Semiconductor devices

Abstract

The present invention provides a semiconductor device capable of improving characteristics. According to an embodiment, the semiconductor device includes a first conductive portion, a second conductive portion, a first semiconductor region, a third conductive portion, and a first insulating portion. The direction from the first conductive portion to the second conductive portion is along the first direction. The first semiconductor region is of the first conductive type. The first semiconductor region includes a first partial region, a second partial region, and a third partial region. The second direction from the first partial region to the second partial region intersects with the first direction. The third partial region is between the first partial region and the second conductive portion in the first direction. The third partial region includes an opposing surface opposite to the second conductive portion. The third partial region is in Schottky contact with the second conductive portion. The direction from the opposing surface to the third conductive portion is along the second direction. The first insulating portion includes a first insulating region. At least a portion of the first insulating region is between the opposing surface and the third conductive portion.

Description

[0001] This application is based on Japanese Patent Application No. 2020-025596 (filing date February 18, 2020) and Japanese Patent Application No. 2020-125240 (filing date July 22, 2020), and claims priority from these applications, and this application incorporates the entire contents of these applications by reference. Technical Field

[0002] Embodiments of the present invention relate to a semiconductor device. Background Art

[0003] In semiconductor devices, improvement in characteristics is desired. Summary of the invention

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

[0005] According to an embodiment of the present invention, a semiconductor device includes a first conductive portion, a second conductive portion, a first semiconductor region, a third conductive portion, and a first insulating portion. The direction from the first conductive portion to the second conductive portion is along the first direction. The first semiconductor region is of the first conductive type. The first semiconductor region includes a first partial region, a second partial region, and a third partial region. The second direction from the first partial region to the second partial region intersects the first direction. The third partial region is between the first partial region and the second conductive portion in the first direction. The third partial region includes an opposing surface that is opposite to the second conductive portion. The third partial region is in Schottky contact with the second conductive portion. The direction from the opposing surface to the third conductive portion is along the second direction. The first insulating portion includes a first insulating region. At least a portion of the first insulating region is between the opposing surface and the third conductive portion.

[0006] According to the semiconductor device having the above structure, it is possible to provide a semiconductor device having improved characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0008] Figure 2 This is a schematic cross-sectional view illustrating a portion of the semiconductor device according to the first embodiment.

[0009] Figure 3 This is a schematic diagram illustrating a part of the semiconductor device according to the first embodiment.

[0010] Figure 4 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0011] Figure 5 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0012] Figure 6 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0013] Figure 7 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0014] Figure 8 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0015] Fig. 9 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0016] Fig.10 It is a schematic cross-sectional view illustrating a semiconductor device according to a second embodiment.

[0017] Fig.11 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0018] Fig.12 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0019] (Explanation of symbols)

[0020] 11: semiconductor region; 11a~11e: 1st~5th partial regions; 12: 2nd semiconductor region; 41: 1st insulating portion; 41a, 41b: 1st and 2nd insulating regions; 42: 2nd insulating portion; 43: 3rd insulating portion; 51~55: 1st~5th conductive portions; 52p, 52q: 1st and 2nd conductive portions; 54L: wiring; 61: 1st component; 61L: wiring; 61T: terminal; 110~116, 120, 141, 141a: semiconductor device; Cn1: concentration; F1: opposing surface; c1, c2: 1st and 2nd conductive regions; pZ: position; r1, r2: 1st and 2nd regions. DETAILED DESCRIPTION

[0021] Hereinafter, various embodiments of the present invention will be described with reference to the drawings.

[0022] The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of the size between the parts, etc. are not necessarily the same as in reality. Even when the same part is shown, the size and ratio may be shown differently due to different drawings.

[0023] In the present specification and each drawing, regarding the drawings already shown, the same reference numerals are given to the same elements as those described above, and detailed descriptions thereof are appropriately omitted.

[0024] (First embodiment)

[0025] Figure 1 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0026] like Figure 1 As shown, the semiconductor device 110 according to the embodiment includes a first conductive portion 51 , a second conductive portion 52 , a third conductive portion 53 , a first semiconductor region 11 , and a first insulating portion 41 .

[0027] The direction from the first conductive portion 51 to the second conductive portion 52 is along the first direction. The first direction is referred to as the Z-axis direction. A direction perpendicular to the Z-axis direction is referred to as the X-axis direction. A direction perpendicular to the Z-axis direction and the X-axis direction is referred to as the Y-axis direction.

[0028] The first semiconductor region 11 is of a first conductivity type. The first conductivity type is one of an n-type and a p-type. Hereinafter, the first conductivity type is assumed to be an n-type.

[0029] The first semiconductor region 11 includes a first partial region 11a, a second partial region 11b, and a third partial region 11c. A second direction from the first partial region 11a to the second partial region 11b intersects the first direction. The second direction is, for example, the Y-axis direction.

[0030] The third partial region 11c is located between the first partial region 11a and the second conductive portion 52 in the first direction (Z-axis direction). The third partial region 11c includes an opposing surface F1 opposing the second conductive portion 52. The third partial region 11c is in Schottky contact with the second conductive portion 52.

[0031] The direction from the facing surface F1 to the third conductive portion 53 is along the second direction (for example, the Y-axis direction).

[0032] The first insulating portion 41 includes a first insulating region 41a. At least a portion of the first insulating region 41a is located between the opposing surface F1 and the third conductive portion 53. For example, the first insulating portion 41 (for example, the first insulating region 41a) electrically insulates the second conductive portion 52 from the third conductive portion 53. For example, the first insulating portion 41 (for example, the first insulating region 41a) electrically insulates the third partial region 11c from the third conductive portion 53.

