JP4606685B2 - Module with built-in circuit components - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a module incorporating a circuit component, which has high density, can mount the circuit component and has high reliability, by using an electric insulating substrate formed of mixture including inorganic filler and thermosetting resin and to provide the manufacturing method. SOLUTION: The module includes the electric insulating substrate 101 formed of mixture including 70 to 95 weight % of inorganic filler and thermosetting resin, a first wiring pattern 102b formed on one main face of the electric insulating substrate 101, a second wiring pattern 102a formed on the other main face of the electric insulating substrate 101, at least one circuit part 103b which is buried in the electric insulating substrate 101 and is electrically connected to the first wiring pattern 102b and an inner via 104 formed in the electric insulating substrate 101 so that it electrically connects the first wiring pattern 102b and the second wiring pattern 102a.

Description

【００９９】
この実施例では、液状エポキシ樹脂には、日本ペルノックス（株）製のエポキシ樹脂（ＷＥ−２０２５、酸無水系硬化剤含む）を用いた。フェノール樹脂には、大日本インキ（株）製のフェノール樹脂（フェノライト、ＶＨ４１５０）を用いた。シアネート樹脂には、旭チバ（株）製のシアネート樹脂（ＡｒｏＣｙ、Ｍ−３０）を用いた。この実施例では、添加物としてカーボンブラックまたは分散剤を加えた。
【０１００】
板状体の作製は、まず、表１の組成で混合されたペースト状の混合物を、所定量だけ離型フィルム上に滴下する。ペースト状の混合物は、無機フィラーと液状の熱硬化性樹脂とを攪拌混合機によって１０分程度混合して作製した。使用した攪拌混合機は、所定の容量の容器に無機フィラーと液状の熱硬化性樹脂とを投入し、容器自身を回転させながら公転させるもので、混合物の粘度が比較的高くても充分な分散状態が得られる。離型フィルムには厚み７５μｍのポリエチレンテレフタレートフィルムを用い、フィルム表面にシリコンによる離型処理を施した。
【０１０１】
次に、離型フィルム上のペースト状の混合物にさらに離型フィルムを重ね、加圧プレスで厚さ５００μｍになるようにプレスして、板状の混合物を得た。
【０１０２】
次に、離型フィルムで挟まれた板状の混合物を離型フィルムごと加熱し、板状の混合物の粘着性が無くなる条件下で熱処理した。熱処理は、１２０℃の温度で１５分間保持である。この熱処理によって、板状の混合物の粘着性が失われるため、離型フィルムの剥離が容易になる。この実施例で用いた液状エポキシ樹脂は、硬化温度が１３０℃であるため、この熱処理条件下では、未硬化状態（Ｂステージ）である。
【０１０３】
次に、板状の混合物から離型フィルムを剥離し、板状の混合物を耐熱性離型フィルム（ＰＰＳ：ポリフェニレンサルファイト、厚さ７５μｍ）で挟んで、５０ｋｇ／ｃｍ²の圧力で加圧しながら１７０℃の温度で加熱することによって板状の混合物を硬化させた。
【０１０４】
次に、硬化した板状の混合物から耐熱性離型フィルムを剥離することによって、電気絶縁性基板を得た。
【０１０５】
この電気絶縁性基板を所定の寸法に加工して、熱伝導度、線膨張係数などを測定した。熱伝導度は、１０ｍｍ角に切断した試料の表面を加熱ヒータに接触させて加熱し、反対面の温度上昇から計算で求めた。線膨張係数は、室温から１４０℃まで温度上昇させた場合の電気絶縁性基板の寸法変化を測定し、その寸法変化の平均値から求めた。絶縁耐圧は、電気絶縁性基板の厚み方向にＡＣ電圧を印加した場合の絶縁耐圧を求め、単位厚み当たりの絶縁耐圧を計算した。
【０１０６】
表１に示すように、上記の方法で作製された電気絶縁性基板は、無機フィラーとしてＡｌ₂Ｏ₃を用いた場合には、従来のガラス−エポキシ基板（熱伝導度０．２ｗ／ｍＫ〜０．３ｗ／ｍＫ）に比べて熱伝導度が約１０倍以上となった。Ａｌ₂Ｏ₃の量を８５重量％以上とすることによって、熱伝導度を２．８ｗ／ｍＫ以上とすることができた。Ａｌ₂Ｏ₃はコストが安いという利点もある。
【０１０７】
また、無機フィラーとしてＡｌＮ、ＭｇＯを用いた場合では、Ａｌ₂Ｏ₃を用いた場合と同等以上の熱伝導度が得られた。
【０１０８】
また、無機フィラーとして非晶質ＳｉＯ₂を用いた場合では、線膨張係数がシリコン半導体（線膨張係数３×１０^-6／℃）により近くなった。したがって、無機フィラーとして非晶質ＳｉＯ₂を用いた電気絶縁性基板は、半導体を直接実装するフリップチップ用基板として好ましい。
【０１０９】
また、無機フィラーとしてＳｉＯ₂を用いた場合には、誘電率が低い電気絶縁性基板が得られた。ＳｉＯ₂は比重が軽いという利点もある。無機フィラーとしてＳｉＯ₂を用いた回路部品内蔵モジュールは、携帯電話などの高周波用モジュールとして好ましい。
【０１１０】
また、無機フィラーとしてＢＮを用いた場合には、熱伝導度が高く線膨張係数が低い電気絶縁性基板が得られた。
【０１１１】
表１の比較例（試料番号１）に示すように、無機フィラーとして６０重量％のＡｌ₂Ｏ₃を用いた場合を除いて、電気絶縁性基板の絶縁耐圧は、１０ｋＶ／ｍｍ以上であった。電気絶縁性基板の絶縁耐圧は、電気絶縁性基板の材料である無機フィラーと熱硬化性樹脂との接着性の指標となる。すなわち、無機フィラーと熱硬化性樹脂との接着性が悪いと、その間に微小な隙間が生じて絶縁耐圧が低下する。このような微小な隙間は回路部品内蔵モジュールの信頼性低下を招く。一般に、絶縁耐圧が１０ｋＶ／ｍｍ以上であれば無機フィラーと熱硬化性樹脂との接着性が良好であると判断できる。したがって、無機フィラーの量は７０重量％以上であることが好ましい。
【０１１２】
なお、熱硬化性樹脂の含有量が低いと電気絶縁性基板の強度が低下するため、熱硬化性樹脂は４．８重量％以上であることが好ましい。
【０１１３】
（実施例２）
実施例２は、実施形態２で説明した方法で回路部品内蔵モジュールを作製した一例である。
【０１１４】
本実施例に使用した電気絶縁性基板の組成は、Ａｌ₂Ｏ₃（昭和電工（株）製ＡＳ−４０、球状、平均粒子径１２μｍ）が９０重量％、液状エポキシ樹脂（日本レック（株）製、ＥＦ−４５０）が９．５重量％、カーボンブラック（東洋カーボン（株）製）が０．２重量％、カップリング剤（味の素（株）製、チタネート系、４６Ｂ）が０．３重量％である。
【０１１５】
上記材料を実施例１と同様の条件で処理することによって、板状体（厚み５００μｍ）を作製した。上記板状体を所定の大きさに切断し、炭酸ガスレーザを用いてインナービアホール接続をするための貫通孔（直径０．１５ｍｍ）を形成した（図２（ｂ）参照）。
【０１１６】
この貫通孔に、導電性樹脂組成物をスクリーン印刷法によって充填した（図２（ｃ）参照）。導電性樹脂組成物は、球状の銅粒子８５重量％と、ビスフェノールＡ型エポキシ樹脂（油化シェルエポキシ製、エピコート８２８）３重量％と、グルシジルエステル系エポキシ樹脂（東都化成製、ＹＤ−１７１）９重量％と、アミンアダクト硬化剤（味の素製、ＭＹ−２４）３重量％とを混練して作製した。
【０１１７】
次に、厚さ３５μｍの銅箔の片面を粗化し、粗化した面に導電性接着剤を用いて半導体素子をフリップチップボンディングした（図２（ｄ）参照）。
【０１１８】
次に、半導体素子を実装した銅箔と、導電性樹脂組成物を充填した板状体と、別途作製した銅箔（片面を粗化処理した銅箔で厚さ３５μｍ）とを位置合わせして重ねた（図２（ｆ）参照）。この時、銅箔の粗化面は、板状体側になるように重ねた。
【０１１９】
次に、これを熱プレス機によってプレス温度１２０℃、圧力１０ｋｇ／ｃｍ²で５分間加熱加圧した。硬化温度より低い温度での加熱によって、板状体中の熱硬化性樹脂が軟化するため、半導体素子が板状体中に容易に埋没した。
【０１２０】
次に、加熱温度を上昇させて１７５℃で６０分間加熱した（図２（ｇ）参照）。この加熱によって、板状体中のエポキシ樹脂および導電性樹脂組成物中のエポキシ樹脂が硬化し、半導体素子および銅箔と板状体とが機械的に強固に接続された。また、この加熱によって、導電性樹脂組成物と銅箔とが電気的（インナービア接続）、機械的に接続された。
【０１２１】
次に、半導体素子が埋設された板状体の表面の銅箔を、フォトリソ工程およびエッチング工程によってエッチングし、配線パターンを形成した（図２（ｈ）参照）。このようにして、回路部品内蔵モジュールを作成した。
【０１２２】
本実施例によって作製された回路部品内蔵モジュールの信頼性を評価するため、半田リフロー試験および温度サイクル試験を行った。半田リフロー試験は、ベルト式リフロー試験機を用い、最高温度が２６０℃で１０秒のサイクルを１０回繰り返すことで行った。温度サイクル試験は、１２５℃で３０分間保持した後、−６０℃の温度で３０分間保持する工程を２００サイクル繰り返すことによって行った。
【０１２３】
半田リフロー試験および温度サイクル試験のいずれにおいても、本実施例の回路部品内蔵モジュールにはクラックが発生せず、超音波探傷装置を用いても特に異常は認められなかった。この試験から、半導体素子と電気絶縁性基板とは、強固に接着していることがわかる。また、導電性樹脂組成物によるインナービア接続の抵抗値も、試験開始前後でほとんど変化がなかった。
【０１２４】
（実施例３）
実施例３は、実施形態３で説明した方法で回路部品内蔵モジュールを作製した一例である。
【０１２５】
まず、実施例２と同様の方法で、貫通孔に導電性樹脂組成物が充填された板状体（厚さ５００μｍ）を作製した（図３（ｃ）参照）。
【０１２６】
次に、離型フィルム（ポリフェニレンサルファイト製、厚さ１５０μｍ）に、厚さ３５μｍの銅箔を接着剤によって接着した。この銅箔は、片面が粗化処理されており、光沢面が接着剤側になるように接着した。
【０１２７】
次に、離型フィルム上の銅箔を、フォトリソ工程およびエッチング工程によってエッチングして、配線パターンを形成した。さらにこの配線パターン上に、半田バンプを用いて半導体素子をフリップチップボンディングした（図３（ｄ）参照）。
【０１２８】
次に、配線パターンに実装した半導体素子と配線パターンとの隙間に封止樹脂を注入した。具体的には、７０℃に加熱したホットプレートを傾け、そのホットプレート上に、半導体素子を実装した配線パターンを有する離型フィルムを設置した後、半導体素子と配線パターンとの間に注射器で徐々に封止樹脂を注入した。１０秒程度で半導体素子と配線パターンとの間に封止樹脂を注入できた。ホットプレートで加熱するのは、封止樹脂の粘度を下げて短時間に注入できるようにするためである。また、ホットプレートを傾けるのは注入を容易にするためである。封止樹脂には、テクノアルファー（株）製ＥＬ１８Ｂを用いた。ＥＬ１８Ｂは、一液性のエポキシ樹脂にＳｉＯ₂粉末を混入した樹脂である。
