Power device and method for manufacturing power device

Abstract

This power device (1000) is provided with: a heat sink (1); a vibration absorbing member (2) that is disposed on the heat sink (1) and that absorbs vibration transmitted from the outside; and a semiconductor device (100) disposed on the vibration absorbing member (2), having a thermally conductive insulating member (16) provided on the bottom surface side, and disposed on the heat sink (1) via the vibration absorbing member (2), the vibration absorbing member (2) functioning so as to attenuate vibration energy of vibration transmitted from the heat sink (1) to the semiconductor device (100) due to vibration from the outside.

Description

Technical Field

[0001] This disclosure relates to a power equipment and a method for manufacturing the power equipment. Background Technology

[0002] Electrical equipment incorporating semiconductor devices is used in the power control of a wide range of devices, from industrial equipment to home appliances, automobiles, and trams. An example of such equipment is an inverter that converts direct current to alternating current. Electrical equipment may operate in harsh environments such as high or low temperatures, low pressure, or vibration, thus requiring stable reliability even under these conditions. In particular, high-voltage driven electrical equipment needs to efficiently dissipate the heat generated by the operation of the semiconductor devices within it to the outside of the equipment while ensuring reliable insulation.

[0003] For example, the semiconductor module unit described in Patent Document 1 has the following structure: a thermally conductive insulating sheet of a semiconductor device (power element) is bonded to a heat sink (heat diffuser) via a thermally conductive layer (reactive grease, solvent-diluted grease), and then the semiconductor device is pressed against the heat sink by a disc spring. In the semiconductor module unit of Patent Document 1, while ensuring insulation reliability through the thermally conductive insulating sheet, the bonding stability between the semiconductor device and the heat sink is ensured by the disc spring and the thermally conductive layer.

[0004] Patent Document 1: Japanese Patent No. 5383599 Summary of the Invention

[0005] The problem the invention aims to solve

[0006] However, in the semiconductor module unit described in Patent Document 1, vibration energy is transferred from the heat sink to the semiconductor device without attenuation. Therefore, there is a possibility of damage to components within the semiconductor device due to external vibration, resulting in a decrease in insulation reliability. In particular, the thermally conductive insulating sheet of the semiconductor device plays both the role of heat exchange with the heat sink and ensuring insulation reliability. Therefore, if the thermally conductive insulating sheet is damaged, that is, if the thermally conductive insulating sheet is cracked, missing, has a fissure, or peels off, there is a problem that the insulation reliability of the semiconductor device will decrease significantly.

[0007] This disclosure was made to solve the problems described above, and aims to obtain a power device with excellent long-term insulation reliability by attenuating the vibrational energy applied to the mounted semiconductor device.

[0008] Solution for solving the problem

[0009] The power equipment based on this disclosure has the following features:

[0010] heat sink;

[0011] A vibration-absorbing component, disposed on the heat sink, absorbs vibration; and

[0012] A semiconductor device is disposed on the vibration-absorbing member.

[0013] The method for manufacturing power equipment based on this disclosure includes:

[0014] The process of forming vibration-absorbing components on a radiator; and

[0015] The process of forming the vibration-absorbing member on the bottom surface of the semiconductor device facing the heat sink.

[0016] The effects of the invention

[0017] According to the power equipment based on this disclosure, by arranging a vibration absorbing member between the thermally conductive insulating member of the semiconductor device and the heat sink, the vibration energy applied to the semiconductor device, especially the thermally conductive insulating member disposed on the bottom side of the semiconductor device, can be attenuated, thus achieving the effect of preventing damage to the components of the power equipment and maintaining long-term insulation reliability. Attached Figure Description

[0018] Figure 1 This is a side view of the power equipment involved in Embodiment 1.

[0019] Figure 2 This is a top view of the power equipment involved in Implementation Method 1.

[0020] Figure 3 The electrical equipment involved in Implementation Method 1 is along Figure 2 The cross-sectional view of line AA is shown.

[0021] Figure 4 This is an example of calculating the maximum electric field strength when the thickness of the vibration-absorbing component of the power equipment involved in Embodiment 1 is equal to the thickness of the thermally conductive insulating component of the semiconductor device.