[0033] For example, the direction from a part of the third partial region 11 c to the third conductive portion 53 may be along the second direction (eg, the Y-axis direction). The direction from at least a part of the second conductive portion 52 to the third conductive portion 53 may be along the second direction.

[0034] For example, the potential of the third conductive portion 53 is controlled to control the current flowing between the first conductive portion 51 and the second conductive portion 52. The first conductive portion 51 functions as a drain electrode, for example. The second conductive portion 52 functions as at least a portion of a source electrode. The third conductive portion 53 functions as a gate electrode, for example. The first insulating region 41a functions as a gate insulating film, for example. The semiconductor device 110 is, for example, a vertical transistor.

[0035] In the semiconductor device 110, a Schottky barrier is formed at the interface between the third partial region 11c and the second conductive portion 52. The thickness of the Schottky barrier (the distance in the Z-axis direction) can be controlled by the potential of the third conductive portion 53. When the Schottky barrier is thick, substantially no current flows. Thus, a cut-off state can be obtained. The potential of the third conductive portion 53 is controlled so that the Schottky barrier becomes thinner, for example, a tunnel current flows. Since the tunnel current flows, a conductive state can be obtained. According to the embodiment, a semiconductor device capable of improving characteristics can be provided.

[0036] For example, there is a vertical reference transistor having a pnp structure. In this case, the body diode generated at the contact portion of the source electrode includes a pn junction. Therefore, a long time is required for recovery.

[0037] On the other hand, in the embodiment, the region including the third partial region 11 c and the second conductive portion 52 (region including the Schottky contact) is a body diode. In the embodiment, the body diode is a Schottky diode, so the recovery speed can be increased.

[0038] In the reference example using the pnp structure, a region including the 1nth region, the pth region, and the 2nth region faces the gate electrode. Therefore, the gate length is long.

[0039] In contrast, in an embodiment, the third conductive portion 53 and the interface (e.g., the opposing surface F1) between the third partial region 11c and the second conductive portion 52 are opposed. Therefore, the gate length is short. As a result, the total gate charge (Qg) is small. The gate capacity is small. As a result, high-speed switching can be obtained. The loss is small. For example, the gate capacity (Cg) and the gate-drain capacity (Cgd) are reduced. As a result, the total gate charge (Qg) and the gate-drain charge (Qgd) are reduced. As a result, the loss of the gate driver can be reduced. For example, the switch can be made faster. For example, the turn-on loss and the turn-off loss can be suppressed.

[0040] The third conductive portion 53 may be opposed to the opposing surface F1 as well as to a portion of the third partial region 11c and a portion of the second conductive portion 52. For example, the thickness (length along the first direction, i.e., the Z-axis direction) of the third conductive portion 53 may be thin. The thickness of the third conductive portion 53 may be, for example, 100 nm or less.

[0041] In the reference example using the pnp structure, it is difficult to reduce the width (length in the Y-axis direction) of the source contact portion in consideration of misalignment, and therefore it is difficult to reduce the pitch between the plurality of source contacts.

[0042] In contrast, in the embodiment, a trench contact is not required. The second conductive portion 52 only needs to be provided with a structure that is in contact with the third partial region 11c. In the embodiment, the pitch between the plurality of source contacts can be easily reduced. For example, a small and low-resistance semiconductor device can be provided.

[0043] In the reference example using the pnp structure, there is a parasitic bipolar structure. For example, if the Hall current injected from the drain side becomes too large, avalanche damage is likely to occur.

[0044] In contrast, in the embodiment, there is no parasitic bipolar structure, so that, for example, a high avalanche withstand voltage can be obtained.

[0045] As described above, according to the embodiment, a semiconductor device having improved characteristics can be provided.

[0046] like Figure 1 As shown, the first semiconductor region 11 may include a fourth partial region 11d and a fifth partial region 11e. In the second direction (Y-axis direction), the second partial region 11b is located between the first partial region 11a and the fourth partial region 11d.

[0047] The fifth partial region 11e is provided between the first conductive portion 51 and the first partial region 11a. In this example, the fifth partial region 11e is also provided between the first conductive portion 51 and the second partial region 11b, and between the first conductive portion 51 and the fourth partial region 11d. The first conductive type impurity concentration in the fifth partial region 11e is higher than the first conductive type impurity concentration in the first partial region 11a. The fifth partial region 11e is, for example, n + The first to fourth partial regions 11 a to 11 d are, for example, n-regions. By providing the fifth partial region 11 e , a good electrical connection can be obtained between the first semiconductor region 11 and the first conductive portion 51 .

[0048] like Figure 1As shown, the semiconductor device 110 may also include a fourth conductive portion 54. The direction from the fourth partial region 11d to the fourth conductive portion 54 is along the first direction (Z-axis direction). The direction from at least a portion of the third partial region 11c to the fourth conductive portion 54 is along the second direction (for example, the Y-axis direction). The first insulating portion 41 includes a second insulating region 41b. The second insulating region 41b is located between at least a portion of the third partial region 11c and the fourth conductive portion 54 in the second direction (for example, the Y-axis direction). For example, the second insulating region 41b electrically insulates the third partial region 11c from the fourth conductive portion 54.