【０１２９】
一方、上記工程と平行して、上記工程と同様に、片面に配線パターンが形成された離型フィルム（ポリフェニレンサルファイト製、厚さ１５０μｍ）を作製した（図３（ｅ）参照）。
【０１３０】
次に、半導体素子をボンディングした離型フィルムと、貫通孔に導電性樹脂組成物が充填された板状体と、片面に配線パターンが形成された離型フィルムとを、位置合わせして重ねた（図３（ｆ）参照）。
【０１３１】
次に、これを熱プレス機によってプレス温度１２０℃、圧力１０ｋｇ／ｃｍ²で５分間加熱加圧した。硬化温度より低い温度での加熱によって、板状体中の熱硬化性樹脂が軟化するため、半導体素子および配線パターンが板状体中に容易に埋没した。
【０１３２】
次に、加熱温度を上昇させて１７５℃で６０分間加熱した（図３（ｇ）参照）。この加熱によって、板状体および導電性樹脂組成物中のエポキシ樹脂が硬化するため、半導体素子および配線パターンと板状体とが機械的に強固に接続された。また、この加熱によって、導電性樹脂組成物と配線パターンとが電気的（インナービア接続）、機械的に接続された。さらに、この加熱によって、半導体素子と配線パターンとの間に注入された封止樹脂も硬化した。
【０１３３】
次に、板状体から離型フィルムを剥離した（図３（ｈ）参照）。ポリフェニレンサルファイト製の離型フィルムは、上記加熱温度以上の耐熱性がある。また、銅箔の粗化された面は板状体およびインナービアと接着し、銅箔の光沢面は離型フィルムと接着している。したがって、板状体およびインナービアと銅箔との接着強度は、離型フィルムと銅箔との接着強度よりも大きいため、離型フィルムだけを剥離することができる。このようにして、回路部品内蔵モジュールを作成した。
【０１３４】
実施例３によって作製された回路部品内蔵モジュールの信頼性を評価するため、実施例２と同様の条件で、半田リフロー試験および温度サイクル試験を行った。
【０１３５】
半田リフロー試験および温度サイクル試験のいずれにおいても、実施例３の回路部品内蔵モジュールにはクラックが発生せず、超音波探傷装置を用いても特に異常は認められなかった。この試験から、半導体素子と電気絶縁性基板とは、強固に接着していることがわかる。また、導電性樹脂組成物によるインナービア接続の抵抗値も、試験開始前後でほとんど変化がなかった。
【０１３６】
（実施例４）
この実施例４は、実施形態５で説明した方法で多層構造を有する回路部品内蔵モジュールを作製した一例である。
【０１３７】
この実施例４では、回路部品として、半導体素子とチップ部品とを用いた。
【０１３８】
まず、実施例２と同様の方法で、貫通孔に導電性樹脂組成物が充填された板状体を形成した。
【０１３９】
次に、貫通孔に導電性樹脂組成物が充填された板状体と、回路部品がフリップチップボンディングされた配線パターンを備える離型フィルム（ポリフェニレンサルファイト製）とを、位置合わせして重ねた（図５（ａ）参照）。
【０１４０】
次に、これを熱プレス機によって、プレス温度１２０℃、圧力１０ｋｇ／ｃｍ²で５分間加熱加圧した。硬化温度より低い温度での加熱によって、板状体中の熱硬化性樹脂が軟化するため、回路部品が板状体中に容易に埋没した。そして、離型フィルムを板状体から剥離することによって回路部品が埋設された板状体を形成した（図５（ｂ）参照）。
【０１４１】
この板状体を複数個作製し、複数個の板状体と銅箔とを位置合わせして重ねた（図５（ｇ）参照）。
【０１４２】
次に、これを熱プレス機によって、プレス温度１７５℃、圧力５０ｋｇ／ｃｍ²で６０分間加熱加圧した。この加熱加圧処理によって、回路部品が埋設された複数の板状体と銅箔とが一体となって、一つの板状体が形成された。この加熱加圧処理によって、板状体および導電性樹脂組成物中のエポキシ樹脂が硬化し、回路部品および配線パターンと板状体とが機械的に強固に接続された。また、この加熱加圧処理によって、銅箔および配線パターンと導電性樹脂組成物とが電気的（インナービア接続）、機械的に接続された。
【０１４３】
次に、回路部品が埋設された板状体の表面の銅箔を、フォトリソ工程およびエッチング工程によってエッチングすることによって、配線パターンを形成した（図５（ｈ）参照）。このようにして、多層構造を有する回路部品内蔵モジュールを作製した。
【０１４４】
実施例４によって作製された回路部品内蔵モジュールの信頼性を評価するため、実施例２と同様の条件で、半田リフロー試験および温度サイクル試験を行った。
【０１４５】
半田リフロー試験および温度サイクル試験のいずれにおいても、実施例４の回路部品内蔵モジュールにはクラックが発生せず、超音波探傷装置を用いても特に異常は認められなかった。この試験から、半導体素子と電気絶縁性基板とは、強固に接着していることがわかる。また、導電性樹脂組成物によるインナービア接続の抵抗値も、試験開始前後でほとんど変化がなかった。
【０１４６】
（実施例５）
この実施例５は、実施形態６で説明した方法で多層構造を有する回路部品内蔵モジュールを作製した一例である。
【０１４７】
まず、実施例２と同様の方法で、貫通孔に導電性樹脂組成物が充填された板状体を形成した。次に、貫通孔に導電性樹脂組成物が充填された板状体と、回路部品がフリップチップボンディングされた配線パターンを備える離型フィルム（ポリフェニレンサルファイト製）とを、位置合わせして重ねた（図６（ａ）参照）。
【０１４８】
次に、これを熱プレス機によって、プレス温度１２０℃、圧力１０ｋｇ／ｃｍ²で５分間加熱加圧した。硬化温度より低い温度での加熱によって、板状体中の熱硬化性樹脂が軟化するため、回路部品が板状体中に容易に埋没した。そして、離型フィルムを板状体から剥離することによって板状体を形成した（図６（ｂ）参照）。同様に、回路部品が埋設された板状体を形成した（図６（ｄ）参照）。
【０１４９】
次に、離型フィルム（ポリフェニレンサルファイト製）の片面に配線パターンを形成した（図６（ｅ）参照）。
【０１５０】
次に、回路部品が埋設された２個の板状体と、配線パターンが形成された離型フィルムとを位置合わせして重ねた（図６（ｆ）参照）。
【０１５１】
次に、これを熱プレス機によって、プレス温度１７５℃、圧力５０ｋｇ／ｃｍ²で６０分間加熱加圧した。この加熱加圧処理によって、回路部品が埋設された複数の板状体と離型フィルムとが一体となって、一つの板状体が形成された。この加熱加圧処理によって、板状体中のエポキシ樹脂が硬化し、回路部品および配線パターンと板状体とが機械的に強固に接続された。また、この加熱加圧処理によって導電性樹脂組成物中のエポキシ樹脂が硬化し、配線パターンと導電性樹脂組成物とが電気的（インナービア接続）、機械的に接続された。
【０１５２】
次に、一体となった板状体から離型フィルムを剥離することによって、多層構造を有する回路部品内蔵モジュールを作製した（図６（ｇ）参照）。
【０１５３】
実施例５によって作製された回路部品内蔵モジュールの信頼性を評価するため、実施例２と同様の条件で、半田リフロー試験および温度サイクル試験を行った。
【０１５４】
半田リフロー試験および温度サイクル試験のいずれにおいても、実施例５の回路部品内蔵モジュールにはクラックが発生せず、超音波探傷装置を用いても特に異常は認められなかった。この試験から、半導体素子と電気絶縁性基板とは、強固に接着していることがわかる。また、導電性樹脂組成物によるインナービア接続の抵抗値も、試験開始前後でほとんど変化がなかった。
【０１５５】
【発明の効果】
以上説明したように、本発明の回路部品内蔵モジュールでは、無機フィラーと熱硬化性樹脂との混合物からなる電気絶縁性基板を用いているため、放熱性が高い回路部品内蔵モジュールが得られる。
【０１５６】
また、本発明の回路部品内蔵モジュールでは、多層構造とすることによって、さらに高密度に回路部品が実装することができる。
【０１５７】
さらに、本発明の回路部品内蔵モジュールでは、無機フィラーを選択することによって、電気絶縁性基板の熱伝導度、線膨張係数、誘電率などを制御することが可能である。したがって、本発明の回路部品内蔵モジュールでは、電気絶縁性基板の線膨張係数を半導体素子とほぼ同じにすることが可能であるため、半導体素子を内蔵した回路部品内蔵モジュールとして好ましい。また、電気絶縁性基板の熱伝導度を向上させることができるため、放熱を必要とする半導体素子などを内蔵した回路部品内蔵モジュールとして好ましい。さらに、電気絶縁性基板の誘電率を低くすることもできるため、高周波回路用の回路部品内蔵モジュールとして好ましい。
【０１５８】
本発明の回路部品内蔵モジュールの製造方法では、上記回路部品内蔵モジュールを容易に製造することができる。
【０１５９】
また、本発明の回路部品内蔵モジュールの製造方法では、配線パターンを形成した離型フィルムを用いることによって、配線パターンを電気絶縁性基板に埋設することができるため、表面が平滑な回路部品内蔵モジュールが得られる。したがって、表面の配線パターンにさらに回路部品を実装する場合に、高密度で回路部品を実装することができる。
【図面の簡単な説明】
【図１】 本発明の回路部品内蔵モジュールの一実施形態を示す斜視断面図である。
【図２】 本発明の回路部品内蔵モジュールの製造方法の一実施形態を示す工程図である。
【図３】 本発明の回路部品内蔵モジュールの製造方法の他の一実施形態を示す工程図である。
【図４】 本発明の回路部品内蔵モジュールの他の一実施形態を示す斜視断面図である。
【図５】 本発明の回路部品内蔵モジュールの製造方法の他の一実施形態を示す工程図である。
【図６】 本発明の回路部品内蔵モジュールの製造方法の他の一実施形態を示す工程図である。
【符号の説明】
１００、４００ 回路部品内蔵モジュール
１０１、４０１、４０１ａ、４０１ｂ、４０１ｃ 電気絶縁性基板
１０２ａ、１０２ｂ、４０２ａ、４０２ｂ、４０２ｃ、４０２ｄ 配線パターン
１０３、４０３ 回路部品
１０３ａ、４０３ａ 能動部品
１０３ｂ、４０３ｂ 受動部品
１０４、４０４ インナービア[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a circuit component built-in module, and more particularly to a circuit component built-in module in which a circuit component is disposed inside an electrically insulating substrate.
[0002]
[Prior art]
In recent years, with the demand for higher performance and smaller size of electronic devices, higher density and higher functionality of circuit components have been screamed. For this reason, there is a demand for a circuit board corresponding to high density and high functionality of circuit components.
[0003]
As a method of increasing the density of circuit components, a method of multilayering a circuit is conceivable. However, in conventional glass-epoxy substrates, it is necessary to use a through-hole structure with a drill, so it is possible to cope with high-density mounting. Have difficulty. For this reason, the development of an inner via hole connection method capable of connecting wiring patterns between LSIs and components at the shortest distance is being developed in various directions as a method capable of achieving the highest circuit density.
