Semiconductor device, electric equipment and method for manufacturing semiconductor device

Abstract

To provide a semiconductor device which can suppress peeling between a joint material and a resin sealing body, while securing joining to a substrate of a semiconductor element, has high reliability, and is versatile, electric equipment and a method for manufacturing a semiconductor device.SOLUTION: A semiconductor device includes a substrate, a semiconductor element joined to the substrate by a joint material, and a resin sealing body for resin-sealing the substrate and the semiconductor element, wherein the substrate has a recess surrounding the semiconductor element, on a joint surface to the semiconductor element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor device, an electric device, and a method for manufacturing a semiconductor device. [Background technology]

[0002] A typical semiconductor device is manufactured by electrically connecting a semiconductor element (including a power chip or a control chip) to a substrate (including a circuit board on which a metal pattern is formed or a lead frame with inner leads) by bonding it with a bonding material (including solder or a conductive adhesive), and then resin-sealing the substrate and semiconductor element with a resin sealant such as mold resin.

[0003] In particular, power chips such as transistors and diodes, which are typical semiconductor elements that handle large amounts of power, are mainly joined to metal patterns by soldering in the reflow process. Control chips such as control ICs, which do not handle as much power as power chips, are sometimes connected with conductive adhesive instead of soldering.

[0004] For example, when soldering power chips, because power chips handle large amounts of power and therefore suffer significant heat loss, it is important to dissipate heat through the metal pattern to prevent thermal breakdown. Therefore, solder is typically applied thickly to prevent a reduction in the contact area between the power chip and the metal pattern, and to prevent poor adhesion between the power chip and the metal pattern due to an insufficient amount of solder. In this case, too much solder can cause the solder to overflow beyond the designated area. However, this can lead to poor adhesion between the solder and the molded resin, and if the overflow amount increases, gaps can form between the solder and the molded resin, allowing moisture and other substances to penetrate and degrading the performance of the semiconductor device. Therefore, efforts are being made to prevent the solder from overflowing beyond the designated area in order to minimize gaps between the solder and the molded resin and improve adhesion.

[0005] Patent Document 1 discloses a semiconductor device having a key groove and a non-wetting portion on a substrate (die pad portion of a lead frame) on which a semiconductor element is mounted. This will be described with reference to FIG.

[0006] The idea is to first surround the four corners of the semiconductor element with four L-shaped key grooves, allowing solder to flow into the grooves and preventing the solder from leaking outward. An example has been disclosed in which four inner L-shaped key grooves (first key groove 2) and four more outer L-shaped key grooves (second key groove 3) are provided to accommodate semiconductor elements of different sizes. A small semiconductor element is then placed in a first bonding area 4 (inside the dashed line in Figure 7) within the first key groove 2, and a large semiconductor element is placed in a second bonding area 5 within the second key groove 3.

[0007] Next, non-wetted portions 6 are formed on the portions (four sides) linearly connecting the outer second key grooves 3, and the semiconductor element is surrounded by the second key grooves 3 and the non-wetted portions 6. The non-wetted portions 6 are treated to make them less susceptible to solder wetting, and it is disclosed that the surface of the substrate 1 is oxidized using a laser or the like, for example. It is also stated that because the non-wetted portions 6 are less susceptible to solder wetting, it is possible to prevent the solder in the second bonding region 5 from spreading outside the second bonding region 5. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-12567 Summary of the Invention [Problem to be solved by the invention]

[0009] The applications of semiconductor devices are expanding year by year, and they are now handling ever-increasing amounts of power. The materials used for semiconductor elements are also expanding from silicon (Si) to compound semiconductors, such as silicon carbide (SiC) and gallium nitride (GaN). This has led to a noticeable problem of peeling of molding resins that come into contact with solder.

[0010] Specifically, in reliability tests for semiconductor devices, test conditions are made stricter to match the actual usage environment, but the greater the power handled, the greater the amount of heat generated and the higher the usage temperature tends to be. For example, even in the TCT (Thermal Cycle Test), the temperature under the high-temperature condition is made higher, and as a result, the temperature difference between the low-temperature and high-temperature conditions increases, and it is thought that peeling is more likely to occur due to the difference in the thermal expansion coefficients of the solder and mold resin.

