Semiconductor equipment

Abstract

To provide a semiconductor device that can suppress the degradation of its characteristics due to temperature cycling. [Solution] The semiconductor device comprises a frame having an inner wall surface, a semiconductor element housed in the frame, and an epoxy resin material provided within the frame, encapsulating the semiconductor element and containing a filler. The semiconductor element has a first main surface and a second main surface opposite to the first main surface. The frame has a first end closer to the first main surface than the second main surface, and a second end closer to the second main surface than the first main surface. When viewed from the first end, the semiconductor element is hidden by the epoxy resin material. The inner wall surface has a first surface whose normal vector contains a component that points toward the first end in a direction perpendicular to the first main surface. In a direction perpendicular to the first main surface, the first surface is located closer to the first end than the semiconductor element, and the epoxy resin material is in contact with the first surface.

Description

Technical Field

[0001] This disclosure relates to a semiconductor device.

Background Art

[0002] In a semiconductor device used for a power module, a semiconductor element is housed in a frame body, and the semiconductor element is sealed with a sealing resin material. An epoxy resin material is known as a sealing resin material for such applications.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

[0007] According to this disclosure, it is possible to suppress the degradation of properties associated with temperature cycling. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a plan view showing a semiconductor device according to the first embodiment. [Figure 2] Figure 2 is a cross-sectional view showing a semiconductor device according to the first embodiment. [Figure 3] Figure 3 is a cross-sectional view showing the recess in the first embodiment. [Figure 4] Figure 4 is a cross-sectional view showing the recess in the second embodiment. [Figure 5] Figure 5 is a plan view showing a semiconductor device according to the third embodiment. [Figure 6] Figure 6 is a cross-sectional view showing a semiconductor device according to the third embodiment. [Figure 7] Figure 7 is a cross-sectional view showing the convex portion in the third embodiment. [Figure 8] Figure 8 is a cross-sectional view showing the recess in the fourth embodiment. [Figure 9] Figure 9 is a cross-sectional view showing the convex portion in the fifth embodiment.

Mode for Carrying Out the Invention

[0009] The mode for carrying out the invention will be described below.

[0010] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described. In the following description, the same or corresponding elements are denoted by the same reference numerals, and the same description thereof will not be repeated. In the following description, the XYZ orthogonal coordinate system is used, but this coordinate system is defined for the purpose of explanation and does not limit the posture of the semiconductor device. Also, depending on the view point, the +Z side may be referred to as the upper side, the upper portion or the top, and the -Z side may be referred to as the lower side, the lower portion or the bottom. In the present disclosure, "plan view" means viewing an object from above, and "planar shape" means the shape of an object viewed from above.

[0011] [1] A semiconductor device according to one aspect of the present disclosure includes a frame body having an inner wall surface, a semiconductor element housed in the frame body, and an epoxy resin material provided in the frame body for sealing the semiconductor element and containing a filler. The semiconductor element has a first main surface and a second main surface opposite to the first main surface. The frame body has a first end closer to the first main surface than the second main surface and a second end closer to the second main surface than the first main surface. When viewed from the first end side, the semiconductor element is hidden by the epoxy resin material. The inner wall surface has a first surface including a component whose normal vector faces the first end side in a direction perpendicular to the first main surface. In the direction perpendicular to the first main surface, the first surface is located closer to the first end than the semiconductor element, and the epoxy resin material contacts the first surface.

[0012] When the semiconductor element repeatedly turns on and off, the epoxy resin material repeatedly expands and contracts thermally. Such repeated thermal expansion and contraction, that is, a temperature cycle, may cause cracks along the inner wall surface of the frame body, but the expansion of the cracks is prevented by the first surface. Therefore, deterioration of characteristics due to the temperature cycle can be suppressed.

[0013] 〔2〕In [1], the epoxy resin material may have a base portion with a flat surface on the surface, and a raised portion that rises from the base portion along the inner wall surface and has a curved surface on the surface. In this case, when thermal stress acts on the epoxy resin material due to a temperature cycle, the thermal stress concentrates on the raised portion, and it is difficult for the thermal stress to act on the base portion. Therefore, damage such as cracks in the epoxy resin material is unlikely to occur, and deterioration of characteristics associated with the temperature cycle can be suppressed.

[0014] 〔3〕In [2], in a cross-sectional view perpendicular to the first main surface, the equivalent circle diameter of the filler contained in the raised portion may all be 10 μm or less. When forming an epoxy resin material using a liquid epoxy resin containing a filler, the raised portion is formed by surface tension, but a filler with an equivalent circle diameter greater than 10 μm is unlikely to be contained in the raised portion.

