Heat dissipation substrate for power semiconductor module, power semiconductor module including the same, and power conversion apparatus

Abstract

To provide a heat dissipation substrate for power semiconductor modules, a power semiconductor module including the same, a power conversion apparatus including the same, and a method for manufacturing the same, in which the heat dissipation performance of a working fluid vapor chamber heat spreader does not deteriorate, and separation or warping at the bonding interface due to the difference in thermal expansion coefficients between the heat substrate and the heat dissipation component does not occur.SOLUTION: In a power semiconductor module 500, a heat dissipation substrate 400 for power semiconductor modules includes an insulating substrate 410, lower metal plates 421, 422 positioned under the insulating substrate, and an upper metal plate 423 positioned on the insulating substrate, and the lower metal plate includes a hollow structure HE. The lower metal plate and the upper metal plate contain the same metal material. The heat dissipation substrate for power semiconductor modules is formed by stacking the lower metal plate, the insulating substrate, and the upper metal plate, then bonding them directly without an adhesive layer through a hot press process.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The embodiments relate to a heat dissipation substrate for a power semiconductor module, a power semiconductor module and a power conversion device including the same, and a method for manufacturing a heat dissipation substrate for a power semiconductor module.

[0002] The embodiment also relates to a technology relating to heat dissipation parts for semiconductor elements and the like. [Background technology]

[0003] Power conversion modules are used in a variety of electrical and electronic devices, including eco-friendly vehicles such as electric vehicles (EVs) and fuel cell vehicles (PCEVs), as well as electric vehicle chargers, energy storage devices, power supply devices, and railways, and perform functions such as power conversion (DC⇔AC), motor drive switching, and power control.

[0004] A power conversion module includes various components such as power semiconductor devices, heat dissipation substrates, base plates, molding silicon, cases, and terminals. However, heat generated by the power semiconductor devices generates thermo-mechanical stress in each component of the power semiconductor module, which reduces the lifespan of the power semiconductor devices due to thermal fatigue at the junctions. Therefore, it is important to design a reliable power semiconductor module that dissipates the heat generated by the power semiconductor devices through the heat dissipation substrate and maintains the temperature of the junctions of the power semiconductor devices below an appropriate temperature.

[0005] Conventional heat dissipation substrates for power semiconductors can be categorized into DBC (Direct Bonded Copper) and AMB (Active Metal Brazing) methods depending on the bonding method. The DBC method involves forming an oxide film on the copper (Cu) layer and then directly bonding it to the ceramic, while the AMB method involves brazing by inserting a paste containing metal particles with a low melting point as an intermediate material between the base metal and ceramic.

[0006] Recently, 1200V, 200A class high voltage / high power SiC power conversion modules are being used to improve the performance of hybrid and electric vehicles and for autonomous driving vehicles. The operating temperature of power semiconductor devices in such high performance electric vehicles must be above 300℃ on average while in operation, and they are facing ultra-high temperature usage conditions with momentary maximum operating temperatures of 350℃~700℃.

[0007] In such an ultra-high temperature, high voltage, and high current operating environment, existing bonding materials themselves re-melt, and pores in the bonding areas cause heat trapping, rapidly shortening the lifespan of power semiconductor modules and inducing thermal runaway, which can lead to the destruction of power semiconductor elements and seriously affect the safety of drivers.

[0008] In the prior art, various heat dissipation components and heat dissipation modules such as heat sinks, heat dissipation plates, heat pipes, vapor chambers, etc. have been adopted to solve the heat generation problem of electronic devices such as power semiconductor modules.

[0009] For example, prior patent 1US2020 / 0132392A1 (2020.04.30) is an invention relating to a "vapor chamber heat spreader for power electronic assemblies" (see patent documents in the prior art documents below).

[0010] FIG. 1a is a diagram of FIG. 2 of the power electronic assembly 10 of Prior Patent 1. FIG.

[0011] In Prior Patent 1, each component of the power electronic assembly 10 is bonded together by a bonding layer 50. Specifically, the upper and lower sides of the electronic element 20 in Prior Patent 1 are bonded to the substrate 21 and the spacer layer 70, respectively, by the bonding layer 50. The upper side of the spacer layer 70 is also bonded to the auxiliary substrate 21A by the bonding layer 50. In Prior Patent 1, the substrate 21 and the auxiliary substrate 21A are DBC (Direct Bonded Copper) heat dissipation substrates, in which a copper layer is directly bonded to the surface of a ceramic insulating substrate. Prior Patent 1 also includes a wire 68 that electrically connects the gate electrode 66 and the electronic element 20.

[0012] Meanwhile, in Prior Art Patent 1, the substrate 21, electronic element 20, spacer layer 70, auxiliary substrate 21A, wiring 68, and gate electrode 66, which are bonded with adhesive layer 50, are packaged with resin 69. After packaging, a separately manufactured vapor chamber heat spreader 102 is bonded to the cooling surface 24 of the substrate 21 and the cooling surface 24A of the auxiliary substrate 21A with adhesive layers 80 containing thermal grease or a non-conductive material, respectively, to perform heat dissipation. The vapor chamber heat spreader 102 includes an evaporation plate 104, a condensation plate 106, sidewalls 108, a vapor chamber 110, a thermal compensation layer 130, and pins 126, and the thermal compensation layer 130 contains core-shell phase change particles to increase heat capacity.

[0013] The vapor chamber heat spreader 102 of Prior Patent 1 includes a working fluid disposed in the vapor chamber 110. The working fluid is a fluid having a vaporization temperature within the operating temperature range of the vapor chamber. The working fluid evaporates on the evaporating surface of the evaporator plate 104 and condenses on the condensing surface of the condenser plate 106. The condensed working fluid is transported by capillary action along the condenser plate 106 and sidewall 108 and / or pins 126 to the evaporator plate 104, where it is re-evaporated and vaporized at the hot spots on the evaporator plate 104.

[0014] However, when a separately manufactured vapor chamber heat spreader 102 is bonded to the substrate 21 or auxiliary substrate 21A with adhesive 80 as in prior art 1, not only does the heat transfer path from the heat source electronic element 20 to the vapor chamber heat spreader 102 become longer, but the presence of a separate adhesive layer between the vapor chamber heat spreader 102 and the substrate 21 or auxiliary substrate 21A creates thermal resistance and reduces heat transfer efficiency, resulting in problems such as normal vaporization of the working fluid and reduced heat dissipation performance.

[0015] Furthermore, as in prior art 1, when a separately manufactured vapor chamber heat spreader 102 is bonded to the substrate 21 or auxiliary substrate 21A with adhesive 80, there is a problem that separation of the bonding interface or warping of the components occurs due to the difference in thermal expansion coefficient between the bonded substrate 21 or auxiliary substrate 21A.

[0016] For example, FIG. 1b is a photograph showing warpage WP after the AMB heatspreader according to the comparative technology is bonded to the base plate BP.

[0017] In the heat dissipation substrate manufactured using the comparative AMB technology, there is a significant difference in the coefficient of thermal expansion (CTE) of the insulating substrate SS, upper copper plate T-Cu, lower copper plate B-Cu, SiC chip, and base plate BP. For example, the coefficient of thermal expansion of the AlN insulating substrate SS is 4.5 x 10 -6 / °C, and the thermal expansion coefficient of the upper and lower copper (T-Cu, B-Cu) is 16.0×10 -6 / °C, and the thermal expansion coefficient of the SiC chip is 4.0 x 10 -6 / ℃. However, in an ultra-high temperature operating environment of 300℃ or more, differences in the thermal expansion coefficients of the components that make up the power semiconductor module can cause warpage WP as shown in Figure 1b or separation between the interfaces, which can lead to malfunction of the power semiconductor module.