[0022] Figure 5 This is a calculation example of the maximum electric field strength when the thickness of the vibration absorbing component of the power equipment involved in Embodiment 1 is twice the thickness of the thermally conductive insulating component of the semiconductor device.

[0023] Figure 6 This is a flowchart illustrating the manufacturing method of the power equipment involved in Embodiment 1.

[0024] Figure 7 This is a flowchart illustrating a variation of the method for manufacturing the power equipment according to Embodiment 1.

[0025] Figure 8 This is a top view of the electrical equipment involved in a variation of Embodiment 1, Example 1.

[0026] Figure 9 This is a side view of the electrical equipment involved in Variation 2 of Embodiment 1.

[0027] Figure 10 This is a side view of the power equipment involved in Embodiment 2.

[0028] Figure 11 This is a side view of the electrical equipment involved in a variation of Embodiment 2, Example 1.

[0029] Figure 12 This is a side view of the electrical equipment involved in a variation of embodiment 2, example 2.

[0030] Figure 13 This is a side view of the power equipment involved in Embodiment 3.

[0031] Figure 14 This is a side view of the electrical equipment involved in a variation of Embodiment 3, Example 1.

[0032] Figure 15 This is a side view of the power equipment involved in Embodiment 4.

[0033] Figure 16 This is a top view of the power equipment involved in Implementation Method 4. Detailed Implementation

[0034] Implementation method 1.

[0035] Figure 1 This is a side view of the power equipment 1000 according to Embodiment 1. Figure 2 This is a top view of the power equipment 1000 according to Embodiment 1. Figure 3 It is along the electrical equipment 1000 involved in Embodiment 1 Figure 2 The cross-sectional view of line AA is shown.

[0036] The power equipment 1000 according to Embodiment 1 includes a heat sink 1, a vibration absorbing member 2, and a semiconductor device 100. The semiconductor device 100 includes a semiconductor chip 11, a lead frame 12, a heat spreader 13, a sealing part 14, a wire 15, and a thermally conductive insulating member 16.

[0037] like Figure 1As shown, the power equipment 1000 has a vibration-absorbing member 2 disposed on a heat sink 1, and a semiconductor device 100 disposed on the vibration-absorbing member 2. That is, the power equipment 1000 has a structure in which the vibration-absorbing member 2 is disposed between the semiconductor device 100 and the heat sink 1. Furthermore, the semiconductor device 100 is connected to the heat sink 1 via the vibration-absorbing member 2.

[0038] like Figure 3 As shown, the semiconductor device 100 includes the following structure: a thermal diffuser 13 is disposed on a thermally conductive insulating member 16, a semiconductor chip 11 is disposed on the thermal diffuser 13, a wire 15 with one end connected to the semiconductor chip 11 is connected to one end of a lead frame 12, the above-mentioned components are sealed by a sealing part 14, and the other end of the lead frame 12 protrudes from the sealing part 14.

[0039] The radiator 1 is a component responsible for dissipating heat from the electrical equipment 1000. Copper, aluminum, or other metals with high thermal conductivity are preferred as materials for the radiator 1. Furthermore, alloys of these highly thermally conductive metals can also function as radiators 1. By connecting the radiator 1 to a structure with a large surface area, such as heat dissipation fins (not shown), the heat generated from the electrical equipment 1000 can be dissipated more efficiently. Additionally, by integrating the radiator 1 with the heat dissipation fins into a single structure, the heat dissipation of the electrical equipment 1000 can be further improved in terms of efficiency.

[0040] The vibration absorbing member 2 attenuates the vibration energy transmitted to the semiconductor device 100 via the heat sink 1, and also serves to dissipate heat generated in the semiconductor device 100, which is a heat source, to the heat sink 1. Examples of materials constituting the vibration absorbing member 2 include viscoelastic materials such as silicone gel, polyurethane gel, and polyacrylamide gel. Alternatively, a mixture of these materials with added thermally conductive materials such as silica, alumina, aluminum nitride, silicon nitride, carbon, and copper can be used to constitute the vibration absorbing member 2.