[0015] 〔4〕In [3], in a cross-sectional view perpendicular to the first main surface, the base portion may contain a filler with an equivalent circle diameter exceeding 10 μm. In this case, it is easy to obtain high strength in the base portion.

[0016] 〔5〕In any one of [2] to [4], in a cross-sectional view perpendicular to the first main surface, the base portion may contain 0.1 or more fillers with an equivalent circle diameter of 5 μm or more per mm 2 This case makes it easy to obtain high strength in the base portion.

[0017] 〔6〕In any one of [2] to [5], the distance between the first surface and the flat surface of the base portion in the direction perpendicular to the first main surface may be 5 mm or less. In this case, even if there is a gap between the frame body and the epoxy resin material in a portion closer to the first end than the first surface, it is easy to suppress the spread of cracks starting from the gap.

[0018] [7] In any of [2] to [6], a recess is formed in the frame, and the recess has a first surface and a second surface that is connected to the first surface and is located closer to the first end than the first surface, and the curved surface of the raised portion may be on the inside of the recess. In this case, even if there is a gap between the frame and the raised portion, it is easier to contain the spread of cracks originating from the gap within the recess.

[0019] [8] In [7], the second surface may be parallel to the direction perpendicular to the first main surface. In this case, the shape of the recess is simple and it is easy to form the recess.

[0020] [9] In [7], the second surface may be inclined so that it is located inward of the frame as it approaches the first end. In this case, it is difficult for a raised portion to form and it is easier to suppress the occurrence of gaps.

[0021]

[10] In any of [7] to [9], a plurality of the recesses may be formed in a direction perpendicular to the first main surface. In this case, even if the liquid level of the liquid epoxy resin fluctuates during manufacturing, it is easy to position the raised portion within one of the recesses. Therefore, it is easier to more reliably suppress changes in properties due to temperature cycling.

[0022]

[11] In any of [1] to [6], a protrusion is formed on the frame, and the protrusion may have the first surface and the third surface which is connected to the first surface and is located closer to the second end than the first surface. In this case, even if there is a gap between the frame and the raised portion, the protrusion prevents the crack from spreading starting from the gap.

[0023]

[12] In

[11] , the multiple protrusions may be formed in a direction perpendicular to the first main surface. In this case, even if the liquid level of the liquid epoxy resin fluctuates during manufacturing, it is easy to position the raised portion above any of the protrusions. Therefore, it is easier to more reliably suppress changes in properties due to temperature cycling.

[0024]

[13] In any of [1] to

[12] , the first surface may be provided around the entire circumference of the inner wall surface. In this case, crack propagation is more easily suppressed.

[0025] [Embodiments of this Disclosure] (First Embodiment) A first embodiment will be described. The first embodiment relates to a semiconductor device. Figure 1 is a plan view showing a semiconductor device according to the first embodiment. Figure 2 is a cross-sectional view showing a semiconductor device according to the first embodiment. Figure 3 is a cross-sectional view showing a recess in the first embodiment. Figure 3 corresponds to an enlarged cross-sectional view of region R1 in Figure 2. Figure 2 corresponds to a cross-sectional view along the line II-II in Figure 1.

[0026] As shown in Figure 1, the semiconductor device 1 according to this embodiment includes an insulating substrate 10, conductive layers 11 and 12, bonding materials 13 and 14, external terminals 15 and 16, a die 17, a semiconductor element 20, a frame 30, and an epoxy resin material 40.

[0027] The frame 30 has an upper end 51 and a lower end 52 opposite to the upper end 51 in the Z-axis direction, i.e., the height direction. The frame 30 has an inner wall surface 30A and an outer wall surface 30B opposite to the inner wall surface 30A. The planar shape of the inner wall surface 30A and the planar shape of the outer wall surface 30B are rectangular. The detailed structure of the inner wall surface 30A will be described later. The outer wall surface 30B may have protrusions or recesses formed therein for contact with other members, etc. The material of the frame 30 is, for example, a thermoplastic resin. The material of the frame 30 may also be a super engineering plastic or an engineering plastic. Examples of super engineering plastics are amorphous polyarylate, polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide, polyetherimide, and liquid crystal polymer. Engineering plastics include, for example, polyacetal, polyamide, polycarbonate, modified polyphenylene ether, polybutylene terephthalate, glass fiber reinforced polyethylene terephthalate, ultra-high molecular weight polyethylene, and syndiotactic polyethylene. The material of the frame 30 may be, for example, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl acetate, acrylonitrile butadiene styrene, or acrylic. The upper end 51 is an example of a first end, and the lower end 52 is an example of a second end.

