WO2024100894A1 - Dual-side cooled power module - Google Patents

Dual-side cooled power module Download PDF

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Publication number
WO2024100894A1
WO2024100894A1 PCT/JP2022/042109 JP2022042109W WO2024100894A1 WO 2024100894 A1 WO2024100894 A1 WO 2024100894A1 JP 2022042109 W JP2022042109 W JP 2022042109W WO 2024100894 A1 WO2024100894 A1 WO 2024100894A1
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Prior art keywords
power module
resin film
semiconductor element
copper
double
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PCT/JP2022/042109
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French (fr)
Japanese (ja)
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キム・ジョンドゥ
リ・ジョンソク
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サンケン電気株式会社
サンケン エレクトリック コリア株式会社
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Priority to PCT/JP2022/042109 priority Critical patent/WO2024100894A1/en
Publication of WO2024100894A1 publication Critical patent/WO2024100894A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/28—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/28—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection
    • H01L23/29—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the material, e.g. carbon

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  • the present invention relates to a double-sided cooled power module.
  • wide band gap semiconductor elements semiconductor elements that use wide band gap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) have been attracting attention as semiconductor elements for power semiconductor modules (also simply referred to as “power modules”).
  • Wide band gap semiconductor elements are capable of operating in high temperature environments compared to conventional semiconductor elements that use silicon, and also have excellent characteristics such as low loss and high speed operation. The use of these wide band gap semiconductor elements makes it possible to miniaturize power modules and improve their performance.
  • power modules are generally equipped with heat dissipation components such as heat sinks. These heat dissipation components dissipate heat generated by the semiconductor elements to the outside, stabilizing the operation of the power semiconductor module.
  • Dual side cooling (DSC) power modules have been proposed to efficiently dissipate heat from the top and bottom main surfaces of a semiconductor device on which a semiconductor element is mounted (Patent Documents 1-4, etc.).
  • An example of a conventional double-sided cooling power module described in Patent Document 2 is shown in FIG. 3.
  • the semiconductor element 1 is sandwiched between insulating circuit boards 30A and 30B (sometimes called DBC: Direct Bonding Copper) in which conductors 32A, 33A, 32B, and 33B such as copper (Cu) foil are bonded to both sides of ceramic insulating substrates 31A and 31B. Since the semiconductor element 1 is very thin (small), the installation position is adjusted using a spacer 34.
  • the space is filled with molded resin 18, and a lead frame 17, which serves as a terminal to the outside, is appropriately provided.
  • a lead frame 17 which serves as a terminal to the outside, is appropriately provided.
  • the present invention has been made to solve the above problems, and aims to provide a double-sided cooled power module that is highly reliable even at high temperatures.
  • the present invention has been made to achieve the above object, and provides a double-sided cooling power module comprising a semiconductor element and two insulated circuit boards that sandwich the semiconductor element, each of the two insulated circuit boards comprising an insulating resin film, a circuit section provided on the semiconductor element side of the resin film, and a heat dissipation section provided on the opposite side of the resin film to the semiconductor element, the circuit section comprising a wiring layer made of a copper-containing metal provided on the surface of the resin film, and a convex section made of a copper-containing metal that protrudes from the wiring layer towards the semiconductor element side and supports the semiconductor element, and the heat dissipation section comprises a copper-containing metal layer provided on the surface of the resin film.
  • Such double-sided cooled power modules can suppress damage such as cracks in high temperature environments, make it easy to control the flatness of the surface, and suppress structural problems such as mold voids, making them highly reliable even at high temperatures.
  • the copper-containing metal of the wiring layer in the circuit section and the copper-containing metal of the protruding section can be made of different materials.
  • the insulating circuit board can be provided with a filler material containing mold resin, solder resist, resin fill, or glass epoxy resin on the wiring layer where the convex portion of the circuit section is not provided.
  • a filler material containing mold resin, solder resist, resin fill, or glass epoxy resin on the wiring layer where the convex portion of the circuit section is not provided.
  • the insulating circuit board may have a window portion around the protruding portion of the circuit portion that penetrates the wiring layer to the surface of the resin film, and the window portion may be filled with a filler material.
  • the thickness of the resin film of the insulating circuit board can be 40 ⁇ m or more and less than 160 ⁇ m.
  • the double-sided cooled power module of the present invention can suppress damage such as cracks in high temperature environments, makes it easy to control the flatness of the surface, and can suppress structural problems such as mold voids, resulting in high reliability even at high temperatures.
  • FIG. 1 is a cross-sectional view showing an example of a double-sided cooled power module according to the present invention. 1A and 1B, a cross-sectional view of the upper insulating circuit board 10A is omitted, and a top view of the lower insulating circuit board 10B before resin is filled and before semiconductor elements are mounted.
  • FIG. 1 is a cross-sectional view showing an example of a conventional double-sided cooled power module.
  • FIG. 13 is a diagram showing the results of evaluation and comparison, by simulation, of the heat dissipation effect between a conventional double-sided-cooled power module using a ceramic substrate and a double-sided-cooled power module according to the present invention.
  • FIG. 11 is a diagram showing an evaluation and comparison of size (particularly thickness) between a conventional double-sided-cooled power module using a ceramic substrate and a double-sided-cooled power module according to the present invention.
  • FIG. 1 is a diagram showing a comparison of the assembly process (outline) between a conventional double-sided cooled power module using a ceramic substrate and a double-sided cooled power module according to the present invention.
  • FIG. 13 is a diagram showing a simulation result of thermal characteristics.
  • FIG. 1 is a diagram showing a comparison between a double-sided cooled power module according to the present invention and the prior art.
  • a double-sided cooling power module comprising a semiconductor element and two insulated circuit boards sandwiching the semiconductor element, each of the two insulated circuit boards comprising an insulating resin film, a circuit section provided on the semiconductor element side of the resin film, and a heat dissipation section provided on the resin film opposite the semiconductor element, the circuit section comprising a wiring layer made of a copper-containing metal provided on the surface of the resin film, and a convex section made of a copper-containing metal protruding from the wiring layer toward the semiconductor element side and supporting the semiconductor element, and the heat dissipation section comprising a copper-containing metal layer provided on the surface of the resin film, can suppress damage such as cracks in high-temperature environments, has easy control over the flatness of the surface, can suppress structural problems such as mold voids, and is highly reliable even at high temperatures, thereby completing the present invention.
  • the double-sided cooling power module 100 includes a semiconductor element 1 and two insulating circuit boards 10A and 10B that sandwich the semiconductor element 1.
  • the two insulating circuit boards 10A and 10B each include an insulating resin film 11A and 11B, a circuit section 12A and 12B provided on the semiconductor element side of the resin film 11A and 11B, and a heat dissipation section 13A and 13B provided on the opposite side of the resin film 11A and 11B from the semiconductor element.
  • the circuit section 12A and 12B each include a wiring layer 14A and 14B made of a copper-containing metal provided on the surface of the resin film, and a protrusion 15A and 15B made of a copper-containing metal that protrudes from the wiring layer 14A and 14B toward the semiconductor element 1 side and supports the semiconductor element 1.
  • the heat dissipation section 13A and 13B each include a copper-containing metal layer 16A and 16B provided on the surface of the resin film. Furthermore, lead terminals 17 for electrical connection to the outside and molding resin 18 for sealing the space with resin are provided as appropriate.
  • Each insulating circuit board 10A, 10B sandwich the semiconductor element 1.
