Semiconductor device

Abstract

This semiconductor device (100) is provided with: a semiconductor element (7); a case (1) that has an accommodation space (17) for accommodating the semiconductor element (7), and an edge portion (16) defining an opening (12) of the accommodation space (17); a lid member (2) that covers the opening (12), and has an outer peripheral portion (18) with a protrusion (3) that protrudes in a direction from the opening (12) toward the outside of the accommodation space (17), and an inner peripheral portion (19) located on an inner peripheral side relative to the outer peripheral portion (18); and an adhesive (15) that bonds the edge portion (16) to the outer peripheral portion (18).

Description

Semiconductor device

[0001] This disclosure relates to a semiconductor device.

[0002] Conventional semiconductor devices cover the opening of a case containing semiconductor elements with a lid portion and adhere the case and the lid portion with an adhesive member to prevent moisture and foreign matter from entering the case from the outside (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2023-88146 (FIG. 11)

[0004] For example, due to changes in the ambient temperature environment or heat generation of semiconductor elements, etc., temperature changes may occur in the semiconductor device. In the above conventional semiconductor device, the amount of deformation due to thermal expansion or thermal contraction of the case and the lid portion when a temperature change occurs may be different, and as a result, there has been a risk that the adhesive member is strained and the adhesive member peels off.

[0005] This disclosure has been made to solve the above problems, and aims to obtain a semiconductor device in which the adhesive that adheres the case and the lid member is difficult to peel off even when a temperature change occurs.

[0006] The semiconductor device according to this disclosure includes a semiconductor element, a case having an accommodation space for accommodating the semiconductor element and having an edge portion forming an opening of the accommodation space, a lid member having an outer peripheral portion covering the opening and having a convex portion protruding in a direction from the opening toward the outside of the accommodation space, and an inner peripheral portion located on the inner peripheral side of the outer peripheral portion, and an adhesive for adhering the edge portion and the outer peripheral portion.

[0007] According to this disclosure, it is possible to make the adhesive that adheres the case and the lid member difficult to peel off even when a temperature change occurs.

[0008] This is a top view of the semiconductor device in Embodiment 1. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 1. This is a longitudinal cross-sectional view of the lid member in Embodiment 1. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 2. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 3. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 4. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 5. This is a cross-sectional view of the section A-A in Figure 1 in Embodiment 6.

[0009] Embodiment 1. In the following description, for the sake of ease of explanation, the X-Y-Z axes shown in the figures will be referred to as appropriate. First, the configuration of the semiconductor device 100 in Embodiment 1 will be described. Figure 1 is a top view of the semiconductor device 100 in Embodiment 1. Figure 2 is a cross-sectional view of Embodiment 1 along the cross-sectional line A-A in Figure 1. In Figure 2, the X-Y-Z axes are shown with the direction from left to right on the page corresponding to the +X direction and the direction from front to back on the page corresponding to the +Y direction, in line with the vicinity of the lid member 2. Therefore, it should be noted that the direction in the XY plane does not coincide with the X-Y-Z axes near the location where the hole 11 of the case 1 is formed.

[0010] In Figures 1 and 2, the semiconductor device 100 comprises a case 1 having a housing space 17 for housing a semiconductor element 7, a lid member 2 covering an opening 12 formed in the upper part of the case 1, an adhesive 15 for bonding the case 1 and the lid member 2, and a semiconductor element 7 installed in the housing space 17 inside the case 1. Terminals 5 are installed from the inside to the outside of the case 1, and the terminals 5 and the semiconductor element 7 are electrically connected by internal wiring 6. The semiconductor element 7 is fixed and mounted on a substrate 9 by a bonding material 8. The substrate 9 is installed so that a part of it enters the case 1 through a substrate opening 13 formed in the lower part of the case 1, and the other part of it exits the case 1. The semiconductor element 7 is covered with a sealing material 10 inside the housing space 17.

[0011] Case 1 has side walls surrounding a housing space 17 in the XY plane, and has an opening 12 on the +Z side, i.e., the upper part of Case 1, and a substrate opening 13 on the -Z side, i.e., the lower part of Case 1. The opening 12 and the substrate opening 13 face each other. An edge portion 16 is formed on the inner circumference of the upper side wall of Case 1 by forming a stepped shape. Holes 11 are formed at each of the four corners in the XY plane of the lower part of Case 1. Case 1 is made of a resin material such as polyphenylene sulfide (PPS) or polybutylene terephthalate (PBT).