[0018] Therefore, when a separately manufactured vapor chamber heat spreader 102 is bonded to the heat dissipation substrate 21 or auxiliary heat dissipation substrate 21A with adhesive 80, as in the aforementioned Prior Patent 1, the difference in the thermal expansion coefficients of the materials of the bonded components can cause separation at the bonding interface or warping of the components, impairing the heat dissipation function of the vapor chamber heat spreader 102. This can lead to rapid deterioration of the power semiconductor module, inducing thermal runaway and leading to the destruction of the power semiconductor elements, which can have a serious impact on the safety of the driver. [Prior art documents] [Patent documents]

[0019] US Published Patent Number (Publication Date): US2020 / 0132392A1 (2020.04.30) Summary of the Invention [Problem to be solved by the invention]

[0020] One of the technical challenges of the embodiment is to solve the problem that when the vapor chamber heat spreader is bonded to the heat dissipation substrate with an adhesive, not only does the heat transfer path from the electronic element, which is the heat source, to the vapor chamber heat spreader become longer, but also the presence of an additional adhesive layer between the vapor chamber heat spreader and the heat dissipation substrate creates thermal resistance, reducing the heat transfer efficiency and reducing the heat dissipation performance of the working fluid vapor chamber heat spreader.

[0021] In addition, one of the technical objectives of the embodiment is to solve the problem that when a heat dissipation substrate and a heat dissipation component are bonded with an adhesive layer, the difference in the thermal expansion coefficients of the bonded components causes separation of the bonding interface or warping of the components, resulting in malfunction of the power semiconductor module.

[0022] The technical problems of the embodiments are not limited to those described in this section, but include those that can be understood from the description of the invention. [Means for solving the problem]

[0023] The heat dissipation substrate for a power semiconductor module according to the embodiment includes an insulating substrate 410, lower metal plates 421 and 422 arranged under the insulating substrate 410, and an upper metal plate 423 arranged on the insulating substrate 410, and the lower metal plates 421 and 422 may include a hollow structure HE.

[0024] The lower metal plates 421 and 422 may include a second metal plate 422 bonded to the bottom surface of the insulating substrate 410 and a first metal plate 421 bonded to the bottom surface of the second metal plate 422 .

[0025] The second metal plate 422 may include a 2-1 metal plate 422a having a plurality of first through trenches E1 arranged in a first direction X and bonded to the insulating substrate 410, and a 2-2 metal plate 422b having a plurality of second through trenches E2 arranged in a second direction Y perpendicular to the first direction X and bonded to the bottom surface of the 2-1 metal plate 422a.

[0026] The first through trench E1 and the second through trench E2 may be three-dimensionally connected to form the hollow structure HE.

[0027] The 2-1 metal plate 422a may include a first body B1 between a plurality of spaced apart first through-trenches E1, and the 2-2 metal plate 422b may include a second body B2 between a plurality of spaced apart second through-trenches E2.

[0028] The thickness T3 of the third metal plate 423 may be greater than the thickness of the first metal plate 421 or the thickness of the second metal plate.

[0029] The third metal plate may include a circuit pattern on its surface.

[0030] The first metal plate, the second metal plate, and the third metal plate may include the same metal material.

[0031] The second metal plate may be directly bonded to the bottom surface of the insulating substrate without an adhesive layer, and the first metal plate may be directly bonded to the bottom surface of the second metal plate without an adhesive layer.

[0032] The power semiconductor module according to the embodiment may include any one of the heat dissipation substrates for a power semiconductor module and a power semiconductor element disposed on the upper metal plate 423 .

[0033] A method for manufacturing a heat dissipation substrate for a power semiconductor module according to an embodiment may include the steps of preparing an insulating substrate, preparing a first metal plate, a second metal plate, and a third metal plate, sequentially stacking the first metal plate and the second metal plate, stacking the insulating substrate on the second metal plate, stacking the third metal plate on the insulating substrate to prepare a substrate stack set, and performing a hot pressing process on the stacked substrate stack set.

[0034] The second metal plate 422 may include a 2-1 metal plate 422a having a plurality of first through trenches E1 arranged in a first direction X, and a 2-2 metal plate 422b having a plurality of second through trenches E2 arranged in a second direction Y perpendicular to the first direction X.

[0035] The first through trench E1 and the second through trench E2 are three-dimensionally connected by the pressing process, thereby forming the hollow structure HE.

[0036] The 2-1 metal plate 422a may include a first body B1 between a plurality of spaced apart first through-trenches E1, and the 2-2 metal plate 422b may include a second body B2 between a plurality of spaced apart second through-trenches E2.

[0037] The second metal plate may be directly bonded to the bottom surface of the insulating substrate without an adhesive layer, and the first metal plate may be directly bonded to the bottom surface of the second metal plate without an adhesive layer. [Effects of the Invention]

[0038] One of the technical effects of the embodiment is that when the vapor chamber heat spreader is bonded to the heat dissipation substrate with an adhesive, the problem of reduced heat transfer efficiency resulting in reduced heat dissipation performance of the working fluid vapor chamber heat spreader can be solved.

[0039] For example, according to the embodiment, a hot press process is performed in a high-temperature, high-pressure, vacuum environment, so that a heat dissipation substrate can be realized that is integrally provided with a metal plate having a hollow structure HE that can be filled with a working fluid. As a result, according to the embodiment, the heat transfer path between the power semiconductor device, which is a heat source, and the metal plate having the hollow structure HE is significantly shortened, improving heat transfer efficiency, and thereby efficiently evaporating the working fluid, resulting in a technical effect of significantly improving heat dissipation performance.

[0040] In addition, according to the embodiment, a heat dissipation substrate is realized that is integral with a metal plate having a hollow structure HE that can seal a working fluid in the heat dissipation substrate itself. This reduces thermal resistance by eliminating the need for a separate adhesive layer, thereby improving heat transfer efficiency and significantly improving heat dissipation performance.

[0041] In addition, one of the technical effects of the embodiment is that when a heat dissipation substrate and a heat dissipation component are bonded together by an adhesive layer, the problem of separation of the bonding interface or warping of the components due to differences in the thermal expansion coefficients of the bonded components, which results in malfunction of the power semiconductor module, can be solved.

[0042] Specifically, according to the embodiment, a hot press process is performed in a high temperature and high pressure vacuum environment, which has the technical effect of enabling a metal plate having a hollow structure HE that can seal a working fluid in the heat dissipation substrate itself to be formed integrally with the heat dissipation substrate 400.

[0043] For example, referring to FIG. 2, in the heat dissipation substrate 400 according to the embodiment, not only is the interface between the second metal plate 422 having a hollow structure HE and the first metal plate 421 integrally bonded thereto not substantially separated, but also the material of the second metal plate 422 having a hollow structure HE is the same as the material of the first metal plate 421 integrally formed thereto, thereby eliminating the difference in thermal expansion coefficients between the two sides, fundamentally preventing separation of the bonding interface or warpage of the components, and resulting in a special technical effect of significantly improving the reliability of the power semiconductor module.

[0044] In addition, one of the technical effects of the embodiment is that the hot pressing process is performed while maintaining the alignment of the corners of the first spacer, the second metal plate, the insulating substrate, and the third metal plate, which are sequentially stacked in the manufacturing process of the heat dissipation substrate 400, resulting in a special technical effect of realizing a high-quality heat dissipation substrate having an integrated hollow structure HE.

[0045] The technical effects of the embodiments are not limited to those described in this section, but include those that can be understood from the description of the invention. [Brief explanation of the drawings]

[0046] [Figure 1a] FIG. 1a is a drawing of FIG. 2 relating to the power electronic assembly 10 of Prior Patent 1. FIG. [Figure 1b] Figure 1b shows a photograph of warpage WP occurring after the AMB heatspreader according to the comparative technology was bonded to the base plate BP. [Figure 2] FIG. 2 is a cross-sectional view of a power semiconductor module 500 including a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 3]FIG. 3 is a cross-sectional view of a power semiconductor element 100 arranged on a power semiconductor module according to an embodiment. [Figure 4] FIG. 4 is a flowchart of a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 5] 5 to 10 are cross-sectional views showing steps in the manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 6] 6A to 6C are cross-sectional views of steps in a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 7a] FIG. 7A is a cross-sectional view of a process for manufacturing a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 7b] FIG. 7B is a cross-sectional view of a process for manufacturing a heat dissipation substrate for a power semiconductor according to the embodiment. [Figure 8] 8A to 8C are cross-sectional views of steps in a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 9] 9A to 9C are cross-sectional views of steps in a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 10] 10A to 10C are cross-sectional views of a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 11a] FIG. 11a is a first cross-sectional view of a power semiconductor module 500 including a heat dissipation substrate for a power semiconductor according to an embodiment. [Figure 11b] FIG. 11b is a cross-sectional view of a power semiconductor module 502 including a heat dissipation substrate for a power semiconductor according to the second embodiment. [Figure 12] FIG. 12 is a second cross-sectional view of the power semiconductor module 500 including the heat dissipation substrate for a power semiconductor according to the embodiment. [Figure 13] FIG. 13 is a diagram showing a heat dissipation component 550 according to an embodiment disposed on a semiconductor device chip on a circuit board 610. In FIG. [Figure 14] FIG. 14 is a circuit diagram illustrating a power conversion device 1000 to which a power semiconductor module according to an embodiment is applied. DETAILED DESCRIPTION OF THE INVENTION

[0047] Hereinafter, the invention according to the embodiment for solving the above problems will be described in more detail with reference to the drawings.

