JP4124544B2

JP4124544B2 - LSI device mounting board and manufacturing method thereof

Info

Publication number: JP4124544B2
Application number: JP33613499A
Authority: JP
Inventors: 孝夫赤井; 敦和清水; 敦菊池; 匠井原; 泰史山邉
Original assignee: Fujitsu Ltd
Current assignee: Fujitsu Ltd
Priority date: 1999-11-26
Filing date: 1999-11-26
Publication date: 2008-07-23
Anticipated expiration: 2019-11-26
Also published as: JP2001156221A

Description

【０００１】
【発明の属する技術分野】
本発明は、表面実装型のＬＳＩデバイスを表面実装基板に実装する場合に使用する実装板及びその製造方法に関する。
【０００２】
【従来の技術】
通常、ＬＳＩデバイスは実装基板に実装され、他のＬＳＩデバイス等と組み合わされて所定の機能を持つシステムが構成される。ＬＳＩデバイスの実装形態には、リード挿入型であるＤＩＰ（Dual In-line Package）型や多ピン化に対応したＰＧＡ（Pin Grid Array）型などがあるが、現在では実装効率の観点から表面実装型であるＢＧＡ（Ball Grid Array ）型が主流になっている。
【０００３】
ＢＧＡ型は、ＬＳＩデバイスの格子状の接続端子に半田等の低融点金属のボールを接合させたもので、そのＬＳＩデバイスを表面実装基板の上に載せて加熱すると、低融点金属のボールがＬＳＩデバイスの接続端子と表面実装基板の接続端子を接合するものである。
【０００４】
図１４は、従来のＢＧＡ型のＬＳＩデバイスの実装工程の説明図で、図１４（１）は実装前の断面図であり、図１４（２）は実装後の断面図である。図１４（１）に示すように、ＬＳＩデバイス１７は、キャップ１４内にチップ１５を有し、チップ１５の接続端子２１は、多層基板１６内の配線２２により多層基板１６の下面に設けられた接続端子１８に接続される。
【０００５】
接続端子１８には、半田等の低融点金属のボール６１が接合されており、それぞれのボール６１は、表面実装基板２０の接続端子１９の上に載るように位置合わせされる。この状態で、半田等の低融点金属の融点以上の温度に加熱する。
【０００６】
図１４（２）は、半田等の低融点金属のボール６１が加熱されて溶融し、ＬＳＩデバイス１７の接続端子１８と表面実装基板２０の接続端子１９を接合した状態を示す。このように従来のＢＧＡ型のＬＳＩデバイス１７は、低融点金属の接続部６２が、ＬＳＩデバイス１７と表面実装基板２０を電気的に接続する同時に機械的に接合する。
【０００７】
図１５は、従来のＢＧＡ型のＬＳＩデバイス１７のボール付け工程と実装工程の概略のフローチャートである。ＬＳＩデバイス１７のボール付け工程では、まず、ＬＳＩデバイス１７の接続端子１８にフラックスを塗布し（Ｓ１）、そのフラックスを塗布した位置にボール６１を仮載せする（Ｓ２）。この場合、フラックスを塗布する工程（Ｓ１）及びボール６１を仮載せする工程（Ｓ２）の両者において、接続端子１８と同じ配列のマスク等の治具が必要である。
【０００８】
次に、ボール６１を接続端子１８に仮載せした状態で、半田等の低融点金属の融点以上の温度に加熱し、ボール６１を接続端子１８に接合する（Ｓ３）。その後、ボール６１と接続端子１８を洗浄して（Ｓ４）ボール付け工程を終了する。
【０００９】
ＬＳＩデバイス１７の実装工程は、まず、表面実装基板２０の接続端子１９に半田等の低融点金属を塗布し（Ｓ５）、ＬＳＩデバイス１７を表面実装基板２０の上に搭載し（Ｓ６）、ボール６１と接続端子１９の位置を合わせる。そして、半田等の低融点金属の融点以上の温度に加熱し、ＬＳＩデバイス１７の接続端子１８を表面実装基板２０の接続端子１９に接合する（Ｓ７）。
【００１０】
【発明が解決しようとする課題】
ＢＧＡ型のＬＳＩデバイス１７は、実装効率が高く多ピン化への対応も可能であるが、ＬＳＩデバイス１７の接続端子１８に半田等の低融点金属のボール６１を接合するのに多数の工程を要し、接続端子１８にフラックスを塗布しボール６１を仮載せするのに専用マスク等の治具が必要である。
【００１１】
また、半田等の低融点金属の接続部６２は、接続端子１８、１９を電気的に接続する同時に、ＬＳＩデバイス１７と表面実装基板２０を機械的に接合する役目を果たすが、半田等の低融点金属は機械的強度が低く、実装後の信頼性が低いという課題がある。
【００１２】
また、従来のＢＧＡ型のＬＳＩデバイス１７は、半田等の低融点金属の接続部６２の間隔が極めて小さいので、半田ブリッジや微小なゴミにより接続部６２が短絡する恐れがある。更に、接続部６２において信号配線の特性インピーダンスにミスマッチが生じ、ＬＳＩデバイス１７と表面実装基板２０の間の接合部６２でインピーダンス整合がとれず、高速のＬＳＩデバイス１７を表面実装基板２０に搭載した場合に誤動作が生じる恐れがある。
