the second semiconductor region in the third direction, a second semiconductor region length of the second semiconductor region in the third direction being longer than a first semiconductor region length of the first semiconductor region in the third direction, and a fourth impurity concentration of the first conductivity type in the fourth semiconductor member being higher than a first impurity concentration of the first conductivity type in the first semiconductor member.

[0059] (Technical Solution 2) The semiconductor device according to Technical Solution 1, wherein a second semiconductor portion length in the third direction of the second semiconductor portion is longer than a first semiconductor portion length in the third direction of the first semiconductor portion.

[0060] (Technical proposal 3) A semiconductor device described in Technical proposal 1 or 2, wherein a third thickness of the third semiconductor portion in the first direction is thinner than a first thickness of the first semiconductor portion in the first direction, and the third thickness is thinner than a second thickness of the second semiconductor portion in the first direction.

[0061] (Technical Solution 4) The semiconductor device according to Technical Solution 3, wherein the first thickness is 1.3 times or more and 2 times or less than the third thickness.

[0062] (Technical Solution 5) The semiconductor device according to any one of Technical Solutions 1 to 4, wherein at least a portion of the second semiconductor portion is provided between the third semiconductor portion and the fifth partial region in the second direction.

[0063] (Technical proposal 6) A semiconductor device described in any one of Technical proposals 1 to 4, wherein the position of the second semiconductor region in the second direction is between the position of the third semiconductor portion in the second direction and the position of the fifth portion region in the second direction.

[0064] (Technical proposal 7) A semiconductor device described in Technical proposal 6, wherein the fourth semiconductor member includes a high concentration region and a low concentration region, the high concentration region is provided between the low concentration region and the second electrode, and the impurity concentration of the first conductivity type in the high concentration region is higher than the impurity concentration of the first conductivity type in the low concentration region.

[0065] (Technical Solution 8) The semiconductor device according to any one of Technical Solutions 1 to 4, wherein at least a portion of the third semiconductor portion is provided between the second semiconductor portion and the fifth partial region in the second direction.

[0066] (Technical proposal 9) A semiconductor device described in any one of Technical proposals 1 to 4, wherein the position of the third semiconductor portion in the second direction is between the position of the second semiconductor region in the second direction and the position of the fifth portion region in the second direction.

[0067] (Technical proposal 10) A semiconductor device described in Technical proposal 9, wherein the fourth semiconductor member includes a high concentration region and a low concentration region, the high concentration region is provided between the low concentration region and the second electrode, and the impurity concentration of the first conductivity type in the high concentration region is higher than the impurity concentration of the first conductivity type in the low concentration region.

[0068] (Technical proposal 11) A semiconductor device described in Technical proposal 10, wherein the position of at least a portion of the high concentration region in the third direction is between the position of the second portion in the third direction and the position of the third semiconductor portion in the third direction.

[0069] (Technical proposal 12) The semiconductor device described in any one of Technical proposals 1 to 11, wherein the second electrode includes a first electrode portion and a second electrode portion, the first electrode portion is provided between the third semiconductor member and the second electrode portion, and between the fourth semiconductor member and the second electrode portion, and the first electrode portion includes silicide.

[0070] (Technical Solution 13) The semiconductor device according to any one of Technical Solutions 1 to 12, wherein the third semiconductor portion and the second semiconductor region are in ohmic contact with the second electrode.

[0071] (Technical Solution 14) The semiconductor device according to any one of Technical Solutions 1 to 13, wherein the second semiconductor region length is 1.1 times or more the first semiconductor region length.

[0072] (Technical proposal 15) A semiconductor device described in any one of Technical proposals 1 to 14, wherein a ratio of a third width of the third semiconductor portion along the second direction to a second width of the second semiconductor region along the second direction is 0.1 or more and 10 or less.

[0073] (Technical proposal 16) The semiconductor device described in any one of Technical proposals 1 to 15, wherein the second electrode includes a third electrode portion facing the fifth partial region, and the third electrode portion includes at least one selected from the group consisting of Ni, Ti, V, and Mo.

[0074] (Technical proposal 17) A semiconductor device described in any one of Technical proposals 1 to 16, further comprising a first insulating member including a first insulating region, wherein at least a portion of the first insulating region is provided between the third partial region and the third electrode.

[0075] (Technical Solution 18) The semiconductor device according to Technical Solution 17, wherein a portion of the first insulating member is provided between the fourth semiconductor member and the third electrode.

[0076] (Technical proposal 19) The semiconductor device according to any one of Technical proposals 1 to 18, further comprising a fifth semiconductor member of the first conductivity type, wherein the fifth semiconductor member is provided between the first electrode and the first semiconductor member in the first direction, and wherein a fifth impurity concentration of the first conductivity type in the fifth semiconductor member is higher than the first impurity concentration.

[0077] (Technical proposal 20) The semiconductor device according to any one of Technical proposals 1 to 19, wherein the first semiconductor member, the second semiconductor member, the third semiconductor member, and the fourth semiconductor member contain SiC.

[0078] According to the embodiment, a semiconductor device with improved characteristics can be provided.