[0048] The power semiconductor module according to the embodiment can be used in inverters and converters for automobiles, computers, home appliances, solar power, smart grids, etc. In addition to eco-friendly automobiles, the power semiconductor module according to the embodiment can be applied to various electric and electronic devices such as electric vehicle chargers, power supply devices, and railways.

[0049] <Power semiconductor module including heat dissipation substrate> FIG. 2 is a cross-sectional view of a power semiconductor module 500 including a heat dissipation substrate for a power semiconductor according to the embodiment, and FIG. 3 is a cross-sectional view of a power semiconductor element 100 disposed on the power semiconductor module according to the embodiment.

[0050] Referring to FIG. 2, a power semiconductor module 500 according to the embodiment may include a heat dissipation substrate 400, a power semiconductor device 100, and a wiring 130a.

[0051] For example, a power semiconductor module 500 according to the embodiment may include a heat dissipation substrate 400, a power semiconductor device 100 disposed on the heat dissipation substrate 400, and a wiring 130a electrically connected to the power semiconductor device 100. The power semiconductor device 100 may be bonded using a predetermined adhesive member 110, but is not limited thereto.

[0052] 2 illustrates an example in which the hollow structure HE that can be filled with a working fluid is provided in the second metal plate 422. However, the present invention is not limited to this. For example, the hollow structure HE that can be filled with a working fluid may also be formed in the third metal plate 423.

[0053] In an embodiment, the power semiconductor device 100 may be bonded onto the heat dissipation substrate 400 by soldering, sintering bonding, transient liquid phase bonding (TLP bonding), ultrasonic bonding, or the like.

[0054] 3, the power semiconductor device 100 according to the embodiment may include a drain electrode 105, a semiconductor epitaxial layer 120, a source electrode 145s, and a gate electrode 165g. The epitaxial layer 120 may include, but is not limited to, SiC (Silicon Carbide). In the form of a MOSFET, the source electrode 145s or the gate electrode 165g may include an Al-based metal, and the drain electrode 105 may include, but is not limited to, Ti / Ni / Ag metal including a Ti layer, a Ni layer, or an Ag layer, NiV / Ag, or V (vanadium) / Ni / Ag.

[0055] 2, the heat dissipation substrate 400 of the embodiment may include one or more metal plates and an insulating substrate 410. For example, the heat dissipation substrate 400 may include, but is not limited to, a first metal plate 421, a second metal plate 422, an insulating substrate 410, and a third metal plate 423.

[0056] The insulating substrate 410 can electrically insulate the second metal plate 422 from the third metal plate 423. The insulating substrate 410 can include a polycrystalline insulating substrate made of a ceramic material with high thermal conductivity. For example, the insulating substrate 410 can be made of one of AlN or Si3N4, but is not limited thereto, and can also be made of Al2O3, etc. Hereinafter, the insulating substrate 410 will be described as a polycrystalline substrate made of a ceramic material, but is not limited thereto, and can also include a single crystal substrate such as a sapphire substrate.

[0057] The first metal plate 421, the second metal plate 422, and the third metal plate 423 may include, but are not limited to, a Cu-based metal. For example, the first, second, and third metal plates 421, 422, and 423 may include at least one of Al, Ni, Ag, Mg, and Zn.

[0058] The second metal plate 422 has one side in contact with the insulating substrate 410 and the other side capable of dissipating heat. A heat dissipation means such as a heat sink is disposed adjacent to the lower side of the first metal plate 421.

[0059] In an embodiment, the second metal plate 422 may include a single metal plate or multiple metal plates. For example, the second metal plate 422 may include a 2-1 metal plate 422a having a first through-trench E1 and a first body B1. The second metal plate 422 may further include a 2-2 metal plate 422b having a second body B2 and a second through-trench E2 (see FIG. 7a).

[0060] Referring again to FIG. 2, the second metal plate 422 is illustrated as including a second-first metal plate 422a and a second-second metal plate 422b, but is not limited to this and may also include a single second-first metal plate 422a.

[0061] In the second metal plate 422, the first through trench E1 and the second through trench E2 may be three-dimensionally connected to form a hollow structure HE, and the hollow structure HE may be filled with a working fluid (not shown) such as acetone, methanol, ethanol, or ultrapure water.

[0062] The first body B1 and the second body B2 of the second metal plate 422 may have a porous structure that can contain or absorb a working fluid. For example, the first body B1 and the second body B2 of the second metal plate 422 may have a porous structure formed by a sintering process. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have fine grooves on their sidewalls. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have a mesh-shaped porous structure.

[0063] According to the embodiment, heat generated from the power semiconductor device 100 is efficiently transferred to the second metal plate 422 of the heat dissipation substrate, so that the working fluid vaporizes, absorbs the latent heat of vaporization, moves toward the lower first metal plate 421, and condenses into a liquid while releasing the latent heat of vaporization, and the condensed working fluid is absorbed into the porous structure of the second metal plate 422 and moves toward the insulating substrate 410. Meanwhile, in the embodiment, the power semiconductor device 100, which is a heat source, can be disposed below the heat dissipation substrate 400, and the condensed working fluid can be moved by gravity.

[0064] Next, the third metal plate 423 may include a plurality of circuit patterns (not shown) formed by a patterning process such as etching, and the circuit patterns are electrically connected to the power semiconductor device 100. For example, as shown in FIG. 2, one side of the circuit patterns of the third metal plate 423 may be electrically connected to the power semiconductor device 100 via wiring 130a such as a wire. In addition, the other side of the circuit patterns of the third metal plate 423 is connected to an external connection terminal. The external connection terminal may include an input power source, a motor, an inverter controller, etc. If the third metal plate 423 does not undergo a patterning process, the heat dissipation substrate 400 of the embodiment may be used as a heat dissipation component.

[0065] According to the power semiconductor module 500 including the heat dissipation substrate 400 for power semiconductors of the embodiment, a hot press process is performed in a high temperature and high pressure vacuum environment, so that the heat dissipation substrate 400 itself can be realized as a heat dissipation substrate integrally comprising a second metal plate 422 having a hollow structure HE that can seal a working fluid.

[0066] As a result, according to the embodiment, the heat transfer path between the power semiconductor element 100, which is the heat source, and the second metal plate 422 having a hollow structure HE is shortened, improving the heat transfer efficiency and allowing the working fluid to be efficiently vaporized, resulting in a technical effect of significantly improving heat dissipation performance.

[0067] In addition, according to the embodiment, a heat dissipation substrate is provided that is integral with the second metal plate 422 having a hollow structure HE that can encapsulate the working fluid in the heat dissipation substrate 400 itself without the need for a separate adhesive layer, so that heat is transferred to the second metal plate 422 having the hollow structure HE without passing through an adhesive layer that may cause thermal resistance. This results in a technical effect of improving heat transfer efficiency and efficiently evaporating the working fluid, thereby significantly improving heat dissipation performance.

[0068] Furthermore, in the heat dissipation substrate 400 according to the embodiment, not only is there no substantial difference in the interface between the second metal plate 422 having a hollow structure HE and the first metal plate 421 integrally bonded thereto without an adhesive layer, but the material of the second metal plate 422 having a hollow structure HE can be the same as the material of the first metal plate 421 integrally formed thereto. This eliminates the difference in thermal expansion coefficient between the first metal plate 421 and the second metal plate 422, thereby fundamentally preventing separation of the bonding interface or warpage of components, resulting in a special technical effect of significantly improving the reliability of the power semiconductor module.