[0011] To begin with, the adhesion between the solder and the molded resin is poor, and as the high-temperature conditions become more severe due to increased power, peeling of the molded resin in contact with the solder becomes more likely to occur, so some kind of measure to prevent peeling is becoming necessary.

[0012] Here, it is an effective idea to prevent the solder from spreading beyond a predetermined area, as in the conventional technique disclosed in Patent Document 1.

[0013] However, it was necessary to form the key groove and non-wetting portion on the substrate before bonding the semiconductor element, and there was a problem that it was difficult to adjust later to accommodate changes in the semiconductor element used (for example, if the power became higher or the size changed), resulting in a lack of versatility.

[0014] This will be explained with reference to Figures 8 and 9. Figure 8 shows the case of a large semiconductor element 7, and although the solder 8 overflows to the outside of the large semiconductor element 7, the overflowing solder is blocked by the non-wetted portion 6 and flows into the second key groove 3, so the area of ​​the excess solder (the portion visible in Figure 8) is kept small to a certain extent.

[0015] Figure 9 shows the case of a small semiconductor element 9, in which solder 10 protrudes outside the small semiconductor element 9, and the protruding solder that flows toward the corners of the small semiconductor element 9 flows into the first key groove 2, while the solder that flows toward the sides of the small semiconductor element 9 continues to flow for a while and is blocked only when it reaches the non-wetted portion 6. Therefore, the area of ​​the excess solder (the portion visible in Figure 9) is significantly larger than in the case of the large semiconductor element 7 in Figure 8. Therefore, when a small semiconductor element 9 is used, the area of ​​contact between the solder 10 and the molded resin (not shown) also becomes larger, making the molded resin more likely to peel off.

[0016] This is because, in order to accommodate both the semiconductor element (large) 7 and the semiconductor element (small) 9, the distance between the first key groove 2 and the second key groove 3 must be increased, which results in a greater distance from the semiconductor element (small) 9 to the non-wetted portion 6.

[0017] As an alternative, it is conceivable to form a separate non-wetting portion for the small semiconductor element 9, for example, on the linear portion (four sides) connecting the key grooves of the first key groove 2. However, if the large semiconductor element 7 is used in this configuration, the large semiconductor element 7 will cover this separate non-wetting portion, and solder will not adhere to this separate non-wetting portion, resulting in a gap between the large semiconductor element 7 and the substrate 1, reducing the contact area and preventing proper bonding. Therefore, it is not possible to achieve both the small semiconductor element 9 and the large semiconductor element 7.

[0018] Further explanation will be given below. Fig. 10 is a cross-sectional view of a typical semiconductor device after it has been sealed with resin.

[0019] The semiconductor device 11 includes a substrate 12, a power chip (semiconductor element) 13 and a control chip (semiconductor element) 14 arranged on the upper surface of the substrate 12, a lead frame having a power lead 15 and a signal lead 16, and a resin sealant 17 that seals the power chip (semiconductor element) 13 and the control chip (semiconductor element) 14 on the substrate 12 and the lead frame with resin, and the tip of the power lead 15 is joined to the upper surface of the substrate 12 by a bonding material 18 (solder, conductive adhesive, etc.), and the substrate 12 is provided with a metal pattern layer 19.

[0020] In addition, the power supply lead 15 has a bonding pad 20 and a die pad 21, the lower surface of the die pad 21 is bonded to the upper surface of the substrate 12 by a bonding material 18, the power chip (semiconductor element) 13 is placed on the upper surface of the die pad 21 and bonded by the bonding material 18, and the power chip (semiconductor element) 13 and the bonding pad 20 are connected by a wire 22.

[0021] The signal lead 16 is connected to the metal pattern layer 19 by a wire 23 .

[0022] In such a general configuration, power chip (semiconductor element) 13 and control chip (semiconductor element) 14 are bonded to metal pattern layer 19 formed on substrate 12 and die pad 21 of a lead frame equipped with inner leads by bonding material 18, but when attempting to ensure bonding of the semiconductor element to the substrate, bonding material 18 protrudes as described above, and becomes larger than power chip (semiconductor element) 13 and control chip (semiconductor element) 14. And as described above, when the contact area between bonding material 18 and resin encapsulant 17 becomes large, peeling becomes more likely to occur.