【００１３】
そこで、本発明の目的は、表面実装型のＬＳＩデバイスを表面実装基板に実装する場合に、実装工程を削減することができるＬＳＩデバイスの実装板及びその製造方法を提供することにある。
【００１４】
また、本発明の他の目的は、表面実装型のＬＳＩデバイスを表面実装基板に実装する場合に、実装信頼性を向上することができるＬＳＩデバイスの実装板及びその製造方法を提供することにある。
【００１５】
更に、本発明の他の目的は、表面実装型のＬＳＩデバイスを表面実装基板に実装する場合に、インピーダンス整合が可能なＬＳＩデバイスの実装板及びその製造方法を提供することにある。
【００１６】
【課題を解決するための手段】
上記の目的を達成するために、本発明の一つの側面は、ＬＳＩデバイスの接続端子群に対応して配置された格子状の低融点金属及び樹脂を有する実装板を、ＬＳＩデバイスと表面実装基板の間に配置して熱工程を加え、ＬＳＩデバイスを表面実装基板に実装することを特徴とする。
【００１７】
本発明によれば、従来必要であったボール仮付け工程を省略することができると共に、ボール仮付けのための専用マスク類等の治具が不要になり、実装工程を簡略化することができる。また、低融点金属相互間が樹脂により絶縁されるので、低融点金属が短絡される恐れがない。更に、ＬＳＩデバイスと表面実装基板の接合が樹脂により補強されるので、ＬＳＩデバイスと表面実装基板の接合の機械的強度を向上させることができる。
【００１８】
上記の目的を達成するために、本発明の別の側面は、格子状の第１の接続端子群を有する表面実装型のＬＳＩデバイスを、前記第１の接続端子群に接続される格子状の第２の接続端子群を有する表面実装基板に実装する実装板において、前記第１と第２の接続端子群に対応して配置された格子状の低融点金属と、前記格子状の低融点金属と一体に形成され、前記低融点金属のそれぞれを絶縁する樹脂とを有することを特徴とする。
【００１９】
本発明によれば、ＬＳＩデバイスを表面実装基板に実装する場合において、単一の熱工程により、低融点金属による接合と樹脂による接合を同時に行うことができ、実装工程を簡略化することができる。また、低融点金属による接合が樹脂による接合で補強されるので、実装の機械的強度を向上させることができる。更に、低融点金属の間に樹脂が存在するので、低融点金属が短絡する恐れがなく、信頼性の高い接続を行うことができる。
【００２０】
また、上記の発明において、その好ましい態様は、前記格子状の低融点金属の間に、接地用の導電部材が設けられることを特徴とする。
【００２１】
本発明によれば、格子状の低融点金属の中間に接地用の導電部材が設けられるので、ＬＳＩデバイスと表面実装基板をストリップライン構造又は同軸構造に近いシールド構造で接続することができる。従って、ＬＳＩデバイスと表面実装基板の間の接続端子においてもインピーダンスを整合させることができると共に、低融点金属相互間の干渉がなくなり、外部からのノイズの侵入を防止することができる。
【００２２】
また、上記の発明において、その好ましい態様は、前記格子状の低融点金属の間に、スリット又は前記樹脂と熱膨張係数が異なる部材が設けられることを特徴とする。
【００２３】
本発明によれば、格子状の低融点金属の中間にスリット又は熱膨張係数が異なる部材が設けられるので、実装するＬＳＩデバイスの熱膨張による変形を吸収することができる。従って、ＬＳＩデバイス及び表面実装基板に無理な力が加わることを防止し、実装の機械的強度を向上させることができる。
【００２４】
更に、上記の発明において、その好ましい態様は、前記ＬＳＩデバイスが接合される面に、前記ＬＳＩデバイスを嵌め込み可能な窪みが設けられることを特徴とする。
【００２５】
本発明によれば、ＬＳＩデバイスが接合される面にＬＳＩデバイスを嵌め込み可能な窪みが設けられるので、ＬＳＩデバイスと実装板の位置合わせが容易になり、実装工程を簡略化することができる。更に、実装板の周辺部の樹脂がＬＳＩデバイスの側面を表面実装基板に接合するので、ＬＳＩデバイスの実装強度を向上させることができる。
【００２６】
また、上記の目的を達成するために、本発明の別の側面は、格子状の第１の接続端子群を有する表面実装型のＬＳＩデバイスを、前記第１の接続端子群に接続される格子状の第２の接続端子群を有する表面実装基板に実装する実装板の製造方法において、棒状の低融点金属と棒状の樹脂とを、前記棒状の低融点金属及び棒状の前記樹脂の長手方向に垂直な方向に、かつ、前記低融点金属が前記第１と第２の接続端子群に対応するように交互に重ね合わせて直方体を形成し、前記直方体を、前記樹脂の硬化温度より低い温度で加熱して一体化し、一体化した前記直方体を、前記棒状の低融点金属及び前記棒状の樹脂の長手方向に垂直な方向に所定の厚さに切断することを特徴とする。
【００２７】
本発明によれば、棒状の低融点金属と棒状の樹脂を重ね合わせて実装板を形成するので、多種多様なＬＳＩデバイスの接続端子の配列に対して、低融点金属の棒の配列を容易に対応させることができる。
【００２８】
【発明の実施の形態】
以下、図面を参照して本発明の実施の形態例を説明する。しかしながら、かかる実施の形態例が、本発明の技術的範囲を限定するものではない。
