Service facility and procedure for establishing a service facility

Abstract

A power device (1000) according to the present invention comprises: a heat sink (1); a vibration absorption element (2) arranged on the heat sink (1) and configured to dampen vibrations transmitted from the outside; and a semiconductor device (100) arranged on the vibration absorption element (2), comprising a thermally conductive insulating element (16) located on a bottom surface and positioned on the heat sink (1) via the vibration absorption element (2). The vibration absorption element (2) functions by damping the vibrational energy of the vibrations transmitted from the heat sink (1) to the semiconductor device (100) as a result of external vibrations.

Description

Technical field

[0001] The present invention relates to a power device and a method for manufacturing the power device. State of the art

[0002] A power device incorporating a semiconductor device is used for power control in a wide range of equipment, from industrial equipment to household applications, automobiles, and electric trains. An example of a power device incorporating a semiconductor device is an inverter, which converts direct current (DC) to alternating current (AC). Because power devices may be used in harsh environments, such as high or low temperature, low ambient pressure, or vibration, they must maintain stable reliability even in these harsh conditions. In particular, a power device operating at high voltage must ensure reliable insulation and effectively dissipate heat generated by the operation of the semiconductor device within the power device.

[0003] For example, in the semiconductor module unit described in patent document 1, a thermally conductive insulating surface of a semiconductor device (power unit) is bonded to a heat sink heat spreader via a thermally conductive layer (reactive lubricant, solvent-diluted lubricant), and the semiconductor device is further pressed against the heat sink by means of a disc spring. In the semiconductor module unit according to patent document 1, the insulation reliability is ensured by the thermally conductive insulating surface, and the bond stability between the semiconductor device and the heat sink is ensured by the disc spring and the thermally conductive layer. Bibliography Patent document

[0004] Patent document 1: Japanese patent JP 5 383 599 B2 Summary of the invention Problems to be solved with the invention

[0005] However, in the semiconductor module unit described in patent document 1, vibrational energy is transferred from the heat sink to the semiconductor device without being damped. This can lead to a problem whereby components within the semiconductor device are damaged by external vibrations, resulting in a reduction of insulation reliability.

[0006] In particular, the thermally conductive insulating sheet of the semiconductor device plays a role both in heat exchange with the heat sink and in ensuring insulation reliability. If the thermally conductive insulating sheet is damaged, i.e., if it is cracked, chipped, torn, peeled, or similarly damaged, then the insulation reliability of the semiconductor device is significantly reduced.

[0007] The present invention was designed to solve the problems described above, and it is an object of the present invention to provide a power device which has excellent long-term insulation reliability by damping the vibrational energy acting on an installed semiconductor device. Ways to solve the problem

[0008] A power device according to the present invention comprises: a heat sink, a vibration absorption element arranged on the heat sink and absorbing vibrations, and a semiconductor device arranged on the vibration absorption element.

[0009] A method for manufacturing a power device according to the present invention comprises: a step for forming a vibration absorption element on a heat sink and a step for forming the vibration absorption element on a bottom surface - opposite the heat sink - of a semiconductor device. Effect of the invention

[0010] In the power supply unit of the present invention, the following applies: By arranging the vibration absorption element between the thermally conductive insulating element of the semiconductor device and the heat sink, the vibration energy acting on the semiconductor device, in particular on the thermally conductive insulating element located on the bottom surface of the semiconductor device, can be dampened. This prevents damage to the components of the power supply unit and maintains long-term insulation reliability. Brief description of the drawings Fig. 1 is a side view of a power unit according to embodiment 1; Fig. 2 is a top view of the power unit according to embodiment 1; Fig. Figure 3 is a cross-sectional view of the power unit according to embodiment 1 along line AA, which is in Fig. 2 is shown; Fig. Figure 4 is a calculation example of the maximum electric field strength when the thickness of a vibration absorption element of the power device according to embodiment 1 is equal to the thickness of a thermally conductive insulating element of a semiconductor device; Fig. Figure 5 is a calculation example of the maximum electric field strength when the thickness of the vibration absorption element of the power device according to embodiment 1 is twice the thickness of the thermally conductive insulating element of the semiconductor device; Fig. Figure 6 is a flowchart describing a method for manufacturing the power unit according to embodiment 1; Fig. Figure 7 is a flowchart to describe a modification of the method for manufacturing the power unit according to embodiment 1; Fig. Figure 8 is a top view of a power unit according to modification 1 of embodiment 1; Fig. Figure 9 is a side view of a power unit according to modification 2 of embodiment 1; Fig. 10 is a side view of a power unit according to embodiment 2; Fig. 11 is a side view of a power unit according to modification 1 of embodiment 2; Fig. Figure 12 is a side view of a power unit according to modification 2 of embodiment 2; Fig. 13 is a side view of a power unit according to embodiment 3; Fig. 14 is a side view of a power unit according to modification 1 of embodiment 3; Fig. 15 is a side view of a power unit according to embodiment 4; Fig. Figure 16 is a top view of the power unit according to embodiment 4. Description of embodiments Embodiment 1