[0028] The insulating substrate 10 is housed in a frame 30. The insulating substrate 10 has a main surface 10A and a main surface 10B opposite to the main surface 10A. The main surface 10A is the top surface, and the main surface 10B is the bottom surface. The material of the insulating substrate 10 is, for example, silicon nitride (SiN), aluminum oxide (Al2O3), or aluminum nitride (AlN). A conductive layer 11 is provided on the main surface 10A, and a conductive layer 12 is provided on the main surface 10B. The material of the conductive layers 11 and 12 is, for example, copper (Cu). The conductive layers 11 and 12 are, for example, copper plates or copper foils.

[0029] The die 17 is joined to the conductive layer 11 by a bonding material 13. The die 17 is located above the conductive layer 11. The material of the die 17 is, for example, copper. The die 17 is, for example, a copper plate. The bonding material 13 is, for example, solder or a metal sintered material.

[0030] The semiconductor element 20 is bonded to the die 17 by a bonding material 14. The semiconductor element 20 is located on the upper side of the die 17. The semiconductor element 20 is housed in a frame 30. The semiconductor element 20 has a first main surface 20A and a second main surface 20B opposite to the first main surface 20A. The first main surface 20A is the upper surface, and the second main surface 20B is the lower surface. The Z-axis direction is perpendicular to the first main surface 20A. The upper end 51 of the frame 30 is closer to the first main surface 20A than to the second main surface 20B. The lower end 52 of the frame 30 is closer to the second main surface 20B than to the first main surface 20A. The semiconductor element 20 is, for example, a field-effect transistor (FET) or an insulated gate bipolar transistor (IGBT). The semiconductor element 20 may also be a Schottky barrier diode (SBD). The bonding material 14 is, for example, solder or metal sintered material and is electrically conductive. The semiconductor element 20 has a semiconductor substrate 21, an electrode 22 provided on the upper surface of the semiconductor substrate 21, and an electrode 23 provided on the lower surface of the semiconductor substrate 21. The semiconductor substrate 21 has, for example, a silicon carbide single crystal substrate and a silicon carbide epitaxial layer provided on the silicon carbide single crystal substrate.

[0031] External terminals 15 and 16 are fixed to the frame 30. External terminal 15 and electrode 22 are connected to each other by a wire (not shown). External terminal 16 and die 17 are connected to each other by a wire (not shown). Electrode 23 is electrically connected to die 17 via bonding material 14.

[0032] The epoxy resin material 40 is provided within the frame 30 and encapsulates the semiconductor element 20. The epoxy resin material 40 contains a filler 43. The filler 43 is, for example, silicon oxide, aluminum oxide, boron nitride, aluminum nitride, graphite, carbon fiber, iron powder, calcium oxide, or magnesium oxide.

[0033] The epoxy resin material 40 has a base portion 41 and a raised portion 42. The base portion 41 has a flat surface 41A on its surface. The base portion 41 is in contact with the semiconductor element 20. The raised portion 42 rises from the base portion 41 in the +Z direction along the inner wall surface 30A and has a curved surface 42A on its surface. The curved surface 42A is curved so that it rises more as it approaches the inner wall surface 30A.

[0034] Here, the inner wall surface 30A will be described in detail. A recess 160 is formed in the inner wall surface 30A. The recess 160 is formed in an annular shape around the entire circumference of the inner wall surface 30A in a plane parallel to the XY plane. The recess 160 has a lower surface 161, a side surface 162, and an upper surface 163. The cross-sectional shape of the recess 160 is rectangular. The lower surface 161 and the upper surface 163 face each other. The side surface 162 is located closer to the upper end 51 than the lower surface 161. The lower end of the side surface 162 is connected to the lower surface 161, and the upper end of the side surface 162 is connected to the upper surface 163. The normal vector V1 of the lower surface 161 includes a component that points toward the upper end 51 in the Z-axis direction, i.e., in the direction perpendicular to the first main surface 20A. The normal vector V1 may be parallel to the Z-axis direction, or it may be inclined from the Z-axis direction. In other words, the bottom surface 161 may or may not be perpendicular to the Z-axis direction. The side surface 162 is parallel to the Z-axis direction. The recess 160 is closer to the upper end 51 than the semiconductor element 20, and the bottom surface 161 is closer to the upper end 51 than the semiconductor element 20. The dimension S11 of the recess 160 in the Z-axis direction is, for example, 0.1 mm or more and 10 mm or less. The depth S12 of the recess 160 is, for example, 0.1 mm or more and 2 mm or less, and is 80% or less of the thickness of the portion of the frame 30 in which the recess 160 is not formed. The bottom surface 161 is an example of a first surface, and the side surface 162 is an example of a second surface.