[0004]
In the inner via hole connection method, it is possible to connect only necessary layers, and the circuit component is excellent in mountability (Japanese Patent Laid-Open Nos. 63-47991 and 6-268345).
[0005]
[Problems to be solved by the invention]
However, conventionally, the substrate used in the inner via hole connection method has been composed of a resin-based material, and thus has a problem of low thermal conductivity. In the circuit component built-in module, the higher the mounting density of the circuit components, the higher the need to dissipate the heat generated from the component. There was a problem that the reliability of the system deteriorated.
[0006]
In order to solve the above-described conventional problems, the present invention is capable of mounting circuit components with high density and having high reliability. Le The purpose is to provide.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a circuit component built-in module according to the present invention includes an electrically insulating substrate made of a mixture containing 70% to 95% by weight of an inorganic filler and a thermosetting resin, and one of the electrically insulating substrates. A first wiring pattern formed on the main surface of the first insulating layer, a second wiring pattern formed on the other main surface of the electrically insulating substrate, and the first wiring pattern embedded in the electrically insulating substrate. At least one circuit component electrically connected, and an inner via formed in the electrically insulating substrate so as to electrically connect the first wiring pattern and the second wiring pattern. The first wiring pattern is embedded in the electrically insulating substrate and the surface is flat, and the circuit component is embedded in the electrically insulating substrate, and the first wiring pattern by the inner via and the Electrical connection with the second wiring pattern is performed simultaneously. . In this circuit component built-in module, heat generated from the circuit component is quickly dissipated by the inorganic filler, so that a highly reliable circuit component built-in module can be obtained. Furthermore, by selecting an inorganic filler, the thermal conductivity, linear expansion coefficient, dielectric constant, dielectric strength, etc. of the electrically insulating substrate can be changed according to the built-in circuit components. Further, in a circuit component built-in module including a semiconductor element and a chip capacitor, it is possible to reduce electrical signal noise by shortening the distance between the semiconductor element and the chip capacitor.
[0008]
In the circuit component built-in module, it is preferable that at least two types of circuit components are embedded in the electrically insulating substrate.
[0009]
In the circuit component built-in module, the circuit component preferably includes a semiconductor bare chip.
[0010]
In the circuit component built-in module, it is preferable that the circuit component includes at least one component selected from a chip-shaped resistor, a chip-shaped capacitor, and a chip-shaped inductor. By using a chip-like component, it can be easily embedded in the electrically insulating substrate.
[0011]
In the circuit component built-in module, the semiconductor bare chip is preferably flip-chip bonded to the first wiring pattern.
[0012]
In the circuit component built-in module, the inner via is preferably made of a conductive resin composition. In the case where the inner via is made of a conductive resin composition, the manufacture becomes easy.
[0013]
In the circuit component built-in module, it is preferable that the wiring pattern includes a conductive resin composition. By using the conductive resin composition, the wiring pattern can be easily formed.
[0014]
In the circuit component built-in module, it is preferable that the wiring pattern comprises a metal plate lead frame formed by an etching method or a punching method. This is because the metal plate lead frame has low electrical resistance. By using the etching method, a fine wiring pattern can be formed. By using the punching method, the wiring pattern can be formed with simple equipment.
[0015]
In the circuit component built-in module, it is preferable that the mixture further includes at least one additive selected from a dispersant, a colorant, a coupling agent, and a release agent. The inorganic filler in the thermosetting resin can be dispersed with good uniformity by the dispersant. Since the electrically insulating substrate can be colored by the colorant, the heat dissipation of the circuit component built-in module can be improved. Since the bonding agent can increase the adhesive strength between the thermosetting resin and the inorganic filler, the insulating property of the electrically insulating substrate can be improved. Since the mold release agent can improve the mold release property between the mold and the mixture, the productivity can be improved.