[0011] Fig. Figure 1 is a side view of a power unit 1000 according to embodiment 1. Fig. Figure 2 is a top view of the power unit 1000 according to embodiment 1, and Fig. Figure 3 is a cross-sectional view of the power unit 1000 according to embodiment 1 along line AA, which is in Fig. 2 is shown.

[0012] The power unit 1000 according to embodiment 1 comprises a heat sink 1, a vibration absorption element 2, and a semiconductor device 100. The semiconductor device 100 comprises a semiconductor chip 11, a conductor frame 12, a heat spreader 13, a sealing element 14, a wire 15, and a thermally conductive insulating element 16.

[0013] As in Fig. As shown in Figure 1, in the power unit 1000, the vibration absorption element 2 is arranged on the heat sink 1, and the semiconductor device 100 is arranged on the vibration absorption element 2. That is, the power unit 1000 has a configuration in which the vibration absorption element 2 is arranged between the semiconductor device 100 and the heat sink 1. It should be noted that the semiconductor device 100 is bonded to the heat sink 1 via the vibration absorption element 2.

[0014] As in Fig. As shown in Figure 3, the semiconductor device 100 has a configuration in which the heat distributor 13 is arranged on the thermally conductive insulating element 16, the semiconductor chip 11 is arranged on the heat distributor 13, one end of the wire 15 is connected to the semiconductor chip 11 and the other end of the wire 15 is connected to one end of the conductor frame 12, the above-mentioned components being sealed by means of the sealing element 14, and the other end of the conductor frame 12 protrudes from the sealing element 14.

[0015] The heat sink 1 is a component responsible for dissipating heat from the power unit 1000. A suitable material for the heat sink 1 is a metal with high thermal conductivity, such as copper or aluminum. An alloy of these metals with high thermal conductivity can also function as the heat sink 1.

[0016] By connecting the heat sink 1 to a structure with a large surface area, such as a heat-dissipating fin or lamella (not shown), the heat generated by the power unit 1000 can be dissipated even more effectively. By integrating the heat sink 1 with the heat-dissipating fin, the heat dissipation from the power unit 1000 can be carried out even more effectively.

[0017] The vibration absorption element 2 dampens the vibration energy transmitted to the semiconductor device 100 via the heat sink 1. The vibration absorption element 2 also serves as a heat dissipation element to the heat sink 1 during the operation of the semiconductor device 100, which acts as a heat source. Examples of materials used to form the vibration absorption element 2 include viscoelastic materials such as silicone gel, urethane gel, and polyacrylamide gel. The vibration absorption element 2 can also be configured using a mixture prepared by adding a material with excellent thermal conductivity, such as silicon dioxide, aluminum oxide, aluminum nitride, silicon nitride, carbon, or copper.

[0018] A viscoelastic material, as a component of the vibration absorption element 2, is a substance that combines viscosity, which absorbs external vibrations, and elasticity, which retains its original shape. When a sinusoidal tensile load γ = γ₀sinωt is applied, the vibration σ of the substance 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. Furthermore, a viscoelastic material exhibits behavior intermediate between that of an elastic and a viscous body. That is, the viscoelastic material can dampen the energy resulting from vibrations.