[0041] The viscoelastic material used as the constituent material of vibration-absorbing component 2 is a substance that possesses both the viscosity to absorb vibrations from the outside and the elasticity to maintain its original shape. Regarding the vibration σ of the substance when a sinusoidal strain γ = γ0sinωt is applied, it is expressed as σ = σ0sinωt in the case of an elastic body, and as σ = σ0sin(ωt + π / 2) in the case of a viscous body. On the other hand, the viscoelastic body exhibits behavior between an elastic body and a viscous body. That is, the viscoelastic body can attenuate the energy generated by vibration.

[0042] The energy loss G per cycle of vibration deformation of a viscoelastic body is expressed as G=(σ0 / γ0)×sinδ, and the loss coefficient is expressed as tanδ (0<δ<π / 2). A larger loss coefficient is preferred. When using viscoelastic materials other than those exemplified above, such as rubber, gels, or elastomers, as the constituent material of the vibration absorbing member 2, a material with a loss coefficient of 0.2 or higher is preferred. Furthermore, the thickness of the vibration absorbing member 2 can be designed considering only heat dissipation and insulation reliability. Additionally, anti-vibration gels can be used as gels, and anti-vibration rubbers as rubbers to further improve the vibration damping performance of the vibration absorbing member 2. Specific examples of anti-vibration rubbers include acrylic rubber, silicone rubber, and fluororubber, which have excellent heat resistance; butyl rubber with high attenuation and butadiene rubber with a low dynamic-to-static stiffness ratio are also examples. Specific examples of anti-vibration gels include silicone gels.

[0043] exist Figure 4 The calculation examples of the maximum electric field strength when the thickness of the vibration absorbing member 2 is equal to the thickness of the thermally conductive insulating member 16 are shown separately for the cases without bubbles and the cases without bubbles. Figure 5 The calculation examples of the maximum electric field strength when the thickness of the vibration absorbing member 2 is twice the thickness of the thermally conductive insulating member 16 are shown separately for the cases without bubbles and the cases without bubbles. In addition, bubbles refer to bubbles generated inside the vibration absorbing member 2. Figure 4 and Figure 5 The value on the vertical axis is the ratio of the maximum electric field strength in the case where vibration-absorbing member 2 is absent, as shown as the default value. Furthermore, ε s ε represents the relative permittivity of vibration absorbing component 2. m This represents the relative permittivity of the thermally conductive insulating component 16.

[0044] It can be known that in ε s ≤3ε m When the vibration absorbing member 2 is not present, the ratio of the maximum electric field strength is less than 0.8, and the electric field mitigation effect is significant. The thicker the vibration absorbing member 2, the lower the maximum electric field strength. In addition, since the vibration absorbing member 2 is in direct contact with the semiconductor device 100, which is a heat source, it is necessary to maintain its function even when exposed to high temperatures for a long period of time, which is equivalent to the product life.

[0045] When the electrical equipment 1000 is used beyond the heat resistance of the vibration absorbing member 2, the vibration absorbing member 2 suffers adverse conditions such as thickness reduction due to sol-forming or liquefaction, component leaching, and decreased insulation reliability due to chemical reactions with other components, significantly impairing its function as a vibration absorber. Therefore, the preferred material for constituting the vibration absorbing member 2 is a material with a margin of 10°C or more before the points of change in physical properties such as glass curing temperature and sol-forming temperature.

[0046] Furthermore, when applying the vibration absorbing member 2 to a semiconductor device 100 that does not have a thermally conductive insulating member 16, the vibration absorbing member 2 needs to also function as a thermally conductive insulating member 16. Therefore, as the constituent material of the vibration absorbing member 2, a volume resistivity of 10 Ω·cm is used within the driving temperature range of the power device 1000. 10 The viscoelastic material has physical properties of 20 or less and a relative permittivity of 20 or less. The constituent material of the vibration absorbing member 2 can be selected as described above, and the thickness of the vibration absorbing member 2 can be designed. As an example of the design, the thickness d of the vibration absorbing member 2 is... s and the thickness d of the thermally conductive insulating component 16 m Designed to have d s ≥d m The relationship is sufficient.

[0047] like Figure 3 As shown, the semiconductor device 100 has at least one semiconductor chip 11, and the inner and outer sides of the semiconductor device 100 are electrically connected by a lead frame 12. Other structural elements of the semiconductor device 100 may vary depending on the intended use, and can therefore be appropriately configured.