[0049] For example, the fourth conductive portion 54 is electrically connected to the second conductive portion 52. Alternatively, the fourth conductive portion 54 may be electrically connectable to the second conductive portion 52. In this example, the fourth conductive portion 54 is electrically connected to the second conductive portion 52 via the fifth conductive portion 55 by the wiring 54L. The wiring 54L may be provided with a terminal, and the terminal may be electrically connected to the second conductive portion 52 outside the semiconductor device 110.

[0050] The potential of the fourth conductive portion 54 is set to the potential (eg, source potential) of the second conductive portion 52. By providing the fourth conductive portion 54, the electric field in the first semiconductor region 11 can be controlled. For example, local concentration of the electric field can be suppressed. For example, high reliability can be easily obtained.

[0051] like Figure 1 As shown, in the first direction (Z-axis direction), the second conductive portion 52 is provided between the third partial region 11 c and at least a portion of the fifth conductive portion 55 . The fifth conductive portion 55 is electrically connected to the second conductive portion 52 and the fourth conductive portion 54 .

[0052] like Figure 1 As shown, the semiconductor device 110 may also include a second insulating portion 42. The third conductive portion 53 is located between the second partial region 11b and the fifth conductive portion 55 in the first direction (Z-axis direction). At least a portion of the second insulating portion 42 is located between the third conductive portion 53 and at least a portion of the fifth conductive portion 55 in the first direction (Z-axis direction). In this example, the third conductive portion 53 is located between the second insulating region 41b and at least a portion of the second insulating portion 42 in the first direction.

[0053] In an embodiment, the first semiconductor region 11 may also include at least one selected from the group consisting of silicon (Si), a nitride semiconductor (such as GaN), silicon carbide (SiC), and an oxide semiconductor (such as GaO). When the first semiconductor region 11 includes silicon, the first conductivity type impurity includes, for example, at least one selected from the group consisting of phosphorus, arsenic, and antimony.

[0054] In one example, when the third partial region 11c of the first semiconductor region 11 includes silicon, the second conductive portion 52 includes at least one selected from the group consisting of Ti, W, Mo, Ta, Zr, Al, Sn, V, Re, Os, Ir, Pt, Pd, Rh, Ru, Nb, Sr and Hf.

[0055] The third conductive portion 53 and the fourth conductive portion 54 may include, for example, at least one of polysilicon and metal. The fifth conductive portion 55 may include, for example, at least one selected from the group consisting of Al, Cu, Mo, W, Ta, Co, Ru, Ti, and Pt. The first conductive portion 51 may include, for example, Al, Cu, Mo, W, Ta, Co, Ru, Ti, and Pt.

[0056] Figure 2 This is a schematic cross-sectional view illustrating a portion of the semiconductor device according to the first embodiment.

[0057] Figure 2 It is an enlarged view of a region including the second conductive portion 52 .

[0058] like Figure 2 As shown, the third partial region 11c may also include a first region r1 and a second region r2. The first region r1 is located between the second region r2 and the second conductive portion 52 in the first direction (Z-axis direction). The concentration of the first conductive type impurity in the first region r1 is higher than the concentration of the first conductive type impurity in the second region r2. The first region r1 is, for example, n + The second region r2 is, for example, an n region. The first region r1 is thin. In one example, the thickness of the first region r1 along the first direction is greater than or equal to 1 nm and less than or equal to 20 nm.

[0059] By providing the first region r1 , for example, the thickness of the Schottky barrier (the length along the Z-axis direction) when the device is turned on can be reduced, thereby increasing the on-current.

[0060] like Figure 2 As shown, the second conductive portion 52 may include a first conductive region c1 and a second conductive region c2. The first conductive region c1 is located between the third partial region 11c and the second conductive region c2 in the first direction (Z-axis direction).

[0061] For example, the second conductive region c2 includes the first element. The third partial region 11c includes the second element. The first conductive region c1 includes a compound including the first element and the second element. For example, the second conductive region c2 includes the first metal element. The third partial region 11c includes silicon. The first conductive region c1 includes a silicide including the first metal element. The first metal element is, for example, at least one selected from the group consisting of Ti, W, Mo, Ta, Zr, Al, Sn, V, Re, Os, Ir, Pt, Pd, Rh, Ru, Nb, Sr, and Hf.

[0062] By providing the first conductive region c1 and the second conductive region c2 as described above, it is easy to form the first region r1 containing the first conductivity type impurity at a high concentration.

[0063] In one example, a metal layer serving as the second conductive portion 52 is formed on the silicon layer serving as the third partial region 11c. The metal layer contains impurities of the first conductive type. For example, by heat treatment or the like, a silicide region is formed on a portion of the metal layer on the silicon layer side. At this time, impurities contained in the silicon layer before the silicide region is formed move downward (toward the first conductive portion 51) from the silicide region. As a result, a region (e.g., the first region r1) containing impurities at a high concentration is formed in the portion of the third partial region 11c that is opposite to the silicide region.

[0064] In one example, a metal layer serving as the second conductive portion 52 may be formed on the silicon layer serving as the third partial region 11c, and impurities of the first conductive type may be introduced into a portion of the silicon layer via the metal layer. A region (e.g., the first region r1) containing impurities at a high concentration is formed in a portion of the silicon layer that is opposite to the metal layer. For example, the concentration of the impurities of the first conductive type in at least a portion of the second conductive region c2 may be higher than the concentration of the impurities in at least a portion of the first conductive region c1.

[0065] Figure 3 This is a schematic diagram illustrating a part of the semiconductor device according to the first embodiment.