【００２９】
図１は、本発明の実施の形態の実装板の構成図である。本実施の形態の実装板１３は、図１（１）に示すように、例えば０．５〜０．６ｍｍ程度の厚さｔを有し、実装するＬＳＩデバイスと表面実装基板の接続端子に対応して格子状に配置された半田等の低融点金属１２と、低融点金属１２と一体に形成され、低融点金属１２のそれぞれを絶縁する硬化前のエポキシ等の樹脂１１とを有する。
【００３０】
図１（２）は、本実施の形態の実装板１３をＬＳＩデバイス１７と表面実装基板２０の間に配置した接合前の断面図である。即ち、実装板１３の低融点金属１２は、ＬＳＩデバイス１７の接続端子１８と表面実装基板２０の接続端子１９に対応する位置に位置決めされ、低融点金属１２の融点以上の温度に加熱されて接続端子１８と接続端子１９を接合する。なお、樹脂１１は、低融点金属１２の融点より低い硬化温度を有する。
【００３１】
図１（３）は、実装板１３が低融点金属１２の融点以上の温度に加熱され、ＬＳＩデバイス１７が表面実装基板２０に実装された場合の部分拡大図である。図１（３）に示すように、低融点金属１２は、溶融後に硬化し、多層基板１６の接続端子１８と表面実装基板２０の接続端子１９を接合する。一方、樹脂１１は、低融点金属１２の溶融後に硬化し、多層基板１６と表面実装基板２０の対向面の接続端子１８、１９以外の部分を接合する。
【００３２】
このように本実施の形態の実装板１３を使用すれば、ボール付け工程が不要になり実装工程が簡略化されると共に、リフロー等の熱工程により、低融点金属１２による接合と樹脂１１による接合を同時に行うことができる。
【００３３】
従って、表面実装型のＬＳＩデバイス１７を表面実装基板２０に実装する場合に、低融点金属１２による接合が樹脂１１による接合で補強されるので、実装の機械的強度を向上させることができる。また、低融点金属１２の間には絶縁物である樹脂１１が存在するので、低融点金属１２が短絡する恐れがなく、信頼性の高い接続を行うことができる。
【００３４】
図２は、本実施の形態の加熱工程の温度変化の例である。図２では、低融点金属１２として融点が１８３℃の半田を用い、樹脂１１の硬化温度が約１５０℃の場合について説明する。
【００３５】
図１（２）のように、実装板１３をＬＳＩデバイス１７と表面実装基板２０の間に挿入した状態で、時間ｔ1 から時間ｔ２まで温度を約１５０℃に保持する。この期間は、例えば約５〜６分であり、樹脂１１が溶融しながら徐々に硬化し、フラックスが活性化して半田の接合が容易になる。
【００３６】
次に、樹脂１１の硬化が完了する前に、時間ｔ２から時間ｔ３までの例えば約１０〜２０秒間、１８３℃以上の温度に加熱する。この期間に半田が溶融し、表面実装基板２０の接続端子１９と多層基板１６の接続端子１８との間で、実装板１３が微妙に動き、正しい位置に自動的に位置合わせされる。時間ｔ３以降は温度を降下させて半田を硬化させ、実装工程を終了する。
【００３７】
このように本実施の形態の実装板１３は、溶融した半田と硬化前の樹脂１１により正しい位置に自動的に位置合わせされるので、多層基板１６と表面実装基板２０の接続端子１８、１９の多少のずれを吸収し、機械的強度の高い接合を行うことができる。
【００３８】
図３は、本発明の実施の形態の実装板１３の製造工程の説明図である。本実施の形態の実装板１３を製造するには、まず、図３（１）に示す所定の長さの半田等の低融点金属の棒２５と、図３（２）に示す硬化前のエポキシ等の樹脂の棒２６を交互に重ね合わせ、図３（３）に示すように、半田等の低融点金属の棒２５が実装するＬＳＩデバイス１７の接続端子１８の配列と同じになるような直方体２７を形成する。
【００３９】
次に、この直方体２７を樹脂硬化温度よりも低い温度で加熱し、低融点金属の棒２５と樹脂の棒２６を接合させて一体化する。そして、一体化した直方体２７を、図１（１）のように所定の厚さｔに切り出して実装板１３を形成する。
【００４０】
このように本実施の形態の実装板１３は、低融点金属の棒２５と樹脂の棒２６を重ね合わせて形成するので、多種多様なＬＳＩデバイス１７の接続端子１８の配列に対して、低融点金属の棒２５の配列を容易に対応させることができる。
【００４１】
図４は、本発明の他の実施の形態の実装板１３の製造工程の説明図である。本実施の形態の実装板１３は、図３の場合と同様に、半田等の低融点金属の棒２５と硬化前のエポキシ等の樹脂の棒２６を交互に重ね合わせ、図４（３）に示すような直方体２７を形成する。
【００４２】
ただし本実施の形態では、図４（２）に示すように、樹脂の棒２６が低融点金属の棒２５の周囲を囲むように構成されるので、以下に示すように、低融点金属の棒２５を任意の形状にすることができる。
【００４３】
図５は、本発明の他の実施の形態の実装板１３の説明図である。本実施の形態の実装板１３は、図４に示したように、樹脂の棒２６が低融点金属の棒２５の周囲を囲むように構成されるので、低融点金属１２の断面形状を、ＬＳＩデバイス１７及び表面実装基板２０の接続端子１８、１９の形状に合わせて任意の形状にすることができる。
【００４４】