[0012] Here, the opening 12 is the end of the housing space 17 on the +Z direction side, and refers to the opening portion in the XY plane parallel to the upper surface of the edge 16. Since the opening 12 is surrounded by the edge 16, it can be said that the opening 12 is formed by the edge 16. The substrate opening 13 is the end of the housing space 17 on the -Z direction side, and refers to the opening portion in the XY plane parallel to the lower end surface of the case 1. In other words, the housing space 17 is the space surrounded by the side wall of the case 1, and refers to the space from the opening 12 to the substrate opening 13. A part of the terminals 5, internal wiring 6, semiconductor elements 7, bonding material 8, a part of the substrate 9, and sealing material 10 are housed in the housing space 17.

[0013] The holes 11 are, for example, screw holes used to fix the semiconductor device 100 to a heat sink (not shown). The heat sink is a plate for dissipating heat generated from the semiconductor element 7 housed inside the case 1 to the outside of the case 1. The heat sink is positioned to contact the -Z side surface of the substrate 9, that is, the surface opposite to the surface on which the semiconductor element 7 is mounted, and the heat sink and the case 1 are fixed by screws inserted into the holes 11. The heat sink is an example of a heat dissipation member.

[0014] Figure 3 is a longitudinal cross-sectional view of the lid member 2 in Embodiment 1. As shown in Figures 2 and 3, the lid member 2 has an outer peripheral portion 18 having a protrusion 3 that projects in the +Z direction, i.e., toward the outside of the housing space 17 from the opening 12, and an inner peripheral portion 19 located on the inner side of the outer peripheral portion 18. Here, the outer peripheral portion 18 is the part of the lid member 2 where the protrusion 3 is formed, and more specifically, it refers to the portion from the outermost surface of the lid member 2 to the innermost surface of the protrusion 3 in the X direction. The inner peripheral portion 19 refers to the portion of the lid member 2 other than the outer peripheral portion 18. The outer peripheral portion 18 of the lid member 2 is positioned to rest on the edge portion 16 of the case 1, and the outer peripheral portion 18 and the edge portion 16 are bonded together with adhesive 15. It is desirable that the lid member 2 be formed from the same material as the case 1, but it may also be formed from a different material. When the lid member 2 is formed from a different material than the case 1, it is preferable that the elastic modulus of the lid member 2 be less than or equal to that of the case 1, i.e., that the lid member 2 be formed from a material that is more easily deformable than the material of the case 1.

[0015] The protrusion 3 has an inclined portion 4 on its outer circumference, formed such that the cross-sectional area in the XY plane, i.e., the plane parallel to the opening 12, decreases as it moves toward the +Z direction, i.e., as it moves away from the opening 12. The inclined portion 4 is formed to extend to the outermost outer circumference 20 of the outer circumference 18. Due to the formation of the inclined portion 4, the thickness of the outermost outer circumference 20 of the outer circumference 18 is thinner than the thickness of the inner circumference 19. The protrusion 3 is formed to continuously wrap around the outer circumference of the lid member 2, and the inclined portion 4 is formed to continuously wrap around along the protrusion 3.

[0016] The adhesive 15 adheres the case 1 and the lid member 2. More specifically, the adhesive 15 adheres the edge 16 of the case 1 and the outer circumference 18 of the lid member 2. As the material of the adhesive 15, for example, a material containing silicone resin, a material containing epoxy resin, a material containing acrylic resin, or silicon dioxide (SiO2) ２ Materials containing ceramics such as ) are used. Furthermore, it is desirable that the adhesive 15 be made of a material with a lower elastic modulus than that used in case 1.

[0017] As shown in Figure 2, terminal 5 has an L-shaped cross-section in the XZ plane and is integrally molded with case 1. Terminal 5 is electrically connected to semiconductor element 7 via internal wiring 6. The portion of terminal 5 that protrudes outside case 1 is electrically connected to external wiring (not shown).