[0016]
In the circuit component built-in module, the coefficient of linear expansion of the electrically insulating substrate is 8 × 10. ^-6 / ° C. to 20 × 10 ^-6 It is preferable that the thermal conductivity of the electrically insulating substrate is 1 w / mK to 10 w / mK. This is because a thermal conductivity close to that of a ceramic substrate can be obtained, and a substrate with excellent heat dissipation can be obtained.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
[0027]
(Embodiment 1)
The first embodiment is an example of a circuit component built-in module of the present invention, and FIG. 1 is a perspective sectional view of the circuit component built-in module 100 of the present embodiment.
[0028]
Referring to FIG. 1, a circuit component built-in module 100 of this embodiment includes an electrically insulating substrate 101, wiring patterns 102a and 102b formed on one main surface and another main surface of the electrically insulating substrate 101, wiring A circuit component 103 connected to the pattern 102b and disposed inside the electrically insulating substrate 101, and an inner via 104 for electrically connecting the wiring patterns 102a and 102b are included.
[0029]
The electrically insulating substrate 101 is made of a mixture containing an inorganic filler and a thermosetting resin. For the inorganic filler, for example, Al ₂ O _Three MgO, BN, AlN or SiO ₂ Etc. can be used. The inorganic filler is preferably 70% to 95% by weight based on the mixture. The average particle size of the inorganic filler is preferably 0.1 μm to 100 μm. For the thermosetting resin, for example, epoxy resin, phenol resin or cyanate resin having high heat resistance is preferable. Epoxy resins are particularly preferred because of their particularly high heat resistance. The mixture may further contain a dispersant, a colorant, a coupling agent, or a release agent.
[0030]
The wiring patterns 102a and 102b are made of a material having electrical conductivity, such as a copper foil or a conductive resin composition. When using a copper foil as the wiring pattern, for example, a copper foil having a thickness of about 18 μm to 35 μm manufactured by electrolytic plating can be used. The copper foil desirably has a roughened surface in contact with the electrically insulating substrate 101 in order to improve adhesion with the electrically insulating substrate 101. Further, for the copper foil, a copper foil surface that has been subjected to coupling treatment or a copper foil surface that is plated with tin, zinc, or nickel may be used in order to improve adhesion and oxidation resistance. The wiring patterns 102a and 102b may be a metal plate lead frame formed by an etching method or a punching method.
[0031]
The circuit component 103 includes, for example, an active component 103a and a passive component 103b. As the active component 103a, for example, a semiconductor element such as a transistor, IC, or LSI is used. The semiconductor element may be a semiconductor bare chip. As the passive component 103b, a chip resistor, a chip capacitor, a chip inductor, or the like is used. The circuit component 103 may not include the passive component 103b.
[0032]
For example, flip chip bonding is used to connect the wiring pattern 102b and the active component 103a.
[0033]
The inner via 104 is made of, for example, a thermosetting conductive material. As the thermosetting conductive substance, for example, a conductive resin composition in which metal particles and a thermosetting resin are mixed can be used. As the metal particles, gold, silver, copper, nickel or the like can be used. Gold, silver, copper, or nickel is preferable because of its high conductivity, and copper is particularly preferable because of its high conductivity and low migration. As the thermosetting resin, for example, an epoxy resin, a phenol resin, or a cyanate resin can be used. Epoxy resins are particularly preferred because of their high heat resistance.
[0034]
In the circuit component built-in module 100 shown in the first embodiment, the wiring pattern 102 a and the wiring pattern 102 b are connected by the inner via 104 filled in the through hole of the electrically insulating substrate 101. Therefore, in the circuit component built-in module 100, the circuit components 103 can be mounted with high density.
[0035]
In the circuit component built-in module 100, heat generated in the circuit component is quickly conducted by the inorganic filler contained in the electrically insulating substrate 101. Therefore, a highly reliable circuit component built-in module can be obtained.
[0036]
Further, in the circuit component built-in module 100, by selecting an inorganic filler used for the electrically insulating substrate 101, the linear expansion coefficient, thermal conductivity, dielectric constant, etc. of the electrically insulating substrate 101 can be easily controlled. If the linear expansion coefficient of the electrically insulating substrate 101 is substantially equal to that of the semiconductor element, cracks due to temperature changes can be prevented, and a highly reliable circuit component built-in module can be obtained. When the thermal conductivity of the electrically insulating substrate 101 is improved, a highly reliable circuit component built-in module can be obtained even when circuit components are mounted at a high density. By reducing the dielectric constant of the electrically insulating substrate 101, a high frequency circuit module with low dielectric loss can be obtained.
[0037]
Further, in the circuit component built-in module 100, since the circuit component 103 can be shielded from the outside air by the electrically insulating substrate 101, it is possible to prevent a decrease in reliability due to humidity.
[0038]
Further, the circuit component built-in module 100 of the present invention uses a mixture of an inorganic filler and a thermosetting resin as the material of the electrically insulating substrate 101, so that unlike the ceramic substrate, it is not necessary to fire at a high temperature. Is easy.
[0039]
In the circuit component built-in module 100 shown in FIG. 1, the wiring pattern 102 a is not embedded in the electrically insulating substrate 101. However, the wiring pattern 102 a may be embedded in the electrically insulating substrate 101. (See FIG. 3 (h)).
[0040]
In the circuit component built-in module 100 shown in FIG. 1, the circuit component is not mounted on the wiring pattern 102a. However, the circuit component may be mounted on the wiring pattern 102a. The module may be resin-molded (the same applies to the following embodiments). By mounting circuit components on the wiring pattern 102a, the circuit components can be mounted at a higher density.
[0041]
(Embodiment 2)
In the second embodiment, an embodiment of a method for manufacturing the circuit component built-in module shown in FIG. 1 will be described. The materials and circuit components used in the second embodiment are those described in the first embodiment.
[0042]
2A to 2H are cross-sectional views showing an embodiment of a manufacturing process of a circuit component built-in module.
[0043]
First, as shown to Fig.2 (a), the plate-shaped mixture 200 is formed by processing the mixture containing an inorganic filler and a thermosetting resin. The plate-like mixture 200 can be formed by mixing an inorganic filler and an uncured thermosetting resin into a paste-like kneaded product, and molding the paste-like kneaded product to a certain thickness.
[0044]
The plate-like mixture 200 may be heat-treated at a temperature lower than the curing temperature of the thermosetting resin. By performing the heat treatment, the adhesiveness can be removed while maintaining the flexibility of the mixture 200, so that the subsequent processing becomes easy. In addition, in a mixture in which a thermosetting resin is dissolved with a solvent, a part of the solvent can be removed by heat treatment.
[0045]
Thereafter, as shown in FIG. 2B, by forming the through hole 201 at a desired position of the mixture 200, a plate-like body in which the through hole 201 is formed is formed. The through-hole 201 can be formed by, for example, laser processing, drilling, or die processing. Laser processing is preferable because the through-holes 201 can be formed at a fine pitch and no shavings are generated. In laser processing, if a carbon dioxide laser or excimer laser is used, processing is easy. The through-hole 201 may be formed at the same time when the paste-like kneaded product is formed to form the plate-like mixture 200.
[0046]
Thereafter, as shown in FIG. 2C, the through hole 201 is filled with the conductive resin composition 202 to form a plate-like body in which the through hole 201 is filled with the conductive resin composition 202.
[0047]
In parallel with the steps of FIGS. 2A to 2C, the circuit component 204 is flip-chip bonded to the copper foil 203 as shown in FIG. The circuit component 204 is electrically connected to the copper foil 203 via the conductive adhesive 205. As the conductive adhesive 205, for example, a material obtained by kneading gold, silver, copper, silver-palladium alloy or the like with a thermosetting resin can be used. Also, instead of the conductive adhesive 205, a bump formed by a gold wire bonding method or a bump made of solder is formed in advance on the circuit component side, and the gold or solder is dissolved by heat treatment. use Thus, the circuit component 204 can be mounted. Furthermore, it is also possible to use a solder bump and a conductive adhesive in combination.
[0048]
A sealing resin may be injected between the circuit component 204 mounted on the copper foil 203 and the copper foil 203 (in the following embodiments, between the circuit component and the copper foil or between the circuit component and the wiring pattern). It is the same that the sealing resin may be injected between these. By injecting the sealing resin, it is possible to prevent a gap from being formed between the semiconductor element and the wiring pattern when the semiconductor element is embedded in the plate-like body in a later step. As the sealing resin, an underfill resin used for normal flip chip bonding can be used.
[0049]
In parallel with the steps of FIGS. 2A to 2C, the copper foil 206 is formed.
[0050]
Thereafter, as shown in FIG. 2 (f), the copper foil 203 on which the circuit component 204 is mounted, the plate-like body of FIG. 2 (c), and the copper foil 206 are aligned and overlapped.