[0019] The energy loss G per period of the vibration-like deformation of the viscoelastic material is expressed as G = (σ0 / γ0) × sinδ, and the loss factor is expressed as tanδ (where 0 < δ < π / 2). A larger loss factor is preferred. If a viscoelastic material other than those listed above is used as a component of the vibration absorption element 2, such as rubber, gel, or an elastomer, a material with a loss factor of 0.2 or greater is suitable.

[0020] The thickness of the vibration absorption element 2 can be selected taking into account both its heat dissipation properties and its insulation reliability. The vibration-damping properties of the vibration absorption element 2 can be further improved by using a vibration-damping gel and a vibration-damping rubber. Specific examples of vibration-damping rubber include acrylic rubber, silicone rubber, and fluororubber, which have excellent thermal resistance, as well as butyl rubber, which has high damping properties, and butadiene rubber, which has a low dynamic-to-static stiffness ratio. A specific example of vibration-damping gel is silicone gel.

[0021] Fig. Figure 4 shows a calculation example of the maximum electric field strength when the thickness of the vibration absorption element 2 and the thickness of the thermally conductive insulating element 16 are equal, and Fig. Figure 5 shows a calculation example of the maximum electric field strength when the thickness of the vibration absorption element 2 is twice the thickness of the thermally conductive insulating element 16, for each of the cases with and without bubbles.

[0022] "Bubbles" refers to those bubbles that are generated within the vibration absorption element 2. The numerical values ​​on the vertical axes in Fig. 4 and Fig. 5 are the ratios to the maximum electric field strength in the case where there is no vibration absorption element 2, which is referred to as the "standard". ε s denotes the relative permittivity or relative dielectric constant of the vibration absorption element 2, and ε mdenotes the relative permittivity or relative dielectric constant of the thermally conductive insulating element 16.

[0023] If ε s ≤ 3ε m The effect of electric field relaxation is significant, with the ratio of the maximum electric field strength being 0.8 or less compared to the case without the vibration absorption element 2. It is understood that the thicker the vibration absorption element 2, the lower the maximum electric field strength. Furthermore, since the vibration absorption element 2 is in direct contact with the semiconductor device 100, which is a heat source, it must maintain its function even when exposed to high temperatures for extended periods, equivalent to the product's lifetime.

[0024] If a power supply exceeding the thermal resistance of the vibration absorption element 2 is used, problems will occur in the vibration absorption element 2, such as a reduction in thickness due to sol formation or liquefaction, component elution, and reduced insulation reliability due to chemical reactions with other components, which significantly impairs its function as a vibration absorber. Therefore, a material with a temperature margin of 10 °C or more up to a change point in physical properties, such as the glass transition temperature or the sol formation temperature, is suitable for the vibration absorption element 2.

[0025] If the vibration absorption element 2 is used with a semiconductor device 100 that does not have the thermally conductive insulating element 16, the vibration absorption element 2 must also take over the function of the thermally conductive insulating element 16. Therefore, a viscoelastic material with a specific volume resistance of 10 is used. 10 Ω· or more and a relative dielectric constant of 20 or less within the operating temperature range of the power device 1000 is used as a component material of the vibration absorption element 2. The component material of the vibration absorption element 2 can be selected as described above, and the thickness of the vibration absorption element 2 and the like can be selected or designed. As an example of the design, the thickness d s of the vibration absorption element 2 and the thickness d mof the thermally conductive insulating element 16 are chosen such that they satisfy the relation d s ≥ d m have.

[0026] As in Fig. As shown in Figure 3, the semiconductor device 100 comprises at least one semiconductor chip 11, and the interior and exterior of the semiconductor device 100 are electrically connected by means of the conductor frame 12. Since various components of the semiconductor device 100, different from those above, are present depending on the intended use, they can be appropriately provided.

[0027] Examples of the semiconductor chip 11, which is arranged in the semiconductor device 100, include semiconductor elements for high-current control, such as an insulated gate transistor (IGBT), a metal oxide semiconductor field-effect transistor (MOSFET), and a diode.