  • Each insulating circuit board includes resin films 11A, 11B, circuit sections 12A, 12B provided on the semiconductor element side of the resin film, and heat dissipation sections 13A, 13B provided on the opposite side of the resin film to the semiconductor element.
  • the resin film according to the present invention is not particularly limited in material so long as it is insulating, but examples of materials that can be used include PET (polyethylene terephthalate), polyimide, polycarbonate, and polyacrylate. To improve high-temperature properties, it is preferable for the film to contain a filler such as silica, alumina, or zirconia. The film is capable of interfering with stress more effectively than ceramics.
  • Both the wiring layers 14A, 14B and the protrusions 15A, 15B are made of copper-containing metal, which may be the same, but are preferably made of different materials. If they are made of different materials, the thermal expansion coefficients of the wiring layers and the protrusions can be made different, making them more reliable even at high temperatures.
  • the copper-containing metal of the wiring layers can be high purity copper (OFC)
  • the copper-containing metal of the protrusions can be a copper alloy. Examples of copper alloys include C194, C7025, EFTEC 64T, and Alloy 42.
  • fillers 20A, 20B containing mold resin, solder resist, resin fill, or glass epoxy resin on the wiring layers 14A, 14B where the protrusions 15A, 15B of the circuit sections 12A, 12B are not provided. This provides higher reliability at high temperatures.
  • windows 19A, 19B that penetrate the wiring layers 14A, 14B to the surfaces of the resin films 11A, 11B can be provided, and the windows 19A, 19B can be provided with fillers 20A, 20B.
  • Heat dissipation sections 13A, 13B have copper-containing metal layers 16A, 16B.
  • the wiring layers 14A, 14B and protruding sections 15A, 15B of the circuit sections 12A, 12B, and the copper-containing metal layers 16A, 16B of the heat dissipation sections 13A, 13B are all layers made of copper-containing metal, but the composition and form of each metal may be the same or different.
  • the structures of the two insulating circuit boards 10A and 10B are shown as symmetrical, but the patterns of the circuit parts of the two insulating circuit boards, the wiring layers, the protrusions, the metal composition of the copper-containing metal layer of the heat dissipation part, etc. may be the same or different.
  • FIG. 2 shows a cross-section of the upper insulating circuit board 10A in FIG. 1, and a top view of the lower insulating circuit board 10B in a state where no resin is filled and no semiconductor element is mounted.
  • the upper insulating circuit board of the double-sided cooling power module is not shown for the sake of explanation.
  • the right diagram of FIG. 2 is a plan view of the lower insulating circuit board in the left diagram in a state where no semiconductor element 1 is mounted and no filler material 20B is filled, as seen from above.
  • the convex portion and the window portion can be formed by etching the copper-containing metal layer. If the etched area is filled with an adhesive or resin material, the effect of the difference in the thermal expansion coefficient of the copper-containing metal layer can be reduced. The mismatch between the thermal expansion coefficients of the convex portion and the semiconductor element is reduced, and cracks in the semiconductor element are improved. In addition, by filling the gaps between the protrusions 15B and the window portions 19B with adhesive or resin material (filler), and providing the window portions with filler, mold flow and track voids can be improved.
  • the arrangement and shape of the wiring layer 14B made of copper-containing metal provided on the surface of the resin film, the convex portion 15B, and the window portion 19B of the circuit portion are not particularly limited.
  • the adhesive or resin material may include fillers such as Al2O3 , BN, or AlN, mold resin, solder resist (PSR: photosensitive solder resist), resin fill, or glass epoxy resin (FR4: Flame Retardant Type 4), solder mask, mold compound, epoxy, etc.
  • fillers such as Al2O3 , BN, or AlN
  • PSR photosensitive solder resist
  • resin fill or glass epoxy resin (FR4: Flame Retardant Type 4)
  • FR4 Flame Retardant Type 4
  • the semiconductor element 1 mounted on the double-sided cooling power module according to the present invention is not particularly limited as long as it is a power semiconductor element.
  • a wide band gap semiconductor element using a wide band gap semiconductor such as silicon carbide (SiC) or gallium nitride (GaN) can be used.
  • Such a semiconductor element is installed on the convex portion of the circuit part via an adhesive layer 21 such as solder paste or Ag paste.
  • Figure 4 shows the results of a simulation evaluation and comparison of the heat dissipation effect of a conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention.
  • a water-cooled jacket was attached to cool the conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention using a resin film, and the temperature characteristics were simulated and compared when the module reached a high temperature state.
  • the temperature near the center of the upper 1/3 region is compared by the shade of color.
  • the double-sided cooling power module according to the present invention has a low temperature rise (light color) and has a high heat dissipation effect.
  • the double-sided cooled power module of the present invention does not use spacers when mounting the semiconductor elements, as is the case when using conventional ceramic substrates. Therefore, in the double-sided cooled power module of the present invention, the semiconductor elements are directly attached to the insulating circuit substrate, and the heat dissipation effect is higher than when spacers are used. In this way, the one using the resin film has higher thermal cycle reliability than the one using the ceramic substrate.
  • the thickness of the copper-containing metal layer in the circuit section and heat dissipation section could not be made thicker than the ceramic substrate. This is because if the copper-containing metal layer is thicker than the ceramic, the ceramic is more likely to crack.
  • resin film makes it possible to make the copper-containing metal layer in the circuit section and heat dissipation section thicker, which further promotes heat dissipation, increases power, and more effectively suppresses the occurrence of cracks.
  • Figure 5 shows an evaluation and comparison of the size (particularly thickness) of a conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention.
  • the evaluation was performed on the premise that the semiconductor elements (Dies) and other elements common to both are equivalent. Since each layer has its own manufacturing tolerance, as the number of layers increases, the overall thickness increases and the cumulative tolerance also increases.
  • the thickness of the entire package varies within a range of about 0.24 to 0.26 mm. If such variation occurs in the multiple semiconductor elements, the thickness of the entire power module also varies, and the flatness deteriorates.
  • the thickness of the entire package is about 0.22 mm.
  • the double-sided cooling power module according to the present invention requires fewer materials to be managed, and therefore the dimensional accuracy is improved, and the overall thickness and flatness can be easily managed. As a result, no gap is formed between the heat sink such as a water jacket, contact is improved, and thermal performance can be expected to be improved.
  • Figure 6 is a diagram showing a comparison of the assembly process (outline) of a conventional double-sided cooled power module using a ceramic substrate and a double-sided cooled power module according to the present invention.
  • the process of mounting semiconductor elements on spacers can be omitted. Therefore, it can be seen that the assembly process is simplified compared to the conventional method. Furthermore, it is possible to reduce costs by reducing the amount of spacers and adhesives (solder, epoxy, silver paste, etc.) used, and to increase UPH (Units Per Hour: the total number of mounted parts that can be mounted per hour) by simplifying the process.
  • UPH Units Per Hour: the total number of mounted parts that can be mounted per hour
  • Figure 7 shows the results of the simulation of thermal characteristics.
  • the junction temperature when a ceramic substrate is used (conventional example) was used as the reference value, and the film thickness of the resin film was used as a parameter in the simulation.
  • the film thickness of the resin film is set to a range of less than 160 ⁇ m to show better performance at high heat, it is possible to achieve a lower junction temperature with better heat dissipation characteristics and more stable performance than conventional films. It is preferable that the film thickness of the resin film is 40 ⁇ m or more from the viewpoints of the size of the filler contained in the film to improve high-temperature characteristics, the strength of the film, and stability.
  • FIG. 8 Advantages of the double-sided cooling power module according to the present invention described above are summarized in FIG. 8 in comparison with the conventional technology.