[0018] The substrate 9 has, in order from the -Z direction side, i.e., the bottom side, a metal plate 9a, an insulating layer 9b, and a conductive pattern 9c. The +Z direction side, i.e., the top surface, of the metal plate 9a is covered by the insulating layer 9b. The conductive pattern 9c is provided on the insulating layer 9b at the locations where the semiconductor elements 7 are to be mounted. The semiconductor elements 7 are mounted on the conductive pattern 9c via a bonding material 8. The case 1 and the substrate 9 are bonded together by an adhesive 14. With the case 1 and the substrate 9 bonded together, the top surface of the substrate 9, i.e., the surface on which the semiconductor elements 7 are mounted, is located inside the case 1, and the bottom surface of the substrate 9, i.e., the surface opposite to the surface on which the semiconductor elements 7 are mounted, extends outside the case 1 through the substrate opening 13. More specifically, the -Z direction side of the metal plate 9a of the substrate 9 extends outside the case 1 through the substrate opening 13.

[0019] The thickness of the metal plate 9a is preferably 0.5 mm or more. The insulating layer 9b is preferably made of resin, but may also be made of an inorganic material such as ceramic. The conductive pattern 9c is made of metal, for example. The bonding material 8 is made of a conductive material, such as solder, Ag paste, or sintered paste.

[0020] As with adhesive 15, various materials can be used for adhesive 14.

[0021] The semiconductor element 7 is mounted on a conductive pattern 9c of a substrate 9 via a bonding material 8. The semiconductor element 7 is, for example, a power semiconductor element such as an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or a Schottky barrier diode. Alternatively, the semiconductor element 7 may be an RC-IGBT (Reverse-Conducting IGBT) in which the IGBT and freewheeling diode are formed within a single semiconductor substrate. The semiconductor element 7 is formed from silicon (Si) or a wide-bandgap semiconductor. Examples of wide-bandgap semiconductors include silicon carbide, gallium nitride, gallium oxide, and diamond. Although only one semiconductor element 7 is shown in Figure 2, multiple semiconductor elements 7 may be mounted.

[0022] The internal wiring 6 electrically connects the terminal 5 to the semiconductor element 7, and the terminal 5 to the conductive pattern 9c. More specifically, within the housing space 17, one end of the internal wiring 6 is joined to the terminal 5, and the other end of the internal wiring 6 is joined to the electrode of the semiconductor element 7 or the conductive pattern 9c. As the internal wiring 6, for example, a metal wire made of aluminum or the like is used, but it is not limited to a metal wire; a metal frame or metal ribbon made from a thin metal plate may also be used.

[0023] The sealing material 10 seals the terminals 5, internal wiring 6, semiconductor element 7, bonding material 8, and substrate 9 within the housing space 17 of the case 1. The sealing material 10 is, for example, a resin containing silicone gel, and may also be a thermosetting resin such as epoxy resin.

[0024] Here, we will explain the situation when temperature changes occur in a conventional semiconductor device that does not have a protrusion 3 on the lid member 2. Temperature changes occur, for example, due to changes in the ambient temperature environment in which the semiconductor device is installed, or due to heat generation by the semiconductor element 7. When a temperature change occurs in the semiconductor device, the case 1 and the lid member 2 deform due to thermal expansion or contraction. The amount of deformation at this time may differ between the case 1 and the lid member 2. This causes strain in the adhesive 15. Furthermore, if the terminal 5 is integrally molded with the case 1, or if the case 1 is fixed to a heat sink, the behavior due to thermal expansion or contraction when a temperature change occurs becomes more complex. For this reason, even if the linear expansion coefficients of the case 1 and the lid member 2 are the same, the deformation due to thermal expansion or contraction will differ between the case 1 and the lid member 2, making it difficult to eliminate the strain that occurs in the adhesive 15. If strain occurs in the adhesive 15, there is a risk that the adhesive 15 will peel off. However, if stress concentration near the outer circumference 18, where the lid member 2 is bonded to the case 1, can be alleviated, the strain generated in the adhesive 15 can be reduced, making the adhesive 15 less likely to peel off.