即ち、図５（１）は低融点金属１２の断面が円の場合であり、図５（２）は菱形の場合であり、図５（３）は楕円の場合である。本実施の形態の実装板１３によれば、低融点金属１２の断面形状をＬＳＩデバイス１７及び表面実装基板２０の接続端子１８、１９の形状に合わせることができ、実装の機械的強度を向上させることができる。
【００４５】
図６は、本発明の他の実施の形態の実装板１３の断面図である。本実施の形態の実装板１３は、図４の場合とほぼ同様の構成であるが、低融点金属１２を囲む一組の樹脂１１と他の一組の樹脂１１の間に、例えば、金属板、金属箔又は金属網等の導電部材３１を一方向に挿入する。そして、それぞれの導電部材３１は、接続線３２により表面実装基板２０の接地端子に接続される。
【００４６】
本実施の形態の実装板１３によれば、ＬＳＩデバイス１７及び表面実装基板２０の間をストリップライン構造で接続することができ、実装板１３の部分においても信号線のインピーダンスを整合させることができる。
【００４７】
図７は、本発明の他の実施の形態の実装板１３の断面図である。本実施の形態の実装板１３は、図６の場合とほぼ同様の構成であるが、低融点金属１２を囲む一組の樹脂１１と他の一組の樹脂１１の間に導電部材３１を縦・横両方向に挿入する。そして、それぞれの導電部材３１は、接続線３２により表面実装基板２０の接地端子に接続される。
【００４８】
本実施の形態の実装板１３によれば、ＬＳＩデバイス１７及び表面実装基板２０を同軸構造に近いシールド構造で接続することができ、低融点金属１２相互間の干渉がなくなり、また、外部からのノイズの侵入を防止することができる。
【００４９】
図８は、本発明の他の実施の形態の実装板１３の製造工程の説明図である。本実施の形態の実装板１３は、図４の場合と同様に、半田等の低融点金属の棒２５と硬化前のエポキシ等の樹脂の棒２６を交互に重ね合わせ、図８（３）に示すような直方体２７を形成する。ただし、本実施の形態の樹脂の棒２６は、図８（２）に示すような切り欠き３５が設けられる。
【００５０】
この直方体２７を加熱して一体化し、所定の厚さｔに切り出して実装板１３が形成されるが、本実施の形態の実装板１３は、樹脂１１の中に、図８（３）に示すスリット３６が形成される。従って、スリット３６がＬＳＩデバイス１７の熱膨張による変形を吸収し、ＬＳＩデバイス１７及び表面実装基板２０に無理な力が加わることを防止し、実装の機械的強度を向上させることができる。
【００５１】
図９は、本発明の他の実施の形態の実装板１３の製造工程の説明図である。本実施の形態の実装板１３は、図８に示した構造とほぼ同様であるが、図９（１）に示す半田等の低融点金属の棒２５と、図９（２ａ）に示す硬化前のエポキシ等の樹脂の棒２６と、図９（２ｂ）に示す熱膨張係数が異なる部材の棒４１を交互に重ね合わせ、図９（３）に示すような直方体２７を形成する。この場合に、樹脂の棒２６は、熱膨張係数が異なる部材の棒４１が嵌め込まれる切り欠き３５が設けられる。
【００５２】
この直方体２７を加熱して一体化し、所定の厚さｔに切り出して実装板１３が形成されるが、本実施の形態の実装板１３は、樹脂１１の中に、図９（３）に示す熱膨張係数が異なる部材の棒４１が組み込まれる。
【００５３】
従って、熱膨張係数が異なる部材４１により、実装するＬＳＩデバイス１７の熱膨張による変形を補償できるので、表面実装基板２０及びＬＳＩデバイス１７に無理な力が加わることを防止し、実装の信頼性を向上させることができる。
【００５４】
図１０は、本発明の他の実施の形態の実装板１３の構成図である。本実施の形態の実装板１３は、図１０（１）に示すように、半田等の低融点金属１２と硬化前のエポキシ等の樹脂１１が一体に形成され、ＬＳＩデバイス１７が実装される面に、ＬＳＩデバイス１７が嵌め込まれる窪み４５が設けられる。また、窪み４５には、ＬＳＩデバイス１７の嵌め込み方向を規定するインデックス４６が設けられる。
【００５５】
図１０（２）は、実装板１３をＬＳＩデバイス１７と表面実装基板２０の間に配置した加熱前の断面図である。即ち、本実施の形態では、ＬＳＩデバイス１７は、実装板１３の窪み４５に嵌め込まれ、表面実装基板２０と位置合わせが行われる。このため、本実施の形態の実装板１３では、ＬＳＩデバイス１７の接続端子１８と実装板１３の位置合わせが省略でき、実装工程を簡略化することができる。
【００５６】
図１０（３）は、実装板１３が低融点金属１２の融点以上の温度に加熱され、ＬＳＩデバイス１７が表面実装基板２０に実装された場合の部分拡大図である。図１０（３）に示すように、低融点金属１２は、溶融後に硬化して多層基板１６に設けられた接続端子１８と、表面実装基板２０の接続端子１９を接合する。一方、樹脂１１は、溶融後に硬化して、多層基板１６と表面実装基板２０の対向面の接続端子１８、１９以外の部分を接合する。更に、本実施の形態の実装板１３は、周辺部の樹脂１１がＬＳＩデバイス１７の側面を表面実装基板２０に接合するので、ＬＳＩデバイス１７の実装強度を向上させることができる。
【００５７】
図１１は、本発明の実施の形態の実装板１３の製造方法の説明図である。本実施の形態の実装板１３の製造方法は、型５１の中にＬＳＩデバイス１７の接続端子１８に対応するように低融点金属の棒２５を立てて配列し、型５１の中に溶融させた熱可塑性の樹脂を流し込む。その後、樹脂を冷却し、樹脂と低融点金属の棒２５が一体化した直方体を形成する。一体化した直方体を、低融点金属の棒２５の長手方向に垂直な方向に所定の厚さｔに切断して実装板１３を形成することは上述の実施の形態と同様である。