[0023] The present disclosure has been made to solve the above problems, and aims to provide a highly reliable, general-purpose semiconductor device, electrical equipment, and method for manufacturing a semiconductor device that can suppress peeling between the bonding material and the resin sealing body while ensuring bonding of the semiconductor element to the substrate. [Means for solving the problem]

[0024] The present disclosure has been made to solve the above-mentioned problems, and provides a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that resin-seals the substrate and the semiconductor element, wherein the substrate has a recess that surrounds the semiconductor element on the bonding surface with the semiconductor element.

[0025] In such a semiconductor device, the bonding surface of the substrate with the semiconductor element has a recess surrounding the semiconductor element, and the bonding of the semiconductor element to the substrate is ensured by the bonding material inside the recess, while the bonding material that has spread away from the periphery of the semiconductor element due to the recess is removed, thereby reducing the area of ​​the protruding bonding material and, as a result, reducing the area of ​​the bonding material in contact with the resin encapsulant, thereby preventing peeling between the bonding material and the resin encapsulant, resulting in a highly reliable, general-purpose semiconductor device.

[0026] It is also preferable that the position of the wall of the recess on the side closer to the semiconductor element and the position of the outer edge of the bonding material coincide at least partially.

[0027] As a result, the bonding material is located inside the recessed portion, so the area of ​​the bonding material that protrudes from this portion is small, making it possible to prevent the bonding material from peeling off from the resin sealing body.

[0028] The bottom surface of the recess preferably has a roughened structure.

[0029] If the bottom surface of the recess has a roughened structure, the adhesion to the resin encapsulant is enhanced due to the anchor effect compared to a flat structure, and peeling of the resin encapsulant can be further suppressed.

[0030] The semiconductor element is preferably an element made of a compound semiconductor.

[0031] This makes it possible to effectively prevent peeling between the bonding material and the resin sealing body, which is a significant problem in the case of elements made of compound semiconductors.

[0032] The present disclosure can also provide an electrical device including the semiconductor device.

[0033] This allows for the use of a highly reliable, general-purpose semiconductor device that can ensure bonding of the semiconductor element to the substrate while suppressing peeling between the bonding material and the resin encapsulant, resulting in an electrical device with excellent durability.

[0034] The present disclosure has also been made to solve the above-mentioned problems, and provides a method for manufacturing a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin encapsulant that resin-encapsulates the substrate and the semiconductor element, the method comprising: a bonding step of bonding the semiconductor element to the substrate with the bonding material; a recess formation step of removing the bonding material that has overflowed around the semiconductor element in the bonding step and a portion of the surface of the substrate, to form a recess that closely surrounds the periphery of the semiconductor element; and a resin encapsulation step of resin-encapsulating the substrate and the semiconductor element.

[0035] This method of manufacturing a semiconductor device can remove the bonding material that has protruded beyond the periphery of the semiconductor element and a portion of the surface of the substrate, thereby forming a recess that closely surrounds the periphery of the semiconductor element. Therefore, while the bonding material ensures bonding of the semiconductor element to the substrate within the recess, removing the bonding material that has protruded beyond the periphery of the semiconductor element when forming the recess reduces the area of ​​exposed bonding material, thereby reducing the area of ​​bonding material that contacts the resin encapsulant, thereby preventing peeling between the bonding material and the resin encapsulant. This allows for the manufacture of a highly reliable, general-purpose semiconductor device.

[0036] In particular, if the bonding material that has protruded around the semiconductor element is removed together with part of the surface of the substrate, the bonding material will not remain on the surface of the substrate, and the bonding material can be removed more reliably.

[0037] Preferably, the recess forming step includes removing the bonding material that has protruded around the semiconductor element and a part of the surface of the substrate by irradiating a laser.

[0038] This allows the bonding material that has protruded around the semiconductor element to be removed with precision and accuracy using a laser.

[0039] It is also preferable that the bottom surface of the recess has a roughened structure.