[0069] The technical features of the "power semiconductor module 500 including a heat dissipation substrate" of the present application will be described in detail below while explaining the "manufacturing process of a heat dissipation substrate for a power semiconductor."

[0070] <Manufacturing process for heat dissipation substrates for power semiconductors> FIG. 4 is a schematic process flow chart of a manufacturing process of a heat dissipation substrate for a power semiconductor according to an embodiment.

[0071] The manufacturing process of the heat dissipation substrate for power semiconductors according to the embodiment can broadly include (1) a pretreatment process of the insulating substrate, (2) a sputtering process, (3) a pretreatment process of the metal plate, (4) a lamination process of the insulating substrate and the metal plate, (5) a hot press process of the insulating substrate and the metal plate, (6) a heat dissipation substrate etching process, (7) a heat dissipation substrate inspection and cutting process, etc. The entire manufacturing process of the heat dissipation substrate for power semiconductors according to the embodiment is controlled by a control unit (not shown) of a central server, which may include a data storage unit (not shown).

[0072] The main manufacturing steps of the heat dissipation substrate for power semiconductors according to the embodiment will be described below with reference to the drawings.

[0073] (1) Pre-treatment process for insulating substrates The pretreatment process for the insulating substrate will be described below with reference to Fig. 5. In this embodiment, the "pretreatment process for the insulating substrate" is performed in a substrate cleaning device (not shown) before the "lamination process" of the insulating substrate and the metal plate.

[0074] The pre-processing process of the insulating substrate may include 1. loading the insulating substrate, 2. marking the unique code UC, 3. cleaning the insulating substrate, 4. measuring the thickness of the insulating substrate, and 5. loading the insulating substrate into a magazine.

[0075] 1. Loading stage of insulating substrate First, as shown in Fig. 5, a predetermined insulating substrate base material SS is prepared and loaded into a substrate cleaning device (not shown). The insulating substrate base material SS may be made of AlN, Si3N4, or Al2O3, but is not limited thereto, and may also include a single crystal substrate such as a sapphire substrate. The surface of the insulating substrate 410 may have irregularities R ranging in size from several micrometers to several hundred micrometers, but is not limited thereto.

[0076] 2. Unique code UC marking process According to the embodiment, a unique code UC is marked on the insulating substrate base material SS loaded into the substrate cleaning device. Thereafter, the unique code UC is read and transmitted to and stored in a data storage unit of a server via wired or wireless communication, and detailed information on the "individual heat dissipation substrate" including the "individual insulating substrate" in subsequent processes is precisely updated and managed.

[0077] The insulating substrate base material SS may include an effective area AA and a dummy area DA. The unique code UC is marked in the dummy area DA of the insulating substrate base material SS. The unique code UC may include, but is not limited to, a DMC (Digital Matrix Code), a QR code, or a barcode. The unique code UC may be marked by, but is not limited to, a laser marking technique.

[0078] In the embodiment, a unique ID such as a serial number may also be marked in the dummy area DA of the insulating substrate base material SS in addition to the unique code UC.

[0079] 3. Insulating substrate cleaning process and 4. Thickness measurement process 5, a CDA (Clean Dried Air) cleaning process CL is performed on the insulating substrate base material SS. In addition, in this embodiment, after cleaning the insulating substrate SS, the thickness at nine points can be measured using a displacement sensor™, but is not limited thereto.

[0080] 5. Insulating substrate loading process The insulating substrate base material is loaded into a predetermined substrate magazine (not shown) and then transferred to a predetermined lamination device. In some embodiments, each substrate magazine may also be marked with a predetermined unique ID or code. This allows the unique ID of the substrate magazine to be read during the lamination process, which is performed after the sputtering process, and the lamination and bonding processes can be precisely controlled according to the order required to manufacture the heat dissipation substrate.

[0081] (2) Sputtering process As described above, insulating substrates are loaded in a substrate magazine and transported to a sputtering device, and then the insulating substrates are individually unloaded and loaded into the sputtering device for sputtering.

[0082] Hereinafter, the "sputtering step on an insulating substrate" of the embodiment will be described with reference to FIG.

[0083] 6, a bonding metal layer 411 of a first thickness is formed on one surface of an insulating substrate base material SS by sputtering. During the sputtering process, the unique code UC and the unique ID area are shielded and protected by the sprayed part PS, so that sputtering can be prevented from occurring in the unique code UC and the unique ID area.

[0084] For example, an insulating substrate base material SS is mounted on an anode electrode plate of a predetermined PVD equipment, and a bonding metal layer 411 containing Ti or TiW is formed to a first thickness of about 2,000 Å to 4,000 Å in an inert atmosphere such as Ar gas.

[0085] Next, a diffusion metal layer 412 is formed by sputtering on the bonding metal layer 411. The diffusion metal layer 412 is formed by sputtering to a thickness greater than the first thickness of the bonding metal layer 411.

[0086] The diffusion metal layer 412 may have a melting point lower than the temperature of a hot pressing process for subsequent bonding. For example, the hot pressing temperature may be in the range of about 900°C to 1100°C, and the diffusion metal layer 412 may be made of a material with a melting point lower than 900°C and excellent diffusion. For example, the diffusion metal layer 412 may be made of one or more of Al, Ag, Au, and Sn, but is not limited thereto.

[0087] Next, the insulating substrate base material SS on one surface of which the diffusion metal layer 412 has been formed is turned over, and then the bonding metal layer 411 and the diffusion metal layer 412 can be formed in sequence on the opposite surface by sputtering.

[0088] According to the embodiment, the first and second bonding metal layers 411 and 421 are thinly formed to reduce thermal resistance, thereby providing a technical effect of improving the heat dissipation performance of the heat dissipation substrate.

[0089] In the embodiment, after sputtering, the thickness of the bonding metal layer 411 and the diffusion metal layer 412 for each individual insulating substrate 410 is measured, and the thickness data for each unique code UC is transmitted to a server for update management. For example, in the embodiment, the thickness of the formed bonding metal layer 411 and the diffusion metal layer 412 can be measured by measuring the surface resistance of the individual insulating substrate 410, but is not limited to this. After the thickness measurement of the bonding metal layer 411 and the diffusion metal layer 412 has been completed, the individual insulating substrate 410 is reloaded into the substrate magazine and transferred to the lamination device.

[0090] (3) Metal plate pretreatment process Hereinafter, a metal plate pretreatment process according to an embodiment will be described with reference to Figures 7a and 7b. The metal plate may include a single metal plate or multiple metal plates. For example, the metal plate may include, but is not limited to, a first metal plate 421, a second metal plate 422, and a third metal plate 423.

[0091] The metal plate may be a metal plate having excellent electrical and thermal conductivity. For example, the metal plate may be a Cu plate or a Cu alloy plate, but is not limited thereto. For example, the metal plate may include one or more of Al, Ni, Ag, Mg, and Zn. The metal plate may also be referred to as a metal substrate. In an embodiment, a predetermined unique ID or unique code may be marked on the first metal plate 421, the second metal plate 422, and the third metal plate 423.

[0092] The pre-treatment process for the metal plate may include a cleaning process and a thickness measurement process for the metal plate.

[0093] The metal plates may be classified into multiple groups according to their thickness. For example, the metal plates may be classified into, but are not limited to, a first metal plate 421, a second metal plate 422, and a third metal plate 423 according to their thickness. The third metal plate 423 may be thicker than the first and second metal plates 421 and 422, but is not limited to this.

[0094] The first metal plate 421 may have a first thickness T1. For example, the first metal plate 421 may have a first thickness T1 of 100 μm to 300 μm.

[0095] Also, the second metal plate 422 may include a second-first metal plate 422a having a second-first thickness T2a and a second-second metal plate 422b having a second-second thickness T2b.

[0096] For example, the second-1 metal plate 422a may have a second-1 thickness T2a of 100 μm to 300 μm, and the second-2 metal plate 422b may have a second-2 thickness T2b of 100 μm to 300 μm.

[0097] The 2-1 metal plate 422a may include a plurality of first through trenches E1 arranged in a first direction X. The 2-2 metal plate 422b may include a plurality of second through trenches E2 arranged in a second direction Y perpendicular to the first direction X. Subsequently, in a hot pressing process, the first through trenches E1 and the second through trenches E2 may be three-dimensionally connected to form a hollow structure HE.