[0025] The semiconductor device 100 in Embodiment 1 includes a semiconductor element 7, a case 1 having a housing space 17 for housing the semiconductor element 7 and an edge portion 16 forming an opening 12 of the housing space 17, a lid member 2 having an outer peripheral portion 18 that covers the opening 12 and has a protrusion 3 projecting outward from the opening 12 toward the outside of the housing space 17, and an inner peripheral portion 19 located on the inner side of the outer peripheral portion 18, and an adhesive 15 for bonding the edge portion 16 and the outer peripheral portion 18. Due to the protrusion 3, the maximum thickness of the outer peripheral portion 18 in the Z-axis direction is greater than the maximum thickness of the inner peripheral portion 19 in the Z-axis direction. As a result, the inner peripheral portion 19 is more easily deformed than the outer peripheral portion 18 which is bonded to the case 1 via the adhesive 15. In other words, when the lid member 2 deforms, the more easily deformable inner peripheral portion 19 deforms, which can alleviate the concentration of stress on the outer peripheral portion 18 which is bonded to the case 1. By alleviating the stress concentration on the outer peripheral portion 18, the strain generated in the adhesive 15 can be reduced. This configuration makes it difficult for the adhesive 15 that bonds the case 1 and the lid member 2 to peel off even when temperature changes occur.

[0026] Furthermore, in Embodiment 1, the lid member 2 has an inclined portion 4 on its outer circumference, formed such that the cross-sectional area of ​​the protrusion 3 on the plane parallel to the opening 12 decreases as it moves away from the opening 12. This increases the contact area between the lid member 2 and the adhesive 15, and also increases the thickness of the adhesive 15, thereby improving the allowable stress of the adhesive 15. As a result, the adhesive 15 can be made less likely to peel off.

[0027] Furthermore, in Embodiment 1, the protrusion 3 formed on the lid member 2 is formed to continuously wrap around the outer circumference of the lid member 2, and the inclined portion 4 is formed to continuously wrap around along the protrusion 3. This configuration reduces the strain that occurs in the adhesive 15 around the entire circumference of the lid member 2. As a result, the adhesive 15 can be made less likely to peel off. In addition, since the protrusion 3 functions as a reinforcing rib, it suppresses warping of the lid member 2 itself and suppresses deformation when force is applied to the lid member 2. For example, when a thermosetting adhesive is used as the adhesive 15, force may be applied to the lid member 2 due to the shrinkage of the adhesive 15 during heat curing, but the formation of the protrusion 3 on the lid member 2 suppresses deformation of the lid member 2.

[0028] Furthermore, in Embodiment 1, the inclined portion 4 of the lid member 2 is formed to extend to the outermost outer periphery 20 of the outer peripheral portion 18, and the thickness of the outermost outer peripheral portion 20 of the outer peripheral portion 18 is formed to be thinner than the thickness of the inner peripheral portion 19. Therefore, the adhesive 15 is more likely to flow down the inclined surface of the inclined portion 4 into the storage space 17, and the adhesive 15 is more likely to flow between the edge portion 16 of the case 1 and the lid member 2. As the adhesive 15 flows between the edge portion 16 and the lid member 2, the bonding area between the case 1 and the lid member 2 by the adhesive 15 increases. With this configuration, the adhesive 15 can be made less likely to peel off.

[0029] Furthermore, in Embodiment 1, the semiconductor device includes a substrate 9 on which semiconductor elements 7 are mounted. The case 1 has a substrate opening 13 located opposite the opening 12. The side of the substrate 9 on which the semiconductor elements 7 are mounted is located inside the case 1, while the side of the substrate 9 opposite to the side on which the semiconductor elements 7 are mounted extends outside the case 1 through the substrate opening 13. The semiconductor device 100 is fixed to a heat sink (not shown) using screws or the like through holes 11 in the case 1, with thermal grease applied to the back surface of the metal plate 9a. Because the side of the substrate 9 opposite to the side on which the semiconductor elements 7 are mounted, i.e., the back surface of the metal plate 9a, extends outside the case 1 through the substrate opening 13, when fixing the semiconductor device 100 to the heat sink, the metal plate 9a contacts and presses against the heat sink before the case 1, causing the thermal grease applied to the back surface of the metal plate 9a to spread. As a result, the thickness of the thermal grease is reduced, improving the adhesion between the metal plate 9a and the heat sink, and enhancing heat dissipation.