[0040] In this way, the recess is first formed by removing the bonding material and a portion of the surface of the substrate, and since there is no bonding material in the recess, adhesion to the resin sealing body is improved.Furthermore, if the bottom surface of the recess is made roughened, adhesion to the resin sealing body is improved due to the anchor effect compared to a flat structure, so peeling of the resin sealing body can be further suppressed.

[0041] It is also preferable that the semiconductor element is an element made of a compound semiconductor.

[0042] This makes it possible to effectively prevent peeling between the bonding material and the resin sealing body, which is a significant problem in the case of elements made of compound semiconductors. [Effects of the Invention]

[0043] As described above, the semiconductor device of the present disclosure has a recess surrounding the semiconductor element on the bonding surface of the substrate where the semiconductor element is bonded, and therefore the bonding material ensures bonding of the semiconductor element to the substrate within the recess, while the recess allows the bonding material that has spread away from the periphery of the semiconductor element to be removed, thereby reducing the area of ​​the protruding bonding material and, as a result, reducing the area of ​​the bonding material in contact with the resin encapsulant, thereby preventing peeling between the bonding material and the resin encapsulant, resulting in a highly reliable, general-purpose semiconductor device.

[0044] Furthermore, the method for manufacturing a semiconductor device according to the present disclosure can remove the bonding material that has protruded beyond the periphery of the semiconductor element and a portion of the surface of the substrate to form a recess that closely surrounds the periphery of the semiconductor element, thereby ensuring bonding of the semiconductor element to the substrate within the recess, and by removing the bonding material that has protruded beyond the periphery of the semiconductor element when forming the recess, the area of ​​the exposed bonding material is reduced, and as a result, the area of ​​the bonding material that contacts the resin encapsulant is reduced, thereby preventing peeling between the bonding material and the resin encapsulant. This allows for the manufacture of a highly reliable, general-purpose semiconductor device.

[0045] In particular, if the bonding material that has protruded around the semiconductor element is removed together with part of the surface of the substrate, the bonding material will not remain on the surface of the substrate, and the bonding material can be removed more reliably.

[0046] Furthermore, an electrical device equipped with the semiconductor device of the present disclosure can be an electrical device with excellent durability by using a highly reliable, general-purpose semiconductor device that can ensure bonding of the semiconductor element to the substrate while suppressing peeling between the bonding material and the resin sealing body. [Brief explanation of the drawings]

[0047] [Figure 1] FIG. 2 is a cross-sectional view of the semiconductor device after being sealed with resin according to the embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram of a semiconductor device according to an embodiment of the present disclosure after chip mounting. [Figure 3] FIG. 2 is a schematic diagram of a semiconductor device after laser processing in an embodiment of the present disclosure. [Figure 4] 5A to 5C are schematic diagrams illustrating a recess forming step of forming recesses in a substrate according to an embodiment of the present disclosure. [Figure 5] FIG. 4 is a schematic diagram of a laser trajectory used in a recess formation step according to an embodiment of the present disclosure. [Figure 6] 1 is a diagram illustrating an air conditioner as an embodiment of an electrical appliance including a semiconductor device according to the present disclosure. [Figure 7] 1 is a schematic diagram of a conventional semiconductor device in which a key groove portion and a non-wetting portion are formed on a substrate. [Figure 8] FIG. 1 is a schematic diagram showing a conventional semiconductor device to which a large semiconductor element is bonded. [Figure 9] FIG. 1 is a schematic diagram showing a case where a semiconductor element (small) is bonded to a conventional semiconductor device. [Figure 10] FIG. 1 is a cross-sectional view of a typical semiconductor device after being sealed with resin. DETAILED DESCRIPTION OF THE INVENTION

[0048] The present disclosure will be described in detail below, but the present disclosure is not limited thereto.

[0049] As described above, there has been a need to provide a highly reliable, general-purpose semiconductor device, electrical device, and method for manufacturing a semiconductor device that can suppress peeling between the bonding material and the resin sealing body while ensuring bonding of the semiconductor element to the substrate.