[0098] The 2-1 metal plate 422a may include a first body B1 between a plurality of spaced apart first through-trenches E1, and the 2-2 metal plate 422b may include a second body B2 between a plurality of spaced apart second through-trenches E2. The second body B2 of the 2-2 metal plate 422b and the first body B1 of the 2-1 metal plate may have a porous structure capable of generating capillary action.

[0099] For example, the first body B1 of the 2-1 metal plate 422a and the second body B2 of the 2-2 metal plate 422b may have a porous structure that can contain or absorb working fluid. For example, the first body B1 and the second body B2 of the second metal plate 422 may have a porous structure formed by a sintering process. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have fine grooves on their sidewalls. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have a mesh-shaped porous structure. Meanwhile, in an embodiment, the power semiconductor device 100, which is a heat source, may be disposed below the heat dissipation substrate 400, and the condensed working fluid may be moved by gravity.

[0100] In the past, there have been no attempts in the field of heat dissipation substrates to integrally embody a porous structure in the heat dissipation substrate itself, and even in internal research, considerable technical challenges have arisen, such as the occurrence of pore buckling, when forming a porous structure in the heat dissipation substrate itself by hot pressing. However, according to the embodiment, pore buckling can be prevented by forming a porous structure in the second metal plate 422 through a sintering process. Furthermore, according to the embodiment, pore buckling can be prevented by providing groove-shaped grooves on the sidewalls. Furthermore, according to the embodiment, the technical effect of embodying cross-shaped pores is that pore buckling can be prevented during the hot pressing process.

[0101] In addition, according to the embodiment, the porous structure of the second metal plate may be impregnated with a predetermined fluid before the hot pressing process, thereby providing a special technical effect of preventing pore buckling by maintaining the porous structure through the vapor pressure of the fluid.

[0102] 7b, the third metal plate 423 may have a third thickness T3. For example, the third metal plate 423 may have a third thickness T3 of 600 μm to 900 μm.

[0103] In an embodiment, a predetermined unique ID or unique code may be marked on the first metal plate 421, the second-first metal plate 422a, the second-second metal plate 422b, and the third metal plate 423. In this case, the metal plates having the respective thicknesses or through-trenches are loaded into the first metal magazine, the second-first metal magazine, the second-second metal magazine, and the third metal magazine, respectively, and then transferred to a predetermined stacking device. In an embodiment, each of the first, second-first, second-second, and third metal magazines may be marked with a predetermined unique ID or unique code.

[0104] According to the embodiment, metal plates are classified and loaded into the first, second-first, second-second or third metal magazine according to their thickness, whether they have a through trench, and their direction, and the information on the thickness, through trench and classification loading information for each individual metal plate and metal magazine is stored and managed in the upper server.

[0105] In addition, the unique information of each individual metal plate is precisely updated and managed, including information on which metal magazine it is loaded in.

[0106] As a result, in the subsequent stacking process, the unique ID of the 1st, 2nd-1st, 2nd-2nd or 3rd metal magazine is read to precisely match the stacking order and then the hot pressing process is carried out.

[0107] (4) Lamination process of insulating substrate and metal plate Next, the lamination process of the insulating substrate and the metal plate will be described with reference to FIG.

[0108] FIG. 8 is a conceptual diagram of an example in which an insulating substrate and a metal plate are laminated.

[0109] A first laminate set ST1 that will become the heat dissipation substrate 410 (see FIG. 10) of the embodiment is prepared (see FIG. 8).

[0110] 8, a first metal plate 421, a second-second metal plate 422b, a second-first metal plate 422a, an insulating substrate 410, a third metal plate 423, and a second carbon spacer (not shown) are sequentially stacked on a first carbon spacer (not shown). In an embodiment, graphite (not shown) may be stacked after a set of 10 stacked plates, but the present invention is not limited to this.

[0111] According to the embodiment, the stack unit set is placed in a hot press while maintaining alignment, and the hot pressing process is performed, thereby achieving a special technical effect of realizing a high-quality heat dissipation substrate having a hollow structure HE without misalignment of the stack set.

[0112] In addition, according to the embodiment, the laminate set is placed in the hot press while maintaining alignment, and the hot pressing process is performed. Carbon spacers are disposed on the top and bottom to offset pressure deviations, thereby forming a uniform pressure distribution and reducing the risk of cracks that may occur in the ceramic.

[0113] (5) Hot pressing process of insulating substrate and metal plate Next, the hot press joining process of the embodiment will be described with reference to FIG.

[0114] Referring to FIG. 9, a hot press process is performed in a vacuum on the laminate set placed in a hot press device (not shown), thereby manufacturing the heat dissipation substrate 400 for a power semiconductor module according to the embodiment as shown in FIG. 10.

[0115] The temperature of the hot pressing step may be about 900°C to 1,100°C. Preferably, the temperature of the hot pressing step may be about 950°C to 1,000°C, but is not limited thereto. The degree of vacuum in the hot pressing step is 1.0 x 10 -1 The degree of vacuum may be, but is not limited to, torr or more. The pressure in the hot pressing step may be, but is not limited to, a pressure of about 10 MPa to about 100 MPa.

[0116] In the prior art, various heat dissipation components and heat dissipation modules such as heat sinks, heat dissipation plates, heat pipes, vapor chambers, etc. have been adopted to solve the heat generation problem of electronic devices such as power semiconductor modules.

[0117] However, in conventional technology, separately manufactured heat dissipation components such as a vapor chamber heat spreader are attached to the heat dissipation substrate with a specified adhesive layer. In this case, not only does the heat transfer path from the electronic element, which is the heat source, to the vapor chamber heat spreader 102 become longer, but the heat transfer efficiency also decreases, and the working fluid does not vaporize sufficiently, resulting in a problem of reduced heat dissipation performance.

[0118] Furthermore, the difference in thermal expansion coefficient between the separately bonded components and the heat dissipation substrate may cause separation of the bonding interface or warping of the components, which may result in malfunction of the power semiconductor module.

[0119] As a result, one of the technical challenges of the embodiment is to solve the problem that when the vapor chamber heat spreader 102 is attached to the substrate 21 or the auxiliary substrate 21A by the adhesive 80, not only does the heat transfer path from the electronic element 20, which is the heat source, to the vapor chamber heat spreader 102 become longer, but also the heat transfer efficiency decreases due to the presence of a separate adhesive layer between the vapor chamber heat spreader 102 and the substrate 21 or the auxiliary substrate 21A, thereby reducing the heat dissipation performance.

[0120] In addition, one of the technical objectives of the embodiment is to solve the problem that when a heat dissipation substrate and a heat dissipation component are bonded with an adhesive layer, the difference in the thermal expansion coefficients of the bonded components causes separation of the bonding interface or warping of the components, resulting in malfunction of the power semiconductor module.

[0121] Meanwhile, in the conventional heat dissipation substrate technology field, heat dissipation problems were solved by separately attaching or placing various heat dissipation components such as heat sinks, heat dissipation plates, heat pipes, and vapor chambers on the heat dissipation substrate, but there was no consideration or research into forming heat dissipation components integrally on the metal plate that makes up the heat dissipation substrate.

[0122] Specifically, when directly bonding Cu metal plates to Cu metal plates, an oxide layer formed on the Cu surface prevents proper Cu to Cu bonding, and the oxide layer at the bonding interface induces high electrical and thermal resistance at the interface, degrading the thermal and electrical properties of the heat dissipation substrate.

[0123] Meanwhile, in the conventional heat dissipation substrate technical field, there has been no attempt to form a metal plate having a hollow structure integrally with a heat dissipation substrate, and there have been considerable technical difficulties in realizing this when researching internal comparison technology.

[0124] On the other hand, according to the power semiconductor module 500 including the heat dissipation substrate 400 for power semiconductors according to the embodiment, a hot press process is performed in a high temperature and high pressure vacuum environment, so that the heat dissipation substrate 400 itself can be embodied as a heat dissipation substrate integrally provided with the second metal plate 422 having a hollow structure HE that can seal a working fluid.