[0030] Furthermore, in Embodiment 1, a heat sink is provided attached to the side of the substrate 9 opposite to the side on which the semiconductor element 7 is mounted, and the case 1 and the heat sink are fixed together with screws. When the semiconductor device 100 is attached to the heat sink, that is, when it is tightened and fixed with screws through the holes 11, stress is generated in the case 1 as it is pulled toward the screw holes, raising concerns that the adhesive 15 may peel off. However, in Embodiment 1, by providing a protrusion 3 on the outer circumference 18 of the lid member 2, the outer circumference 18 is less prone to deformation, and the inner circumference 19 is more prone to deformation. Therefore, when stress is generated in the lid member 2 due to the deformation of the case 1, the more easily deformable inner circumference 19 deforms in accordance with the deformation of the case 1, thereby reducing the stress on the outer circumference 18 which is bonded to the case 1 via the adhesive 15. Thus, the strain generated in the adhesive 15 can be reduced, and the adhesive 15 can be made less prone to peeling off.

[0031] Furthermore, in Embodiment 1, the semiconductor element 7 is formed from a wide-bandgap semiconductor. This configuration reduces power loss in the semiconductor element 7 and enables high-temperature operation of the semiconductor element 7. As the wide-bandgap semiconductor, silicon carbide, gallium nitride-based materials, or diamond can be used.

[0032] In Embodiment 1, a stepped shape is provided on the inner circumference of the upper side wall of the case 1, and this stepped shape forms the edge portion 16. However, it is not necessary to provide a stepped shape. In this case, the outer circumference portion 18 of the lid member 2 will be placed on the upper surface of the side wall of the case 1, so the upper surface of the side wall of the case 1 will correspond to the edge portion 16 of the case 1.

[0033] In the first embodiment, the protrusion 3 of the lid member 2 is formed to continuously wrap around the outer circumference of the lid member 2, but it is also possible to have a configuration in which the protrusion 3 is formed only on a part of the outer circumference 18 of the lid member 2.

[0034] In the first embodiment, the inclined portion 4 of the protrusion 3 of the lid member 2 is formed to continuously wrap around the protrusion 3, but it is also possible to have a configuration in which the inclined portion 4 is formed only on a part of the protrusion 3.

[0035] Embodiment 2. The configuration of the semiconductor device 200 in Embodiment 2 will be described. Components that are the same as or equivalent to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted. Figure 4 is a cross-sectional view of Embodiment 2 along the cross-sectional line A-A in Figure 1. The semiconductor device 200 of Embodiment 2 differs from Embodiment 1 in that the protrusion 203 of the lid member 202 does not have an inclined portion 4, and the cross-section of the protrusion 203 in the XZ plane is rectangular.

[0036] As described above, in the semiconductor device 200 of Embodiment 2, the presence of a protrusion 203 on the outer peripheral portion 18 of the lid member 202 makes the maximum thickness of the outer peripheral portion 18 in the Z-axis direction greater than the maximum thickness of the inner peripheral portion 19 in the Z-axis direction. As a result, the inner peripheral portion 19 is more easily deformed than the outer peripheral portion 18, which is bonded to the case 1 via the adhesive 15. In other words, when the lid member 202 deforms, the more easily deformable inner peripheral portion 19 deforms, thereby mitigating the concentration of stress on the outer peripheral portion 18, which is bonded to the case 1. By mitigating the stress concentration on the outer peripheral portion 18, the strain generated in the adhesive 15 can be reduced. With this configuration, the adhesive 15 bonding the case 1 and the lid member 202 is less likely to peel off even when temperature changes occur.

[0037] Embodiment 3. The configuration of the semiconductor device 300 in Embodiment 3 will be described. Components that are the same as or equivalent to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted. Figure 5 is a cross-sectional view of Embodiment 3 along the cross-sectional line A-A in Figure 1. The semiconductor device 300 of Embodiment 3 differs from Embodiment 1 in that the outer peripheral portion 18 of the lid member 302 has a lid member side projection 21 in the portion facing the edge portion 16 of the case 1.

[0038] The lid member side projection 21 protrudes in the -Z direction, that is, toward the inside of the storage space 17 from the opening 12. When the outer peripheral portion 18 of the lid member 302 is positioned so as to rest on the edge portion 16 of the case 1, the lid member side projection 21 contacts the edge portion 16 of the case 1 via the adhesive 15. The lid member side projection 21 is formed to continuously wrap around the outer peripheral portion of the lid member 302.