[0050] As a result of extensive research into the above-mentioned problems, the inventors discovered that by forming a recess surrounding the semiconductor element on the bonding surface of the substrate where the semiconductor element is bonded, the area of ​​exposed bonding material can be minimized, thereby ensuring bonding of the semiconductor element to the substrate while suppressing peeling between the bonding material and the resin sealing body, and thus completed the present disclosure.

[0051] At this time, the inventors carried out confirmation experiments using Si chips, SiC chips, and GaN chips as semiconductor elements under the same conditions of TCT (-50 to 175°C), and were able to confirm sufficient effects in all cases.

[0052] That is, the present disclosure relates to a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that resin-seals the substrate and the semiconductor element, wherein the substrate has a recess that surrounds the semiconductor element on the bonding surface with the semiconductor element.

[0053] The present disclosure also relates to an electrical device including the semiconductor device.

[0054] Furthermore, the present disclosure provides a method for manufacturing a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin encapsulant that resin-encapsulates the substrate and the semiconductor element, the method comprising: a bonding step of bonding the semiconductor element to the substrate with the bonding material; a recess formation step of removing the bonding material that has overflowed around the semiconductor element in the bonding step and a portion of the surface of the substrate, thereby forming a recess that closely surrounds the periphery of the semiconductor element; and a resin encapsulation step of resin-encapsulating the substrate and the semiconductor element.

[0055] The following description will be made with reference to the drawings.

[0056] FIG. 1 shows an example of a semiconductor device according to the present disclosure. As shown in FIG. 1, the semiconductor device 41 according to the present disclosure includes a substrate 31, a semiconductor element 33 bonded to the substrate 31 with a bonding material 32, and a resin encapsulant 40 that resin-encapsulates the substrate 31 and the semiconductor element 33. The substrate 31 has a recess 34 surrounding the semiconductor element 33 on the bonding surface with the semiconductor element 33. The recess 34 surrounding the semiconductor element 33 is formed by removing a portion of the surface of the substrate 31 around the semiconductor element 33 after bonding the semiconductor element 33 to the substrate 31 with the bonding material 32, as described below. Therefore, no bonding material 32 is present in the recess 34. This minimizes the exposed area of ​​the bonding material 32 that protrudes from the periphery of the semiconductor element 33 while ensuring the bonding strength between the semiconductor element 33 and the substrate 31. This reduces the area of ​​the bonding material 32 that contacts the resin encapsulant 40, thereby preventing peeling between the bonding material 32 and the resin encapsulant 40.

[0057] The wall 34a of the recess on the side closest to the semiconductor element and the outer edge 38 of the bonding material 32 can be positioned at least partially in line with each other. As will be described later, the bonding material is also removed when the recess is formed. However, if there are areas where the bonding material does not protrude much, the wall 34a of the recess on the side closest to the semiconductor element and the outer edge 38 of the bonding material 32 may not necessarily be positioned in line with each other. However, when reliably bonding the semiconductor element to the substrate, a sufficient amount of bonding material is used, which results in a large amount of bonding material protruding. Therefore, when the recess is formed, the bonding material is removed from the entire area where the recess is to be formed. Therefore, it is preferable that the wall 34a of the recess on the side closest to the semiconductor element and the outer edge 38 of the bonding material 32 be positioned in line with each other over the entire wall of the recess on the side closest to the semiconductor element.

[0058] Although not particularly limited, the width of the recess 34 can be, for example, 0.5 mm, and the depth of the recess 34 can be, for example, about 7 μm. These can be adjusted by appropriately setting conditions in the recess formation step described below.

[0059] Furthermore, although not particularly limited, it is preferable that the bottom surface 34c of the recess 34 has a roughened structure. In this case, the roughened structure of the bottom surface 34c is not at least a glossy surface, and the roughness can be adjusted, for example, by setting processing conditions.

[0060] If the bottom surface 34c of the recess 34 has a roughened structure, the adhesion to the resin sealing body is increased due to the anchor effect compared to a flat structure, and peeling of the resin sealing body can be further suppressed.

[0061] Furthermore, although not particularly limited, the substrate can be a circuit board on which a metal pattern is formed or a lead frame with inner leads.

[0062] The lead frame including the inner lead is not particularly limited, but can be made of a copper alloy plate material.