[0125] As a result, according to the embodiment, the heat transfer path between the power semiconductor element 100, which is the heat source, and the second metal plate 422 having the hollow structure HE is significantly shortened, thereby improving the heat transfer efficiency, and thereby efficiently evaporating the working fluid, resulting in a technical effect of significantly improving the heat dissipation performance.

[0126] In addition, according to the embodiment, the heat dissipation substrate 400 is provided with the second metal plate 422 having a hollow structure HE that can encapsulate the working fluid, and thus heat is transferred to the second metal plate 422 having the hollow structure HE without passing through a separate adhesive layer. This improves heat transfer efficiency and vaporizes the working fluid efficiently, resulting in a significant improvement in heat dissipation performance.

[0127] Furthermore, in the heat dissipation substrate 400 according to the embodiment, not only is the interface between the second metal plate 422 having a hollow structure HE and the first metal plate 421 integrally bonded thereto not substantially separated, but also the material of the second metal plate 422 having a hollow structure HE is the same as the material of the first metal plate 421 integrally formed thereto, eliminating the difference in thermal expansion coefficients between the two sides, thereby fundamentally preventing separation of the bonding interface or warping of the components, and resulting in a special technical effect of significantly improving the reliability of the power semiconductor module.

[0128] 6 Heatsink board inspection, etching and cutting processes, etc. The heat dissipation substrate inspection process, etching process, and cutting process will be described below. Each heat dissipation substrate manufactured by the hot press bonding process is subjected to a cleaning process, an inspection process, and an etching process. For example, the heat dissipation substrate 400 of the embodiment manufactured by the hot press bonding process is subjected to brush cleaning, water rinsing, and drying processes, but is not limited thereto.

[0129] In addition, in the embodiment, an ultrasonic inspection is performed on the bonding interface of the heat dissipation substrate manufactured by hot pressing. For example, according to the embodiment, the bonding interface of the individual heat dissipation substrate can be inspected for the thickness of the interface, the presence of voids, and the presence of cracks using ultrasonic inspection equipment.

[0130] According to the embodiment, after the hot press bonding process, the metal plate of each dummy area of ​​the heat dissipation substrate can be partially removed to open the unique code UC formed in the dummy area, thereby providing a special technical effect of precisely updating and managing inspection information regarding the interface thickness, presence of voids, and presence of cracks at the bonding interface of each individual heat dissipation substrate after the hot press process.

[0131] Thereafter, an etching process for forming a circuit pattern is performed on the heat dissipation substrate determined to be a non-defective product in the inspection process. For example, the circuit pattern can be formed on the third metal plate 423 by the etching process on the heat dissipation substrate 400 of the embodiment that has been subjected to the hot pressing process. For example, the third metal plate 423 can include a plurality of circuit patterns (not shown) formed by a patterning process such as etching, and the circuit patterns are electrically connected to the power semiconductor device 100.

[0132] 11a, one side of the circuit pattern of the third metal plate 423 may be electrically connected to the power semiconductor device 100 via a wiring 130a such as a wire. The other side of the circuit pattern of the third metal plate 423 may be connected to an external connection terminal. The external connection terminal may include an input power source, a motor, an inverter controller, etc.

[0133] The embodiment has a special technical effect that etching information (etchant, etching process conditions, etc.) for each individual heat sink substrate can be precisely updated and managed after the hot pressing process.

[0134] If the etching process for forming the circuit pattern is not performed, the substrate can be used as a heat dissipation component, and the process is the same as the heat dissipation substrate process after the etching process.

[0135] Next, the laser scribing process, inspection process, and cutting process for the heat dissipation substrate will be described. For example, an etching inspection is performed on a heat dissipation substrate after the etching process has been completed. For heat dissipation substrates that pass the etching inspection, a unique code UC is marked on the metal plate. For example, if a heat dissipation substrate includes nine snap areas, unique information UC can be marked on each snap area of ​​a metal plate on which a circuit pattern is not formed, for example, the first metal plate 421, for each snap. Marking the unique information UC on each snap area of ​​the first metal plate 421 may be performed after laser scribing.

[0136] Next, a laser scribing process and a breaking process are performed. In an embodiment, an inspection process is performed after the laser scribing process and before the breaking process. The inspection process may include a SAT (Scanning Ultrasonic Test) that uses ultrasonic waves to secondarily inspect for voids and cracks at the bonding interface. In addition, in the inspection process after the laser scribing process, an automatic visual inspection process is performed to analyze surface information such as surface roughness, surface pinhole inspection, protrusion inspection, and foreign substance inspection. In an embodiment, there is a special technical effect that secondary bonding interface inspection information and automatic visual inspection information for individual heat dissipation substrates can be precisely updated and managed after the etching process.

[0137] Thereafter, the final non-defective product is cut and separated to produce individual heat dissipation substrates 400, as shown in Figure 10. The bottom surface of the first metal plate 421 of the heat dissipation substrate 400 of the embodiment shown in Figure 10 is marked with a unique code UC before delivery. Therefore, according to this embodiment, the unique information, which can confirm the history of all processes from the initial storage stage of the product, is perfectly matched to the final product before delivery to the customer. This allows the customer to accurately understand the product's quality and production history before using it, and to quickly and accurately request A / S, etc., if necessary. However, simply marking product information on the heat dissipation substrate of the final product does not allow for perfect matching and management of film formation information, such as the thickness information of the insulating substrate, the thickness information of the metal plate, and the bonding interface information, which make up the product.

[0138] <Power conversion device including heat dissipation substrate> FIG. 11a is a first cross-sectional view of a power semiconductor module 500 including a heat dissipation substrate for power semiconductors according to an embodiment, and FIG. 12 is a second cross-sectional view of a power semiconductor module 500 including a heat dissipation substrate for power semiconductors according to an embodiment.

[0139] As described above, the final good heat dissipation substrate on which the circuit pattern is formed is cut and separated by snaps to manufacture the individual heat dissipation substrates 400 as shown in FIG.

[0140] 12, a working fluid inlet TH may be formed on one side of the second metal plate 422 of the heat dissipation substrate 400 of the power semiconductor module 500 according to the embodiment, and a working fluid (not shown) may be injected into the hollow structure HE, and the fluid inlet TH may be closed. The working fluid may be, but is not limited to, acetone, methanol, ethanol, or ultrapure water (DI-water).

[0141] According to this embodiment, heat generated from the power semiconductor device 100 is efficiently transferred to the second metal plate 422 of the heat dissipation substrate, and the working fluid vaporizes, absorbs the latent heat of vaporization, moves toward the lower first metal plate 421, condenses, and releases the latent heat of vaporization while condensing into a liquid. The condensed working fluid is absorbed by the porous structure of the second metal plate 422 and moves toward the insulating substrate 410. In this embodiment, the power semiconductor device 100, which is a heat source, may be disposed below the heat dissipation substrate 400, and the condensed working fluid may be moved by gravity.

[0142] 11b is a cross-sectional view of a power semiconductor module 502 including a heat dissipation substrate for power semiconductors according to a second embodiment. The second embodiment can adopt the technical features of the previous embodiments, and the main features of the second embodiment will be mainly described below.

[0143] Referring to FIG. 11b, the power semiconductor module 502 according to the second embodiment may include a heat dissipation substrate 400, a power semiconductor device 100 disposed on the heat dissipation substrate 400, and wiring 130a electrically connected to the power semiconductor device 100.

[0144] The power semiconductor module 502 according to the second embodiment may include, but is not limited to, a first metal plate 421, an insulating substrate 410, a second metal plate 422, and a third metal plate 423.

[0145] In particular, in the second embodiment, a hollow structure HE that can be filled with a working fluid is disposed between the power semiconductor device 100 and the insulating substrate 410 .

[0146] For example, in the second embodiment, the second metal plate 422 is disposed between the insulating substrate 410 and the third metal plate 423, and the second metal plate 422 may have a hollow structure HE. In the second embodiment, the power semiconductor device 100 is disposed on the third metal plate 423, but is not limited thereto.

[0147] The second metal plate 422 of the second embodiment may include a single metal plate or multiple metal plates. For example, the second metal plate 422 may include a 2-1 metal plate 422a having a first through trench E1 and a first body B1. The second metal plate 422 may further include a 2-2 metal plate 422b having a second body B2 and a second through trench E2. The first through trench E1 and the second through trench E2 of the second metal plate 422 may provide a three-dimensional hollow structure, and the hollow structure may be filled with a working fluid (not shown), such as acetone, methanol, ethanol, or ultrapure water.