[0028] Silicon (Si) is usually used as a semiconductor material to form the semiconductor chip 11. Alternatively, the semiconductor chip 11 can be made from a wide-bandgap semiconductor material, such as silicon carbide (SiC), gallium nitride (GaN), and diamond (C), which are used as semiconductor materials to form high-power semiconductor chips.

[0029] The semiconductor chip 11, which uses a wide-bandgap semiconductor as a component material, has lower power losses and can be operated at higher temperatures than the semiconductor chip 11, which uses Si as a component material, so that miniaturization of the semiconductor device 100 itself and miniaturization of the power device 1000 in which the semiconductor device 100 is mounted can be achieved. Although Fig. Figure 3 illustrates an example in which a single semiconductor chip 11 is mounted in the power unit 1000; it is also possible to mount a plurality of semiconductor chips 11 in a single power unit 1000, as described later.

[0030] The conductor frame 12 is a component responsible for the electrical connection between the interior and exterior (between inside and outside) of the semiconductor device 100. For this reason, a metal with high electrical conductivity, such as gold, copper, or aluminum, or an alloy of these metals, is suitable as the material for the conductor frame 12. In the example of the semiconductor device 100, which is in Fig. As shown in Figure 3, the conductor frame 12 projects outwards from a side surface region of the semiconductor device 100 and has an L-shape. However, unlike this example, the function as a conductor frame 12 can also be achieved if the conductor frame 12 projects upwards from the upper surface of the semiconductor device 100. Furthermore, the function as a conductor frame 12 can even be achieved with a linear shape or other shapes.

[0031] The heat distributor 13 is a component for dissipating heat generated by the semiconductor chip 11 to the outside of the semiconductor device 100. A metal with high thermal conductivity, such as copper or aluminum, is suitable as a component material for the heat distributor 13.

[0032] The heat distributor 13 can also be formed using an alloy of these metals. Although the heat distributor 13 and the ladder frame 12 in Fig. Even if three things are independent, they can also have an integrated structure.

[0033] The sealing element 14 insulates between the inside and outside of the semiconductor device 100 by covering the entire assembly consisting of the semiconductor chip 11, the heat spreader 13, the wire 15, and part of the conductor frame 12. Since the insulating reliability of the sealing element 14 deteriorates due to factors such as delamination, blistering, and the introduction of foreign materials, it is desirable that the semiconductor device 100 be manufactured, for example, by transfer molding or injection molding using a mold.

[0034] The sealing element 14 may consist of a resin with excellent insulating properties, such as epoxy resin, polyimide, polyamide, or polyamide-imide, or a mixture prepared by adding silicon dioxide, aluminum oxide, aluminum nitride, or boron nitride to one of these resins. It is sufficient if these materials have a specific volume resistance of 10 10 Ω‧cm or higher and have a relative permittivity of 20 or less within the operating temperature range of the power device 1000. Suitable examples include gases such as SF6 or nitrogen, or materials other than those listed above.

[0035] The wire 15 electrically connects the semiconductor chip 11 and the conductor frame 12. A metal with high electrical conductivity, such as gold, copper, or aluminum, or an alloy of a metal with high electrical conductivity, is suitable as the component material for the wire 15. However, the conductor frame 12 can also be bonded directly to the semiconductor chip 11 without using the wire 15.

[0036] Wire 15 can also be connected as a signal line for controlling the power of the semiconductor chip 11. When wire 15 is used as a signal line, it plays a role in transmitting a control signal from outside the semiconductor device 100 to the semiconductor chip 11 via a control terminal (not shown) and wire 15. Although Fig. Figure 3 shows that the conductor frame 12 is bonded directly to the heat distributor 13; the electrical connection between the heat distributor 13 and the conductor frame 12 can also be made via the wire 15.

[0037] The thermally conductive insulating element 16 is thermally bonded to the heat distributor 13. The thermally conductive insulating element 16 is a component for insulating between the inside and outside of the semiconductor device 100, while conducting the heat generated in the semiconductor device 100. A resin insulating sheet or a thin ceramic plate is used as the thermally conductive insulating element 16. If the thermally conductive insulating element 16 is a resin sheet, then the material used is a resin with excellent insulating properties, such as epoxy resin, polyimide, polyamide, or polyamide-imide, or a mixture prepared by adding silicon dioxide, aluminum oxide, aluminum nitride, or boron nitride to one of these resins.