[0035] The epoxy resin material 40 is embedded in a portion of the recess 160, and the epoxy resin material 40 is in contact with the lower surface 161. Also, the curved surface 42A of the raised portion 42 is on the inside of the recess 160. At least a portion of the upper surface 163 is separated from the epoxy resin material 40.

[0036] A gap 45 may exist between the raised portion 42 and the side surface 162. The gap 45 connects to the curved surface 42A, and the upper end of the gap 45 has an opening.

[0037] Next, the manufacturing method of the semiconductor device 1 will be described. When manufacturing the semiconductor device 1, first, a first structure is prepared in which an insulating substrate 10, conductive layers 11 and 12, bonding materials 13 and 14, a die 17, and a semiconductor element 20 are integrated. A second structure is also prepared in which external terminals 15 and 16 and a frame 30 are integrated. Next, the first structure is housed in the second structure, and wire bonding is performed to connect the external terminal 15 and the electrode 22, and wire bonding is performed to connect the external terminal 16 and the die 17. Next, a thermosetting epoxy resin containing filler and in an uncured, liquid state is injected into the inside of the frame 30. The amount of liquid epoxy resin injected is such that the raised portion due to surface tension fits into the recess 160.

[0038] Next, the epoxy resin is cured by heat treatment to obtain an epoxy resin material 40. The heat treatment temperature at this time is, for example, 120°C to 250°C. By performing heat treatment under these conditions, surface tension acts on the liquid epoxy resin, and an epoxy resin material 40 is obtained that has a base portion 41 and a raised portion 42 and is in contact with the lower surface 161 of the recess 160. At this time, a gap 45 may be formed between the raised portion 42 and the side surface 162.

[0039] In this way, semiconductor device 1 is manufactured.

[0040] In the semiconductor device 1, when the semiconductor element 20 is operating, the semiconductor element 20 generates heat, and the temperature of the epoxy resin material 40 rises to, for example, 150°C or higher. When the semiconductor element 20 is not operating, the temperature of the epoxy resin material 40 is about the same as the ambient temperature, for example, between 10°C and 30°C. Therefore, as the semiconductor element 20 repeatedly turns on and off, the epoxy resin material 40 repeatedly undergoes thermal expansion and contraction. Such repeated thermal expansion and contraction, i.e., temperature cycling, can cause cracks to form along the inner wall surface 30A, starting from the gap 45. However, in this embodiment, the propagation of cracks is prevented by the recess 160. Therefore, according to this embodiment, deterioration of properties due to temperature cycling can be suppressed.

[0041] In particular, because the curved surface 42A of the raised portion 42 is located inside the recess 160, it is easier to contain the spread of cracks originating from the gap 45 within the recess 160.

[0042] Since the lower surface 161 of the recess 160 is provided around the entire circumference of the inner wall surface 30A, it is easier to more firmly suppress the propagation of cracks.

[0043] Furthermore, although thermal stress acts on the epoxy resin material 40 due to temperature cycling, in this embodiment, the thermal stress is concentrated in the raised portion 42, and less thermal stress acts on the base portion 41 that contacts the semiconductor element 20. Therefore, according to this embodiment, damage such as cracks in the epoxy resin material 40 is less likely to occur, and deterioration of properties due to temperature cycling can be suppressed.

[0044] The distance S13 between the lower surface 161 and the flat surface 41A of the base 41 in the Z-axis direction is, for example, 5 mm or less. In this case, even if there is a gap 45 in a part closer to the upper end 51 than the lower surface 161, it is easier to suppress the spread of cracks originating from the gap 45. Even within the recess 160, if the crack spreads widely, there is a risk that the crack will spread to a part closer to the lower end 52 than the recess 160. The distance S13 may be 3 mm or less, or 2 mm or less.

[0045] As the curved surface 42A curves upwards as it approaches the inner wall surface 30A, thermal stress tends to concentrate at the tip of the raised portion 42. In particular, the tip is less constrained by the frame, making it easier to suppress damage such as cracks caused by temperature cycling.

[0046] Because the side surface 162 of the recess 160 is parallel to the Z-axis direction, the shape of the recess 160 is simple and easy to form.

[0047] In a cross-sectional view perpendicular to the first main surface 20A, the equivalent circular diameter of the filler 43 contained in the raised portion 42 is, for example, 10 μm or less in all cases. When forming the epoxy resin material 40 using a liquid epoxy resin containing filler, the raised portion 42 is formed by surface tension as described above, but filler with an equivalent circular diameter larger than 10 μm remains in the base 41 and is less likely to be included in the raised portion 42. The equivalent circular diameter of the filler 43 contained in the raised portion 42 may be 5 μm or less, 4 μm or less, or 3 μm or less in all cases.