[0066] Figure 3 The distribution of impurities in the region including the third partial region 11 c and the second conductive portion 52 is illustrated as an example. Figure 3 The horizontal axis is the position pZ in the Z-axis direction, and the vertical axis is the concentration Cn1 of the first conductivity type impurity.

[0067] like Figure 3 As shown, the impurity concentration Cn1 in the first region r1 is higher than the impurity concentration Cn1 in the second region r2.

[0068] Figure 4 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0069] like Figure 4 As shown, in the semiconductor device 111 of the embodiment, the structure of the first semiconductor region 11 is different from the structure of the first semiconductor region 11 in the semiconductor device 110 . The other structures of the semiconductor device 111 are the same as those of the semiconductor device 110 .

[0070] In the semiconductor device 111, the impurity concentration of the first conductivity type in the fourth partial region 11d is higher than the impurity concentration of the first conductivity type in the third partial region 11c. For example, the impurity concentration of the first conductivity type in the first partial region 11a is higher than the impurity concentration of the first conductivity type in the third partial region 11c. For example, the impurity concentration of the first conductivity type in the second partial region 11b is higher than the impurity concentration of the first conductivity type in the third partial region 11c. In the semiconductor device 111, a semiconductor device capable of improving characteristics can also be provided.

[0071] Figure 5 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0072] like Figure 5 As shown, in the semiconductor device 112 of the embodiment, the second insulating portion 42 is provided in each of the plurality of third conductive portions 53. For example, the fifth conductive portion 55 is connected to the fourth conductive portion 54 through two second insulating portions 42. The other structures in the semiconductor device 112 are the same as those in the semiconductor device 110. In the semiconductor device 112, a semiconductor device capable of improving characteristics can also be provided.

[0073] Figure 6 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0074] like Figure 6 As shown, in the semiconductor device 113 of the embodiment, Figure 1 The illustrated multiple structures are arranged in the Y-axis direction. In this example, the pitch of the multiple second conductive parts 52 is smaller than the pitch of the multiple fourth conductive parts 54. By using such a structure, for example, the resistance of the part including the Schottky contact when it is turned on can be reduced, and the on-resistance of the drift part (for example, the first semiconductor region 11) can be reduced.

[0075] In the semiconductor device 113, a plurality of second conductive portions 52 and a plurality of fourth conductive portions 54 are provided. The position of one second conductive portion 52 of the plurality of second conductive portions 52 in the second direction (Y-axis direction) and the position of another second conductive portion 52 of the plurality of second conductive portions 52 in the second direction are between the position of one fourth conductive portion 54 of the plurality of fourth conductive portions 54 in the second direction and the position of another fourth conductive portion 54 of the plurality of fourth conductive portions 54 in the second direction. The other fourth conductive portion 54 of the plurality of fourth conductive portions 54 is adjacent to the one fourth conductive portion 54 of the plurality of fourth conductive portions 54.

[0076] The semiconductor device 113 may be manufactured by separately manufacturing a portion including the fourth conductive portion 54 and a portion including the second conductive portion 52 and bonding the two portions to each other.

[0077] Alternatively, after forming the portion including the fourth conductive portion 54, the semiconductor layer may be regrown from the semiconductor region between the insulating portions to form the portion including the second conductive portion 52 and the third conductive portion 53. The regrowing may include, for example, lateral growth. The semiconductor device 113 may also be manufactured by such a method.

[0078] Figure 7 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0079] like Figure 7 As shown, the semiconductor device 114 of the embodiment includes the second semiconductor region 12. The other structures of the semiconductor device 114 may be the same as those of the semiconductor device 110.

[0080] The second semiconductor region 12 is of the second conductivity type (e.g., p-type). The second semiconductor region 12 is located between a portion of the third partial region 11c and the second conductive portion 52 in the first direction (the Z-axis direction). Another portion of the third partial region 11c is located between the second semiconductor region 12 and the first insulating region 41a in the second direction (e.g., the Y-axis direction).

[0081] For example, leakage current can be reduced by providing the second semiconductor region 12. When the second semiconductor region 12 includes silicon, the second conductivity type impurity includes, for example, at least one selected from the group consisting of boron, gallium, and indium.

[0082] Figure 8 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0083] like Figure 8As shown, in the semiconductor device 115 of the embodiment, in the Z-axis direction, one third conductive portion 53 overlaps with two regions of the first insulating portion 41 and the fourth conductive portion 54. The third insulating portion 43 is provided between the fourth conductive portion 54 and the third conductive portion 53. The other structures in the semiconductor device 115 may be the same as those in the semiconductor device 110. In the semiconductor device 115, a semiconductor device capable of improving characteristics can also be provided.

[0084] Fig. 9 This is a schematic cross-sectional view illustrating the semiconductor device according to the first embodiment.

[0085] like Fig. 9 As shown, the semiconductor device 116 of the embodiment may include a first member 61 in addition to the first conductive portion 51, the second conductive portion 52, the third conductive portion 53, the first semiconductor region 11, and the first insulating portion 41. The other structures of the semiconductor device 116 may be the same as those of the semiconductor device 110.

[0086] like Fig. 9 As shown, the first semiconductor region 11 includes the first to fourth partial regions 11a to 11d. In this example, the first semiconductor region 11 also includes the fifth partial region 11e. In the second direction (Y-axis direction), the second partial region 11b is between the first partial region 11a and the fourth partial region 11d. The direction from the fourth partial region 11d to the first member 61 is along the first direction (Z-axis direction). The direction from at least a portion of the third partial region 11c to the first member 61 is along the second direction (Y-axis direction). The first insulating portion 41 includes the second insulating region 41b. The second insulating region 41b is between at least a portion of the third partial region 11c and the first member 61 in the second direction (Y-axis direction).