[0038] When a thin ceramic plate is used as a thermally conductive insulating element 16, a ceramic with excellent insulating and heat dissipation properties, such as silicon dioxide, aluminum oxide, aluminum nitride, or silicon nitride, is used. To improve the insulating properties of the thermally conductive insulating element 16, a greater thickness is suitable, whereas a reduced thickness is preferred to improve the heat dissipation properties.

[0039] Therefore, the thickness of the thermally conductive insulating element 16 can be chosen to account for the conflicting objectives between the two. The thickness of the thermally conductive insulating element 16 is suitably approximately 20 to 50 µm, and the upper limit of the thickness is approximately 2 mm. By using a material with excellent insulating properties for the thermally conductive insulating element 16, its thickness can be reduced.

[0040] For example, a material with a specific volume resistance of 10 is used as a component material of the thermally conductive insulating element 16. 10 Ω‧cm or higher and a relative dielectric constant of 20 or less are suitable. Method for manufacturing the power unit according to embodiment 1

[0041] Fig. Figure 6 is a flowchart describing a method for manufacturing the power unit according to embodiment 1.

[0042] In step 101, the semiconductor device 100 is manufactured. In step 102, the vibration absorption element 2 is formed on the heat sink 1. In step 103, the semiconductor device 100 is positioned on the vibration absorption element 2.

[0043] In step 104, post-processing operations, such as assembling the housing and bonding the ladder frame, are carried out according to the shape of the power unit 1000.

[0044] The vibration absorption element 2 is formed on the heat sink 1, and then it undergoes degassing and hardening. Alternatively, the vibration absorption element 2 can be formed on the heat sink 1 after it has been shaped into a flat body form. Modification of the method for manufacturing the power unit according to embodiment 1

[0045] Fig. Figure 7 is a flowchart to describe a modification of the method for manufacturing the power unit according to embodiment 1.

[0046] In step 201, the semiconductor device 100 is manufactured. In step 202, the unhardened vibration absorption element 2 is positioned on the heat sink 1. In step 203, the unhardened vibration absorption element 2 is applied to the semiconductor device 100. In step 204, the semiconductor device 100 is positioned on the unhardened vibration absorption element 2 on the heat sink 1. In step 205, the vibration absorption element 2 is degassed and hardened. In step 206, post-processing operations, such as assembling the housing and bonding the conductor frame, are carried out according to the shape of the power device 1000.

[0047] Compared to the method for manufacturing the power device according to embodiment 1, the modified method for manufacturing the power device according to embodiment 1 increases the number of steps and complicates the work, but the possibility of bubbles penetrating the vibration absorption element 2 can be reduced. Although some effect can also be achieved by omitting either step 202 or step 203, it is better to perform both steps, as shown in the flowchart in Fig. 7. Modification 1 of embodiment 1

[0048] Fig. Figure 8 is a top view of a power unit 1100 according to modification 1 of embodiment 1. The power unit 1100 has a plurality of semiconductor devices 100 mounted on a single heat sink 1 via the vibration absorption element 2. The number of semiconductor devices 100 necessary to meet requirements is arranged on the heat sink 1 according to the function or voltage class required for the power unit. In the example shown in Fig. As shown in Figure 8, a total of sixteen semiconductor devices (100) are mounted in a single power unit (1100). Modification 2 of embodiment 1

[0049] Fig. Figure 9 is a side view of a power device 1200 according to modification 2 of embodiment 1. The power device 1200 is configured for use with a double-sided cooler type semiconductor device 200. The configuration of the power device 1200 is such that the vibration-absorbing elements 2 are arranged on both the upper and lower surfaces of the semiconductor device 200, one per surface, and the semiconductor device 200 is sandwiched between the heat sinks 1 from the top and bottom.