[0048] In a cross-sectional view perpendicular to the first main surface 20A, the base 41 contains fillers with an equivalent circular diameter of 5 μm or more, for example, at a rate of 0.1 pieces / mm². 2 The above is included. In this case, high strength can be easily obtained in the base 41. The base 41 contains 0.1 fillers / mm with an equivalent circular diameter of 10 μm or more. 2 The above may also be included, with one filler with an equivalent circular diameter of 10 μm or more per mm in the base 41. 2 The above may be included.

[0049] The height H of the raised portion 42 is, for example, 0.1 mm or more and 1.5 mm or less. If the height H of the raised portion 42 is less than 0.1 mm, there is a risk that thermal stress will easily act on the base portion 41. Also, if the height H of the raised portion 42 is greater than 1.5 mm, there is a risk that damage such as cracks will easily occur in the raised portion 42. The height H of the raised portion 42 may be 0.3 mm or more and 1.3 mm or less, or 0.5 mm or more and 1.1 mm or less.

[0050] The width W of the raised portion 42 is, for example, 0.1 mm or more and 3 mm or less. If the width W of the raised portion 42 is less than 0.1 mm, there is a risk that thermal stress will easily act on the base portion 41. Also, if the width W of the raised portion 42 is greater than 3 mm, there is a risk that damage such as cracks will easily occur in the raised portion 42. The width W of the raised portion 42 may be 0.3 mm or more and 2.5 mm or less, or 0.5 mm or more and 1.5 mm or less.

[0051] The surface roughness (arithmetic mean roughness) Ra of the inner wall surface 30A is, for example, 0.01 μm or more and 1.0 μm or less. In particular, in the portion facing the raised portion 42, the surface roughness Ra of the inner wall surface 30A is, for example, 0.01 μm or more and 1.0 μm or less. Having a surface roughness Ra of 0.01 μm or more and 1.0 μm or less for the inner wall surface 30A makes it easy to form a raised portion 42 of an appropriate size. The surface roughness Ra of the inner wall surface 30A may also be 0.03 μm or more and 0.8 μm or less, or 0.05 μm or more and 0.5 μm or less. The surface roughness Ra of the inner wall surface 30A can be measured using a tactile surface roughness measuring instrument.

[0052] The number of fillers 43 in the epoxy resin material 40 with an equivalent circle diameter of X μm or more (where X is, for example, 5 or 10) can be counted as follows: First, the base 41 or raised portion 42 is observed using a scanning electron microscope (SEM), and the number of fillers 43 with an equivalent circle diameter of X μm or more within a square field of view with sides of 100 μm is counted. Then, the number obtained in this way is measured in 1 mm². 2 Convert to the number per unit. At this time, with respect to the base 41, if there are fillers 43 with an equivalent circle diameter of 50 μm or more within a square field of view with a side length of 100 μm, count the number of fillers 43 using a square field of view with a side length greater than 100 μm, and count per 1 mm 2It may also be converted to a number per unit. Furthermore, with respect to the raised portion 42, if the raised portion 42 is small and the field of view is a square with sides of 100 μm that includes space in addition to the raised portion 42, the area of ​​the raised portion 42 in the field of view is determined, and the number of fillers 43 in that area is counted, and 1 mm 2 You can also convert it to the number per unit.

[0053] Furthermore, for fillers 43 that straddle the boundary of the field of view, if a portion of the filler 43 with a diameter of X μm or more exists within the field of view, the equivalent circle diameter is considered to be X μm or more; if no portion with a diameter of X μm or more exists, the equivalent circle diameter is considered to be less than X μm.

[0054] Furthermore, if there is a large variation in the equivalent diameter of the filler 43 across multiple fields of view, the average value across multiple fields of view, for example, five or more fields of view, can be used to determine the 1mm value. 2 You may specify the number of items.

[0055] (Second Embodiment) A second embodiment will now be described. The second embodiment differs from the first embodiment mainly in the configuration of the inner wall surface 30A. Figure 4 is a cross-sectional view showing the recess in the second embodiment.