[0087] For example, the first member 61 is electrically connected to the second conductive portion 52. Alternatively, the first member 61 can be electrically connected to the second conductive portion 52. For example, the first member 61 can be electrically connected to the second conductive portion 52 via the fifth conductive portion 55 using the wiring 61L. For example, the wiring 61L can be provided with a terminal 61T, and the terminal 61T and the second conductive portion 52 are connected outside the semiconductor device 116.

[0088] The resistivity of the first member 61 is higher than that of the fourth partial region 11d and lower than that of the second insulating region 41b. For example, the resistivity of the first member 61 is 5×10 7 Ωm or more and 8×10 11 Ωm or less.

[0089] According to the embodiment, for example, a small current can flow through the first member 61 when the device is turned off. Thus, for example, the electric field in the third partial region 11c can be made uniform. For example, the charge amount Qoss between the source and the drain can be reduced. Thus, for example, loss can be suppressed. For example, power consumption can be reduced. For example, the electric field applied to the gate insulating film can be reduced. For example, high reliability can be obtained. According to the embodiment, for example, a semiconductor device capable of improving characteristics can be provided.

[0090] The first member 61 may include the following various materials. For example, the first member 61 includes at least one selected from the group consisting of a first material, a second material, a third material, a fourth material, a fifth material, and a sixth material. The first material includes Si, N, and O, for example.

[0091] The second material includes, for example, Si, N, and O. The second material includes, for example, Si-N bonding, N-O bonding, and N-N bonding. The second material includes, for example, oxygen-doped SIPOS (Semi-insulating Poly-crystalline Silicon). The second material is, for example, a mixed material of SiH4, N2O, and N2.

[0092] The third material includes Si, N, and O. The third material includes, for example, Si—N bonds, N—H bonds, and N—N bonds. The third material is, for example, nitrogen-doped SIPOS. The third material is a mixed material of SiH 4 , NH 3 , and N 2 .

[0093] The fourth material includes, for example, Si, C, and the first element. The first element includes at least one selected from the group consisting of B and N. The fifth material includes, for example, Si, O, and the second element. The second element includes at least one selected from the group consisting of Fe, Au, Ni, Ta, W, and Ti. The sixth material includes, for example, the third element and the fourth element. The third element includes at least one selected from the group consisting of In, Al, and Ga. The fourth element includes at least one selected from the group consisting of P, As, B, Fe, Au, Ni, Ti, Ta, W, and Ti.

[0094] By using such a material, for example, the first member 61 can have an appropriate resistivity. Thus, as described above, a semiconductor device having improved characteristics can be provided.

[0095] (Second embodiment)

[0096] Fig.10 It is a schematic cross-sectional view illustrating a semiconductor device according to a second embodiment.

[0097] like Fig.10As shown, the semiconductor device 120 according to the embodiment includes a first conductive portion 51 , a second conductive portion 52 , a first semiconductor region 11 , a second semiconductor region 12 , a third conductive portion 53 , and a first insulating portion 41 .

[0098] The direction from the first conductive portion 51 to the second conductive portion 52 is along the first direction (Z-axis direction).

[0099] The first semiconductor region 11 is of a first conductivity type (e.g., n-type). The first semiconductor region 11 includes a first partial region 11a, a second partial region 11b, and a third partial region 11c. The second direction from the first partial region 11a to the second partial region 11b intersects the first direction. The second direction is, for example, the Y-axis direction. The third partial region 11c is located between the first partial region 11a and the second conductive portion 52 in the first direction (Z-axis direction).

[0100] The second semiconductor region 12 is provided between the third partial region 11c and the second conductive portion 52. The second semiconductor region 12 is of the second conductive type (e.g., p-type). The direction from at least a portion of the second semiconductor region 12 to the third conductive portion 53 is along the second direction (e.g., the Y-axis direction). The first insulating portion 41 includes a first insulating region 41a. At least a portion of the first insulating region 41a is between at least a portion of the second semiconductor region 12 and the third conductive portion 53.

[0101] The semiconductor device 120 is, for example, a pn-type transistor. The height of the potential barrier formed between the first semiconductor region 11 and the second semiconductor region 12 can be controlled by using the potential of the third conductive portion 53. In the semiconductor device 120, for example, the total gate charge (Qg) is also small. For example, the gate capacitance (Cg) and the capacitance between the gate and the drain (Cgd) are reduced. As a result, the total gate charge (Qg) and the charge between the gate and the drain (Qgd) are reduced. For example, the loss of the gate driver can be reduced. For example, the switching speed can be increased. For example, the turn-on loss and the turn-off loss can be suppressed. A semiconductor device capable of improving characteristics can be provided.

[0102] In the semiconductor device 120, the second conductive portion 52 may be continuous with the fifth conductive portion 55. The second conductive portion 52 may be integrated with the fifth conductive portion 55.

[0103] Fig.11 as well as Fig.12 is a schematic cross-sectional view of a semiconductor device according to an exemplary embodiment.