[0050] Even if the vibration absorption element 2 is only arranged between one of the two heat sinks 1 and the semiconductor device 100, a certain effect is observed. As in Fig. As shown in Figure 9, however, it is more desirable to arrange the vibration absorption element 2 between each of the two heat sinks 1 and the semiconductor device 200, from the perspective of effectively absorbing external vibrations. Effects of embodiment 1

[0051] As described above, the following applies to the power device and the method for manufacturing a power device according to embodiment 1: By arranging the vibration absorption element between the thermally conductive insulating element of the semiconductor device and the heat sink, the vibration energy acting on the semiconductor device, in particular on the thermally conductive insulating element, can be dampened. This results in a power device that is capable of preventing damage to its components, maintaining long-term insulation reliability, and is also easy to manufacture. Design 2

[0052] Fig. Figure 10 is a side view of a power unit 1300 according to embodiment 2. The power unit 1300, which is in Fig. As shown in Figure 10, a housing 3 has a pressure mechanism that pushes the semiconductor device 100 towards the heat sink 1. A pressure mechanism other than the housing 3 can also be used. For example, a heavy object can be pushed on, or a screw and spring mechanism can be used, as long as it functions as a pressure mechanism.

[0053] The housing 3 is a component for restricting the movement of the semiconductor device 100 caused by vibration. In a configuration where a single power unit has a plurality of semiconductor devices 100, such as the power unit 1100 according to modification 1 of embodiment 1, the pressure mechanism exemplified by the housing 3 plays a role in preventing contact between the semiconductor devices 100 and ensuring insulation reliability. Examples of the component material of the housing 3 include resins with excellent insulating properties, such as epoxy resin, polyimide, polyamide, or polyamide-imide, or mixtures prepared by adding silicon dioxide, aluminum oxide, aluminum nitride, or boron nitride to one of these resins.

[0054] Although Fig. Figure 10 shows an example of a shape where the conductor frame 12 of the semiconductor device 100 projects outside the housing 3. The conductor frame 12 does not necessarily need to penetrate the housing 3. In the case of a shape where the conductor frame 12 projects outside the housing 3, the degree of design freedom is high, for example, for arranging other components on the outside of the housing 3.

[0055] On the other hand, in a configuration where the conductor frame 12 does not penetrate the housing 3, the influence of vibrational energy from the housing 3 can be reduced, but other components must also be arranged within the housing 3, thus reducing the degree of freedom in the design of the semiconductor device 100. Furthermore, if a shape is adopted where the conductor frame 12 protrudes to the outside of the housing 3, the influence of vibrational energy from the housing 3 can be reduced, while the degree of design freedom is ensured by hollowing out a portion of the housing 3 so that the conductor frame 12 and the housing 3 do not come into contact.

[0056] However, if the force that the vibration absorption element 2 presses against the heat sink 1 is too strong from the housing 3, which is the pressure mechanism, the effect of the power device 1300 according to embodiment 2 is reduced, which is not preferred. Modification 1 of embodiment 2

[0057] Fig. Figure 11 is a side view of a power unit 1400 according to modification 1 of embodiment 2. In the power unit 1400, a buffer material 4 is arranged between the semiconductor device 100 and the housing 3 for load relaxation. The power unit 1400 achieves the effect of being able to relax the loads exerted by the housing 3 on the semiconductor device 100 by means of the buffer material 4, while retaining the function of the housing 3 to limit the range of motion of the semiconductor device 100.

[0058] As described above, the buffer material 4 is a component that relaxes the loads pressing the semiconductor device 100 against the heat sink 1 through the housing 3, while maintaining the housing 3's function of limiting the movement range of the semiconductor device 100. An example of a component material for the buffer material 4 is foam.

[0059] Specific examples of the foam include mixtures prepared by adding a foaming agent, such as N,N'-dinitrosopenta-methylenetetramine, to a resin, such as urethane, polyethylene, natural rubber, or silicone rubber. Since the buffer material 4 comes into contact with the semiconductor device 100, which generates a great deal of heat, it is preferable, in the case of the above component materials, to use a resin with excellent thermal resistance, such as silicone rubber, as the base material.