[0056] As shown in Figure 4, in the semiconductor device 2 according to the second embodiment, a recess 260 is formed on the inner wall surface 30A in place of the recess 160. The recess 260 is formed in an annular shape around the entire circumference of the inner wall surface 30A in a plane parallel to the XY plane. The recess 260 has a lower surface 261 and a side surface 262. The cross-sectional shape of the recess 260 is triangular. The side surface 262 is located closer to the upper end 51 than the lower surface 261. The normal vector V2 of the lower surface 261 includes a component that points toward the upper end 51 in the Z-axis direction. The normal vector V2 may be parallel to the Z-axis direction or may be inclined from the Z-axis direction. In other words, the lower surface 261 may be perpendicular to the Z-axis direction or not. The side surface 262 is inclined from the Z-axis direction. The side surface 262 is inclined so that it is located inside the frame 30 as it approaches the upper end 51. The lower end of the side surface 262 is connected to the bottom surface 261, and the upper end of the side surface 262 is connected to the portion of the inner wall surface 30A parallel to the Z-axis direction. The recess 260 is closer to the top end 51 than the semiconductor element 20, and the bottom surface 261 is closer to the top end 51 than the semiconductor element 20. The dimension S21 of the recess 260 in the Z-axis direction is, for example, 0.1 mm or more and 10 mm or less. The depth S22 of the recess 260 is, for example, 0.1 mm or more and 2 mm or less, and is 80% or less of the thickness of the portion of the frame 30 in which the recess 160 is not formed. The bottom surface 261 is an example of a first surface, and the side surface 262 is an example of a second surface.

[0057] The epoxy resin material 40 is embedded in a portion of the recess 260, and the epoxy resin material 40 is in contact with the lower surface 261. Also, the curved surface 42A of the raised portion 42 is on the inside of the recess 260. At least a portion of the side surface 262 is separated from the epoxy resin material 40.

[0058] A gap 45 may exist between the raised portion 42 and the side surface 262. The gap 45 connects to the curved surface 42A, and the upper end of the gap 45 has an opening.

[0059] Other configurations of the semiconductor device 2 according to the second embodiment are the same as other configurations of the semiconductor device 1 according to the first embodiment. The semiconductor device 2 according to the second embodiment can be manufactured in the same way as the semiconductor device 1, except that the shape of the frame 30 to be prepared is different.

[0060] The same effects as the first embodiment can be obtained in the second embodiment. Furthermore, in the second embodiment, since the side surface 262 is inclined downward, the raised portion 42 is less likely to form. Therefore, it is easier to suppress the occurrence of gaps 45. Moreover, in the first embodiment, the angle between the bottom surface 161 and the side surface 162 is a right angle, whereas in the second embodiment, the angle between the bottom surface 261 and the side surface 262 is an acute angle. Therefore, it is easier to suppress the propagation of cracks originating from gaps 45.

[0061] The distance S23 between the lower surface 261 and the flat surface 41A of the base 41 in the Z-axis direction is, for example, 5 mm or less. In this case, even if there is a gap 45 in a part closer to the upper end 51 than the lower surface 261, it is easier to suppress the spread of cracks originating from the gap 45. Even within the recess 260, if the crack spreads widely, there is a risk that the crack will spread to a part closer to the lower end 52 than the recess 260. The distance S23 may be 3 mm or less, or 2 mm or less.

[0062] (Third embodiment) A third embodiment will now be described. The third embodiment differs from the first embodiment mainly in the configuration of the inner wall surface 30A. Figure 5 is a plan view showing the semiconductor device according to the third embodiment. Figure 6 is a cross-sectional view showing the semiconductor device according to the third embodiment. Figure 7 is a cross-sectional view showing the convex portion in the third embodiment. Figure 7 corresponds to an enlarged cross-sectional view of region R3 in Figure 6. Figure 6 corresponds to a cross-sectional view along the line VI-VI in Figure 5.

[0063] As shown in Figures 5 to 7, in the semiconductor device 3 according to the third embodiment, a protrusion 360 is formed on the inner wall surface 30A instead of a recess 160. The protrusion 360 is formed in an annular shape around the entire circumference of the inner wall surface 30A in a plane parallel to the XY plane. The protrusion 360 has a lower surface 361, a side surface 362, and an upper surface 363. The cross-sectional shape of the protrusion 360 is rectangular. The side surface 362 is located closer to the upper end 51 than the lower surface 361. The lower end of the side surface 362 is connected to the lower surface 361, and the upper end of the side surface 362 is connected to the upper surface 363. The normal vector V3 of the upper surface 363 includes a component that points toward the upper end 51 in the Z-axis direction. The normal vector V3 may be parallel to the Z-axis direction, or it may be inclined from the Z-axis direction. In other words, the upper surface 363 may be perpendicular to the Z-axis direction, or it may not be perpendicular. The side surface 362 is parallel to the Z-axis direction. The protrusion 360 is closer to the upper end 51 than the semiconductor element 20, and the upper surface 363 is closer to the upper end 51 than the semiconductor element 20. The dimension S31 of the protrusion 360 in the Z-axis direction is, for example, 0.1 mm or more and 2 mm or less. The amount of protrusion S32 of the protrusion 360 is, for example, 0.1 mm or more and 10 mm or less. The upper surface 363 is an example of a first surface, and the side surface 362 is an example of a third surface.