【００５８】
本実施の形態の実装板１３の製造方法によれば、型５１の中に溶融させた熱可塑性の樹脂を流し込むので、樹脂と低融点金属の棒２５が一体化した直方体を容易に形成することができる。
【００５９】
図１２は、本発明の他の実施の形態の実装板１３の製造方法の説明図である。本実施の形態の実装板１３の製造方法は、型５１の中にＬＳＩデバイス１７の接続端子１８に対応するように低融点金属の棒２５を横に並べて配列し、型５１の中に溶融させた熱可塑性の樹脂を流し込む。その後に実装板１３を形成する工程は、上述の実施の形態と同様である。
【００６０】
本実施の形態の実装板１３の製造方法においても、型５１の中に溶融させた熱可塑性の樹脂を流し込むので、樹脂と低融点金属の棒２５が一体化した直方体を容易に形成することができる。
【００６１】
図１３は、本発明の他の実施の形態の実装板１３の製造工程の説明図である。本実施の形態の実装板１３は、金属板等の導電部材５５に、エッチング又は機械加工により大口径の孔５６と小口径の孔５７を設け、その孔５６、５７の中に、小口径の孔５７とほぼ同じ口径の低融点金属の棒２５を挿入する。
【００６２】
次に、大口径の孔５６と低融点金属の棒２５の間に溶融させた熱可塑性の樹脂を流し込み、樹脂と低融点金属の棒２５及び導電部材５５が一体になった直方体２７を形成する。
【００６３】
次に、一体化した直方体２７を使用する厚さに切断し、実装板１３を形成することは上述の実施の形態と同様である。本実施の形態の実装板１３によれば、低融点金属１２が樹脂により絶縁されるので、低融点金属１２が短絡する恐れがない。また、ＬＳＩデバイス１７と表面実装基板２０の接合が樹脂により補強されるので、ＬＳＩデバイス１７の実装信頼性を向上させることができる。
【００６４】
また、小口径の孔５７に挿入した低融点金属１２を接地すれば、導電部材５５は接地電位になる。従って、本実施の形態の実装板１３は、同軸構造に近いシールド構造をとることができ、高速のＬＳＩデバイスを実装した場合の誤動作を減少させることができる。
【００６５】
本発明の保護範囲は、上記の実施の形態に限定されず、特許請求の範囲に記載された発明とその均等物に及ぶものである。
【００６６】
【発明の効果】
以上、本発明によれば、従来必要であったボール仮付け工程を省略することができると共に、ボール仮付けのための専用マスク類等の治具が不要になり、実装工程を簡略化することができる。また、低融点金属相互間が樹脂により絶縁されるので、低融点金属が短絡される恐れがない。更に、ＬＳＩデバイスと表面実装基板の接合が樹脂により補強されるので、ＬＳＩデバイスと表面実装基板の接合の機械的強度を向上させることができる。
【００６７】
また、本発明によれば、格子状の低融点金属の中間に接地用の導電部材が設けられるので、ＬＳＩデバイスと表面実装基板をストリップライン構造又は同軸構造に近いシールド構造で接続することができる。従って、ＬＳＩデバイスと表面実装基板の間の実装板においてもインピーダンスを整合させることができると共に、低融点金属相互間の干渉がなくなり、外部からのノイズの侵入を防止することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態の実装板の構成図である。
【図２】加熱工程の温度変化の例である。
【図３】本発明の実施の形態の実装板の製造工程の説明図である。
【図４】本発明の他の実施の形態の実装板の製造工程の説明図である。
【図５】本発明の実施の形態の実装板の導体部の形状例である。
【図６】一方向に導電部材を挿入した実装板の断面図である。
【図７】縦・横両方向に導電部材を挿入した実装板の断面図である。
【図８】本発明の他の実施の形態の実装板の製造工程の説明図である。
【図９】本発明の他の実施の形態の実装板の製造工程の説明図である。
【図１０】本発明の他の実施の形態の実装板の構成図である。
【図１１】低融点金属を立てて配列し、溶融させた樹脂を流し込む製造方法の説明図である。
【図１２】低融点金属を横に配列し、溶融させた樹脂を流し込む製造方法の説明図である。
【図１３】本発明の他の実施の形態の実装板の製造工程の説明図である。
【図１４】従来のＬＳＩデバイスの実装工程の説明図である。
【図１５】従来のボール付け工程と実装工程のフローチャートである。
【符号の説明】
１１樹脂
１２低融点金属
１３実装板
１７ＬＳＩデバイス
１８、１９接続端子
２０表面実装基板
２５低融点金属の棒
２６樹脂の棒
２７直方体
３１、５５導電部材
３６スリット
４１熱膨張係数の異なる部材の棒
４５窪み
５１型
５６、５７孔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mounting board used when a surface-mount type LSI device is mounted on a surface-mount substrate, and a method for manufacturing the same.