[0063] The substrate is not particularly limited as long as it can accommodate semiconductor elements. The substrate can be an insulating metal substrate having a metal pattern on its upper surface, an insulating layer, and a heat dissipation layer on its lower surface. The materials for each are not particularly limited. The metal pattern may be copper foil, and the heat dissipation layer may be an aluminum plate, or the heat dissipation layer may be a copper plate. The insulating layer is not particularly limited, but can be polyimide resin.

[0064] The substrate may also be an insulating circuit board, which is a ceramic substrate with metal patterns on both sides, such as a DBC (Direct Bonded Copper Substrate) substrate, in which copper is directly bonded to an insulating ceramic substrate, or an AMB (Active Metal Brazing Substrate) substrate.

[0065] Although not particularly limited, the bonding material 32 can be solder or a conductive adhesive.

[0066] Although not particularly limited, the semiconductor element may be a power chip or a control chip.

[0067] The power chip is not particularly limited, but may be a power chip such as a transistor or diode that handles large amounts of power, and may be an IGBT (Insulated Gate Bipolar Transistor).

[0068] The control chip is not particularly limited, but may be a control chip such as a control IC that does not handle as much power as a power chip, and may be a monolithic IC (Monolithic Integrated Circuit).

[0069] However, power chips that handle larger amounts of power tend to have thicker solder applied to them so as not to weaken the adhesion between the power chip and the metal pattern or lead frame, so it is expected that a larger amount of solder will overflow. In other words, when the present disclosure is applied, peeling between the bonding material and the resin sealing body can be effectively suppressed, so it is preferable to use a power chip.

[0070] Furthermore, although not particularly limited, the semiconductor element may be an element made of a compound semiconductor. For example, the compound semiconductor may be SiC, GaN, or the like. In the case of an element made of a compound semiconductor, the problem of peeling between the bonding material and the resin encapsulant is significant, so this is preferable because it can effectively prevent peeling between the bonding material and the resin encapsulant.

[0071] Although not particularly limited, a specific example of the semiconductor device may be an intelligent power module (IPM). In the example of an IPM, multiple semiconductor devices may be provided on a DBC substrate or an AMB substrate.

[0072] The present disclosure can also be applied to cases where semiconductor components are used instead of the semiconductor element, such as chip resistors, capacitors, thermistors, and press-fit pin sleeves.

[0073] Hereinafter, a method for manufacturing a semiconductor device according to the present disclosure will be described.

[0074] 2A and 2B are schematic diagrams of a substrate after chip mounting of a semiconductor device according to an embodiment of the present disclosure, where FIG. 2A is a top view and FIG. 2B is a cross-sectional view taken along the line AA' in FIG. 2A.

[0075] Chip mounting refers to the bonding process of bonding a semiconductor element 33 onto a substrate 31 using a bonding material 32. When this chip mounting is completed, a sufficient amount of bonding material is used to ensure the bonding strength of the semiconductor element 33, so the bonding material 32 often overflows widely around the semiconductor element 33.

[0076] 3A and 3B are schematic diagrams of the substrate after the chip mounting and subsequent recess forming step, where FIG. 3A is a top view and FIG. 3B is a cross-sectional view taken along the line AA' in FIG. 3A.

[0077] In the recess forming step, the bonding material 32 that protrudes around the semiconductor element 33 and part of the surface of the substrate 31 are removed by, for example, laser processing, to form a recess 34 that closely surrounds the periphery of the semiconductor element 33.

[0078] The removal method is not limited to laser processing, but a removal method using laser irradiation is more preferable because it allows for accurate and reliable removal.

[0079] After the removal process, the bonding surface between the substrate 31 and the semiconductor element 33 has a recess 34 surrounding the semiconductor element 33. When the recess 34 is formed, most of the portion of the bonding material 32 that protrudes around the semiconductor element is also removed. Comparing Figures 2 and 3, it is clear that the protruding area of ​​the bonding material is smaller.

[0080] The recess forming step will be described in more detail below, taking an example in which the recess forming step is performed by laser irradiation. Figure 4 is a schematic diagram of the recess forming step in which recesses are formed in a substrate.