  • “Type #1” in FIG. 8 is the conventional double-sided cooling power module described using FIG. 3, and is described in, for example, Patent Document 2.
  • “Type #2” in FIG. 8 is a conventional double-sided cooling power module using an insulating circuit board in which a Cu layer is formed on the surface of a ceramic substrate by a printing method (TPC method: Thick Print Copper method), and is described in, for example, Patent Document 3.
  • TPC method Thick Print Copper method
  • the double-sided cooling power module according to the present invention can suppress damage such as cracks in high-temperature environments, which was a conventional problem, can easily control the flatness of the surface, can suppress structural problems such as mold voids, and is highly reliable even at high temperatures.
  • the present invention is not limited to the above-described embodiments.
  • the above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and provides similar effects is included within the technical scope of the present invention.

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  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)

Abstract

The present invention is a dual-side cooled power module comprising a semiconductor element and two insulated circuit boards sandwiching the semiconductor element, wherein: each of the two insulated circuit boards is provided with an insulating resin film, a circuit part provided to the semiconductor-element side of the resin film, and a heat-dissipating part provided to the opposite side of the resin film from the semiconductor element; the circuit part is provided with a wiring layer that is made from a copper-containing metal and is provided to the resin film surface, and a projection that is made from the copper-containing metal, projects toward the semiconductor-element side from the wiring layer, and supports the semiconductor element; and the heat-dissipating part is provided with a copper-containing metal layer provided to the resin film surface. This makes it possible to provide a dual-side cooled power module that is highly reliable even at high temperatures, the dual-side cooled power module being such that damage such as cracks can be suppressed even in high-temperature environments, control of surface flatness is easy, and structural problems such as mold voids can also be suppressed.

Description

両面冷却パワーモジュールDouble-sided cooled power module
　本発明は、両面冷却パワーモジュールに関する。 The present invention relates to a double-sided cooled power module.
　近年、パワー半導体モジュール（単に、「パワーモジュール」ともいう）向けの半導体素子として、炭化ケイ素（ＳｉＣ）や窒化ガリウム（ＧａＮ）のようなワイドバンドギャップ半導体を使用する半導体素子（以下、「ワイドバンドギャップ半導体素子」ということもある）が注目されている。ワイドバンドギャップ半導体素子は、シリコンを使用する従来の半導体素子と比較して高温環境での動作が可能であり、低損失、高速動作などの優れた特性を併せ備えている。このワイドバンドギャップ半導体素子を用いることで、パワーモジュールを小型高性能化できる。 In recent years, semiconductor elements (hereinafter sometimes referred to as "wide band gap semiconductor elements") that use wide band gap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) have been attracting attention as semiconductor elements for power semiconductor modules (also simply referred to as "power modules"). Wide band gap semiconductor elements are capable of operating in high temperature environments compared to conventional semiconductor elements that use silicon, and also have excellent characteristics such as low loss and high speed operation. The use of these wide band gap semiconductor elements makes it possible to miniaturize power modules and improve their performance.
　ところで、パワーモジュールは、一般に、ヒートシンクなどの放熱部材を備えている。この放熱部材により、半導体素子で生じる熱は外部に発散されてパワー半導体モジュールの動作は安定化される。 Incidentally, power modules are generally equipped with heat dissipation components such as heat sinks. These heat dissipation components dissipate heat generated by the semiconductor elements to the outside, stabilizing the operation of the power semiconductor module.
米国特許第９３９０９９６号明細書U.S. Pat. No. 9,390,996 米国特許出願公開第２０１９／０３４１３３２号明細書US Patent Application Publication No. 2019/0341332 中国特許第１０９９２０７８５号明細書Chinese Patent No. 109920785 米国特許第１０００２８２１号明細書U.S. Pat. No. 10,002,821
　半導体素子が搭載された半導体装置の上下の主面から効率よく放熱を行うための、両面冷却（ＤＳＣ：Ｄｕａｌ　ｓｉｄｅ　ｃｏｏｌｉｎｇ）パワーモジュールが提案されている（特許文献１－４等）。特許文献２に記載された従来の両面冷却パワーモジュールの一例を、図３に示す。図３に示すように従来の両面冷却パワーモジュール２００では、セラミック製の絶縁基板３１Ａ、３１Ｂの両面に銅（Ｃｕ）箔などの導電体３２Ａ、３３Ａ、３２Ｂ、３３Ｂを接合した絶縁回路基板３０Ａ、３０Ｂ（ＤＢＣ：Ｄｉｒｅｃｔ　Ｂｏｎｄｉｎｇ　Ｃｕｐｐｅｒということもある）により半導体素子１を挟持していた。なお、半導体素子１は非常に薄い（小さい）ため、スペーサ３４を用いて設置位置の調整を行っている。空間にはモールド樹脂１８が樹脂封止され、また、外部への端子となるリードフレーム１７等が適宜設けられる。なお、絶縁回路基板３０Ａ、３０Ｂの半導体素子１の搭載側の面において、エッチングにより導電体の一部を除去している。 Dual side cooling (DSC) power modules have been proposed to efficiently dissipate heat from the top and bottom main surfaces of a semiconductor device on which a semiconductor element is mounted (Patent Documents 1-4, etc.). An example of a conventional double-sided cooling power module described in Patent Document 2 is shown in FIG. 3. As shown in FIG. 3, in the conventional double-sided cooling power module 200, the semiconductor element 1 is sandwiched between insulating circuit boards 30A and 30B (sometimes called DBC: Direct Bonding Copper) in which conductors 32A, 33A, 32B, and 33B such as copper (Cu) foil are bonded to both sides of ceramic insulating substrates 31A and 31B. Since the semiconductor element 1 is very thin (small), the installation position is adjusted using a spacer 34. The space is filled with molded resin 18, and a lead frame 17, which serves as a terminal to the outside, is appropriately provided. On the surfaces of the insulating circuit boards 30A and 30B on which the semiconductor element 1 is mounted, part of the conductor is removed by etching.
　従来のセラミック製の絶縁基板を用いた両面冷却では、高温での熱膨張率（ＣＴＥ：Ｃｏｅｆｆｉｃｉｅｎｔ　ｏｆ　Ｔｈｅｒｍａｌ　Ｅｘｐａｎｓｉｏｎ）の差に起因する高い割れ率が問題となっていた。また、高温で硬化することにより生じる厚さ変化による積層材料の累積公差は、表面の平坦性の制御を困難にしていた。さらに、銅（Ｃｕ）箔などの導電体のパターン間の空間にモールドボイドが生じ、構造上の問題もあった。 With conventional double-sided cooling using ceramic insulating substrates, a high cracking rate was an issue due to differences in the coefficient of thermal expansion (CTE) at high temperatures. In addition, the cumulative tolerance of the laminated material due to thickness changes caused by hardening at high temperatures made it difficult to control the flatness of the surface. Furthermore, mold voids occurred in the spaces between patterns of conductors such as copper (Cu) foil, causing structural problems.
　本発明は、上記問題を解決するためになされたものであり、高温でも信頼性が高い両面冷却パワーモジュールを提供することを目的とする。 The present invention has been made to solve the above problems, and aims to provide a double-sided cooled power module that is highly reliable even at high temperatures.