[0002]
[Prior art]
Usually, an LSI device is mounted on a mounting board, and a system having a predetermined function is configured in combination with another LSI device or the like. LSI device mounting forms include lead insertion type DIP (Dual In-line Package) type and PGA (Pin Grid Array) type that supports multiple pins, but now surface mounting from the viewpoint of mounting efficiency BGA (Ball Grid Array) type, which is the type, has become the mainstream.
[0003]
In the BGA type, a low melting point metal ball such as solder is bonded to a lattice connection terminal of an LSI device. When the LSI device is placed on a surface mounting substrate and heated, the low melting point metal ball is transformed into an LSI. The connection terminal of the device and the connection terminal of the surface mount substrate are joined.
[0004]
FIG. 14 is an explanatory diagram of a mounting process of a conventional BGA type LSI device, FIG. 14 (1) is a sectional view before mounting, and FIG. 14 (2) is a sectional view after mounting. As shown in FIG. 14 (1), the LSI device 17 has a chip 15 in the cap 14, and the connection terminal 21 of the chip 15 is provided on the lower surface of the multilayer substrate 16 by the wiring 22 in the multilayer substrate 16. Connected to the connection terminal 18.
[0005]
Balls 61 of low melting point metal such as solder are joined to the connection terminals 18, and the respective balls 61 are aligned so as to be placed on the connection terminals 19 of the surface mounting substrate 20. In this state, it is heated to a temperature higher than the melting point of a low melting point metal such as solder.
[0006]
FIG. 14B shows a state in which a low melting point metal ball 61 such as solder is heated and melted to join the connection terminal 18 of the LSI device 17 and the connection terminal 19 of the surface mounting substrate 20. In this way, in the conventional BGA type LSI device 17, the low melting point metal connecting portion 62 electrically connects the LSI device 17 and the surface mounting substrate 20 at the same time and mechanically joins.
[0007]
FIG. 15 is a schematic flowchart of a ball attaching process and a mounting process of the conventional BGA type LSI device 17. In the ball attaching step of the LSI device 17, first, flux is applied to the connection terminal 18 of the LSI device 17 (S1), and the ball 61 is temporarily placed at the position where the flux is applied (S2). In this case, a jig such as a mask having the same arrangement as the connection terminals 18 is required in both the step of applying flux (S1) and the step of temporarily placing the balls 61 (S2).
[0008]
Next, in a state where the ball 61 is temporarily placed on the connection terminal 18, the ball 61 is heated to a temperature equal to or higher than the melting point of a low melting point metal such as solder to join the ball 61 to the connection terminal 18 (S 3). Thereafter, the balls 61 and the connection terminals 18 are washed (S4), and the ball attaching step is completed.
[0009]
In the mounting process of the LSI device 17, first, a low melting point metal such as solder is applied to the connection terminals 19 of the surface mounting substrate 20 (S5), and the LSI device 17 is mounted on the surface mounting substrate 20 (S6). 61 and the connection terminal 19 are aligned. And it heats to the temperature more than melting | fusing point of low melting metals, such as solder, and the connection terminal 18 of LSI device 17 is joined to the connection terminal 19 of the surface mounting board | substrate 20 (S7).
[0010]
[Problems to be solved by the invention]
The BGA type LSI device 17 has high mounting efficiency and can cope with the increase in the number of pins. However, many steps are required to join the low melting point metal balls 61 such as solder to the connection terminals 18 of the LSI device 17. In other words, a jig such as a dedicated mask is required to apply the flux to the connection terminals 18 and temporarily place the balls 61 thereon.
[0011]
The low melting point metal connection part 62 such as solder serves to mechanically join the LSI device 17 and the surface mounting substrate 20 at the same time as the connection terminals 18 and 19 are electrically connected. There is a problem that the melting point metal has low mechanical strength and low reliability after mounting.
[0012]
Further, in the conventional BGA type LSI device 17, since the interval between the connection portions 62 of the low melting point metal such as solder is very small, the connection portions 62 may be short-circuited by a solder bridge or a minute dust. Furthermore, a mismatch occurs in the characteristic impedance of the signal wiring at the connection portion 62, and impedance matching cannot be achieved at the joint portion 62 between the LSI device 17 and the surface mounting substrate 20, and the high speed LSI device 17 is mounted on the surface mounting substrate 20. In some cases, malfunction may occur.
[0013]
SUMMARY OF THE INVENTION An object of the present invention is to provide an LSI device mounting board and a method for manufacturing the same that can reduce the mounting process when a surface-mount LSI device is mounted on a surface-mount substrate.
[0014]
Another object of the present invention is to provide an LSI device mounting plate and a method for manufacturing the same that can improve mounting reliability when a surface-mount LSI device is mounted on a surface-mount substrate. .
[0015]
Furthermore, another object of the present invention is to provide an LSI device mounting plate capable of impedance matching when a surface-mount LSI device is mounted on a surface-mount substrate, and a method for manufacturing the same.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, according to one aspect of the present invention, there is provided a mounting board having a lattice-shaped low melting point metal and a resin arranged corresponding to a connection terminal group of an LSI device. It is characterized in that the LSI device is mounted on a surface mounting substrate by applying a thermal process by placing it between the two.
[0017]
According to the present invention, it is possible to omit a ball tacking process that has been conventionally required, and a jig such as a dedicated mask for ball tacking becomes unnecessary, and the mounting process can be simplified. . Moreover, since the low melting point metals are insulated from each other by the resin, there is no possibility that the low melting point metal is short-circuited. Furthermore, since the bonding between the LSI device and the surface mounting substrate is reinforced by the resin, the mechanical strength of the bonding between the LSI device and the surface mounting substrate can be improved.