[0079] 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 configurations of the elements included in the semiconductor device, such as the electrodes, semiconductor members, and insulating members, are 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 them from known ranges.

[0080] Furthermore, any combination of two or more elements of each specific example within the scope of technical feasibility is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0081] In addition, all semiconductor devices that can be implemented by a person skilled in the art 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 as long as they include the gist of the present invention.

[0082] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0083] 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 spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims.

[0084] 11-15: first to fifth semiconductor members, 11a-11e: first to fifth partial regions, 12a-12c: first to third portions, 13a-13c: first to third semiconductor portions, 13ax, 13bx: first and second semiconductor portion lengths, 13az, 13bz, 13cz: first, second and third thicknesses, 13cy: third width, 14a, 14b: first and second semiconductor regions, 14ax, 14bx: first and second semiconductor region lengths, 14by: second width, 14p: high concentration region, 14pa: part, 14q: low concentration region, 41: first insulating member, 41a: first insulating region, 51-53: first to third electrodes, 52a-52c: first to third electrode portions, 110 to 112: semiconductor device, D1 to D3: first to third directions, r1 to r3: first to third regions

Claims

1. A first semiconductor member having a first conductivity type, the first semiconductor member including a first partial region, a second partial region, a third partial region, a fourth partial region, and a fifth partial region, the first partial region being provided between the first electrode and the third electrode in the first direction, a third direction from the first partial region to the second partial region intersecting a plane including the first direction and the second direction, the third partial region being provided between the first partial region and the third electrode in the first direction, a direction from the second partial region to the fourth partial region being along the second direction, a direction from the fourth partial region to the fifth partial region being along the first direction, and the fifth partial region being in Schottky contact with the second electrode; and a second semiconductor member having a second conductivity type, the second semiconductor member including a first portion and a second portion. a third semiconductor member of the second conductivity type, the first portion being provided between the second partial region and the third semiconductor member in the first direction, a direction from at least a part of the third semiconductor member to the fifth partial region being along the second direction, the third semiconductor member including a first semiconductor portion, a second semiconductor portion and a third semiconductor portion, a direction from the first semiconductor portion to the third semiconductor portion being along the third direction, a direction from the third semiconductor portion to the second semiconductor portion being along the second direction, the third semiconductor portion being electrically connected to the second electrode, and a third impurity concentration of the second conductivity type of the third semiconductor member being higher than a second impurity concentration of the second conductivity type of the second semiconductor member;a fourth semiconductor member of the first conductivity type, the fourth semiconductor member including a first semiconductor region and a second semiconductor region, the first semiconductor portion being provided between the first portion and the first semiconductor region in the first direction, the second semiconductor portion being provided between the first portion and the second semiconductor region in the first direction, the second semiconductor region being electrically connected to the second electrode, the second portion being provided between the third portion region and the first semiconductor portion, between the third portion region and the first semiconductor region, between the third portion region and the second semiconductor portion, and between the third portion region and the second semiconductor region, a second semiconductor region length in the third direction of the second semiconductor region is longer than a first semiconductor region length in the third direction of the first semiconductor region, and a fourth impurity concentration of the first conductivity type in the fourth semiconductor member is higher than a first impurity concentration of the first conductivity type in the first semiconductor member.

2. The semiconductor device described in claim 1, wherein a third thickness of the third semiconductor portion in the first direction is thinner than a first thickness of the first semiconductor portion in the first direction, and the third thickness is thinner than a second thickness of the second semiconductor portion in the first direction.

3. The semiconductor device according to claim 1 or 2, wherein at least a portion of the second semiconductor portion is provided between the third semiconductor portion and the fifth partial region in the second direction.

4. A semiconductor device as described in claim 1 or 2, wherein the position of the second semiconductor region in the second direction is between the position of the third semiconductor portion in the second direction and the position of the fifth portion region in the second direction.

5. The semiconductor device according to claim 1 or 2, wherein at least a portion of the third semiconductor portion is provided between the second semiconductor portion and the fifth partial region in the second direction.

6. A semiconductor device as described in claim 1 or 2, wherein the position of the third semiconductor portion in the second direction is between the position of the second semiconductor region in the second direction and the position of the fifth portion region in the second direction.

7. The semiconductor device described in claim 6, wherein the fourth semiconductor member includes a high concentration region and a low concentration region, the high concentration region is provided between the low concentration region and the second electrode, and the impurity concentration of the first conductivity type in the high concentration region is higher than the impurity concentration of the first conductivity type in the low concentration region.

8. The semiconductor device described in claim 7, wherein a position of at least a portion of the high concentration region in the third direction is between a position of the second portion in the third direction and a position of the third semiconductor portion in the third direction.

9. The semiconductor device described in claim 1, wherein the second electrode includes a first electrode portion and a second electrode portion, the first electrode portion is provided between the third semiconductor member and the second electrode portion and between the fourth semiconductor member and the second electrode portion, and the first electrode portion includes a silicide.

10. The semiconductor device according to claim 1, wherein the first semiconductor member, the second semiconductor member, the third semiconductor member and the fourth semiconductor member comprise SiC.

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