　本発明は、上記目的を達成するためになされたものであり、半導体素子と、該半導体素子を挟持する２つの絶縁回路基板を備えた両面冷却パワーモジュールであって、前記２つの絶縁回路基板は、それぞれ、絶縁性の樹脂フィルムと、該樹脂フィルムの前記半導体素子側に設けられた回路部と、前記樹脂フィルムの前記半導体素子とは反対側に設けられた放熱部とを備え、前記回路部は、前記樹脂フィルム表面に設けられた銅含有金属からなる配線層と、該配線層から前記半導体素子側に向けて突出して前記半導体素子を支持する銅含有金属からなる凸部を備え、前記放熱部は、前記樹脂フィルム表面に設けられた銅含有金属層を備えるものである両面冷却パワーモジュールを提供する。 The present invention has been made to achieve the above object, and provides a double-sided cooling power module comprising a semiconductor element and two insulated circuit boards that sandwich the semiconductor element, each of the two insulated circuit boards comprising an insulating resin film, a circuit section provided on the semiconductor element side of the resin film, and a heat dissipation section provided on the opposite side of the resin film to the semiconductor element, the circuit section comprising a wiring layer made of a copper-containing metal provided on the surface of the resin film, and a convex section made of a copper-containing metal that protrudes from the wiring layer towards the semiconductor element side and supports the semiconductor element, and the heat dissipation section comprises a copper-containing metal layer provided on the surface of the resin film.
　このような両面冷却パワーモジュールによれば、高温環境での割れなどの破損を抑制でき、表面の平坦性の制御が容易であり、モールドボイドなどの構造上の問題も抑制可能なものであり、高温でも信頼度の高いものとなる。 Such double-sided cooled power modules can suppress damage such as cracks in high temperature environments, make it easy to control the flatness of the surface, and suppress structural problems such as mold voids, making them highly reliable even at high temperatures.
　このとき、前記回路部における前記配線層の銅含有金属と前記凸部の銅含有金属は、異なる材料からなるものとすることができる。 In this case, the copper-containing metal of the wiring layer in the circuit section and the copper-containing metal of the protruding section can be made of different materials.
　これにより、配線層と凸部の熱膨張係数を異なるものとすることができ、高温でもより信頼度の高いものとできる。 This allows the wiring layer and the protrusions to have different thermal expansion coefficients, making them more reliable even at high temperatures.
　このとき、前記絶縁回路基板は、前記回路部の前記凸部が設けられていない前記配線層上に、モールドレジン、ソルダーレジスト、レジンフィル又はガラスエポキシ樹脂を含む充填材を備えるものとすることができる。これは、前記凸部が設けられていない前記配線層上が充填材の充填や塗布等により埋められ、前記凸部上端面を露出させた状態にすることである。 In this case, the insulating circuit board can be provided with a filler material containing mold resin, solder resist, resin fill, or glass epoxy resin on the wiring layer where the convex portion of the circuit section is not provided. This means that the wiring layer where the convex portion is not provided is filled by filling or applying a filler material, leaving the upper end surface of the convex portion exposed.
　これにより、高温での信頼度がより高いものとなる。 This makes it more reliable at high temperatures.
　このとき、前記絶縁回路基板は、前記回路部の前記凸部の周囲に、前記樹脂フィルムの表面まで前記配線層を貫通する窓部を備え、前記窓部に充填材を備えるものとすることができる。 In this case, the insulating circuit board may have a window portion around the protruding portion of the circuit portion that penetrates the wiring layer to the surface of the resin film, and the window portion may be filled with a filler material.
　これにより、モールドフロー及びトラックボイドの改善を図ることができる。 This will help improve mold flow and track voids.
　このとき、前記絶縁回路基板の前記樹脂フィルムの厚さは４０μｍ以上、１６０μｍ未満とすることができる。 In this case, the thickness of the resin film of the insulating circuit board can be 40 μm or more and less than 160 μm.
　これにより、放熱特性により優れるものとなる。 This results in better heat dissipation properties.
　以上のように、本発明の両面冷却パワーモジュールによれば、高温環境での割れなどの破損を抑制でき、表面の平坦性の制御が容易であり、モールドボイドなどの構造上の問題も抑制可能なものであり、高温でも信頼度の高いものとなる。 As described above, the double-sided cooled power module of the present invention can suppress damage such as cracks in high temperature environments, makes it easy to control the flatness of the surface, and can suppress structural problems such as mold voids, resulting in high reliability even at high temperatures.
本発明に係る両面冷却パワーモジュールの一例を示す図（断面）である。FIG. 1 is a cross-sectional view showing an example of a double-sided cooled power module according to the present invention. 図１において上側の絶縁回路基板１０Ａを省略した図（断面）と、樹脂の充填及び半導体素子を搭載していない状態の、下側の絶縁回路基板１０Ｂの上面図を示す。1A and 1B, a cross-sectional view of the upper insulating circuit board 10A is omitted, and a top view of the lower insulating circuit board 10B before resin is filled and before semiconductor elements are mounted. 従来の両面冷却パワーモジュールの一例を示す図（断面）である。FIG. 1 is a cross-sectional view showing an example of a conventional double-sided cooled power module. セラミック基板を用いた従来の両面冷却パワーモジュールと、本発明に係る両面冷却パワーモジュールとの放熱効果をシミュレーションにより評価・比較した結果を示す図である。FIG. 13 is a diagram showing the results of evaluation and comparison, by simulation, of the heat dissipation effect between a conventional double-sided-cooled power module using a ceramic substrate and a double-sided-cooled power module according to the present invention. セラミック基板を用いた従来の両面冷却パワーモジュールと本発明に係る両面冷却パワーモジュールについて、サイズ（特に厚さ）の評価・比較を示す図である。FIG. 11 is a diagram showing an evaluation and comparison of size (particularly thickness) between a conventional double-sided-cooled power module using a ceramic substrate and a double-sided-cooled power module according to the present invention. セラミック基板を用いた従来の両面冷却パワーモジュールと本発明に係る両面冷却パワーモジュールの、組立て工程（概略）の比較を示す図である。FIG. 1 is a diagram showing a comparison of the assembly process (outline) between a conventional double-sided cooled power module using a ceramic substrate and a double-sided cooled power module according to the present invention. 熱特性についてのシミュレーション結果を示す図である。FIG. 13 is a diagram showing a simulation result of thermal characteristics. 本発明に係る両面冷却パワーモジュールと従来技術との比較を示す図である。FIG. 1 is a diagram showing a comparison between a double-sided cooled power module according to the present invention and the prior art.
　以下、本発明を詳細に説明するが、本発明はこれらに限定されるものではない。 The present invention is described in detail below, but is not limited to these.
　上述のように、高温でも信頼性が高い両面冷却パワーモジュールが求められていた。 As mentioned above, there was a demand for a double-sided cooled power module that was highly reliable even at high temperatures.
　本発明者らは、上記課題について鋭意検討を重ねた結果、半導体素子と、該半導体素子を挟持する２つの絶縁回路基板を備えた両面冷却パワーモジュールであって、前記２つの絶縁回路基板は、それぞれ、絶縁性の樹脂フィルムと、該樹脂フィルムの前記半導体素子側に設けられた回路部と、前記樹脂フィルムの前記半導体素子とは反対側に設けられた放熱部とを備え、前記回路部は、前記樹脂フィルム表面に設けられた銅含有金属からなる配線層と、該配線層から前記半導体素子側に向けて突出して前記半導体素子を支持する銅含有金属からなる凸部を備え、前記放熱部は、前記樹脂フィルム表面に設けられた銅含有金属層を備えるものである両面冷却パワーモジュールにより、高温環境での割れなどの破損を抑制でき、表面の平坦性の制御が容易であり、モールドボイドなどの構造上の問題も抑制可能なものであり、高温でも信頼度の高いものとなることを見出し、本発明を完成した。 As a result of intensive research into the above-mentioned problems, the inventors have found that a double-sided cooling power module comprising a semiconductor element and two insulated circuit boards sandwiching the semiconductor element, each of the two insulated circuit boards comprising an insulating resin film, a circuit section provided on the semiconductor element side of the resin film, and a heat dissipation section provided on the resin film opposite the semiconductor element, the circuit section comprising a wiring layer made of a copper-containing metal provided on the surface of the resin film, and a convex section made of a copper-containing metal protruding from the wiring layer toward the semiconductor element side and supporting the semiconductor element, and the heat dissipation section comprising a copper-containing metal layer provided on the surface of the resin film, can suppress damage such as cracks in high-temperature environments, has easy control over the flatness of the surface, can suppress structural problems such as mold voids, and is highly reliable even at high temperatures, thereby completing the present invention.