[0018]
In order to achieve the above object, another aspect of the present invention provides a surface-mount type LSI device having a grid-like first connection terminal group and a grid-like shape connected to the first connection terminal group. A mounting board to be mounted on a surface mounting substrate having a second connection terminal group, a lattice-shaped low melting point metal disposed corresponding to the first and second connection terminal groups, and the lattice-shaped low melting point metal And a resin that insulates each of the low-melting-point metals.
[0019]
According to the present invention, when an LSI device is mounted on a surface mounting substrate, bonding with a low melting point metal and bonding with a resin can be performed simultaneously by a single thermal process, and the mounting process can be simplified. . In addition, since the bonding with the low melting point metal is reinforced by the bonding with the resin, the mechanical strength of the mounting can be improved. Furthermore, since the resin exists between the low melting point metals, there is no fear that the low melting point metal is short-circuited, and a highly reliable connection can be made.
[0020]
In the above invention, a preferred embodiment is characterized in that a conductive member for grounding is provided between the lattice-shaped low melting point metals.
[0021]
According to the present invention, since the grounding conductive member is provided in the middle of the lattice-shaped low melting point metal, the LSI device and the surface mount substrate can be connected by a shield structure close to a stripline structure or a coaxial structure. Therefore, impedance can be matched also at the connection terminal between the LSI device and the surface mounting substrate, and interference between the low melting point metals can be eliminated, so that intrusion of noise from the outside can be prevented.
[0022]
In the above invention, a preferable aspect thereof is characterized in that a slit or a member having a thermal expansion coefficient different from that of the resin is provided between the lattice-like low melting point metals.
[0023]
According to the present invention, since a slit or a member having a different coefficient of thermal expansion is provided in the middle of a lattice-like low melting point metal, deformation due to thermal expansion of the mounted LSI device can be absorbed. Therefore, it is possible to prevent an excessive force from being applied to the LSI device and the surface mounting substrate, and to improve the mechanical strength of the mounting.
[0024]
Furthermore, in the above-described invention, a preferable aspect thereof is characterized in that a recess into which the LSI device can be fitted is provided on a surface to which the LSI device is bonded.
[0025]
According to the present invention, since the recess into which the LSI device can be fitted is provided on the surface to which the LSI device is bonded, the alignment of the LSI device and the mounting board is facilitated, and the mounting process can be simplified. Further, since the resin in the peripheral portion of the mounting board joins the side surface of the LSI device to the surface mounting substrate, the mounting strength of the LSI device can be improved.
[0026]
In order to achieve the above object, another aspect of the present invention provides a grid in which a surface-mount LSI device having a grid-like first connection terminal group is connected to the first connection terminal group. In a method for manufacturing a mounting board to be mounted on a surface-mounting substrate having a second group of connection terminals, a rod-shaped low melting point metal and a rod-shaped resin are placed in the longitudinal direction of the rod-shaped low melting point metal and the rod-shaped resin. A rectangular parallelepiped is formed by vertically superimposing the low melting point metal so as to correspond to the first and second connection terminal groups in a vertical direction, and the rectangular parallelepiped is formed at a temperature lower than the curing temperature of the resin. Heating and integrating, the integrated rectangular parallelepiped is cut into a predetermined thickness in a direction perpendicular to the longitudinal direction of the rod-shaped low melting point metal and the rod-shaped resin.
[0027]
According to the present invention, since the mounting plate is formed by superimposing the rod-shaped low melting point metal and the rod-shaped resin, the arrangement of the low melting point metal rods can be easily performed with respect to the arrangement of the connection terminals of various LSI devices. Can be matched.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. However, such an embodiment does not limit the technical scope of the present invention.
[0029]
FIG. 1 is a configuration diagram of a mounting board according to an embodiment of the present invention. As shown in FIG. 1 (1), the mounting board 13 of the present embodiment has a thickness t of, for example, about 0.5 to 0.6 mm, and corresponds to the connecting terminals of the LSI device to be mounted and the surface mounting board. Then, a low melting point metal 12 such as solder arranged in a lattice shape, and a resin 11 such as an epoxy before curing, which is formed integrally with the low melting point metal 12 and insulates each of the low melting point metal 12.
[0030]
FIG. 1B is a cross-sectional view before joining, in which the mounting board 13 of the present embodiment is disposed between the LSI device 17 and the surface mounting board 20. That is, the low melting point metal 12 of the mounting board 13 is positioned at a position corresponding to the connection terminal 18 of the LSI device 17 and the connection terminal 19 of the surface mounting substrate 20 and is connected by being heated to a temperature higher than the melting point of the low melting point metal 12. The terminal 18 and the connection terminal 19 are joined. The resin 11 has a curing temperature lower than the melting point of the low melting point metal 12.
[0031]
FIG. 1 (3) is a partially enlarged view when the mounting board 13 is heated to a temperature equal to or higher than the melting point of the low melting point metal 12 and the LSI device 17 is mounted on the surface mounting substrate 20. As shown in FIG. 1 (3), the low melting point metal 12 is cured after melting, and joins the connection terminals 18 of the multilayer substrate 16 and the connection terminals 19 of the surface mount substrate 20. On the other hand, the resin 11 is cured after the low melting point metal 12 is melted, and joins the portions other than the connection terminals 18 and 19 on the opposing surfaces of the multilayer substrate 16 and the surface mount substrate 20.