[0081] A laser beam 35 is irradiated onto the substrate 31 from above, and the position of the laser beam 35 is moved in the direction D to remove the protruding portion 36 of the bonding material 32 and a portion 37 of the upper surface of the substrate 31, thereby forming a recess 34. The recess 34 has a wall 34a on the side closer to the semiconductor element, a wall 34b on the side farther from the semiconductor element, and a bottom surface 34c. Although not particularly limited, the position of the upper end of the wall 34a on the side closer to the semiconductor element of the recess 34 coincides with the position of an outer edge 38 of the bonding material at least in part. This indicates that the protruding portion 36 of the bonding material 32 is removed as intended, depending on the irradiation position of the laser beam 35. As a result, at least a portion of the bonding material 32 is located inside the recess 34 (toward the semiconductor element). Therefore, in this portion, the width B of the bonding material that will ultimately protrude can be reduced as intended, and the area of ​​the protruding bonding material (the area in contact with the resin encapsulant) can be reduced, thereby suppressing peeling between the bonding material and the resin encapsulant.

[0082] Here, the laser 35 can be irradiated using a commercially available laser device, for example, MD-X2500(A) manufactured by Keyence Corp., although it is not particularly limited thereto. The diameter C of the laser irradiation is not particularly limited, but it can be set to, for example, 0.04 mm.

[0083] Furthermore, it is preferable that the width B of the bonding material that finally protrudes is as small as possible, and although there are no particular limitations, it can be set to 2 μm.

[0084] Figure 5 is a schematic diagram of the trajectory of the laser used in the recess formation process. Although not particularly limited, it is possible to program the laser to trace a trajectory like the arrow in Figure 5(a) and repeat this several times. However, when actually irradiating a semiconductor device 39 mounted with the laser, although not particularly limited, it is preferable to program the laser not to irradiate when moving over the semiconductor device 39, but to irradiate when moving over an area where there is no semiconductor device 39, as shown in Figure 5(b).

[0085] Although not particularly limited, in the case of a semiconductor element of 2.7 mm square, the total laser irradiation time can be 10 seconds or less, and may be 3 seconds or less.

[0086] 1, the semiconductor device of the present disclosure requires a resin encapsulant 40 for resin-encapsulating the substrate 31 and the semiconductor element 33, and the method for manufacturing the semiconductor device of the present disclosure requires a resin encapsulation step for resin-encapsulating the substrate and the semiconductor element in addition to the bonding step and the recess forming step. However, the resin encapsulant and the resin encapsulation step can use a conventional general configuration and method as described with reference to FIG. 10, and therefore a description thereof will be omitted here.

[0087] Although not particularly limited, a mold resin can be used as the resin sealant, and although not particularly limited, the mold resin can be an epoxy resin sealant.

[0088] [Electrical Equipment] Furthermore, an embodiment of an electrical device including the semiconductor device of the present disclosure will be described with reference to FIG.

[0089] The semiconductor device described above can be applied to electrical equipment. By using a highly reliable, general-purpose semiconductor device that can ensure bonding of a semiconductor element to a substrate while suppressing peeling between the bonding material and the resin encapsulant, electrical equipment with excellent durability can be obtained.

[0090] The electrical equipment is not particularly limited, but in particular, in the example of the semiconductor device (IPM) mentioned above, it can be suitably applied as a small high-voltage three-phase motor driver to electrical equipment for driving compressors such as air conditioners and refrigerators, or to the main motor of washing machines.

[0091] 6 is a diagram illustrating an air conditioner 300 as one embodiment of an electrical device. The air conditioner 300 comprises an indoor unit 310 and an outdoor unit 320, each of which is equipped with fan motors 311 and 321, a compressor 322, and an IPM 200 as a semiconductor device. It is preferable to use IPM 200 with specifications suitable for driving the respective motors and compressors.