[0048] Examples of semiconductor chips 11 mounted on the semiconductor device 100 include IGBTs (Insulated Gate Transistors), MOS-FETs (Metal-Oxide-Semiconductor Field-Effect Transistors), diodes, and other semiconductor components used for high-current control.

[0049] The semiconductor material constituting the semiconductor chip 11 is generally Si (silicon). Alternatively, the semiconductor chip 11 may also be composed of wide-bandgap semiconductor materials such as SiC (silicon carbide), GaN (gallium nitride), and C (diamond), which are semiconductor materials used to constitute high-output semiconductor chips.

[0050] Compared to a semiconductor chip 11 made of Si, a semiconductor chip 11 with a wide bandgap semiconductor as its constituent material has lower power loss and can operate at higher temperatures, thus enabling miniaturization of both the semiconductor device 100 itself and the power equipment 1000 equipped with the semiconductor device 100. Figure 3 The diagram illustrates an example of a power device 1000 containing a single semiconductor chip 11, but multiple semiconductor chips 11 can also be incorporated into a power device 1000, as will be described later.

[0051] The lead frame 12 is a component that provides electrical connection between the inner and outer sides of the semiconductor device 100. Therefore, the preferred material for the lead frame 12 is a metal with high electrical conductivity, such as gold, copper, or aluminum, or an alloy of these metals. Figure 3 In one example of the semiconductor device 100 shown, the lead frame 12 protrudes outward from the side of the semiconductor device 100 in an L-shape. Besides this example, the lead frame 12 can function as a lead frame 12 even if it protrudes upward from the upper surface of the semiconductor device 100. Furthermore, it can function as a lead frame 12 even in a straight line shape or other shapes.

[0052] The heat diffuser 13 is a component used to dissipate heat generated from the semiconductor chip 11 to the outside of the semiconductor device 100. As the constituent material of the heat diffuser 13, metals with high thermal conductivity, such as copper and aluminum, are preferred. Alternatively, alloys of these metals can also be used to construct the heat diffuser 13. Figure 3 In this design, the heat diffuser 13 and the lead frame 12 are independent of each other, but they can also be an integral structure.

[0053] The sealing portion 14 insulates the inner and outer sides of the semiconductor device 100 by covering the entire semiconductor chip 11, heat diffuser 13, wire 15, and part of the lead frame 12. The sealing portion 14 suffers from reduced insulation reliability due to peeling, bubbles, foreign matter intrusion, etc. Therefore, it is desirable to manufacture the semiconductor device 100, for example, by using transfer molding with a mold.

[0054] The sealing part 14 can be made of resins with excellent insulating properties such as epoxy, polyimide, polyamide, and polyamide-imide, or mixtures of these resins with added silica, alumina, aluminum nitride, or boron nitride. Regarding the volume resistivity of these materials, as long as it is within the operating temperature range of the electrical equipment 1000, the volume resistivity is 10 Ω·cm. 10 Ω Materials with a diameter of 1 cm or more and a relative permittivity of 20 or less are acceptable, such as SF6, nitrogen, or other gases or materials not mentioned above.

[0055] The lead wire 15 electrically connects the semiconductor chip 11 to the lead frame 12. The lead wire 15 is preferably made of a metal with high conductivity, such as gold, copper, or aluminum, or an alloy of metals with high conductivity. However, the lead frame 12 may also be directly bonded to the semiconductor chip 11 without using the lead wire 15.

[0056] Additionally, wire 15 is sometimes used as a signal line to control the power of semiconductor chip 11. When wire 15 is used as a signal line, it serves to transmit control signals from outside the semiconductor device 100 to semiconductor chip 11 via control terminals (not shown) and wire 15. Furthermore, in Figure 3 The lead frame 12 can be directly attached to the heat diffuser 13, but the electrical connection between the heat diffuser 13 and the lead frame 12 can also be made via the wire 15.

[0057] The thermally conductive insulating member 16 is thermally bonded to the heat diffuser 13. The thermally conductive insulating member 16 is a component used to insulate the inner and outer sides of the semiconductor device 100 while dissipating heat generated within the semiconductor device 100. The thermally conductive insulating member 16 is made of an insulating resin sheet or a thin sheet of ceramic. When the thermally conductive insulating member 16 is a resin sheet, the material used is a resin with excellent insulating properties, such as epoxy, polyimide, polyamide, or polyamide-imide, or a mixture of these resins with added silica, alumina, aluminum nitride, or boron nitride.