　以下、図面を参照して説明する。 The following explanation will be given with reference to the drawings.
　［両面冷却パワーモジュール］
　まず、本発明に係る両面冷却パワーモジュールについて、図１を参照しながら説明する。図１に示されるように、本発明に係る両面冷却パワーモジュール１００は、半導体素子１と、半導体素子１を挟持する２つの絶縁回路基板１０Ａ、１０Ｂを備えている。２つの絶縁回路基板１０Ａ、１０Ｂは、それぞれ、絶縁性の樹脂フィルム１１Ａ、１１Ｂと、樹脂フィルム１１Ａ、１１Ｂの半導体素子側に設けられた回路部１２Ａ、１２Ｂと、樹脂フィルム１１Ａ、１１Ｂの半導体素子とは反対側に設けられた放熱部１３Ａ、１３Ｂとを備えている。回路部１２Ａ、１２Ｂは、それぞれ、樹脂フィルム表面に設けられた銅含有金属からなる配線層１４Ａ、１４Ｂと、配線層１４Ａ、１４Ｂから半導体素子１側に向けて突出して半導体素子１を支持する銅含有金属からなる凸部１５Ａ、１５Ｂを備えている。放熱部１３Ａ、１３Ｂは、樹脂フィルム表面に設けられた銅含有金属層１６Ａ、１６Ｂを備える。また、外部と電気的に接続するためのリード端子１７や、空間を樹脂封止するモールド樹脂１８が適宜設けられる。 [Double-sided cooling power module]
First, the double-sided cooling power module according to the present invention will be described with reference to Fig. 1. As shown in Fig. 1, the double-sided cooling power module 100 according to the present invention includes a semiconductor element 1 and two insulating circuit boards 10A and 10B that sandwich the semiconductor element 1. The two insulating circuit boards 10A and 10B each include an insulating resin film 11A and 11B, a circuit section 12A and 12B provided on the semiconductor element side of the resin film 11A and 11B, and a heat dissipation section 13A and 13B provided on the opposite side of the resin film 11A and 11B from the semiconductor element. The circuit section 12A and 12B each include a wiring layer 14A and 14B made of a copper-containing metal provided on the surface of the resin film, and a protrusion 15A and 15B made of a copper-containing metal that protrudes from the wiring layer 14A and 14B toward the semiconductor element 1 side and supports the semiconductor element 1. The heat dissipation section 13A and 13B each include a copper-containing metal layer 16A and 16B provided on the surface of the resin film. Furthermore, lead terminals 17 for electrical connection to the outside and molding resin 18 for sealing the space with resin are provided as appropriate.
　（絶縁回路基板）
　次に、絶縁回路基板の詳細について説明する。２つの絶縁回路基板１０Ａ、１０Ｂは半導体素子１を挟持するものである。それぞれの絶縁回路基板は、樹脂フィルム１１Ａ、１１Ｂと、樹脂フィルムの半導体素子側に設けられた回路部１２Ａ、１２Ｂと、樹脂フィルムの半導体素子とは反対側に設けられた放熱部１３Ａ、１３Ｂとを備えている。 (Insulated circuit board)
Next, the insulating circuit boards will be described in detail. Two insulating circuit boards 10A, 10B sandwich the semiconductor element 1. Each insulating circuit board includes resin films 11A, 11B, circuit sections 12A, 12B provided on the semiconductor element side of the resin film, and heat dissipation sections 13A, 13B provided on the opposite side of the resin film to the semiconductor element.
　本発明に係る樹脂フィルムは絶縁性のものであれば材料は特に限定されないが、例えばＰＥＴ（ｐｏｌｙｅｔｈｙｌｅｎｅ　ｔｅｒｅｐｈｔｈａｌａｔｅ）、ポリイミド、ポリカーボネート、ポリアクリレートなどを使用することができる。高温特性を向上するために、フィルムとして、シリカ、アルミナ、ジルコニアなどのフィラーを混合させたものが好ましい。フィルムはセラミックよりも効果的にストレスを干渉することが可能である。 The resin film according to the present invention is not particularly limited in material so long as it is insulating, but examples of materials that can be used include PET (polyethylene terephthalate), polyimide, polycarbonate, and polyacrylate. To improve high-temperature properties, it is preferable for the film to contain a filler such as silica, alumina, or zirconia. The film is capable of interfering with stress more effectively than ceramics.
　配線層１４Ａ、１４Ｂと凸部１５Ａ、１５Ｂはともに銅含有金属からなるものであり、これらは、同じであっても良いが、異なる材料とすることが好ましい。異なる材料とすれば、配線層と凸部の熱膨張係数を異なるものとすることができ、高温でもより信頼度の高いものとできる。例えば、配線層の銅含有金属を高純度銅（ＯＦＣ）、凸部の銅含有金属を銅合金とすることができる。銅合金としては、Ｃ１９４、Ｃ７０２５、ＥＦＴＥＣ　６４Ｔ、Ａｌｌｏｙ　４２などが挙げられる。 Both the wiring layers 14A, 14B and the protrusions 15A, 15B are made of copper-containing metal, which may be the same, but are preferably made of different materials. If they are made of different materials, the thermal expansion coefficients of the wiring layers and the protrusions can be made different, making them more reliable even at high temperatures. For example, the copper-containing metal of the wiring layers can be high purity copper (OFC), and the copper-containing metal of the protrusions can be a copper alloy. Examples of copper alloys include C194, C7025, EFTEC 64T, and Alloy 42.
　回路部１２Ａ、１２Ｂの凸部１５Ａ、１５Ｂが設けられていない配線層１４Ａ、１４Ｂ上には、モールドレジン、ソルダーレジスト、レジンフィル又はガラスエポキシ樹脂を含む充填材２０Ａ、２０Ｂを備えることが好ましい。これにより、高温での信頼度がより高いものとなる。 It is preferable to provide fillers 20A, 20B containing mold resin, solder resist, resin fill, or glass epoxy resin on the wiring layers 14A, 14B where the protrusions 15A, 15B of the circuit sections 12A, 12B are not provided. This provides higher reliability at high temperatures.
　また、回路部１２Ａ、１２Ｂの凸部１５Ａ、１５Ｂの周囲に、樹脂フィルム１１Ａ、１１Ｂの表面まで配線層１４Ａ、１４Ｂを貫通する窓部１９Ａ、１９Ｂを設け、窓部１９Ａ、１９Ｂに充填材２０Ａ、２０Ｂを備えたものとすることもできる。このようなものとすることで、モールドフロー及びトラックボイドの改善を図ることができる。 Also, around the protruding parts 15A, 15B of the circuit parts 12A, 12B, windows 19A, 19B that penetrate the wiring layers 14A, 14B to the surfaces of the resin films 11A, 11B can be provided, and the windows 19A, 19B can be provided with fillers 20A, 20B. By doing so, it is possible to improve mold flow and track voids.