[0104] like Fig.11 as well as Fig.12As shown, in the semiconductor devices 141 and 141a of the embodiments, the second conductive portion 52 includes a first conductive portion 52p and a second conductive portion 52q. The second conductive portion 52q is located between the third partial region 11c and the first conductive portion 52p. For example, the direction from the second conductive portion 52q to a portion of the third partial region 11c is along the Y-axis direction. For example, the direction from the second conductive portion 52q to at least a portion of the third conductive portion 53 is along the Y-axis direction. In this example, the second conductive portion 52q is located between two portions of the third partial region 11c in the Y-axis direction. As in the semiconductor device 141a, the side surface of the second conductive portion 52q may be inclined relative to the Z-axis direction. In such a structure, a semiconductor device with improved characteristics can also be obtained. The structure of the second conductive portion 52 described with respect to the semiconductor device 141 can be applied to any semiconductor device of the first embodiment and the second embodiment.

[0105] The implementation method may also include the following technical solutions.

[0106] (Technical Solution 1)

[0107] A semiconductor device comprising:

[0108] a first conductive portion;

[0109] a second conductive portion, the direction from the first conductive portion to the second conductive portion being along the first direction;

[0110] a first semiconductor region of a first conductivity type, the first semiconductor region including a first partial region, a second partial region, and a third partial region, a second direction from the first partial region to the second partial region intersecting the first direction, the third partial region being between the first partial region and the second conductive portion in the first direction, the third partial region including an opposing surface opposing the second conductive portion, and the third partial region being in Schottky contact with the second conductive portion;

[0111] a third conductive portion, a direction from the opposing surface to the third conductive portion being along the second direction; and

[0112] A first insulating portion includes a first insulating region, at least a portion of which is located between the opposing surface and the third conductive portion.

[0113] (Technical Solution 2)

[0114] The semiconductor device according to claim 1, wherein:

[0115] The first insulating region electrically insulates the second conductive portion from the third conductive portion, and electrically insulates the third partial region from the third conductive portion.

[0116] (Technical Solution 3)

[0117] The semiconductor device according to technical solution 1 or 2, wherein:

[0118] A direction from a part of the third partial region to the third conductive portion is along the second direction,

[0119] A direction from at least a portion of the second conductive portion to the third conductive portion is along the second direction.

[0120] (Technical Solution 4)

[0121] The semiconductor device according to any one of claims 1 to 3, wherein:

[0122] The third part area includes the first area and the second area,

[0123] The first region is located between the second region and the second conductive portion in the first direction,

[0124] A concentration of the first conductivity type impurity in the first region is higher than a concentration of the first conductivity type impurity in the second region.

[0125] (Technical Solution 5)

[0126] The semiconductor device according to claim 4, wherein:

[0127] A thickness of the first region along the first direction is greater than or equal to 1 nm and less than or equal to 20 nm.

[0128] (Technical Solution 6)

[0129] The semiconductor device according to any one of claims 1 to 5, wherein:

[0130] The second conductive portion includes a first conductive region and a second conductive region,

[0131] The first conductive region is located between the first partial region and the second conductive region in the first direction.

[0132] The second conductive region includes a first element,

[0133] The third part region contains the second element,

[0134] The first conductive region contains a compound including the first element and the second element.

[0135] (Technical Solution 7)

[0136] The semiconductor device according to any one of claims 1 to 6, wherein:

[0137] The second conductive portion includes a first conductive region and a second conductive region,

[0138] The first conductive region is located between the third partial region and the second conductive region in the first direction.

[0139] The second conductive region includes a first metal element,

[0140] The third portion region comprises silicon,

[0141] The first conductive region includes a silicide containing the first metal element.

[0142] (Technical Solution 8)

[0143] The semiconductor device according to technical solution 7, wherein:

[0144] A concentration of the first conductivity type impurity in at least a portion of the second conductive region is higher than a concentration of the impurity in at least a portion of the first conductive region.

[0145] (Technical Solution 9)

[0146] The semiconductor device according to any one of claims 1 to 8, wherein:

[0147] The semiconductor device further comprises a fourth conductive portion,

[0148] The first semiconductor region further includes a fourth partial region,

[0149] In the second direction, the second partial region is between the first partial region and the fourth partial region,

[0150] A direction from the fourth partial region to the fourth conductive portion is along the first direction,

[0151] A direction from at least a portion of the third partial region to the fourth conductive portion is along the second direction,

[0152] The first insulating portion includes a second insulating region,

[0153] The second insulating region is located between the at least a portion of the third partial region and the fourth conductive portion in the second direction.

[0154] (Technical Solution 10)

[0155] The semiconductor device according to technical solution 9, wherein:

[0156] The fourth conductive portion is electrically connected to the second conductive portion.

[0157] (Technical Solution 11)

[0158] The semiconductor device according to technical solution 9 or 10, wherein:

[0159] The semiconductor device further comprises a fifth conductive portion,

[0160] The second conductive portion is provided between the third partial region and at least a portion of the fifth conductive portion in the first direction.

[0161] The fifth conductive portion is electrically connected to the second conductive portion and the fourth conductive portion.

[0162] (Technical Solution 12)

[0163] The semiconductor device according to technical solution 11, wherein:

[0164] The semiconductor device further includes a second insulating portion.

[0165] The third conductive portion is located between the second partial region and the fifth conductive portion in the first direction,

[0166] At least a portion of the second insulating portion is located between at least a portion of the third conductive portion and the fifth conductive portion in the first direction.

[0167] (Technical Solution 13)

[0168] The semiconductor device according to any one of claims 9 to 12, comprising:

[0169] a plurality of the second conductive parts; and

[0170] The plurality of fourth conductive parts,

[0171] The position of one of the multiple second conductive parts in the second direction and the position of another of the multiple second conductive parts in the second direction are between the position of one of the multiple fourth conductive parts in the second direction and the position of another of the multiple fourth conductive parts in the second direction, and the other of the multiple fourth conductive parts is adjacent to the one of the multiple fourth conductive parts.