[0058] When using a thin ceramic sheet as the thermally conductive insulating member 16, ceramics with excellent insulation and heat dissipation properties, such as silicon dioxide, alumina, aluminum nitride, and silicon nitride, are used. To improve the insulation of the thermally conductive insulating member 16, a thicker thickness is preferable; conversely, to improve heat dissipation, a thinner thickness is desirable. Therefore, the thickness of the thermally conductive insulating member 16 can be designed considering this trade-off. The thermally conductive insulating member 16 is preferably about 20 μm to 500 μm thick, with an upper limit of about 2 mm. By using a material with excellent insulation properties in the thermally conductive insulating member 16, its thickness can be reduced. For example, a material with a volume resistivity of 10 Ω·cm is preferred as a constituent material of the thermally conductive insulating member 16. 10 Materials that are above the specified limit and have a relative permittivity of 20 or less.

[0059] <Method for manufacturing electrical equipment according to Embodiment 1>

[0060] Figure 6 This is a flowchart illustrating the manufacturing method of the power equipment involved in Embodiment 1.

[0061] In step S101, a semiconductor device 100 is manufactured. In step S102, a vibration-absorbing member 2 is formed on the heat sink 1. In step S103, the semiconductor device 100 is disposed on the vibration-absorbing member 2. In step S104, subsequent processes such as housing assembly and lead frame bonding are performed in accordance with the configuration of the power equipment 1000.

[0062] After the vibration-absorbing member 2 is formed on the heat sink 1, it is degassed and hardened. Alternatively, the vibration-absorbing member 2 can be formed on the heat sink 1 after it has been formed into a sheet shape.

[0063] <Modifications of the method for manufacturing the power equipment according to Embodiment 1>

[0064] Figure 7 This is a flowchart illustrating a variation of the method for manufacturing the power equipment according to Embodiment 1.

[0065] In step S201, semiconductor device 100 is manufactured.

[0066] In step S202, an uncured vibration-absorbing member 2 is disposed on the heat sink 1. In step S203, the uncured vibration-absorbing member 2 is coated onto the semiconductor device 100. In step S204, the semiconductor device 100 is disposed on the heat sink 1, on the uncured vibration-absorbing member 2. In step S205, the vibration-absorbing member 2 is degassed and cured. In step S206, subsequent processes such as housing assembly and lead frame joining are performed to match the configuration of the power equipment 1000.

[0067] Compared to the manufacturing method of the power equipment according to Embodiment 1, in the variation of the manufacturing method of the power equipment according to Embodiment 1, although the number of steps increases and the operation becomes more complex, the possibility of air bubbles entering the vibration absorbing member 2 can be reduced. Even omitting any step in steps S202 and S203 can achieve some degree of effect, but it is more preferable to omit steps such as... Figure 7 The process for both parties is carried out in the manner described in the flowchart.

[0068] Variation 1 of Implementation Method 1.

[0069] Figure 8 This is a top view of the power device 1100 according to a variation of Embodiment 1. The power device 1100 has multiple semiconductor devices 100 mounted on a heat sink 1 via vibration-absorbing members 2. The required number of semiconductor devices 100 are arranged on the heat sink 1 according to the required function or voltage level of the power device. Figure 8 In one example shown, a total of 16 semiconductor devices 100 are mounted in a power device 1100.

[0070] Variation 2 of Implementation Method 1.

[0071] Figure 9 This is a side view of the power device 1200 according to a variation 2 of Embodiment 1. The power device 1200 is configured for application to a double-sided cooled semiconductor device 200. The power device 1200 has a structure in which vibration-absorbing members 2 are respectively arranged on the upper and lower surfaces of the semiconductor device 200, and the semiconductor device 200 is clamped by heat sinks 1 from both the upper and lower directions. Even if only one of the two heat sinks 1 is arranged between the vibration-absorbing member 2 and the semiconductor device 100, it will have some effect. However, from the viewpoint of efficiently absorbing vibrations from the outside, it is desirable to... Figure 9 As shown, vibration absorption components 2 are respectively arranged between the two heat sinks 1 and the semiconductor device 200.