[0051]
Thereafter, as shown in FIG. 2 (g), a plate-like body in which the circuit component 204 is embedded is formed by pressurizing the aligned and overlapped layers, and then heated to thereby form the mixture 200 and the conductive layer. The thermosetting resin in the curable resin composition 202 is cured to form a plate-like body in which the circuit component 204 is embedded. The heating is performed at a temperature equal to or higher than the temperature at which the thermosetting resin in the mixture 200 and the conductive resin composition 202 is cured (for example, 150 ° C. to 260 ° C.), and the mixture 200 becomes the electrically insulating substrate 207. The thing becomes the inner via 208. Through this process, the copper foils 203 and 206, the circuit component 204, and the electrically insulating substrate 207 are mechanically firmly bonded. Further, the copper foils 203 and 206 are electrically connected by the inner via 208. In addition, when hardening the thermosetting resin in the mixture 200 and the conductive resin composition 202 by heating, while heating, 10 kg / cm ² ~ 200kg / cm ² The mechanical strength of the circuit component module can be improved by pressurizing at a pressure of (1), which is the same in the following embodiments.
[0052]
Thereafter, as shown in FIG. 2H, the copper foils 203 and 206 are processed to form wiring patterns 209 and 210.
[0053]
In this way, the circuit component built-in module described in the first embodiment is formed. According to the manufacturing method, the circuit component built-in module described in the first embodiment can be easily manufactured.
[0054]
In the second embodiment, the conductive resin composition 202 is used as the conductive material filling the through-hole 201. However, any thermosetting conductive material may be used (the same applies to the following embodiments).
[0055]
(Embodiment 3)
In the third embodiment, another embodiment of the method for manufacturing the circuit component built-in module shown in FIG. 1 will be described. The materials and circuit components used in the third embodiment are those described in the first embodiment.
[0056]
3A to 3H are cross-sectional views illustrating manufacturing steps of the circuit component built-in module according to the third embodiment.
[0057]
First, as shown to Fig.3 (a), the plate-shaped mixture 300 is formed by processing the mixture containing an inorganic filler and a thermosetting resin. Since this step is the same as that in FIG. 2 (a), a duplicate description is omitted.
[0058]
Thereafter, as shown in FIG. 3B, a through hole 301 is formed at a desired position of the mixture 300. Since this step is the same as that in FIG. 2 (b), a duplicate description is omitted.
[0059]
Thereafter, as illustrated in FIG. 3C, the through hole 301 is filled with the conductive resin composition 302 to form a plate-like body in which the through hole 301 is filled with the conductive resin composition 302.
[0060]
In parallel with the steps of FIGS. 3A to 3C, as shown in FIG. 3D, a wiring pattern 303 is formed on the release film 305, and a circuit component 304 is mounted on the wiring pattern 303. The method for mounting the circuit component 304 is the same as the method described with reference to FIG. For the release film 305, for example, a film of polyethylene terephthalate or polyphenylene sulfite can be used. The wiring pattern 303 can be formed, for example, by bonding a copper foil to the release film 305 and then performing a photolithography process and an etching process. The wiring pattern 303 may be a metal plate lead frame formed by etching or punching.
[0061]
In parallel with the steps of FIGS. 3A to 3C, a wiring pattern 306 is formed on the release film 307 as shown in FIG. The wiring pattern 306 can be formed by the same method as the wiring pattern 303.
[0062]
Thereafter, as shown in FIG. 3 (f), the release film 305, the plate-like body of FIG. 2 (c), and the release film 305 are connected so that the wiring patterns 303 and 306 and the conductive material 302 are connected at desired portions. The mold film 307 is aligned and overlapped.
[0063]
Thereafter, as shown in FIG. 3G, the thermosetting resin in the mixture 300 and the conductive resin composition 302 is cured by pressurizing and heating the aligned and overlaid circuit components 304 and A plate-like body in which the wiring patterns 303 and 306 are embedded is formed. The heating is performed at a temperature (for example, 150 ° C. to 260 ° C.) that is equal to or higher than the temperature at which the thermosetting resin in the mixture 300 and the conductive resin composition 302 is cured, and the mixture 300 becomes the electrically insulating substrate 308. The object 302 becomes the inner via 309. The wiring patterns 303 and 306 are electrically connected by the inner via 309.
[0064]
Thereafter, as shown in FIG. 3 (h), the release films 305 and 307 are peeled off from the plate-like body of FIG. 3 (g).
[0065]
In this way, the circuit component built-in module described in the first embodiment is formed. According to the manufacturing method, the circuit component built-in module described in the first embodiment can be easily manufactured.
[0066]
In this method, since the release film 307 in which the wiring pattern 306 is formed in advance is used, it is possible to manufacture a circuit component built-in module in which the wiring pattern 306 is embedded in the electrically insulating substrate 308 and the surface is flat. Since the surface is flat, components can be mounted on the wiring pattern 306 with high density, so that circuit components can be mounted with higher density.
[0067]
(Embodiment 4)
In the fourth embodiment, an embodiment of a circuit component built-in module having a multilayer structure of the present invention will be described. FIG. 4 is a perspective sectional view of the circuit component built-in module 400 of the fourth embodiment.
[0068]
Referring to FIG. 4, a circuit component built-in module 400 of this embodiment includes an electrically insulating substrate 401 composed of laminated electrically insulating substrates 401 a, 401 b and 401 c, and the main surface and the inside of the electrically insulating substrate 401. The formed wiring patterns 402a, 402b, 402c and 402d, the circuit component 403 arranged inside the electrically insulating substrate 401 and connected to the wiring patterns 402a, 402b or 402c, and the wiring patterns 402a, 402b, 402c and 402d And an inner via 404 that is electrically connected.
[0069]
The electrically insulating substrates 401a, 401b and 401c are made of a mixture containing an inorganic filler and a thermosetting resin. For the inorganic filler, for example, Al ₂ O _Three MgO, BN, AlN or SiO ₂ Etc. can be used. The inorganic filler is preferably 70% by weight to 95% by weight with respect to the mixture. The average particle size of the inorganic filler is preferably 0.1 μm to 100 μm. For the thermosetting resin, for example, epoxy resin, phenol resin or cyanate resin having high heat resistance is preferable. Epoxy resins are particularly preferred because of their particularly high heat resistance. The mixture may further contain a dispersant, a colorant, a coupling agent, or a release agent.
[0070]
Since the wiring patterns 402a, 402b, 402c, and 402d are the same as the wiring patterns 102a and 102b described in the first embodiment, redundant description is omitted.
[0071]
The circuit component 403 includes, for example, an active component 403a and a passive component 403b. As the active component 403a, for example, a semiconductor element such as a transistor, IC, or LSI is used. The semiconductor element may be a semiconductor bare chip. As the passive component 403b, a chip resistor, a chip capacitor, a chip inductor, or the like is used. The circuit component 403 may not include the passive component 403b.
[0072]
For example, flip chip bonding is used to connect the wiring patterns 402a, 402b, and 402c to the active component 403a.
[0073]
The inner via 404 is made of, for example, a thermosetting conductive material. As the inner via 404, for example, a conductive resin composition in which metal particles and a thermosetting resin are mixed can be used. As a material of the metal particles, a metal such as gold, silver, copper, or nickel can be used. Gold, silver, copper, or nickel is preferable because of its high conductivity, and copper is particularly preferable because of its high conductivity and low migration. Moreover, as a thermosetting resin, an epoxy resin, a phenol resin, or cyanate resin can be used, for example. Epoxy resins are particularly preferred because of their high heat resistance.
[0074]
In the circuit component built-in module 400 shown in FIG. 4, the wiring pattern 402d is not embedded in the electrically insulating substrate 401c. However, the wiring pattern 402d may be embedded in the electrically insulating substrate 401c. (See FIG. 6 (g)).
[0075]
4 shows the circuit component built-in module 400 having a three-layer structure, it may be a multilayer structure according to the design (the same applies to the following embodiments).
[0076]
(Embodiment 5)
In this fifth embodiment, an embodiment of a method for manufacturing the circuit component built-in module shown in the fourth embodiment will be described. The materials and circuit components used in the fifth embodiment are those described in the fourth embodiment.
[0077]
With reference to FIG. 5, an example of a manufacturing method of the circuit component built-in module shown in the fourth embodiment will be described. 5A to 5H are cross-sectional views showing the manufacturing process of the circuit component built-in module of this embodiment.
[0078]
First, as shown in FIG. 5A, a plate-like mixture 500 is formed by processing a mixture containing an inorganic filler and a thermosetting resin, and a conductive resin composition 501 is filled in the through holes. Thus, a plate-like body in which the through resin is filled with the conductive resin composition 501 is formed. Since this process is the same as the process described with reference to FIGS.
[0079]
On the other hand, the wiring pattern 506 is formed on the release film 503, and the active component 504 and the passive component 505 are mounted on the wiring pattern 506. This process is the same as that described in FIG. 3D, and a duplicate description is omitted.
[0080]
Thereafter, as shown in FIG. 5 (b), the plate-like body of FIG. 5 (a) and the release film 503 are aligned, overlapped and pressed, and then the release film 503 is peeled off, thereby wiring. A plate-like body in which the pattern 506, the active component 504, and the passive component 505 are embedded is formed.