[0172] (Technical Solution 14)

[0173] The semiconductor device according to any one of claims 9 to 13, wherein:

[0174] The concentration of the first conductivity type impurities in the fourth partial region is higher than the concentration of the first conductivity type impurities in the third partial region.

[0175] (Technical Solution 15)

[0176] The semiconductor device according to any one of claims 1 to 14, wherein:

[0177] The first semiconductor region includes a fifth partial region,

[0178] The fifth partial region is disposed between the first conductive portion and the first partial region,

[0179] The concentration of the first conductivity type impurities in the fifth partial region is higher than the concentration of the first conductivity type impurities in the first partial region.

[0180] (Technical Solution 16)

[0181] The semiconductor device according to any one of claims 1 to 15, wherein:

[0182] The semiconductor device further includes a second semiconductor region of a second conductivity type.

[0183] The second semiconductor region is located between a portion of the third partial region and the second conductive portion in the first direction.

[0184] Another portion of the third partial region is located between the second semiconductor region and the first insulating region in the second direction.

[0185] (Technical Solution 17)

[0186] The semiconductor device according to any one of claims 1 to 8, wherein:

[0187] The semiconductor device further comprises a first member,

[0188] The first semiconductor region further includes a fourth partial region,

[0189] In the second direction, the second partial region is between the first partial region and the fourth partial region,

[0190] A direction from the fourth partial region to the first member is along the first direction,

[0191] from at least a portion of the third partial region toward the first member along the second direction,

[0192] The first insulating portion includes a second insulating region,

[0193] The second insulating region is located between the at least a portion of the third partial region and the first member in the second direction,

[0194] The first member is electrically connected to the fourth partial region,

[0195] The first member is electrically connected to the second conductive portion, or can be electrically connected to the second conductive portion.

[0196] The resistivity of the first member is higher than the resistivity of the fourth partial region and lower than the resistivity of the second insulating region.

[0197] (Technical Solution 18)

[0198] The semiconductor device according to any one of claims 1 to 8, wherein:

[0199] The semiconductor device further comprises a first member,

[0200] A direction from the second partial region to the first member is along the first direction,

[0201] from at least a portion of the third partial region toward the first member along the second direction,

[0202] The first insulating portion includes a second insulating region,

[0203] The second insulating region is located between the at least a portion of the third partial region and the first member in the second direction,

[0204] The first member is electrically connected to the fourth partial region,

[0205] The first member is electrically connected to the second conductive portion, or can be electrically connected to the second conductive portion.

[0206] The first member includes at least one selected from the group consisting of a first material, a second material, a third material, a fourth material, a fifth material, and a sixth material.

[0207] The first material includes Si, N and O,

[0208] The second material includes Si—N bonds, N—O bonds, and N—N bonds.

[0209] The third material includes Si-N bonding, N-H bonding, and N-N bonding.

[0210] The fourth material includes Si, C, and a first element, wherein the first element includes at least one selected from the group consisting of B and N,

[0211] The fifth material includes Si, O, and a second element, wherein the second element includes at least one selected from the group consisting of Fe, Au, Ni, Ta, W, and Ti.

[0212] The sixth material includes a third element and a fourth element, the third element includes at least one selected from the group consisting of In, Al and Ga, and the fourth element includes at least one selected from the group consisting of P, As, B, Fe, Au, Ni, Ti, Ta, W and Ti.

[0213] (Technical Solution 19)

[0214] A semiconductor device comprising:

[0215] a first conductive portion;

[0216] a second conductive portion, the direction from the first conductive portion to the second conductive portion being along the first direction;

[0217] a first semiconductor region of a first conductive type, the first semiconductor region comprising a first partial region, a second partial region, and a third partial region, a second direction from the first partial region to the second partial region intersecting the first direction, and the third partial region being between the first partial region and the second conductive portion in the first direction;

[0218] a second semiconductor region of a second conductivity type, disposed between the third partial region and the second conductive portion;

[0219] a third conductive portion, a direction from at least a portion of the second semiconductor region to the third conductive portion being along the second direction; and

[0220] A first insulating portion includes a first insulating region, at least a portion of the first insulating region being located between the at least a portion of the second semiconductor region and the third conductive portion.

[0221] According to the embodiment, a semiconductor device having improved characteristics can be provided.

[0222] In this specification, "nitride semiconductor" is included in B x In y Al z Ga 1－x－y－zIn the chemical formula of N (0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z≤1), semiconductors of all compositions in which the composition ratios x, y, and z are changed within respective ranges. Furthermore, in the above chemical formula, examples of group V elements other than N (nitrogen), examples of various elements added to control various physical properties such as conductivity type, and examples of various elements not intentionally included are also included in the "nitride semiconductor".

[0223] The embodiments of the present invention are described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific structure of each element such as the conductive part, semiconductor region, insulating part and wiring included in the semiconductor device is included in the scope of the present invention as long as it can be appropriately selected by a person skilled in the art from the known range to implement the present invention in the same manner and obtain the same effect.

[0224] Furthermore, examples in which two or more elements of the specific examples are combined within a technically feasible range are also included in the scope of the present invention as long as the gist of the present invention is included.

[0225] In addition, as embodiments of the present invention, all semiconductor devices that can be implemented by appropriately changing the design of the above-mentioned semiconductor device by a person skilled in the art also belong to the scope of the present invention as long as they include the gist of the present invention.