[0072] <Effects of Implementation Method 1>

[0073] According to the above, in the power equipment and the method for manufacturing the power equipment according to Embodiment 1, by arranging a vibration absorbing member between the thermally conductive insulating member of the semiconductor device and the heat sink, the vibration energy applied to the semiconductor device, especially the thermally conductive insulating member, can be attenuated. Therefore, the power equipment that can prevent the component from breaking and maintain long-term insulation reliability can be obtained, and the power equipment can be easily manufactured.

[0074] Implementation method 2.

[0075] Figure 10 This is a side view of the power equipment 1300 according to Embodiment 2. Figure 10 The power device 1300 shown includes a housing 3 as a pressing mechanism for pressing the semiconductor device 100 toward the heat sink 1. The pressing mechanism may also be other than the housing 3, such as pressing with a weight or pressing with a screw and spring mechanism, as long as it functions as a pressing mechanism.

[0076] The housing 3 is a component used to limit the movement of the semiconductor device 100 caused by vibration. In a structure where multiple semiconductor devices 100 are mounted on a single power device, such as the power device 1100 according to a variation of Embodiment 1, the pressing mechanism exemplified by the housing 3 serves to prevent the semiconductor devices 100 from contacting each other and to ensure reliable insulation. Examples of materials used to construct the housing 3 include resins with excellent insulating properties, such as epoxy, polyimide, polyamide, or polyamide-imide, or mixtures formed by adding silica, alumina, aluminum nitride, or boron nitride to resins with excellent insulating properties.

[0077] exist Figure 10The example shown is a semiconductor device 100 with a lead frame 12 protruding outwards from the housing 3. However, the lead frame 12 may not penetrate the housing 3. When the lead frame 12 protrudes outwards from the housing 3, there is greater design freedom, such as the ability to arrange other components on the outside of the housing 3. On the other hand, in a structure where the lead frame 12 does not penetrate the housing 3, while the impact of vibration energy from the housing 3 can be reduced, other components need to be placed inside the housing 3, thus reducing the design freedom of the semiconductor device 100. Furthermore, when the lead frame 12 protrudes outwards from the housing 3, by excavating a portion of the housing 3 to prevent the lead frame 12 from contacting the housing 3, the impact of vibration energy from the housing 3 can be reduced while ensuring design freedom. However, if the force used to press the vibration-absorbing member 2 against the heat sink 1 by the housing 3, which acts as a pressing mechanism, is too strong, the effectiveness of the power device 1300 according to Embodiment 2 is reduced, which is therefore not preferred.

[0078] Variation 1 of Implementation Method 2.

[0079] Figure 11 This is a side view of the power device 1400 according to a variation of Embodiment 2, Example 1. The power device 1400 has a buffer 4 disposed between the semiconductor device 100 and the housing 3 to alleviate stress. The power device 1400 achieves the following effect: while maintaining the function of the housing 3 in restricting the movement range of the semiconductor device 100, the buffer 4 alleviates the stress applied from the housing 3 to the semiconductor device 100.

[0080] As described above, the buffer 4 is a component that, while maintaining the function of limiting the movement range of the semiconductor device 100 by the housing 3, alleviates the stress that pushes the semiconductor device 100 from the housing 3 towards the heat sink 1. A foam can be cited as a constituent material of the buffer 4. Specific examples of foam include mixtures made by adding foaming agents such as N,N'-dinitrospentamethylenetetramine to resins such as polyurethane, polyethylene, natural rubber, and silicone rubber. Since the buffer 4 is in contact with the high-temperature semiconductor device 100, in the case of the above-mentioned constituent materials, a resin with excellent heat resistance, such as silicone rubber, is more preferable as the base material. Furthermore, if the surface of the buffer 4 is made adhesive, the positional displacement of the buffer 4 caused by vibration can be reduced, which is also more preferable.

[0081] Variation 2 of Implementation Method 2.