[0039] As described above, in the semiconductor device 300 of Embodiment 3, the outer peripheral portion 18 of the lid member 302 has a lid member-side projection 21 that protrudes from the opening 12 toward the inside of the housing space 17 and contacts the edge portion 16 via the adhesive 15, in the portion facing the edge portion 16, thereby increasing the contact area between the lid member 302 and the adhesive 15. Furthermore, the lid member-side projection 21 acts as a spacer, creating a gap between the outer peripheral portion 18 and the edge portion 16 in the Z-axis direction, making it easier for the adhesive 15 to enter between the outer peripheral portion 18 and the edge portion 16. When the adhesive 15 enters between the outer peripheral portion 18 and the edge portion 16, the bonding area between the outer peripheral portion 18 and the edge portion 16 increases. With this configuration, the adhesive 15 can be made less likely to peel off. In addition, as the lid member-side projection 21 is covered by the adhesive 15, the lid member-side projection 21 becomes embedded inside the adhesive 15. As a result, the protruding portion 21 on the lid side functions as an anchor, allowing the outer circumference 18 and the edge portion 16 to be bonded more firmly.

[0040] In Embodiment 3, the lid member side projection 21 is formed to continuously wrap around the outer circumference of the lid member 302, but it is also possible to have a configuration in which the lid member side projection 21 is formed only on a part of the outer circumference 18 of the lid member 302.

[0041] Embodiment 4. The configuration of the semiconductor device 400 in Embodiment 4 will be described. The same or corresponding configurations as those in Embodiment 1 are denoted by the same reference numerals and their description will be omitted. FIG. 6 is a cross-sectional view taken along the cross-sectional line A-A of FIG. 1 in Embodiment 4. The semiconductor device 400 of Embodiment 4 is different from that of Embodiment 1 in that it has a case-side protruding portion 22 at the edge 16 of the case 401.

[0042] The case-side protruding portion 22 protrudes from the edge 16 of the case 401 in the +Z direction, that is, in the direction from the opening 12 toward the outside of the accommodation space 17. When the outer peripheral portion 18 of the lid member 2 is disposed so as to rest on the edge 16 of the case 401, the case-side protruding portion 22 contacts the outer peripheral portion 18 of the lid member 2 via the adhesive 15. The case-side protruding portion 22 is formed so as to continuously go around once along the edge 16 of the case 401.

[0043] As described above, in the semiconductor device 400 in Embodiment 4, by having the case-side protruding portion 22 that protrudes from the edge 16 of the case 40 to the outside of the accommodation space 17 in the direction from the opening 12 and contacts the outer peripheral portion 18 via the adhesive , the contact area between the case 401 and the adhesive 15 increases. Further, the case-side protruding portion 22 serves as a spacer, and by creating a gap between the outer peripheral portion 18 and the edge 16 in the Z-axis direction, the adhesive 15 easily enters between the outer peripheral portion 18 and the edge 16. When the adhesive 15 enters between the outer peripheral portion and the edge 16, the adhesive area between the outer peripheral portion 18 and the edge 16 increases. With such a configuration, the adhesive 15 can be made more difficult to peel off.

[0044] In Embodiment 4, the case-side protruding portion is formed so as to continuously go around once along the edge 16 of the case 401, but a configuration in which the case-side protruding portion 22 is formed only on a part of the edge 16 may also be employed.

[0045] Embodiment 5 The configuration of the semiconductor device 500 in Embodiment 5 will be described. The same or corresponding configurations as those in Embodiment 4 are denoted by the same reference numerals and their description will be omitted. FIG. 7 is a cross-sectional view taken along the sectional line A - A of FIG. 1 in Embodiment 5. The semiconductor device 500 in Embodiment 5 is different from that in Embodiment 4 in that the lid member 502 has the positioning protrusion 23.

[0046] The positioning protrusion 23 protrudes in the -Z direction, that is, in the direction from the opening 12 toward the inside of the accommodation space 17. Further, the positioning protrusion 23 is located on the inner peripheral side of the edge portion 16 of the case 401 and is formed so as to extend along the side surface on the inner peripheral side of the case 401. The positioning protrusion 23 is formed so as to continuously go around once along the edge portion 16 of the case 401. In the cross-section in the XZ plane, the surface of the positioning protrusion 23 facing the side surface on the inner peripheral side of the case 401 has an inclined surface that inclines away from the side surface on the inner peripheral side of the case 401 as it goes in the -Z direction.