[0226] In addition, within the scope of the concept of the present invention, a person skilled in the art can conceive of various changes and modifications, and it is understood that these changes and modifications belong to the scope of the present invention.

[0227] Several embodiments of the present invention have been described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their variations are included in the scope and gist of the invention, and are included in the invention described in the patent claims and the scope equivalent thereto.

Claims

1. A semiconductor device comprising: a first conductive portion; a second conductive portion, the direction from the first conductive portion to the second conductive portion being along the first direction; a first semiconductor region of a first conductivity type, the first semiconductor region including a first partial region, a second partial region, and a third partial region, a second direction from the first partial region to the second partial region intersecting the first direction, the third partial region being between the first partial region and the second conductive portion in the first direction, the third partial region including an opposing surface opposing the second conductive portion, and the third partial region being in Schottky contact with the second conductive portion; a third conductive portion, a direction from the opposing surface to the third conductive portion being along the second direction; and a first insulating portion including a first insulating region, at least a portion of the first insulating region being located between the opposing surface and the third conductive portion, The second conductive portion includes a first conductive region and a second conductive region, The first conductive region is located between the third partial region and the second conductive region in the first direction. The second conductive region includes a first metal element, The third portion region comprises silicon, The first conductive region contains a silicide including the first metal element. The first metal element includes at least one selected from the group consisting of Mo, Ta, Zr, Sn, V, Re, Os, Ir, Rh, Ru, Nb, Sr, and Hf, A concentration of the first conductivity type impurity in at least a portion of the second conductive region is higher than a concentration of the impurity in at least a portion of the first conductive region.

2. The semiconductor device according to claim 1, wherein A direction from a part of the third partial region to the third conductive portion is along the second direction, A direction from at least a portion of the second conductive portion to the third conductive portion is along the second direction.

3. The semiconductor device according to claim 1 or 2, wherein: The semiconductor device further comprises a fourth conductive portion, The first semiconductor region further includes a fourth partial region, In the second direction, the second partial region is between the first partial region and the fourth partial region, A direction from the fourth partial region to the fourth conductive portion is along the first direction, A direction from at least a portion of the third partial region to the fourth conductive portion is along the second direction, The first insulating portion includes a second insulating region, The second insulating region is located between the at least a portion of the third partial region and the fourth conductive portion in the second direction.

4. The semiconductor device according to claim 3, wherein: The fourth conductive portion is electrically connected to the second conductive portion.

5. The semiconductor device according to claim 3, wherein: The semiconductor device further comprises a fifth conductive portion, The second conductive portion is provided between the third partial region and at least a portion of the fifth conductive portion in the first direction. The fifth conductive portion is electrically connected to the second conductive portion and the fourth conductive portion.

6. The semiconductor device according to claim 5, wherein: The semiconductor device further includes a second insulating portion. The third conductive portion is located between the second partial region and the fifth conductive portion in the first direction, At least a portion of the second insulating portion is located between at least a portion of the third conductive portion and the fifth conductive portion in the first direction.

7. The semiconductor device according to claim 3, comprising: a plurality of the second conductive parts; and A plurality of said fourth conductive parts, The position of one of the multiple second conductive parts in the second direction and the position of another of the multiple second conductive parts in the second direction are between the position of one of the multiple fourth conductive parts in the second direction and the position of another of the multiple fourth conductive parts in the second direction, and the other of the multiple fourth conductive parts is adjacent to the one of the multiple fourth conductive parts.

8. The semiconductor device according to claim 3, wherein: The concentration of the first conductivity type impurities in the fourth partial region is higher than the concentration of the first conductivity type impurities in the third partial region.

9. The semiconductor device according to claim 1 or 2, wherein: The first semiconductor region includes a fifth partial region, The fifth partial region is disposed between the first conductive portion and the first partial region. The concentration of the first conductivity type impurities in the fifth partial region is higher than the concentration of the first conductivity type impurities in the first partial region.

10. The semiconductor device according to claim 1 or 2, wherein: The semiconductor device further includes a second semiconductor region of a second conductivity type. The second semiconductor region is located between a portion of the third partial region and the second conductive portion in the first direction. Another portion of the third partial region is located between the second semiconductor region and the first insulating region in the second direction.

11. A semiconductor device comprising: a first conductive portion; a second conductive portion, the direction from the first conductive portion to the second conductive portion being along the first direction; a first semiconductor region of a first conductive type, the first semiconductor region comprising a first partial region, a second partial region, and a third partial region, a second direction from the first partial region to the second partial region intersecting the first direction, and the third partial region being between the first partial region and the second conductive portion in the first direction; a second semiconductor region of a second conductivity type, disposed between the third partial region and the second conductive portion; a third conductive portion, a direction from at least a portion of the second semiconductor region to the third conductive portion being along the second direction; and a first insulating portion including a first insulating region, at least a portion of the first insulating region being between the at least a portion of the second semiconductor region and the third conductive portion, The second conductive portion includes a first conductive region and a second conductive region, The first conductive region is located between the third partial region and the second conductive region in the first direction. The second conductive region includes a first metal element, The third portion region comprises silicon, The first conductive region contains a silicide including the first metal element. The first metal element includes at least one selected from the group consisting of Mo, Ta, Zr, Sn, V, Re, Os, Ir, Rh, Ru, Nb, Sr, and Hf, A concentration of the first conductivity type impurity in at least a portion of the second conductive region is higher than a concentration of the impurity in at least a portion of the first conductive region.

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