　放熱部１３Ａ、１３Ｂは銅含有金属層１６Ａ、１６Ｂを備えている。回路部１２Ａ、１２Ｂの配線層１４Ａ、１４Ｂや凸部１５Ａ、１５Ｂと、放熱部１３Ａ、１３Ｂの銅含有金属層１６Ａ、１６Ｂは、ともに銅含有金属からなる層であるが、それぞれの金属の組成や形態などは同じであっても良いし、異なっていてもよい。 Heat dissipation sections 13A, 13B have copper-containing metal layers 16A, 16B. The wiring layers 14A, 14B and protruding sections 15A, 15B of the circuit sections 12A, 12B, and the copper-containing metal layers 16A, 16B of the heat dissipation sections 13A, 13B are all layers made of copper-containing metal, but the composition and form of each metal may be the same or different.
　なお、図１では、２つの絶縁回路基板１０Ａ、１０Ｂの構造を対称的なものとして記載しているが、２つの絶縁回路基板のそれぞれの回路部のパターン、配線層、凸部、放熱部の銅含有金属層の金属組成等は、同じであっても異なっていてもよい。 In FIG. 1, the structures of the two insulating circuit boards 10A and 10B are shown as symmetrical, but the patterns of the circuit parts of the two insulating circuit boards, the wiring layers, the protrusions, the metal composition of the copper-containing metal layer of the heat dissipation part, etc. may be the same or different.
　図２は、図１において上側の絶縁回路基板１０Ａを省略した図（断面）と、樹脂の充填及び半導体素子を搭載していない状態の、下側の絶縁回路基板１０Ｂの上面図を示す。図２の左図では、説明のために両面冷却パワーモジュールのうち、上側の絶縁回路基板を記載していない。図２の右図は、左図において半導体素子１を搭載していない状態かつ充填材２０Ｂを充填していない状態の下側の絶縁回路基板を、上方から見た平面図である。図２に示すように、凸部１５Ｂの周囲に、樹脂フィルム１１Ｂの表面まで配線層１４Ｂを貫通する窓部１９Ｂを設けることが好ましい。なお、凸部や窓部の形成は、銅含有金属層をエッチングすることにより行うことができる。そして、エッチングした領域を接着剤や樹脂材料で充填すると、銅含有金属層の熱膨張係数差の影響を小さくすることができる。凸部と半導体素子の熱膨張係数のミスマッチが減少し、半導体素子のクラックが改善される。また、凸部１５Ｂの間や窓部１９Ｂに接着剤や樹脂材料（充填材）を充填し、窓部に充填材を備えるものとすることで、モールドフロー及びトラックボイドの改善を図ることができる。 2 shows a cross-section of the upper insulating circuit board 10A in FIG. 1, and a top view of the lower insulating circuit board 10B in a state where no resin is filled and no semiconductor element is mounted. In the left diagram of FIG. 2, the upper insulating circuit board of the double-sided cooling power module is not shown for the sake of explanation. The right diagram of FIG. 2 is a plan view of the lower insulating circuit board in the left diagram in a state where no semiconductor element 1 is mounted and no filler material 20B is filled, as seen from above. As shown in FIG. 2, it is preferable to provide a window portion 19B that penetrates the wiring layer 14B to the surface of the resin film 11B around the convex portion 15B. The convex portion and the window portion can be formed by etching the copper-containing metal layer. If the etched area is filled with an adhesive or resin material, the effect of the difference in the thermal expansion coefficient of the copper-containing metal layer can be reduced. The mismatch between the thermal expansion coefficients of the convex portion and the semiconductor element is reduced, and cracks in the semiconductor element are improved. In addition, by filling the gaps between the protrusions 15B and the window portions 19B with adhesive or resin material (filler), and providing the window portions with filler, mold flow and track voids can be improved.
　図２の左図に示すような、回路部の、樹脂フィルム表面に設けられた銅含有金属からなる配線層１４Ｂ、凸部１５Ｂ、窓部１９Ｂの配置や形状は特に限定されない。 As shown in the left diagram of Figure 2, the arrangement and shape of the wiring layer 14B made of copper-containing metal provided on the surface of the resin film, the convex portion 15B, and the window portion 19B of the circuit portion are not particularly limited.
　接着剤や樹脂材料（充填材）には、Ａｌ２Ｏ３、ＢＮ、ＡＩＮなどのフィラーや、モールドレジン、ソルダーレジスト（ＰＳＲ：ｐｈｏｔｏｓｅｎｓｉｔｉｖｅ　ｓｏｌｄｅｒ　ｒｅｓｉｓｔ）、レジンフィル又はガラスエポキシ樹脂（ＦＲ４：Ｆｌａｍｅ　Ｒｅｔａｒｄａｎｔ　Ｔｙｐｅ　４）、はんだマスク、モールドコンパウンド、エポキシなどを含むことができる。特に、モールドレジン、ソルダーレジスト、レジンフィル又はガラスエポキシ樹脂を含むものが好ましい。 The adhesive or resin material (filler) may include fillers such as Al2O3 , BN, or AlN, mold resin, solder resist (PSR: photosensitive solder resist), resin fill, or glass epoxy resin (FR4: Flame Retardant Type 4), solder mask, mold compound, epoxy, etc. In particular, those containing mold resin, solder resist, resin fill, or glass epoxy resin are preferable.
　（半導体素子）
　本発明に係る両面冷却パワーモジュールに搭載される半導体素子１はパワー半導体素子であれば特に限定されない。例えば、炭化ケイ素（ＳｉＣ）や窒化ガリウム（ＧａＮ）のようなワイドバンドギャップ半導体を使用するワイドバンドギャップ半導体素子を用いることができる。このような半導体素子は、ソルダーペーストやＡｇペーストなどの接着層２１を介して、回路部の凸部上に設置される。 (Semiconductor element)
The semiconductor element 1 mounted on the double-sided cooling power module according to the present invention is not particularly limited as long as it is a power semiconductor element. For example, a wide band gap semiconductor element using a wide band gap semiconductor such as silicon carbide (SiC) or gallium nitride (GaN) can be used. Such a semiconductor element is installed on the convex portion of the circuit part via an adhesive layer 21 such as solder paste or Ag paste.
　上述のように、絶縁回路基板として、従来のセラミック基板とスペーサに代えて絶縁性の樹脂フィルムとを用いたものとすることで、高温信頼性が向上し、また、取扱いも容易となる。特に、従来のセラミック基板で問題となっていた高温でのクラックの発生を抑制することができる。さらに、半導体素子を搭載するときのスペーサを使用する必要がなく、材料の累積公差が小さくなるため、従来の両面冷却モジュールよりも平坦度管理に優れている。そして、材料コストを削減し、組立て工程を簡略化することが可能となる。 As described above, by using an insulating resin film instead of the conventional ceramic substrate and spacer as an insulating circuit board, high-temperature reliability is improved and handling is also easier. In particular, it is possible to suppress the occurrence of cracks at high temperatures, which was a problem with conventional ceramic substrates. Furthermore, there is no need to use spacers when mounting semiconductor elements, and the cumulative tolerance of materials is reduced, resulting in better flatness control than conventional double-sided cooling modules. It is also possible to reduce material costs and simplify the assembly process.