[0082] Figure 12This is a side view of the power device 1500 according to a variation of Embodiment 2. The power device 1500 has a vibration-absorbing member 2 disposed between the semiconductor device 100 and the housing 3 to mitigate stress. The power device 1500 is able to mitigate the stress applied to the semiconductor device 100 from the housing 3 by means of the vibration-absorbing member 2 while maintaining the function of the housing 3 in limiting the range of movement of the semiconductor device 100.

[0083] <Effects of Implementation Method 2>

[0084] According to the power equipment described in Embodiment 2, the movement of the semiconductor device can be restricted by pressing the semiconductor device against the pressing mechanism of the vibration absorbing member, thereby preventing damage to the member and thus maintaining the long-term insulation reliability of the power equipment.

[0085] Implementation method 3.

[0086] Figure 13 This is a side view of the power device 1600 according to Embodiment 3. The power device 1600 improves the positioning accuracy during manufacturing by forming a recess 1a in the heat sink 1. That is, the semiconductor device 100 is configured by positioning the bottom surface of the semiconductor device 100 in a manner corresponding to the recess 1a on the heat sink side, thereby improving the positioning accuracy of the semiconductor device 100 relative to the heat sink 1.

[0087] Variation 1 of Implementation Method 3.

[0088] Figure 14 This is a side view of the power equipment 1700 according to a variation of Embodiment 3, Example 1. The power equipment 1700 has the vibration-absorbing member 2 disposed only in the recess 1b of the radiator 1. By adopting this structure, the amount of components used to form the vibration-absorbing member 2 can be reduced, thus achieving the effect of reducing the manufacturing cost of the power equipment 1700.

[0089] <Effects of Implementation Method 3>

[0090] According to the power equipment of Embodiment 3, a recess is provided in the heat sink, and the bottom part of the semiconductor device is positioned in a manner corresponding to the recess on the heat sink side to arrange the semiconductor device. Therefore, it can easily obtain a power equipment that can maintain long-term insulation reliability.

[0091] Implementation method 4.

[0092] Figure 15 and Figure 16These are side and top views of the power device 1800 according to Embodiment 4. The power device 1800 reduces the vibration energy applied to the lead frame 12 by arranging legs 5 such that they fill the space between the lead frame 12 of the semiconductor device 100 and the vibration absorbing member 2. The legs 5 are configured such that one end contacts the bottom surface of the lead frame 12 and the other end contacts the surface of the vibration absorbing member 2. The legs 5 can be provided on all of the lead frames 12 of the semiconductor device 100, or they can be provided on a portion of the lead frames 12.

[0093] The lead frame 12 of the semiconductor device 100 temporarily deforms due to vibration. The amount of deformation is proportional to the length of the lead frame 12, and delamination may occur inside the semiconductor device 100 due to the deflection. Furthermore, vibration energy refers to the energy generated when the lead frame 12 vibrates due to vibration from an external source. In the power device 1800 according to Embodiment 4, by providing a leg 5 between the lead frame 12 and the vibration absorbing member 2, the vibration energy applied to the lead frame 12 can be absorbed.

[0094] In addition, in the presence of Figure 9 In the case of the double-sided cooled semiconductor device 200 of the power device 1200 according to the variation 2 of Embodiment 1 shown, the lead frame 12 of the semiconductor device 200 is relatively long for the convenience of wiring. Therefore, even small vibration energy can cause significant bending, and peeling may occur inside the semiconductor device 200. On the other hand, in the power device 1800 according to Embodiment 4, by providing a leg 5 between the lead frame 12 and the vibration absorbing member 2, the vibration energy applied to the lead frame 12 can be absorbed.

[0095] Leg 5 is a component that supports lead frame 12. As described above, it is disposed between lead frame 12 and vibration absorption member 2. Examples of materials for leg 5 include resins with excellent insulating properties, such as epoxy, polyimide, polyamide, or polyamide-imide, or mixtures made by adding silica, aluminum oxide, aluminum nitride, or boron nitride to resins with excellent insulating properties. Even if the same material as the foam used as an example of sealing part 14 is used for the purpose of lightweighting the power equipment, i.e., a mixture made by adding a foaming agent to resins such as polyurethane, polyethylene, natural rubber, or silicone rubber, it still functions as leg 5.