[0092] The present specification includes the following aspects. [1]: A semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that seals the substrate and the semiconductor element with resin, The semiconductor device is characterized in that the substrate has a recess surrounding the semiconductor element on a surface to be bonded to the semiconductor element. [2]: The semiconductor device according to [1] above, characterized in that the position of the wall of the recess on the side closer to the semiconductor element and the position of the outer edge of the bonding material are at least partially aligned. [3]:

[0023] The bottom surface of the recessed portion according to [1] or [2] above, characterized in that the bottom surface of the recessed portion has a roughened structure. Semiconductor device. [4]: The semiconductor device according to any one of the above [1] to [3], wherein the semiconductor element is an element made of a compound semiconductor. [5]: An electrical device comprising the semiconductor device according to any one of [1] to [4] above. [6]: A method for manufacturing a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that seals the substrate and the semiconductor element with resin, a bonding step of bonding the semiconductor element to the substrate with the bonding material; a recess forming step of removing the bonding material that has protruded around the periphery of the semiconductor element in the bonding step and a part of the surface of the substrate to form a recess that closely surrounds the periphery of the semiconductor element; a resin sealing step of sealing the substrate and the semiconductor element with resin; 1. A method for manufacturing a semiconductor device, comprising: [7]: The method for manufacturing a semiconductor device described in [6] above, wherein the recess forming step is characterized by removing the bonding material that has protruded around the semiconductor element and a part of the surface of the substrate by irradiating a laser. [8]: The method for manufacturing a semiconductor device according to the above [6] or [7], wherein the bottom surface of the recess is roughened. [9]: The method for manufacturing a semiconductor device according to any one of the above [6] to [8], wherein the semiconductor element is an element made of a compound semiconductor.

[0093] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Explanation of symbols]

[0094] 1, 12, 31...substrate, 2...first key groove, 3...second key groove, 4...first bonding area, 5...second bonding area, 6...non-wetted portion, 7...semiconductor element (large), 8, 10...solder (bonding material), 9...semiconductor element (small), 11, 41...semiconductor device, 13...power chip (semiconductor element), 14...control chip (semiconductor element), 15...power lead, 16...signal lead, 17, 40...resin encapsulant, 18, 32...bonding material, 19...metal pattern layer, 20...bonding pad, 21...die pad, 22, 23...wire, 33, 39...semiconductor element, 34...recess, 34a...wall closer to semiconductor element, 34b...wall farther from semiconductor element, 34c...bottom, 35...laser, 36...protruding portion, 37...Part of the upper surface of the substrate, 38...Outer edge of the bonding material, 200...IPM (semiconductor device), 300...Air conditioner, 310...Indoor unit, 311, 321...Fan motor, 320...Outdoor unit, 322...Compressor. B...Width of the final protruding joining material, C...Diameter of laser irradiation, D...Direction.

Claims

1. A semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that seals the substrate and the semiconductor element with resin, The semiconductor device is characterized in that the substrate has a recess surrounding the semiconductor element on a surface to be bonded to the semiconductor element.

2. 2. The semiconductor device according to claim 1, wherein the position of the wall of the recess on the side closer to the semiconductor element and the position of the outer edge of the bonding material at least partially coincide with each other.

3. 2. The semiconductor device according to claim 1, wherein the bottom surface of the recess has a roughened structure.

4. 2. The semiconductor device according to claim 1, wherein the semiconductor element is an element made of a compound semiconductor.

5. An electrical device comprising the semiconductor device according to claim 1 .

6. A method for manufacturing a semiconductor device including a substrate, a semiconductor element bonded to the substrate with a bonding material, and a resin sealant that seals the substrate and the semiconductor element with resin, a bonding step of bonding the semiconductor element to the substrate with the bonding material; a recess forming step of removing the bonding material that has protruded around the periphery of the semiconductor element in the bonding step and a part of the surface of the substrate to form a recess that closely surrounds the periphery of the semiconductor element; a resin sealing step of sealing the substrate and the semiconductor element with resin; 1. A method for manufacturing a semiconductor device, comprising:

7. 7. The method for manufacturing a semiconductor device according to claim 6, wherein the recess forming step includes irradiating a laser to remove the bonding material that has protruded around the semiconductor element and a part of the surface of the substrate.

8. 7. The method for manufacturing a semiconductor device according to claim 6, wherein the bottom surface of the recess is roughened.

9. 9. The method for manufacturing a semiconductor device according to claim 6, wherein the semiconductor element is an element made of a compound semiconductor.

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