[0148] In addition, the first body B1 and the second body B2 of the second metal plate 422 may have a porous structure that can contain or absorb a working fluid. For example, the first body B1 and the second body B2 of the second metal plate 422 may have a porous structure formed by a sintering process. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have fine grooves on their sidewalls. Alternatively, the first body B1 and the second body B2 of the second metal plate 422 may have a mesh-shaped porous structure.

[0149] Meanwhile, in the conventional heat dissipation substrate technology field, heat dissipation problems were solved by separately attaching or placing various heat dissipation components such as heat sinks, heat dissipation plates, heat pipes, and vapor chambers on the heat dissipation substrate, but there was no consideration or research into forming heat dissipation components integrally on the metal plate that makes up the heat dissipation substrate.

[0150] Furthermore, the heat dissipation substrate has an insulating substrate and a lower metal plate and an upper metal plate arranged above and below the insulating substrate, respectively, and the "upper metal plate" functions as a wiring substrate on which a circuit pattern is formed by etching in addition to its heat dissipation function.

[0151] As a result, in the conventional technical field of heat dissipation substrates, there has been no attempt to form a metal plate with a hollow structure integrally with the heat dissipation substrate, and in particular, with regard to having a hollow structure in the "upper metal plate" on which the circuit pattern is formed, there is a risk that the hollow structure will be damaged by etching, making it difficult to even consider this.

[0152] Furthermore, even if we take into consideration the hollow structure of the "upper metal plate," the insulating substrate is exposed by etching, and the circuit pattern is formed on the "upper metal plate." This makes it difficult to form precise circuit patterns, and as a result of considerable internal research, we found that this was an extremely difficult technical challenge.

[0153] Meanwhile, according to the second embodiment, a second metal plate 422 having a grid-shaped hollow structure is positioned on the upper side of the insulating substrate 410, and a hot press process is performed in a high-temperature and high-pressure vacuum environment, thereby realizing a heat dissipation substrate in which the second metal plate 422 having a hollow structure capable of sealing in a working fluid is integrally formed with the upper metal plate.

[0154] For example, according to the second embodiment, a second metal plate 422 is prepared in a grid shape in which a hollow structure is not arranged in a first region that is removed by etching, and a hollow structure is arranged in a second region that is not removed by etching, and then, in a stacked state, a hot press process is performed in a high temperature and high pressure vacuum environment.

[0155] For example, FIG. 11b is a cross-sectional view of the second region of the second metal plate 422 where the hollow structure HE is arranged.

[0156] Therefore, according to the second embodiment, even though a hollow structure is provided in the second region of the upper second metal plate 422 where the circuit pattern is to be formed, the subsequent etching process is performed in the first region where the hollow structure is not provided, thereby exposing the insulating substrate and forming the circuit pattern. As a result, the second embodiment has a special technical effect of resolving the technical contradiction that when the "upper metal plate" has a hollow structure, the hollow structure is damaged by etching.

[0157] According to the second embodiment, heat generated from the power semiconductor device 100 is efficiently transferred to the second metal plate 422, and the working fluid is vaporized in the hollow structure, absorbs the latent heat of vaporization, moves toward the lower insulating substrate 410 and the first metal plate 421, and condenses into a liquid while releasing the latent heat of vaporization. The condensed working fluid is then absorbed into the porous structure of the second metal plate 422 and moves toward the third metal plate 423.

[0158] According to the power semiconductor module 502 including the heat dissipation substrate 400 for power semiconductors of the second embodiment, a hot press process is performed in a high temperature and high pressure vacuum environment, so that the heat dissipation substrate 400 itself can be embodied as a heat dissipation substrate integrally provided with the second metal plate 422 having a hollow structure capable of sealing a working fluid.

[0159] As a result, according to the second embodiment, the heat transfer path between the power semiconductor element 100, which is the heat source, and the second metal plate 422 having a hollow structure is significantly shortened, improving the heat transfer efficiency and allowing the working fluid to be efficiently vaporized, resulting in the technical effect of significantly improving the heat dissipation performance.

[0160] In particular, in the second embodiment, the second metal plate 422 having a hollow structure capable of sealing a working fluid is disposed between the power semiconductor element 100 and the insulating substrate 410, thereby significantly shortening the heat transfer path between the power semiconductor element 100, which is the heat source, and the second metal plate 422 having a hollow structure, resulting in a technical effect of dramatically improving heat dissipation performance.

[0161] Furthermore, according to the second embodiment, it is possible to realize a heat dissipation substrate that is integrally provided with the second metal plate 422 having a hollow structure that can seal the working fluid in the heat dissipation substrate 400 itself without the need for a separate adhesive layer. As a result, heat is transferred to the second metal plate 422 having a hollow structure via the third metal plate 423 without passing through an adhesive layer that may cause thermal resistance, thereby improving heat transfer efficiency and significantly improving heat dissipation performance.

[0162] Furthermore, in the heat dissipation substrate 400 according to the second embodiment, not only is there no substantial difference in the interface between the hollow second metal plate 422 and the third metal plate 423 integrally bonded thereto without an adhesive layer, but the material of the hollow second metal plate 422 and the third metal plate 423 integrally formed thereon can be the same material. This eliminates the difference in thermal expansion coefficient between the second metal plate 422 and the third metal plate 423, thereby fundamentally preventing separation of the bonding interface or warpage of the components, resulting in a special technical effect of significantly improving the reliability of the power semiconductor module.

[0163] Next, FIG. 13 is a diagram showing a heat dissipation component 550 according to an embodiment disposed on a semiconductor device chip of a circuit board 610. As shown in FIG.

[0164] For example, posts 620 are spaced apart from one another on a circuit board 610, and a semiconductor chip is disposed inside the posts 620 of the circuit board 610. The semiconductor chip may be, but is not limited to, a Si semiconductor chip or a SiC semiconductor chip. The posts 620 may be made of an electrically insulating material with excellent heat transfer performance, but is not limited to this.

[0165] 13, the heat dissipation component 550 according to the embodiment may be bonded to the semiconductor device chip using a predetermined adhesive (not shown), but is not limited thereto. For example, the heat dissipation component 550 may be bonded to the semiconductor device chip by soldering, sintering bonding, transient liquid phase bonding (TLP bonding), ultrasonic bonding, etc.

[0166] The heat dissipation component 550 of the embodiment may include one or more metal plates and an insulating substrate 510. For example, the heat dissipation component 550 may include, but is not limited to, a first metal plate 521, a second metal plate 522, an insulating substrate 510, and a third metal plate 523.

[0167] The insulating substrate 510 can electrically insulate the second metal plate 522 from the third metal plate 523. The insulating substrate 510 can include a polycrystalline insulating substrate made of a ceramic material with high thermal conductivity. For example, the insulating substrate 510 can be made of one of AlN or Si3N4, but is not limited thereto, and can also be made of Al2O3, etc. Hereinafter, the insulating substrate 510 will be described as a polycrystalline substrate made of a ceramic material, but is not limited thereto, and can also include a single crystal substrate such as a sapphire substrate.

[0168] The first metal plate 521, the second metal plate 522, and the third metal plate 523 may include, but are not limited to, a Cu-based metal. For example, the first, second, and third metal plates 521, 522, and 523 may include at least one of Al, Ni, Ag, Mg, and Zn.

[0169] The second metal plate 522 has one side in contact with the insulating substrate 510 and the other side capable of dissipating heat.

[0170] In an embodiment, the second metal plate 522 may include a single metal plate or multiple metal plates. For example, the second metal plate 522 may include a 2-1 metal plate 522a having a first through-trench E1 and a second body B2. The second metal plate 522 may further include a 2-2 metal plate 522b having a first body B1 and a second through-trench E2.

[0171] The second metal plate 522 is illustrated as including a second-first metal plate 522a and a second-second metal plate 522b, but is not limited to this and may comprise a single metal plate.

[0172] In the second metal plate 522, the first through trench E1 and the second through trench E2 may be three-dimensionally connected to form a hollow structure HE, and the hollow structure HE may be filled with a working fluid (not shown) such as acetone, methanol, ethanol, or ultrapure water.