[0047] As described above, in the semiconductor device 500 in Embodiment 5, the lid member 502 has the positioning protrusion 23 formed so as to protrude in the direction from the opening 12 toward the inside of the accommodation space 17 and extend along the side surface on the inner peripheral side of the case 401. Thus, when the lid member 502 is attached to the case 401, the positioning protrusion 23 serves as a positioning guide. Thereby, when the lid member 502 is attached to the case​​​

[0049] In Embodiment 5, the positioning projection 23 is formed on the lid member 502 so as to continuously wrap around the edge 16 of the case 401, but it is also possible to have a configuration in which the positioning projection 23 is formed on only a part of the lid member 502.

[0050] In Embodiment 5, an inclined surface was formed on the surface of the positioning projection 23 facing the inner circumferential side surface of the case 401, such that it moves away from the inner circumferential side surface of the case 401 as it moves in the -Z direction. However, such an inclined surface is not required to be formed on the positioning projection 23. For example, in a cross-section in the XZ plane, the surface of the positioning projection 23 facing the inner circumferential side surface of the case 401 may be formed to be parallel to the inner circumferential side surface of the case 401.

[0051] In Embodiment 5, a case-side protrusion 22 is provided, but instead of the case-side protrusion 22, the lid member-side protrusion 21 described in Embodiment 3 may be provided.

[0052] Embodiment 6 The configuration of the semiconductor device 600 in Embodiment 6 will be described. Components that are the same as or equivalent to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted. Figure 8 is a cross-sectional view of Embodiment 6 along the cross-sectional line A-A in Figure 1. The semiconductor device 600 of Embodiment 6 differs from that of Embodiment 1 in that the lid member 602 has recesses 24a and 24b.

[0053] The lid member 602 has a recess 24a on the +Z direction side of the inner circumference 19, that is, the side furthest from the semiconductor element 7, and a recess 24b on the -Z direction side of the inner circumference 19, that is, the side closer to the semiconductor element 7. The recesses 24a and 24b are each formed to extend in the Y-axis direction. The recesses 24a and 24b are formed alternately in the X-axis direction over the entire area of ​​the inner circumference 19.

[0054] As described above, in the semiconductor device 600 of Embodiment 6, the lid member 602 has recesses 24a and 24b on the surface of the inner circumference 19 that is farther from the semiconductor element 7 and on the surface of the inner circumference 19 that is closer to the semiconductor element 7, making the inner circumference 19 more easily deformable. By making the inner circumference 19 more easily deformable, the concentration of stress on the outer circumference 18 that is bonded to the case 1 can be further reduced. By reducing the concentration of stress on the outer circumference 18, the strain generated in the adhesive 15 can be further reduced, and the adhesive 15 that bonds the case 1 and the lid member 602 can be made less likely to peel off.

[0055] In Embodiment 6, a recess 24a was formed on the +Z-direction side of the inner circumference 19, and a recess 24b was formed on the -Z-direction side of the inner circumference 19. However, the recess 24a may be formed on the +Z-direction side of the inner circumference 19, and the -Z-direction side may be left flat without a recess 24b. Alternatively, the +Z-direction side of the inner circumference 19 may be left flat without a recess 24a, and the -Z-direction side may be formed with a recess 24b. These configurations also make it more difficult for the adhesive 15 bonding the case 1 and the lid member 602 to peel off. In other words, if a recess 24a or a recess 24b is formed on at least one of the sides of the inner circumference 19 that is farther from the semiconductor element 7 and the sides of the inner circumference 19 that is closer to the semiconductor element 7, the adhesive 15 bonding the case 1 and the lid member 602 to peel off can be made more difficult for the adhesive 15 to peel off.