　次に、本発明に係る両面冷却パワーモジュールの放熱効果と評価結果について説明する。図４は、セラミック基板を用いた従来の両面冷却パワーモジュールと、本発明に係る両面冷却パワーモジュールとの放熱効果をシミュレーションにより評価・比較した結果を示す図である。この評価では、セラミック基板を用いた従来の両面冷却パワーモジュールと、樹脂フィルムを用いた本発明に係る両面冷却パワーモジュールについて、水冷ジャケットを装着して冷却を行い、高温状態となった時の温度特性をシミュレートして比較した。図４の温度分布のシミュレーション結果を示す図面において、上方１／３程度の領域の中心部付近の温度の高低を、色の濃淡で比較する。図４に示すように、本発明に係る両面冷却パワーモジュールは、温度上昇が低く抑えられており（色が薄い）、放熱効果が高いことがわかる。 Next, the heat dissipation effect and evaluation results of the double-sided cooling power module according to the present invention will be described. Figure 4 shows the results of a simulation evaluation and comparison of the heat dissipation effect of a conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention. In this evaluation, a water-cooled jacket was attached to cool the conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention using a resin film, and the temperature characteristics were simulated and compared when the module reached a high temperature state. In the diagram showing the simulation results of the temperature distribution in Figure 4, the temperature near the center of the upper 1/3 region is compared by the shade of color. As shown in Figure 4, the double-sided cooling power module according to the present invention has a low temperature rise (light color) and has a high heat dissipation effect.
　本発明に係る両面冷却パワーモジュールは、従来のセラミック基板を用いる場合のような、半導体素子を搭載するときのスペーサを用いていない。したがって、本発明に係る両面冷却パワーモジュールでは、半導体素子は絶縁回路基板に直接取り付けられており、スペーサを使用した場合よりも放熱効果が高い。このように、樹脂フィルムを用いたものはセラミック基板を用いたものより熱サイクル信頼性が高い。 The double-sided cooled power module of the present invention does not use spacers when mounting the semiconductor elements, as is the case when using conventional ceramic substrates. Therefore, in the double-sided cooled power module of the present invention, the semiconductor elements are directly attached to the insulating circuit substrate, and the heat dissipation effect is higher than when spacers are used. In this way, the one using the resin film has higher thermal cycle reliability than the one using the ceramic substrate.
　また、従来の両面冷却パワーモジュールでは、セラミック基板の厚さよりも、回路部や放熱部の銅含有金属からなる層の厚さを厚くすることはできなかった。その理由は、銅含有金属からなる層の厚さがセラミックの厚さよりも厚いと、セラミックのクラックが発生しやすくなるためである。一方、樹脂フィルムは回路部や放熱部の銅含有金属からなる層の厚さを厚くすることが可能であり、これにより、放熱をさらに促進し、電力を増加させ、クラックの発生をより効果的に抑制することが可能である。 Furthermore, in conventional double-sided cooled power modules, the thickness of the copper-containing metal layer in the circuit section and heat dissipation section could not be made thicker than the ceramic substrate. This is because if the copper-containing metal layer is thicker than the ceramic, the ceramic is more likely to crack. On the other hand, resin film makes it possible to make the copper-containing metal layer in the circuit section and heat dissipation section thicker, which further promotes heat dissipation, increases power, and more effectively suppresses the occurrence of cracks.
　図５は、セラミック基板を用いた従来の両面冷却パワーモジュールと本発明に係る両面冷却パワーモジュールについて、サイズ（特に厚さ）の評価・比較を示す図である。半導体素子（Ｄｉｅ：ダイ）など、両者に共通するものは同等のものとする前提として評価を行った。各層にはそれぞれ製作上の公差があるため、層の数が増えるに従い、全体の厚さが大きくなるとともに累積公差も増大する。図５に示すように、従来の両面冷却パワーモジュールではパッケージ全体の厚さが０．２４～０．２６ｍｍ程度の範囲でばらつくこととなる。複数の半導体素子の部分でこのようなばらつきが生じると、パワーモジュール全体の厚さにもばらつきが生じ、平坦度が悪化する。これに対し、本発明に係る両面冷却パワーモジュールではパッケージ全体の厚さが０．２２ｍｍ程度となる。このように、本発明に係る両面冷却パワーモジュールでは管理すべき材料の数が少なく、したがって、寸法精度が向上し、全体の厚さや平坦度の管理が容易になることがわかる。その結果、ウォータージャケットなどのヒートシンクとの間に隙間ができず、接触性が向上し、熱性能の向上が期待できる。 Figure 5 shows an evaluation and comparison of the size (particularly thickness) of a conventional double-sided cooling power module using a ceramic substrate and a double-sided cooling power module according to the present invention. The evaluation was performed on the premise that the semiconductor elements (Dies) and other elements common to both are equivalent. Since each layer has its own manufacturing tolerance, as the number of layers increases, the overall thickness increases and the cumulative tolerance also increases. As shown in Figure 5, in the conventional double-sided cooling power module, the thickness of the entire package varies within a range of about 0.24 to 0.26 mm. If such variation occurs in the multiple semiconductor elements, the thickness of the entire power module also varies, and the flatness deteriorates. In contrast, in the double-sided cooling power module according to the present invention, the thickness of the entire package is about 0.22 mm. As such, it can be seen that the double-sided cooling power module according to the present invention requires fewer materials to be managed, and therefore the dimensional accuracy is improved, and the overall thickness and flatness can be easily managed. As a result, no gap is formed between the heat sink such as a water jacket, contact is improved, and thermal performance can be expected to be improved.
　図６は、セラミック基板を用いた従来の両面冷却パワーモジュールと本発明に係る両面冷却パワーモジュールの、組立て工程（概略）の比較を示す図である。本発明に係る両面冷却パワーモジュールの組立て工程では、スペーサに半導体素子を搭載するプロセスを省略できる。そのため、従来の方法に比べて組立て工程が簡略化されることがわかる。さらに、スペーサ、接着剤（はんだ、エポキシ、銀ペーストなど）の使用量削減に伴うコストダウンや、工程の簡素化による、ＵＰＨ（Ｕｎｉｔ　Ｐｅｒ　Ｈｏｕｒ：１時間当たりで実行可能な搭載部品の総数）を増加させることが可能となる。 Figure 6 is a diagram showing a comparison of the assembly process (outline) of a conventional double-sided cooled power module using a ceramic substrate and a double-sided cooled power module according to the present invention. In the assembly process of the double-sided cooled power module according to the present invention, the process of mounting semiconductor elements on spacers can be omitted. Therefore, it can be seen that the assembly process is simplified compared to the conventional method. Furthermore, it is possible to reduce costs by reducing the amount of spacers and adhesives (solder, epoxy, silver paste, etc.) used, and to increase UPH (Units Per Hour: the total number of mounted parts that can be mounted per hour) by simplifying the process.
　次に、熱特性についてのシミュレーションを行った結果について説明する。図７は、熱特性についてのシミュレーション結果を示す図である。セラミック基板を用いたとき（従来例）のジャンクション温度を基準値とし、樹脂フィルムの膜厚をシミュレーション上のパラメータとした。図７からわかるように、樹脂フィルムの膜厚は、高熱でより良い性能を示すために１６０μｍ未満の範囲とすると、放熱特性により優れ、より安定して従来のものよりもジャンクション温度を低くすることができることがわかる。なお、樹脂フィルムの膜厚は、高温特性を向上するためにフィルムに含有させるフィラーの大きさや、フィルムの強度、安定性の観点から、４０μｍ以上とすることが好ましい。 Next, the results of a simulation of thermal characteristics will be explained. Figure 7 shows the results of the simulation of thermal characteristics. The junction temperature when a ceramic substrate is used (conventional example) was used as the reference value, and the film thickness of the resin film was used as a parameter in the simulation. As can be seen from Figure 7, if the film thickness of the resin film is set to a range of less than 160 μm to show better performance at high heat, it is possible to achieve a lower junction temperature with better heat dissipation characteristics and more stable performance than conventional films. It is preferable that the film thickness of the resin film is 40 μm or more from the viewpoints of the size of the filler contained in the film to improve high-temperature characteristics, the strength of the film, and stability.