[0173] The first body B1 and the second body B2 of the second metal plate 522 may have a porous structure that can contain or absorb a working fluid. For example, the first body B1 and the second body B2 of the second metal plate 522 may have a porous structure formed by a sintering process. Alternatively, the first body B1 and the second body B2 of the second metal plate 522 may have fine grooves on their sidewalls. Alternatively, the first body B1 and the second body B2 of the second metal plate 522 may have a mesh-shaped porous structure.

[0174] According to this embodiment, heat generated from the semiconductor device chip is efficiently transferred to the second metal plate 522 of the heat dissipation substrate, causing the working fluid to vaporize and absorb the latent heat of evaporation, move toward the upper third metal plate 523, and condense into a liquid while releasing the latent heat of evaporation.The condensed working fluid is absorbed into the porous structure of the second metal plate 522 and moves toward the first metal plate 521.

[0175] Next, the third metal plate 523 may be in the form of a heat sink. For example, the third metal plate 523 may include, but is not limited to, a plurality of heat dissipation fins formed by a patterning process such as etching.

[0176] In addition, in an embodiment, the third metal plate 523 may include a second hollow structure (not shown) corresponding to the hollow structure HE. For example, the third metal plate 523 may include a 3-1 metal plate (not shown) and a 3-2 metal plate (not shown) sequentially arranged from the insulating substrate 510.

[0177] In addition, the third metal plate 523 includes a third through trench (not shown) and a fourth through trench (not shown) provided in a 3-1 metal plate (not shown) and a 3-2 metal plate (not shown), and the third through trench (not shown) and the fourth through trench (not shown) are three-dimensionally connected to form a second hollow structure, and the second hollow structure is filled with a working fluid (not shown), such as acetone, methanol, ethanol, or ultrapure water.

[0178] The heat dissipation component 550 according to the embodiment is subjected to a hot pressing process in a high temperature and high pressure vacuum environment, thereby integrally realizing the second metal plate 522 having a hollow structure HE that can seal the working fluid within the heat dissipation component 550 itself.

[0179] In addition, according to the embodiment, the heat transfer path between the semiconductor element, which is the heat source, and the second metal plate 522 having the hollow structure HE is shortened, thereby improving the heat transfer efficiency and efficiently evaporating the working fluid, resulting in a technical effect of significantly improving the heat dissipation performance.

[0180] In addition, according to the embodiment, the heat dissipation component 550 itself is provided with the second metal plate 522 having a hollow structure HE that can encapsulate the working fluid without a separate adhesive layer, so that heat is transferred to the second metal plate 522 having the hollow structure HE without passing through an adhesive layer that may induce thermal resistance. This improves heat transfer efficiency, allowing for efficient vaporization of the working fluid and significantly improving heat dissipation performance.

[0181] Furthermore, in the heat dissipation component 550 according to the embodiment, not only is there no substantial difference in the interface between the second metal plate 522 having a hollow structure HE and the first metal plate 521 integrally bonded thereto without an adhesive layer, but the material of the second metal plate 522 having a hollow structure HE can be the same as the material of the first metal plate 521 integrally formed thereto. This eliminates the difference in thermal expansion coefficient between the first metal plate 521 and the second metal plate 522, fundamentally preventing separation of the bonding interface or warpage of the components, resulting in a special technical effect of significantly improving the reliability of the heat dissipation component.

[0182] Next, FIG. 14 is a circuit diagram illustrating a power conversion device 1000 to which the power semiconductor module according to the embodiment is applied.

[0183] In the embodiments, the power semiconductor device is described as an inverter for an automobile for driving a motor, but the power semiconductor device of the embodiments can be applied to inverters, converters, etc. in the various technical fields mentioned above. Here, the automobile includes a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric vehicle (EV), a fuel cell electric vehicle (PCEV), etc.

[0184] The power conversion device 1000 according to the embodiment can receive DC power from a battery or a fuel cell, convert it into AC power, and supply the AC power to a predetermined load. For example, the power conversion device 1000 according to the embodiment can include an inverter, receive DC power from a battery, convert it into three-phase AC power, and supply it to a motor M, which can provide power to an electric vehicle, a fuel cell vehicle, etc.

[0185] The power converter 1000 according to the embodiment may include a power semiconductor device 100. The power semiconductor device 100 may be a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), but is not limited thereto, and may include an IGBT (Insulated Gate Bipolar Transistor).

[0186] For example, the power converter 1000 may include a plurality of power semiconductor devices 100a, 100b, 100c, 100d, 100e, and 100f and a plurality of diodes (not shown). Each of the plurality of diodes may be included in the power semiconductor devices 100a, 100b, 100c, 100d, 100e, and 100f in the form of an internal diode, but is not limited thereto and may be separately disposed.

[0187] The embodiment can convert DC power into AC power by controlling the on / off of the plurality of power semiconductor elements 100a-100f. For example, the power conversion device 1000 according to the embodiment can supply positive polarity power to the motor M by turning on the first power semiconductor element 100a and turning off the second power semiconductor element 100b during a first time interval of one cycle, and can supply negative polarity power to the motor M by turning off the first power semiconductor element 100a and turning on the second power semiconductor element 100b during a second time interval of one cycle.

[0188] In the embodiment, a group of power semiconductor devices arranged in series on the high-voltage line and low-voltage line on the input side may be referred to as an arm. For example, the first and second power semiconductor devices 100a and 100b may form a first arm 12a, the third and fourth power semiconductor devices 100c and 100d may form a second arm 12b, and the fifth and sixth power semiconductor devices 100e and 100f may form a third arm 12c.

[0189] 14 are packaged as one power semiconductor module, or the power semiconductor devices constituting each arm are packaged as one power semiconductor module. The upper and lower power semiconductor devices in each arm are controlled so as not to be turned on at the same time. For example, the first power semiconductor device 100a and the second power semiconductor device 100b in the first arm are not turned on at the same time but can be turned on and off alternately.

[0190] The power semiconductor device 100 of the embodiment may be a silicon carbide (SiC) power semiconductor device, which can operate in a high temperature and high voltage environment, and has a high switching speed while having low switching losses.

[0191] Although the present invention has been described above with reference to an embodiment, it will be readily apparent to those skilled in the art that the present invention can be modified and changed in various ways without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims

1. an insulating substrate; a lower metal plate disposed below the insulating substrate; an upper metal plate disposed on the insulating substrate; The heat dissipation substrate for a power semiconductor module, wherein the lower metal plate includes a hollow structure.

2. the lower metal plate includes a second metal plate bonded to the bottom surface of the insulating substrate; The heat dissipation substrate for a power semiconductor module according to claim 1 , further comprising: a first metal plate bonded to a bottom surface of the second metal plate.

3. The heat dissipation substrate for a power semiconductor module according to claim 2, wherein the second metal plate includes a second-1 metal plate having a plurality of first through trenches arranged in a first direction and bonded to the insulating substrate.

4. The heat dissipation substrate for a power semiconductor module according to claim 3, wherein the second metal plate has a plurality of second through trenches arranged in a second direction perpendicular to the first direction, and includes a second-2 metal plate bonded to a bottom surface of the second-1 metal plate.

5. the second-first metal plate includes a first body between a plurality of spaced-apart first through-trenches; 5. The heat dissipation substrate for a power semiconductor module according to claim 4, wherein the second-2 metal plate includes a second body between a plurality of spaced apart second through trenches.

6. the upper metal plate further includes a third metal plate bonded onto the insulating substrate; 3. The heat dissipation board for a power semiconductor module according to claim 2, wherein the thickness of the third metal plate is greater than the thickness of the first metal plate or the thickness of the second metal plate.

7. The heat dissipation board for a power semiconductor module according to claim 6 , wherein the third metal plate includes a circuit pattern on a surface thereof.

8. the second metal plate is directly bonded to the bottom surface of the insulating substrate without an adhesive layer; The heat dissipation substrate for a power semiconductor module according to claim 2 , wherein the first metal plate is directly bonded to the bottom surface of the second metal plate without an adhesive layer.

9. A heat dissipation substrate for a power semiconductor module according to any one of claims 1 to 8; a power semiconductor element disposed on the upper metal plate.

10. A power conversion device comprising the power semiconductor module of claim 9.

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