[0096] <Effects of Implementation Method 4>

[0097] According to the power equipment described in Embodiment 4, a leg is provided between the lead frame and the vibration absorption member, which can absorb the vibration energy applied to the lead frame, thus achieving the effect of obtaining a power equipment with better long-term insulation reliability.

[0098] This disclosure describes various exemplary embodiments and examples, but the various features, methods and functions described in one or more embodiments are not limited to the application of a particular embodiment and can be applied to the embodiment alone or in various combinations.

[0099] Therefore, numerous variations not illustrated are conceivable within the scope of this disclosure. These include variations of at least one structural element, additions, omissions, and extraction of at least one structural element combined with structural elements from other embodiments.

[0100] (Explanation of reference numerals in the attached image)

[0101] 1: Heat sink; 1a, 1b: Recess; 2: Vibration absorbing component; 3: Housing; 4: Buffer; 5: Leg; 11: Semiconductor chip; 12: Lead frame; 13: Heat diffuser; 14: Sealing part; 15: Wire; 16: Thermally conductive insulating component; 100, 200: Semiconductor device; 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800: Electrical equipment

Claims

1. An electric power device comprising: a heat sink; a vibration absorbing member configured on the heat sink to absorb vibration; and a semiconductor device configured on the vibration absorbing member.

2. The electric power device according to claim 1, wherein the semiconductor device is provided with a thermally conductive insulating member on a bottom surface side, the thermally conductive insulating member being configured on the heat sink via the vibration absorbing member.

3. The electric power device according to claim 1 or 2, wherein the vibration absorbing member is composed of a viscoelastic body.

4. The electric power device according to claim 3, wherein the viscoelastic body is any of a gel, a rubber, or an elastic material.

5. The electric power device according to claim 4, wherein the gel is any of a silicone gel, a polyurethane gel, or a polyacrylamide gel.

6. The electric power device according to claim 1 or 2, wherein the vibration absorbing member is a vibration-proof gel or a vibration-proof rubber.

7. The electric power device according to any one of claims 1 to 6, wherein a loss coefficient of the vibration absorbing member with respect to vibration is 0.2 or more.

8. The electric power device according to any one of claims 1 to 7, wherein 9. The electric power device according to claim 2, wherein 10. The electric power device according to claim 2 or 9, wherein 11. The electric power device according to any one of claims 1 to 10, wherein a pressing mechanism that presses the semiconductor device and the vibration absorbing member to the heat sink is provided.

12. The electric power device according to claim 11, wherein a buffer is provided between the semiconductor device and the pressing mechanism.

13. The electric power device according to any one of claims 1 to 12, wherein a recess having a bottom surface larger than a bottom surface of the semiconductor device is formed in a surface of the heat sink facing the bottom surface of the semiconductor device.

14. The electric power device according to claim 13, wherein the vibration absorbing member is configured only inside the recess.

15. The electric power device according to any one of claims 1 to 14, wherein the semiconductor device has a lead frame protruding from a side surface portion, and a leg portion having one end in contact with the lead frame and the other end in contact with the heat sink is provided between the lead frame and the heat sink.

16. A manufacturing method of an electric power device comprising: a step of forming a vibration absorbing member on a heat sink; and a step of forming the vibration absorbing member on a bottom surface of a semiconductor device facing the heat sink.

17. A manufacturing method of an electric power device comprising: a step of forming a vibration absorbing member on a heat sink; and a step of configuring a semiconductor device on the vibration absorbing member. The volume resistivity of the vibration absorbing member is 10 10 The above and relative dielectric constant is 20 or less.

18. The manufacturing method of an electric power device according to claim 16, wherein in the step of forming the vibration absorbing member on the heat sink, the vibration absorbing member that is not hardened is applied on the heat sink. The relative dielectric constant ε of the vibration absorbing member s The relative dielectric constant ε of the thermally conductive insulating member m has a relationship of ε s ≤ 3ε m . ​ The thickness d of the vibration absorbing member s The thickness d of the thermally conductive insulating member m has a relationship of d s ≥ d m . ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ In the process of forming the vibration absorbing member on the semiconductor device, after the vibration absorbing member is applied on the semiconductor device, the semiconductor device is arranged on the heat sink, The manufacturing method of the power device further includes a process of degassing and hardening the vibration absorbing member.

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