[0064] The epoxy resin material 40 covers the protrusion 360, and the epoxy resin material 40 is in contact with the upper surface 363. Also, the curved surface 42A of the raised portion 42 is above the protrusion 360. Above the protrusion 360, there may be a gap 45 between the raised portion 42 and the inner wall surface 30A. The gap 45 connects to the curved surface 42A, and the upper end of the gap 45 has an opening.

[0065] Other components of the semiconductor device 3 according to the third embodiment are the same as other components of the semiconductor device 1 according to the first embodiment. The semiconductor device 3 according to the third embodiment can be manufactured in the same way as the semiconductor device 1, except that the shape of the prepared frame 30 is different. The liquid epoxy resin is injected in an amount such that the raised portion due to surface tension spreads above the protrusion 360.

[0066] In the semiconductor device 3, cracks originating from the gap 45 may occur along the inner wall surface 30A, but in this embodiment, the propagation of cracks is prevented by the protrusion 360. Therefore, even in this embodiment, deterioration of characteristics due to temperature cycling can be suppressed.

[0067] The upper surface 363 of the protrusion 360 is provided around the entire circumference of the inner wall surface 30A, making it easier to more firmly suppress the propagation of cracks.

[0068] The distance S33 between the upper surface 363 and the flat surface 41A of the base 41 in the Z-axis direction is, for example, 5 mm or less. In this case, even if there is a gap 45 in a part closer to the upper end 51 than the upper surface 363, it is easier to suppress the spread of cracks originating from the gap 45. If a crack spreads widely even above the protrusion 360, there is a risk that the crack will spread to a part closer to the lower end 52 than the protrusion 360. The distance S33 may be 3 mm or less, or 2 mm or less.

[0069] (Fourth Embodiment) A fourth embodiment will now be described. The fourth embodiment differs from the first embodiment mainly in the configuration of the inner wall surface 30A. Figure 8 is a cross-sectional view showing a recess in the fourth embodiment.

[0070] As shown in Figure 8, in the semiconductor device 4 according to the fourth embodiment, a plurality of recesses 160 are formed on the inner wall surface 30A, aligned in the Z-axis direction. The epoxy resin material 40 is embedded in a portion of one of the recesses 160, and the epoxy resin material 40 is in contact with the lower surface 161 of the recess 160. In addition, the curved surface 42A of the raised portion 42 is on the inside of the recess 160, and at least a portion of the upper surface 163 of the recess 160 is separated from the epoxy resin material 40.

[0071] If there is a recess 160 closer to the lower end 52 than the recess 160 in which the epoxy resin material 40 has partially entered, the recess 160 closer to the lower end 52 than the recess 160 in which the epoxy resin material 40 has partially entered may be filled with the epoxy resin material 40.

[0072] Furthermore, if there is a recess 160 closer to the upper end 51 than the recess 160 in which the epoxy resin material 40 is partially filled, the epoxy resin material 40 does not need to be present inside the recess 160 that is closer to the upper end 51 than the recess 160 in which the epoxy resin material 40 is partially filled.

[0073] Other configurations of the semiconductor device 4 according to the fourth embodiment are the same as other configurations of the semiconductor device 1 according to the first embodiment. The semiconductor device 4 according to the fourth embodiment can be manufactured in the same way as the semiconductor device 1, except that the shape of the frame 30 to be prepared is different.

[0074] The same effects as the first embodiment can be obtained with the fourth embodiment. Furthermore, in the fourth embodiment, since a plurality of recesses 160 are formed on the inner wall surface 30A, even if the liquid level of the liquid epoxy resin fluctuates during manufacturing, it is easy to position the raised portion 42 within one of the recesses 160. Therefore, it is easier to more reliably suppress changes in properties due to temperature cycling.

[0075] Multiple recesses 260 may be formed instead of multiple recesses 160.

[0076] (Fifth embodiment) A fifth embodiment will now be described. The fifth embodiment differs from the third embodiment mainly in the configuration of the inner wall surface 30A. Figure 9 is a cross-sectional view showing the protrusion in the fifth embodiment.

[0077] As shown in Figure 9, in the semiconductor device 5 according to the fifth embodiment, a plurality of protrusions 360 are formed on the inner wall surface 30A, arranged in the Z-axis direction. The epoxy resin material 40 covers one or more of the protrusions 360, and the epoxy resin material 40 is in contact with the upper surface 363. In addition, the curved surface 42A of the raised portion 42 is located above the uppermost protrusion 360 among the protrusions 360 covered by the epoxy resin material 40.