[0060] Providing the surface of the buffer material 4 with adhesive properties is even better, as this can reduce the positional displacement of the buffer material 4 due to vibrations. Modification 2 of embodiment 2

[0061] Fig. Figure 12 is a side view of a power unit 1500 according to modification 2 of embodiment 2. In the power unit 1500, the vibration absorption element 2 is arranged between the semiconductor device 100 and the housing 3 for load relaxation. The power unit 1500 can relax the loads that are transferred from the housing 3 to the semiconductor device 100 through the vibration absorption element 2, while the function of the housing 3 to limit the range of motion of the semiconductor device 100 is retained. Effects of embodiment 2

[0062] As described above, according to the power unit of embodiment 2, the movement of the semiconductor device can be restricted by the pressure mechanism that presses the semiconductor device against the vibration-absorbing element. This prevents damage to the components, thus maintaining the long-term insulation reliability of the power unit. embodiment 3

[0063] Fig. Figure 13 is a side view of a power unit 1600 according to embodiment 3. The following applies to the power unit 1600: By forming a recess 1a in the heat sink 1, the positioning accuracy during manufacturing is improved. That is, the semiconductor device 100 is positioned by such a positioning of its base area that it corresponds to the recess 1a on the side of the heat sink. Consequently, the positioning accuracy of the semiconductor device 100 with respect to the heat sink 1 is improved. Modification 1 of embodiment 3

[0064] Fig. Figure 14 is a side view of a power unit 1700 according to modification 1 of embodiment 3. In the power unit 1700, the vibration absorption element 2 is arranged only in a recess 1b of the heat sink 1. By adopting such a configuration, the amount of material used to form the vibration absorption element 2 can be reduced. Consequently, the manufacturing costs of the power unit 1700 are reduced. Effects of embodiment 3

[0065] As described above, in the power unit of embodiment 3, the recess is arranged in the heat sink, and the semiconductor device is arranged by positioning its base area so that it corresponds to the recess on the side of the heat sink. This results in a simple power unit capable of maintaining long-term insulation reliability. Design 4

[0066] Fig. 15 and Fig. Figures 16 and 16 are a side view and a top view of a power device 1800 according to embodiment 4. In the power device 1800, a leg area 5 is arranged such that it fills the space between the conductor frame 12 of the semiconductor device 100 and the vibration absorption element 2, so that the vibration energy exerted on the conductor frame 12 is reduced.

[0067] The leg section 5 is arranged such that one end is in contact with a base surface of the conductor frame 12 and the other end is in contact with a surface of the vibration absorption element 2. The leg sections 5 can be arranged on all conductor frames 12 of the semiconductor device 100, or the leg sections 5 can be arranged on only some of the conductor frames 12.

[0068] The conductor frame 12 of the semiconductor device 100 bends as a result of vibration and is temporarily deformed. The degree of deformation is proportional to the length of the conductor frame 12, and detachment or flaking can occur within the semiconductor device 100 as a result of the bending. "Vibration energy" refers to the energy generated when the conductor frame 12 vibrates due to external vibrations. In the power device 1800 according to embodiment 4, the following applies: By arranging the leg section 5 between the conductor frame 12 and the vibration absorption element 2, it is possible to absorb the vibration energy acting on the conductor frame 12.

[0069] When the semiconductor device 200 of the double-sided cooling type of the power device 1200 is mounted according to modification 2 of embodiment 1, as shown in Fig.As shown in Figure 9, the conductor frame 12 of the semiconductor device 200 is long to facilitate wiring. Therefore, it bends significantly, even with small vibrational energy, and detachment or flaking can occur within the semiconductor device 200. In the power device 1800 according to embodiment 4, the following applies: By arranging the leg section 5 between the conductor frame 12 and the vibration absorption element 2, it becomes possible to absorb the vibrational energy acting on the conductor frame 12.

[0070] Leg section 5 is a component that holds or supports the conductor frame 12. As described above, it is located between the conductor frame 12 and the vibration-absorbing element 2. Examples of component materials for leg section 5 include resins with excellent insulating properties, such as epoxy resin, polyimide, polyamide, or polyamide-imide, or mixtures prepared by adding silicon dioxide, aluminum oxide, aluminum nitride, or boron nitride to one of these resins.