　以上説明した本発明に係る両面冷却パワーモジュールの利点を、従来技術と対比しながら図８にまとめた。図８の「Ｔｙｐｅ＃１」は、図３を用いて説明した従来の両面冷却パワーモジュールであり、例えば特許文献２に記載されるものである。図８の「Ｔｙｐｅ＃２」は、セラミック基板の表面に印刷法によりＣｕ層を形成（ＴＰＣ法：Ｔｈｉｃｋ　Ｐｒｉｎｔ　Ｃｏｐｐｅｒ法）した絶縁回路基板を用いた従来の両面冷却パワーモジュールであり、例えば特許文献３に記載されるものである。これらを比較すると明らかなように、本発明に係る両面冷却パワーモジュールは、従来問題となっていた高温環境での割れなどの破損を抑制でき、表面の平坦性の制御が容易であり、モールドボイドなどの構造上の問題も抑制可能なものであり、高温でも信頼度の高いものである。 Advantages of the double-sided cooling power module according to the present invention described above are summarized in FIG. 8 in comparison with the conventional technology. "Type #1" in FIG. 8 is the conventional double-sided cooling power module described using FIG. 3, and is described in, for example, Patent Document 2. "Type #2" in FIG. 8 is a conventional double-sided cooling power module using an insulating circuit board in which a Cu layer is formed on the surface of a ceramic substrate by a printing method (TPC method: Thick Print Copper method), and is described in, for example, Patent Document 3. As is clear from comparing these, the double-sided cooling power module according to the present invention can suppress damage such as cracks in high-temperature environments, which was a conventional problem, can easily control the flatness of the surface, can suppress structural problems such as mold voids, and is highly reliable even at high temperatures.
　なお、本発明は、上記実施形態に限定されるものではない。上記実施形態は例示であり、本発明の特許請求の範囲に記載された技術的思想と実質的に同一な構成を有し、同様な作用効果を奏するものは、いかなるものであっても本発明の技術的範囲に包含される。 The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and provides similar effects is included within the technical scope of the present invention.

Claims (5)

  1. 　半導体素子と、該半導体素子を挟持する２つの絶縁回路基板を備えた両面冷却パワーモジュールであって、
    　前記２つの絶縁回路基板は、それぞれ、絶縁性の樹脂フィルムと、該樹脂フィルムの前記半導体素子側に設けられた回路部と、前記樹脂フィルムの前記半導体素子とは反対側に設けられた放熱部とを備え、
    　前記回路部は、前記樹脂フィルム表面に設けられた銅含有金属からなる配線層と、該配線層から前記半導体素子側に向けて突出して前記半導体素子を支持する銅含有金属からなる凸部を備え、
    　前記放熱部は、前記樹脂フィルム表面に設けられた銅含有金属層を備えるものであることを特徴とする両面冷却パワーモジュール。     A double-sided cooled power module including a semiconductor element and two insulating circuit boards that sandwich the semiconductor element,
    each of the two insulating circuit boards includes an insulating resin film, a circuit portion provided on the semiconductor element side of the resin film, and a heat dissipation portion provided on the resin film on the opposite side to the semiconductor element;
    the circuit section includes a wiring layer made of a copper-containing metal provided on a surface of the resin film, and a protrusion made of a copper-containing metal protruding from the wiring layer toward the semiconductor element and supporting the semiconductor element;
    13. A double-sided cooling power module, wherein the heat dissipation portion comprises a copper-containing metal layer provided on a surface of the resin film.
  2. 　前記回路部における前記配線層の銅含有金属と前記凸部の銅含有金属は、異なる材料からなるものであることを特徴とする請求項１に記載の両面冷却パワーモジュール。 The double-sided cooling power module of claim 1, characterized in that the copper-containing metal of the wiring layer in the circuit section and the copper-containing metal of the protrusions are made of different materials.
  3. 　前記絶縁回路基板は、前記回路部の前記凸部が設けられていない前記配線層上に、モールドレジン、ソルダーレジスト、レジンフィル又はガラスエポキシ樹脂を含む充填材を備えるものであることを特徴とする請求項１又は２に記載の両面冷却パワーモジュール。 The double-sided cooling power module according to claim 1 or 2, characterized in that the insulating circuit board is provided with a filler containing mold resin, solder resist, resin fill or glass epoxy resin on the wiring layer where the protrusion of the circuit part is not provided.
  4. 　前記絶縁回路基板は、前記回路部の前記凸部の周囲に、前記樹脂フィルムの表面まで前記配線層を貫通する窓部を備え、前記窓部に充填材を備えるものであることを特徴とする請求項１から３のいずれか一項に記載の両面冷却パワーモジュール。 The double-sided cooling power module according to any one of claims 1 to 3, characterized in that the insulating circuit board has a window portion around the protruding portion of the circuit portion, which penetrates the wiring layer to the surface of the resin film, and the window portion is provided with a filler.
  5. 　前記絶縁回路基板の前記樹脂フィルムの厚さは４０μｍ以上、１６０μｍ未満であることを特徴とする請求項１から４のいずれか一項に記載の両面冷却パワーモジュール。 The double-sided cooling power module according to any one of claims 1 to 4, characterized in that the thickness of the resin film of the insulating circuit board is 40 μm or more and less than 160 μm.
PCT/JP2022/042109 2022-11-11 2022-11-11 Dual-side cooled power module WO2024100894A1 (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08250823A (en) * 1995-03-10 1996-09-27 Toshiba Corp Ceramic circuit board
US6638592B1 (en) * 1999-06-14 2003-10-28 Jurgen Schulz-Harder Ceramic/metal substrate, especially composite substrate
JP2010258315A (en) * 2009-04-28 2010-11-11 Hitachi Automotive Systems Ltd Power module and power converter
WO2011093373A1 (en) * 2010-01-27 2011-08-04 京セラ株式会社 Complex and semiconductor device using the same, semiconductor module and method for fabricating the same
JP2016054175A (en) * 2014-09-03 2016-04-14 トヨタ自動車株式会社 Semiconductor device
JP2016134601A (en) * 2015-01-22 2016-07-25 トヨタ自動車株式会社 Semiconductor device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08250823A (en) * 1995-03-10 1996-09-27 Toshiba Corp Ceramic circuit board
US6638592B1 (en) * 1999-06-14 2003-10-28 Jurgen Schulz-Harder Ceramic/metal substrate, especially composite substrate
JP2010258315A (en) * 2009-04-28 2010-11-11 Hitachi Automotive Systems Ltd Power module and power converter
WO2011093373A1 (en) * 2010-01-27 2011-08-04 京セラ株式会社 Complex and semiconductor device using the same, semiconductor module and method for fabricating the same
JP2016054175A (en) * 2014-09-03 2016-04-14 トヨタ自動車株式会社 Semiconductor device
JP2016134601A (en) * 2015-01-22 2016-07-25 トヨタ自動車株式会社 Semiconductor device

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