[0081]
In parallel with the steps of FIGS. 5A and 5B, a plurality of plate-like bodies in which the wiring pattern 506 and the circuit components are embedded are formed in the same steps as in FIGS. 5A and 5B (FIG. 5). 5 (c) and (d), see FIGS. 5 (e) and (f)). Note that the wiring pattern 506 and the circuit components are different for each layer depending on the design.
[0082]
Thereafter, as shown in FIG. 5 (g), the plate-like bodies of FIGS. 5 (b), (d) and (f) are aligned and overlapped to form the wiring pattern of the plate-like body of FIG. 5 (f). A copper foil 507 is further stacked on the main surface that is not formed.
[0083]
Then, as shown in FIG.5 (h), the plate-shaped body and copper foil 507 which were piled up in FIG.5 (g) are pressurized and heated, and the plate-shaped body which has a multilayered structure is formed. The heating is performed at a temperature equal to or higher than the temperature at which the thermosetting resin in the mixture 500 and the conductive resin composition 501 is cured (for example, 150 ° C. to 260 ° C.), and the mixture 500 becomes the electrically insulating substrate 508 to form the conductive resin composition. The object 501 becomes an inner via 509. By this process, the circuit components 504 and 505, the copper foil 507, and the electrically insulating substrate 508 are mechanically firmly bonded. Further, the wiring pattern 506 and the copper foil 507 are electrically connected by the inner via 509. Thereafter, the copper foil 507 is processed to form a wiring pattern 510.
[0084]
In this way, a circuit component built-in module having a multilayer structure can be formed. According to the manufacturing method, a circuit component built-in module having a multilayer structure can be easily manufactured.
[0085]
(Embodiment 6)
In the sixth embodiment, another embodiment of the method for manufacturing the circuit component built-in module described in the fourth embodiment will be described. The materials and circuit components used in the sixth embodiment are those described in the fourth embodiment.
[0086]
With reference to FIG. 6, an example of the manufacturing method of the circuit component built-in module in this embodiment will be described. 6A to 6G are cross-sectional views showing the manufacturing process of the circuit component built-in module in this embodiment.
[0087]
First, as shown in FIG. 6 (a), a plate-like mixture 600 is formed by processing a mixture containing an inorganic filler and a thermosetting resin, and a through hole is filled with a conductive material 601 to penetrate the mixture. A plate-like body in which the hole is filled with the conductive resin composition 601 is formed. This process is the same as that described with reference to FIGS. 2A to 2C, and redundant description is omitted. On the other hand, the wiring pattern 606 is formed on the release film 603, and the active component 604 and the passive component 605 are mounted on the wiring pattern 606. This process is the same as that described in FIG. 3D, and a duplicate description is omitted.
[0088]
Thereafter, as shown in FIG. 6 (b), the plate-like mixture 600 of FIG. 6 (a) and the release film 603 are aligned, pressed and pressed, and then the release film 603 is peeled off. Then, a plate-like body in which the wiring pattern 606, the active component 604, and the passive component 605 are embedded is formed.
[0089]
In parallel with the steps of FIGS. 6A and 6B, a plate-like body in which the wiring pattern 606 and the circuit components are embedded is formed in the same step as in FIGS. 6A and 6B (FIG. 6). (See (c) and (d)). Note that the wiring pattern 606 and circuit components differ for each layer depending on the design.
[0090]
In parallel with the steps of FIGS. 6A and 6B, a wiring pattern 607 is formed on the release film 603 as shown in FIG. 6E.
[0091]
Thereafter, as shown in FIG. 6 (f), the plate-like bodies of FIGS. 6 (b) and (d) are aligned and overlapped, and the wiring pattern 606 of the plate-like body of FIG. 6 (d) is not formed. On the main surface, a release film 603 of FIG. 6 (e) is further overlapped so that the wiring pattern 607 is inside.
[0092]
Thereafter, as shown in FIG. 6G, the plate and the release film 603 stacked in FIG. 6F are pressed and heated to form a plate having a multilayer structure. The heating is performed at a temperature (for example, 150 ° C. to 260 ° C.) that is equal to or higher than the temperature at which the thermosetting resin in the mixture 600 and the conductive resin composition 601 is cured, and the mixture 600 becomes the electrically insulating substrate 608, The object 601 becomes an inner via 609. Through this process, the active component 604, the passive component 605, the wiring patterns 606 and 607, and the electrically insulating substrate 608 are mechanically firmly bonded. Further, the wiring patterns 606 and 607 are electrically connected by the inner via 609.
[0093]
Thereafter, the release film 603 is peeled from the plate-like body having a multilayer structure, whereby a circuit component built-in module having a multilayer structure can be formed.
[0094]
Thus, according to the manufacturing method, a circuit component built-in module having a multilayer structure can be easily manufactured.
[0095]
【Example】
Hereinafter, specific examples of the present invention will be described.
[0096]
Example 1
An example of a method for producing an electrically insulating substrate made of a mixture containing an inorganic filler and a thermosetting resin when producing the circuit component built-in module of the present invention will be described.
[0097]
In this example, an electrically insulating substrate was prepared with the composition shown in Table 1. A comparative example is shown as sample number 1.
[0098]
[Table 1]

[0099]
In this example, an epoxy resin (WE-2025, including acid anhydride curing agent) manufactured by Nippon Pernox Co., Ltd. was used as the liquid epoxy resin. As the phenol resin, a phenol resin (Phenolite, VH4150) manufactured by Dainippon Ink Co., Ltd. was used. As the cyanate resin, a cyanate resin (AroCy, M-30) manufactured by Asahi Ciba Co., Ltd. was used. In this example, carbon black or a dispersant was added as an additive.
[0100]
In producing the plate-like body, first, a predetermined amount of a paste-like mixture mixed with the composition shown in Table 1 is dropped onto the release film. The pasty mixture was prepared by mixing an inorganic filler and a liquid thermosetting resin for about 10 minutes with a stirring mixer. The stirring mixer used is one in which an inorganic filler and a liquid thermosetting resin are put into a container of a predetermined capacity and revolved while rotating the container itself. A state is obtained. A 75 μm thick polyethylene terephthalate film was used as the release film, and the film surface was subjected to release treatment with silicon.
[0101]
Next, the release film was further stacked on the paste-like mixture on the release film, and pressed to a thickness of 500 μm with a pressure press to obtain a plate-like mixture.
[0102]
Next, the plate-like mixture sandwiched between the release films was heated together with the release film, and heat-treated under conditions where the stickiness of the plate-like mixture disappeared. The heat treatment is maintained at a temperature of 120 ° C. for 15 minutes. By this heat treatment, the adhesiveness of the plate-like mixture is lost, so that the release film can be easily peeled off. Since the liquid epoxy resin used in this example has a curing temperature of 130 ° C., it is in an uncured state (B stage) under this heat treatment condition.
[0103]
Next, the release film is peeled from the plate-like mixture, and the plate-like mixture is sandwiched between heat-resistant release films (PPS: polyphenylene sulfite, thickness 75 μm), and 50 kg / cm. ² The plate-like mixture was cured by heating at a temperature of 170 ° C. while being pressurized at a pressure of.
[0104]
Next, an electrically insulating substrate was obtained by peeling the heat-resistant release film from the cured plate-like mixture.
[0105]
This electrically insulating substrate was processed into predetermined dimensions, and thermal conductivity, linear expansion coefficient, and the like were measured. The thermal conductivity was obtained by calculation from the temperature rise of the opposite surface by heating the surface of the sample cut into 10 mm square by bringing it into contact with a heater. The linear expansion coefficient was obtained from an average value of the dimensional changes by measuring the dimensional change of the electrically insulating substrate when the temperature was raised from room temperature to 140 ° C. With respect to the withstand voltage, the withstand voltage when an AC voltage was applied in the thickness direction of the electrically insulating substrate was obtained, and the withstand voltage per unit thickness was calculated.
[0106]
As shown in Table 1, the electrically insulating substrate produced by the above method is Al as an inorganic filler. ₂ O _Three Was used, the thermal conductivity was about 10 times or more compared with the conventional glass-epoxy substrate (thermal conductivity 0.2 w / mK to 0.3 w / mK). Al ₂ O _Three The thermal conductivity could be 2.8 w / mK or more by making the amount of 85% by weight or more. Al ₂ O _Three Also has the advantage of low cost.
[0107]
Also, when AlN or MgO is used as the inorganic filler, ₂ O _Three A thermal conductivity equivalent to or higher than that obtained when using was obtained.
[0108]
In addition, amorphous SiO as an inorganic filler ₂ Is used, the linear expansion coefficient is silicon semiconductor (linear expansion coefficient 3 × 10 ^-6 / ° C). Therefore, amorphous SiO as an inorganic filler ₂ Is preferably used as a flip-chip substrate on which a semiconductor is directly mounted.
[0109]
Moreover, SiO as an inorganic filler ₂ When was used, an electrically insulating substrate having a low dielectric constant was obtained. SiO ₂ Has the advantage of low specific gravity. SiO as inorganic filler ₂ The circuit component built-in module using is preferably used as a high-frequency module such as a cellular phone.