[0056] In Embodiment 6, the recesses 24a and 24b were formed to extend in the Y-axis direction, but the recesses 24a and 24b may be formed to extend in any direction within the XY plane. Furthermore, the recesses 24a and 24b are not limited to shapes that extend linearly within the XY plane. Also, in Embodiment 6, the recesses 24a and 24b were formed alternately in the X-axis direction, but this is not limited. The recesses 24a and 24b may be formed alternately in directions other than the X-axis direction within the XY plane. The recesses 24a and 24b may not be formed alternately, but rather multiple recesses 24a or multiple recesses 24b may be formed consecutively. Also, in Embodiment 6, the recesses 24a and 24b were formed over the entire area of ​​the inner circumference 19, but the recesses 24a and 24b may be formed only in a part of the inner circumference 19. The individual sizes of the multiple recesses 24a and multiple recesses 24b are arbitrary. The number of recesses 24a and 24b formed is also arbitrary. If at least one of either recesses 24a or recess 24b is formed, it can be expected that the adhesive 15 that bonds the case 1 and the lid member 602 will be less likely to peel off.

[0057] 1, 401 Case 2, 202, 302, 502, 602 Lid member 3, 203 Protrusion 4 Inclined part 5 Terminal 6 Internal wiring 7 Semiconductor element 8 Bonding material 9 Substrate 9a Metal plate 9b Insulating layer 9c Conductive pattern 10 Sealing material 11 Hole 12 Opening 13 Opening for substrate 14 Adhesive 15 Adhesive 16 Edge 17 Housing space 18 Outer periphery 19 Inner periphery 20 Outermost periphery 21 Protrusion on lid member side 22 Protrusion on case side 23 Positioning protrusion 24a Recess 24b Recess 100, 200, 300, 400, 500, 600 Semiconductor device

Claims

1. A semiconductor device comprising: a semiconductor element; a case having a housing space for housing the semiconductor element and an edge portion forming an opening in the housing space; a lid member having an outer peripheral portion that covers the opening and has a protrusion projecting from the opening toward the outside of the housing space, and an inner peripheral portion located on the inner side of the outer peripheral portion; and an adhesive for bonding the edge portion and the outer peripheral portion.

2. The semiconductor device according to claim 1, wherein the protrusion has an inclined portion on the outer circumference of the protrusion such that the cross-sectional area of ​​the protrusion on a plane parallel to the opening decreases as it moves away from the opening.

3. The semiconductor device according to claim 2, wherein the protrusion is formed to continuously wrap around the outer circumference of the lid member, and the inclined portion is formed to continuously wrap around the protrusion.

4. The semiconductor device according to any one of claims 1 to 3, wherein the outer peripheral portion has a lid member side projection that protrudes in a direction toward the inside of the housing space from the opening and contacts the edge portion via the adhesive, in the portion facing the edge portion.

5. The semiconductor device according to any one of claims 1 to 3, wherein the case has a case-side projection on its edge that protrudes from the opening toward the outside of the housing space and contacts the outer periphery via the adhesive.

6. The semiconductor device according to any one of claims 1 to 5, wherein the lid member has a positioning projection that protrudes from the opening toward the inside of the housing space and is formed to extend along the inner circumferential side surface of the case.

7. The semiconductor device according to claim 6, wherein the positioning projection is formed to continuously wrap around the edge.

8. The inclined portion is formed to extend to the outermost part of the outer circumference, and the thickness of the outermost part of the outer circumference is thinner than the thickness of the inner circumference, according to claim 2 or claim 3.

9. The semiconductor device according to any one of claims 1 to 8, wherein the lid member has a recess on at least one of the surfaces of the inner circumference that are far from the semiconductor element and the surfaces of the inner circumference that are close to the semiconductor element.

10. The semiconductor device according to any one of claims 1 to 9, further comprising a substrate on which the semiconductor element is mounted, wherein the case has a substrate opening at a position opposite to the opening, the surface of the substrate on which the semiconductor element is mounted is located inside the case, and the surface of the substrate opposite to the surface on which the semiconductor element is mounted extends outside the case through the substrate opening.

11. The semiconductor device according to claim 10, further comprising a heat dissipation member attached to the side of the substrate opposite to the side on which the semiconductor element is mounted, wherein the case and the heat dissipation member are fixed by screws.

12. The semiconductor device according to any one of claims 1 to 11, wherein the semiconductor element is formed of a wide-bandgap semiconductor.

13. The semiconductor device according to claim 12, wherein the wide-bandgap semiconductor is one of silicon carbide, gallium nitride, gallium oxide, or diamond.

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