[0078] Other configurations of the semiconductor device 5 according to the fifth embodiment are the same as other configurations of the semiconductor device 1 according to the first embodiment. The semiconductor device 4 according to the fourth embodiment can be manufactured in the same way as the semiconductor device 3, except that the shape of the frame 30 to be prepared is different.

[0079] The same effects as the first embodiment can be obtained with the fifth embodiment. Furthermore, in the fifth embodiment, since multiple protrusions 360 are formed on the inner wall surface 30A, even if the liquid level of the liquid epoxy resin fluctuates during manufacturing, it is easy to position the raised portion 42 above any of the protrusions 360. Therefore, it is easier to more reliably suppress changes in properties due to temperature cycling.

[0080] Although embodiments have been described in detail above, this disclosure is not limited to any particular embodiment, and various modifications and changes are possible within the scope of the claims. [Explanation of Symbols]

[0081] 1, 2, 3, 4, 5: Semiconductor devices 10: Insulating substrate 10A, 10B: Main surface 11, 12: Conductive layer 13, 14: Bonding material 15, 16: External terminals 17: Die 20: Semiconductor elements 20A: First main surface 20B: 2nd main surface 21: Semiconductor substrates 22, 23: Electrode 30:Frame body 30A: Interior wall surface 30B: External wall surface 40: Epoxy resin material 41: Base 41A:Flat surface 42: Excitement Club 42A: Curved surface 43: Filler 45: Gap 51: Upper end (first end) 52: Bottom end (second end) 160, 260: concave part 161, 261: Below (page 1) 162, 262: Side view (second side) 163: Above 360:convex part 361: Below 362: Side View (3rd View) 363: Above (Page 1) R1, R3: Domains

Claims

1. A frame having an inner wall surface, A semiconductor element housed in the aforementioned frame, Provided within the frame, encapsulating the semiconductor element, and comprising an epoxy resin material containing filler, It has, The semiconductor element has a first main surface and a second main surface opposite to the first main surface. The frame has a first end that is closer to the first main surface than the second main surface, and a second end that is closer to the second main surface than the first main surface. When viewed from the first end, the semiconductor element is hidden within the epoxy resin material. The inner wall surface has a first surface whose normal vector includes a component that points toward the first end side in a direction perpendicular to the first principal surface, In a direction perpendicular to the first main surface, the first surface is located closer to the first end than the semiconductor element. The epoxy resin material is in contact with the first surface, which is a semiconductor device.

2. The epoxy resin material is A base having a flat surface, A raised portion that extends from the base along the inner wall surface and has a curved surface, A semiconductor device according to claim 1, having the following features.

3. The semiconductor device according to claim 2, wherein, in a cross-sectional view perpendicular to the first main surface, the equivalent circular diameter of the filler contained in the raised portion is 10 μm or less in all cases.

4. The semiconductor device according to claim 3, wherein, in a cross-sectional view perpendicular to the first main surface, the base portion contains a filler with an equivalent circular diameter of more than 10 μm.

5. In a cross-sectional view perpendicular to the first main surface, the base contains 0.1 fillers per mm with an equivalent circular diameter of 5 μm or more. ２ The semiconductor device according to claim 2 or claim 3, comprising the above.

6. The semiconductor device according to claim 2 or 3, wherein the distance between the first surface and the flat surface of the base in a direction perpendicular to the first main surface is 5 mm or less.

7. A recess is formed in the frame, The aforementioned recess is The first side and, A second surface is connected to the first surface and is located closer to the first end than the first surface, It has, The semiconductor device according to claim 2 or 3, wherein the curved surface of the raised portion is located inside the recess.

8. The semiconductor device according to claim 7, wherein the second surface is parallel to the direction perpendicular to the first main surface.

9. The semiconductor device according to claim 7, wherein the second surface is inclined to be located inward of the frame as it approaches the first end.

10. The semiconductor device according to claim 7, wherein a plurality of the recesses are formed in a direction perpendicular to the first main surface.

11. The frame has a protrusion formed on it. The aforementioned protrusion is, The first side and, A third surface is connected to the first surface and is located closer to the second end than the first surface, A semiconductor device according to any one of claims 1 to 3, having the features described above.

12. The semiconductor device according to claim 11, wherein a plurality of the protrusions are formed in a direction perpendicular to the first main surface.

13. The semiconductor device according to any one of claims 1 to 3, wherein the first surface is provided around the entire circumference of the inner wall surface.

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