[0110]
When BN was used as the inorganic filler, an electrically insulating substrate having a high thermal conductivity and a low coefficient of linear expansion was obtained.
[0111]
As shown in Comparative Example (Sample No. 1) in Table 1, 60% by weight of Al as an inorganic filler ₂ O _Three The dielectric strength voltage of the electrically insulating substrate was 10 kV / mm or more except when using the above. The withstand voltage of the electrically insulating substrate is an index of adhesion between the inorganic filler that is the material of the electrically insulating substrate and the thermosetting resin. That is, when the adhesiveness between the inorganic filler and the thermosetting resin is poor, a minute gap is generated between them and the dielectric strength voltage is lowered. Such a minute gap causes a reduction in the reliability of the circuit component built-in module. In general, if the withstand voltage is 10 kV / mm or more, it can be determined that the adhesion between the inorganic filler and the thermosetting resin is good. Therefore, the amount of the inorganic filler is preferably 70% by weight or more.
[0112]
In addition, since the intensity | strength of an electrically insulating board | substrate will fall when content of a thermosetting resin is low, it is preferable that a thermosetting resin is 4.8 weight% or more.
[0113]
(Example 2)
Example 2 is an example in which a circuit component built-in module was manufactured by the method described in the second embodiment.
[0114]
The composition of the electrically insulating substrate used in this example is Al. ₂ O _Three (AS-40 manufactured by Showa Denko KK, spherical, average particle size 12 μm) is 90% by weight, liquid epoxy resin (manufactured by Nippon Lec Co., Ltd., EF-450) is 9.5% by weight, carbon black (Toyo Carbon) Co., Ltd.) is 0.2 wt%, and the coupling agent (Ajinomoto Co., Titanate, 46B) is 0.3 wt%.
[0115]
A plate-like body (thickness: 500 μm) was produced by treating the above material under the same conditions as in Example 1. The plate-like body was cut into a predetermined size, and a through hole (diameter 0.15 mm) for connecting an inner via hole was formed using a carbon dioxide laser (see FIG. 2B).
[0116]
The through hole was filled with a conductive resin composition by a screen printing method (see FIG. 2C). The conductive resin composition is composed of 85% by weight of spherical copper particles, 3% by weight of bisphenol A type epoxy resin (manufactured by Yuka Shell Epoxy, Epicoat 828), and glycidyl ester epoxy resin (manufactured by Toto Kasei, YD-171). ) 9% by weight and 3% by weight of an amine adduct curing agent (Ajinomoto, MY-24).
[0117]
Next, one side of a 35 μm thick copper foil was roughened, and a semiconductor element was flip-chip bonded to the roughened surface using a conductive adhesive (see FIG. 2D).
[0118]
Next, a copper foil mounted with a semiconductor element, a plate-like body filled with a conductive resin composition, and a separately prepared copper foil (thickness 35 μm with a roughened copper foil on one side) were aligned. It overlapped (refer FIG.2 (f)). At this time, the roughened surface of the copper foil was overlapped so as to be on the plate-like body side.
[0119]
Next, this is heated by a hot press machine at a press temperature of 120 ° C. and a pressure of 10 kg / cm. ² For 5 minutes. Since the thermosetting resin in the plate-like body is softened by heating at a temperature lower than the curing temperature, the semiconductor element was easily embedded in the plate-like body.
[0120]
Next, the heating temperature was raised and heating was performed at 175 ° C. for 60 minutes (see FIG. 2 (g)). By this heating, the epoxy resin in the plate-like body and the epoxy resin in the conductive resin composition were cured, and the semiconductor element, the copper foil, and the plate-like body were mechanically firmly connected. Moreover, the conductive resin composition and the copper foil were electrically (inner via connection) and mechanically connected by this heating.
[0121]
Next, the copper foil on the surface of the plate-like body in which the semiconductor element was embedded was etched by a photolithography process and an etching process to form a wiring pattern (see FIG. 2H). In this way, a circuit component built-in module was created.
[0122]
In order to evaluate the reliability of the circuit component built-in module produced in this example, a solder reflow test and a temperature cycle test were performed. The solder reflow test was performed by repeating a cycle of 10 seconds at a maximum temperature of 260 ° C. using a belt-type reflow tester 10 times. The temperature cycle test was performed by repeating the process of holding at 125 ° C. for 30 minutes and then holding the temperature at −60 ° C. for 30 minutes for 200 cycles.
[0123]
In both the solder reflow test and the temperature cycle test, no crack was generated in the circuit component built-in module of this example, and no abnormality was observed even when an ultrasonic flaw detector was used. From this test, it can be seen that the semiconductor element and the electrically insulating substrate are firmly bonded. Moreover, the resistance value of the inner via connection by the conductive resin composition was hardly changed before and after the test was started.
[0124]
(Example 3)
Example 3 is an example in which a circuit component built-in module is manufactured by the method described in the third embodiment.
[0125]
First, a plate-like body (thickness: 500 μm) in which a through-hole was filled with a conductive resin composition was produced in the same manner as in Example 2 (see FIG. 3C).
[0126]
Next, a copper foil having a thickness of 35 μm was adhered to a release film (manufactured by polyphenylene sulfite, thickness 150 μm) with an adhesive. This copper foil was bonded so that one side was roughened and the glossy side was on the adhesive side.
[0127]
Next, the copper foil on the release film was etched by a photolithography process and an etching process to form a wiring pattern. Further, a semiconductor element was flip-chip bonded onto the wiring pattern using solder bumps (see FIG. 3D).
[0128]
Next, sealing resin was injected into a gap between the semiconductor element mounted on the wiring pattern and the wiring pattern. Specifically, a hot plate heated to 70 ° C. is tilted, and a release film having a wiring pattern on which a semiconductor element is mounted is placed on the hot plate, and then gradually injected with a syringe between the semiconductor element and the wiring pattern. The sealing resin was injected into the. The sealing resin could be injected between the semiconductor element and the wiring pattern in about 10 seconds. The reason for heating with the hot plate is to reduce the viscosity of the sealing resin so that it can be injected in a short time. In addition, the hot plate is inclined in order to facilitate injection. EL18B manufactured by Techno Alpha Co., Ltd. was used as the sealing resin. EL18B is a one-part epoxy resin with SiO ₂ A resin mixed with powder.
[0129]
On the other hand, a release film (made of polyphenylene sulfite, thickness 150 μm) in which a wiring pattern was formed on one surface was produced in parallel with the above process (see FIG. 3E).
[0130]
Next, the release film bonded with the semiconductor element, the plate-like body filled with the conductive resin composition in the through hole, and the release film with the wiring pattern formed on one side were aligned and overlapped. (Refer FIG.3 (f)).
[0131]
Next, this is heated by a hot press machine at a press temperature of 120 ° C. and a pressure of 10 kg / cm. ² For 5 minutes. Since the thermosetting resin in the plate-like body is softened by heating at a temperature lower than the curing temperature, the semiconductor element and the wiring pattern were easily embedded in the plate-like body.
[0132]
Next, the heating temperature was raised and heating was performed at 175 ° C. for 60 minutes (see FIG. 3G). Since the epoxy resin in the plate-like body and the conductive resin composition is cured by this heating, the semiconductor element, the wiring pattern, and the plate-like body are mechanically firmly connected. Moreover, the conductive resin composition and the wiring pattern were electrically (inner via connection) and mechanically connected by this heating. Furthermore, the sealing resin injected between the semiconductor element and the wiring pattern was also cured by this heating.
[0133]
Next, the release film was peeled from the plate-like body (see FIG. 3 (h)). A release film made of polyphenylene sulfite has heat resistance equal to or higher than the heating temperature. Further, the roughened surface of the copper foil is bonded to the plate-like body and the inner via, and the glossy surface of the copper foil is bonded to the release film. Therefore, since the adhesive strength between the plate-like body and the inner via and the copper foil is larger than the adhesive strength between the release film and the copper foil, only the release film can be peeled off. In this way, a circuit component built-in module was created.
[0134]
In order to evaluate the reliability of the circuit component built-in module produced in Example 3, a solder reflow test and a temperature cycle test were performed under the same conditions as in Example 2.
[0135]
In both the solder reflow test and the temperature cycle test, no crack was generated in the circuit component built-in module of Example 3, and no abnormality was observed even when an ultrasonic flaw detector was used. From this test, it can be seen that the semiconductor element and the electrically insulating substrate are firmly bonded. Moreover, the resistance value of the inner via connection by the conductive resin composition was hardly changed before and after the test was started.
[0136]
Example 4
Example 4 is an example in which a circuit component built-in module having a multilayer structure was manufactured by the method described in the fifth embodiment.
[0137]
In Example 4, a semiconductor element and a chip component were used as circuit components.
[0138]
First, a plate-like body in which through holes were filled with a conductive resin composition was formed in the same manner as in Example 2.
[0139]
Next, the plate-like body in which the through hole is filled with the conductive resin composition and the release film (polyphenylene sulfite) having a wiring pattern in which the circuit components are flip-chip bonded are aligned and overlapped. (See FIG. 5 (a)).