[0071] To reduce the weight of the power device, the function of leg area 5 is also evident when using a mixture produced by adding a foaming agent to a resin, such as urethane, polyethylene, natural rubber or silicone rubber, which is the same material as the foam that is an example of the sealing element 14. Effects of embodiment 4

[0072] As described above, the following applies to the power unit of embodiment 4: Since the leg area is arranged between the conductor frame and the vibration absorption element, it is possible to absorb the vibration energy acting on the conductor frame. This results in a power unit with even better long-term insulation reliability.

[0073] Although various exemplary embodiments and examples of the present invention are described, the various features, aspects and functions described in relation to one or more embodiments are not limited to application in any particular embodiment and can be applied to any embodiment alone or in various combinations thereof.

[0074] Consequently, countless variations not shown are included within the scope of the technology in the present invention. For example, this includes cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with a component in another embodiment. Description of the reference symbols 1 heat sink 1a, 1b recess 2 Vibration absorption element 3 cases 4 Buffer material 5 Thigh area 11 Semiconductor chip 12 ladder frames 13 heat spreaders 14 Sealing element 15 wires 16 thermally conductive insulating element 100, 200 semiconductor equipment 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800 Performance equipment QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 5 383 599 B2

[0004]

Claims

Power device comprising: a heat sink; a vibration absorption element arranged on the heat sink for absorbing vibrations; and a semiconductor device arranged on the vibration absorption element. Power device according to claim 1, wherein the semiconductor device has a thermally conductive insulating element arranged on a bottom surface side, and the thermally conductive insulating element is arranged on the heat sink above the vibration absorption element. Power device according to claim 1 or 2, wherein the vibration absorption element is formed from a viscoelastic material. Performance device according to claim 3, wherein the viscoelastic material is any of a gel, a rubber or an elastomer. Performance device according to claim 4, wherein the gel is any of a silicone gel, a urethral gel or a polyacrylamide gel. Power device according to claim 1 or 2, wherein the vibration absorption element is a vibration-damping gel or a vibration-damping rubber. Power device according to one of claims 1 to 6, wherein the loss factor of the vibration of the vibration absorption element is 0.2 or more. Power device according to any one of claims 1 to 7, wherein the vibration absorption element has a specific volume resistance of 1010Ω·cm or more and a relative dielectric constant of 20 or less. Power device according to claim 2, wherein the relative dielectric constant εs of the vibration absorption element and the relative dielectric constant εm of the thermally conductive insulating element have the relation εs≤ 3εm. Power device according to claim 2 or 9, wherein the thickness ds of the vibration absorption element and the thickness dm of the thermally conductive insulating element have the relation ds≥ dm. Power device according to one of claims 1 to 10, which further comprises a pressure mechanism for pressing the semiconductor device and the vibration absorption element against the heat sink. Power device according to claim 11, wherein a buffer material is arranged between the semiconductor device and the printing mechanism. Power device according to one of claims 1 to 12, wherein a recess with a base area larger than the base area of ​​the semiconductor device is formed in a surface of the heat sink which faces the base area of ​​the semiconductor device. Power device according to claim 13, wherein the vibration absorption element is arranged only within the recess. Power device according to one of claims 1 to 14, wherein the semiconductor device has a conductor frame projecting from a side surface area, and a leg area is arranged between the conductor frame and the heat sink, wherein one end of the leg area is in contact with the conductor frame and the other end of the leg area is in contact with the heat sink. Method for manufacturing a power device, the method comprising: a step for forming a vibration absorption element on a heat sink; and a step for forming the vibration absorption element on a bottom surface - opposite the heat sink - of a semiconductor device. A method for manufacturing a power device, the method comprising: a step for forming a vibration absorption element on a heat sink; and a step for arranging a semiconductor device on the vibration absorption element. Method for manufacturing the power device according to claim 16, further comprising a step for degassing and hardening the vibration absorption element, wherein the step for forming the vibration absorption element on the heat sink comprises applying the vibration absorption element, which is unhardened, to the heat sink, and the step for forming the vibration absorption element on the semiconductor device comprises applying the vibration absorption element to the semiconductor device and then arranging the semiconductor device on the heat sink.

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