[0140]
Next, this is heated by a hot press machine at a press temperature of 120 ° C. and a pressure of 10 kg / cm. ² For 5 minutes. Since the thermosetting resin in the plate-like body is softened by heating at a temperature lower than the curing temperature, the circuit component was easily embedded in the plate-like body. Then, the release film was peeled from the plate-like body to form a plate-like body in which the circuit components were embedded (see FIG. 5B).
[0141]
A plurality of the plate-like bodies were prepared, and the plurality of plate-like bodies and the copper foil were aligned and overlapped (see FIG. 5G).
[0142]
Next, this is heated by a hot press machine at a press temperature of 175 ° C. and a pressure of 50 kg / cm. ² For 60 minutes. By this heat and pressure treatment, a plurality of plate-like bodies in which circuit components are embedded and the copper foil are integrated to form one plate-like body. By this heating and pressurizing treatment, the epoxy resin in the plate-like body and the conductive resin composition was cured, and the circuit component, the wiring pattern, and the plate-like body were mechanically firmly connected. Moreover, the copper foil, the wiring pattern, and the conductive resin composition were electrically (inner via connection) and mechanically connected by this heat and pressure treatment.
[0143]
Next, a wiring pattern was formed by etching the copper foil on the surface of the plate-like body in which the circuit component was embedded by a photolithography process and an etching process (see FIG. 5H). Thus, a circuit component built-in module having a multilayer structure was produced.
[0144]
In order to evaluate the reliability of the circuit component built-in module produced in Example 4, a solder reflow test and a temperature cycle test were performed under the same conditions as in Example 2.
[0145]
In both the solder reflow test and the temperature cycle test, no crack was generated in the circuit component built-in module of Example 4, and no abnormality was observed even when an ultrasonic flaw detector was used. From this test, it can be seen that the semiconductor element and the electrically insulating substrate are firmly bonded. Moreover, the resistance value of the inner via connection by the conductive resin composition was hardly changed before and after the test was started.
[0146]
(Example 5)
Example 5 is an example in which a circuit component built-in module having a multilayer structure was manufactured by the method described in the sixth embodiment.
[0147]
First, a plate-like body in which through holes were filled with a conductive resin composition was formed in the same manner as in Example 2. Next, the plate-like body in which the through hole is filled with the conductive resin composition and the release film (polyphenylene sulfite) having a wiring pattern in which the circuit components are flip-chip bonded are aligned and overlapped. (See FIG. 6 (a)).
[0148]
Next, this is heated by a hot press machine at a press temperature of 120 ° C. and a pressure of 10 kg / cm. ² For 5 minutes. Since the thermosetting resin in the plate-like body is softened by heating at a temperature lower than the curing temperature, the circuit component was easily embedded in the plate-like body. And the plate-shaped body was formed by peeling a release film from a plate-shaped body (refer FIG.6 (b)). Similarly, a plate-like body in which circuit components were embedded was formed (see FIG. 6D).
[0149]
Next, a wiring pattern was formed on one side of a release film (made of polyphenylene sulfite) (see FIG. 6E).
[0150]
Next, the two plate-like bodies in which the circuit components were embedded and the release film on which the wiring pattern was formed were aligned and overlapped (see FIG. 6 (f)).
[0151]
Next, this is heated by a hot press machine at a press temperature of 175 ° C. and a pressure of 50 kg / cm. ² For 60 minutes. By this heat and pressure treatment, a plurality of plate-like bodies in which circuit components were embedded and the release film were integrated to form one plate-like body. By this heat and pressure treatment, the epoxy resin in the plate-like body was cured, and the circuit components, the wiring pattern, and the plate-like body were mechanically firmly connected. Moreover, the epoxy resin in the conductive resin composition was cured by this heat and pressure treatment, and the wiring pattern and the conductive resin composition were electrically (inner via connection) and mechanically connected.
[0152]
Next, the release film was peeled from the integrated plate-like body to produce a circuit component built-in module having a multilayer structure (see FIG. 6G).
[0153]
In order to evaluate the reliability of the circuit component built-in module produced in Example 5, a solder reflow test and a temperature cycle test were performed under the same conditions as in Example 2.
[0154]
In both the solder reflow test and the temperature cycle test, no crack was generated in the circuit component built-in module of Example 5, and no abnormality was observed even when an ultrasonic flaw detector was used. From this test, it can be seen that the semiconductor element and the electrically insulating substrate are firmly bonded. Moreover, the resistance value of the inner via connection by the conductive resin composition was hardly changed before and after the test was started.
[0155]
【The invention's effect】
As described above, in the circuit component built-in module of the present invention, since the electrically insulating substrate made of a mixture of an inorganic filler and a thermosetting resin is used, a circuit component built-in module with high heat dissipation can be obtained.
[0156]
Moreover, in the circuit component built-in module of the present invention, circuit components can be mounted at a higher density by adopting a multilayer structure.
[0157]
Furthermore, in the circuit component built-in module of the present invention, it is possible to control the thermal conductivity, linear expansion coefficient, dielectric constant, etc. of the electrically insulating substrate by selecting an inorganic filler. Accordingly, the circuit component built-in module of the present invention is preferable as a circuit component built-in module incorporating a semiconductor element because the linear expansion coefficient of the electrically insulating substrate can be made substantially the same as that of the semiconductor element. Moreover, since the thermal conductivity of the electrically insulating substrate can be improved, it is preferable as a circuit component built-in module incorporating a semiconductor element or the like that requires heat dissipation. Further, since the dielectric constant of the electrically insulating substrate can be lowered, it is preferable as a circuit component built-in module for a high frequency circuit.
[0158]
In the method for manufacturing a circuit component built-in module of the present invention, the circuit component built-in module can be easily manufactured.
[0159]
Further, in the method for manufacturing a circuit component built-in module according to the present invention, since the wiring pattern can be embedded in the electrically insulating substrate by using the release film on which the wiring pattern is formed, the circuit component built-in module having a smooth surface Is obtained. Therefore, when circuit components are further mounted on the wiring pattern on the surface, the circuit components can be mounted at a high density.
[Brief description of the drawings]
FIG. 1 is a perspective sectional view showing an embodiment of a circuit component built-in module according to the present invention.
FIG. 2 is a process diagram showing an embodiment of a method for producing a circuit component built-in module according to the present invention.
FIG. 3 is a process diagram showing another embodiment of a method for manufacturing a circuit component built-in module according to the present invention.
FIG. 4 is a perspective sectional view showing another embodiment of the circuit component built-in module of the present invention.
FIG. 5 is a process diagram showing another embodiment of a method for producing a circuit component built-in module according to the present invention.
FIG. 6 is a process diagram showing another embodiment of the method for manufacturing a circuit component built-in module according to the present invention.
[Explanation of symbols]
100, 400 Module with built-in circuit components
101, 401, 401a, 401b, 401c Electrically insulating substrate
102a, 102b, 402a, 402b, 402c, 402d Wiring pattern
103, 403 circuit components
103a, 403a Active parts
103b, 403b Passive components
104, 404 Inner via

Claims (11)

An electrically insulating substrate made of a mixture containing 70% to 95% by weight of an inorganic filler and a thermosetting resin;
A first wiring pattern formed on one main surface of the electrically insulating substrate;
A second wiring pattern formed on the other main surface of the electrically insulating substrate;
At least one circuit component embedded in the electrically insulating substrate and electrically connected to the first wiring pattern;
An inner via formed in the electrically insulating substrate so as to electrically connect the first wiring pattern and the second wiring pattern;
It said first buried in the wiring pattern the electrically insulating substrate having a flat surface der is,
The circuit component is embedded in the electrically insulating substrate and the first wiring pattern and the second wiring pattern are electrically connected by the inner via at the same time. Built-in module. Circuit component built-in module according to claim 1, before Symbol circuit components are connected via bumps to said first wiring pattern. The circuit component built-in module according to claim 1, wherein at least two types of circuit components are embedded in the electrically insulating substrate. The circuit component built-in module according to claim 1, wherein the circuit component includes a semiconductor bare chip. The circuit component built-in module according to claim 1, wherein the circuit component includes at least one component selected from a chip-shaped resistor, a chip-shaped capacitor, and a chip-shaped inductor. 5. The circuit component built-in module according to claim 4 , wherein the semiconductor bare chip is flip-chip bonded to the first wiring pattern. The circuit component built-in module according to claim 1, wherein the inner via is made of a conductive resin composition. The circuit component built-in module according to claim 1, wherein the first wiring pattern includes a conductive resin composition. The circuit component built-in module according to claim 1, wherein the wiring pattern is a lead frame of a metal plate formed by an etching method or a punching method. The circuit component built-in module according to claim 1, wherein the mixture further includes at least one additive selected from a dispersant, a colorant, a coupling agent, and a release agent. The linear expansion coefficient of the electrically insulating substrate is 8 × 10 ⁻⁶ / ° C. to 20 × 10 ⁻⁶ / ° C., and the thermal conductivity of the electrically insulating substrate is 1 w / mK to 10 w / mK. circuit component built-in module according to 1.

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