[0032]
If the mounting board 13 according to the present embodiment is used in this way, a ball attaching step is not required, and the mounting step is simplified. In addition, the bonding by the low melting point metal 12 and the bonding by the resin 11 are performed by a heat process such as reflow. Can be performed simultaneously.
[0033]
Therefore, when the surface-mounted LSI device 17 is mounted on the surface-mounting substrate 20, the bonding by the low melting point metal 12 is reinforced by the bonding by the resin 11, so that the mechanical strength of the mounting can be improved. Moreover, since the resin 11 which is an insulator exists between the low melting point metals 12, there is no fear that the low melting point metal 12 is short-circuited, and a highly reliable connection can be made.
[0034]
FIG. 2 is an example of a temperature change in the heating process of the present embodiment. In FIG. 2, a case where solder having a melting point of 183 ° C. is used as the low melting point metal 12 and the curing temperature of the resin 11 is about 150 ° C. will be described.
[0035]
As shown in FIG. 1B, the temperature is maintained at about 150 ° C. from time t1 to time t2 with the mounting board 13 being inserted between the LSI device 17 and the surface mounting board 20. This period is, for example, about 5 to 6 minutes. The resin 11 is gradually cured while being melted, the flux is activated, and the solder is easily joined.
[0036]
Next, before the curing of the resin 11 is completed, the resin 11 is heated to a temperature of 183 ° C. or more for about 10 to 20 seconds from time t2 to time t3. During this period, the solder melts, and the mounting board 13 moves slightly between the connection terminals 19 of the surface mounting board 20 and the connection terminals 18 of the multilayer board 16 and is automatically aligned at the correct position. After time t3, the temperature is lowered to cure the solder, and the mounting process is completed.
[0037]
As described above, the mounting board 13 of the present embodiment is automatically aligned at the correct position by the molten solder and the resin 11 before curing, so that the connection terminals 18 and 19 of the multilayer board 16 and the surface mounting board 20 are connected. It can absorb a slight deviation and can perform bonding with high mechanical strength.
[0038]
FIG. 3 is an explanatory diagram of the manufacturing process of the mounting board 13 according to the embodiment of the present invention. In order to manufacture the mounting board 13 of the present embodiment, first, a low melting point metal rod 25 such as solder having a predetermined length shown in FIG. 3 (1) and an uncured epoxy shown in FIG. 3 (2). As shown in FIG. 3 (3), resin rods 26 such as solder are alternately stacked, and a rectangular parallelepiped that has the same arrangement as the connection terminals 18 of the LSI device 17 on which the low melting point metal rods 25 such as solder are mounted. 27 is formed.
[0039]
Next, the rectangular parallelepiped 27 is heated at a temperature lower than the resin curing temperature, and the low melting point metal rod 25 and the resin rod 26 are joined and integrated. Then, the integrated rectangular parallelepiped 27 is cut out to a predetermined thickness t as shown in FIG.
[0040]
As described above, the mounting board 13 of the present embodiment is formed by superimposing the low melting point metal rod 25 and the resin rod 26 so that the low melting point is different from the arrangement of the connection terminals 18 of various LSI devices 17. The arrangement of the metal bars 25 can be easily matched.
[0041]
FIG. 4 is an explanatory diagram of the manufacturing process of the mounting board 13 according to another embodiment of the present invention. As in the case of FIG. 3, the mounting board 13 of the present embodiment alternately overlaps a low melting point metal rod 25 such as solder and a resin rod 26 such as epoxy before curing, as shown in FIG. A rectangular parallelepiped 27 as shown is formed.
[0042]
However, in the present embodiment, as shown in FIG. 4B, the resin rod 26 is configured to surround the periphery of the low-melting-point metal rod 25. Therefore, as shown below, the low-melting-point metal rod 25 can be any shape.
[0043]
FIG. 5 is an explanatory diagram of the mounting board 13 according to another embodiment of the present invention. As shown in FIG. 4, the mounting board 13 of the present embodiment is configured such that the resin rod 26 surrounds the periphery of the low melting point metal rod 25. Arbitrary shapes can be formed in accordance with the shapes of the connection terminals 18 and 19 of the device 17 and the surface mounting substrate 20.
[0044]
That is, FIG. 5 (1) is a case where the cross section of the low melting point metal 12 is a circle, FIG. 5 (2) is a case of a rhombus, and FIG. 5 (3) is a case of an ellipse. According to the mounting board 13 of the present embodiment, the cross-sectional shape of the low melting point metal 12 can be matched with the shape of the connection terminals 18 and 19 of the LSI device 17 and the surface mounting substrate 20, thereby improving the mechanical strength of the mounting. be able to.
[0045]
FIG. 6 is a cross-sectional view of the mounting board 13 according to another embodiment of the present invention. The mounting plate 13 of the present embodiment has substantially the same configuration as that in FIG. 4, but a metal plate, for example, between a pair of resins 11 surrounding the low melting point metal 12 and another set of resins 11. A conductive member 31 such as a metal foil or a metal net is inserted in one direction. Each conductive member 31 is connected to the ground terminal of the surface mount substrate 20 by a connection line 32.
[0046]
According to the mounting board 13 of the present embodiment, the LSI device 17 and the surface mounting board 20 can be connected in a stripline structure, and the impedance of the signal line can be matched also in the mounting board 13 portion. .
[0047]
FIG. 7 is a cross-sectional view of a mounting board 13 according to another embodiment of the present invention. The mounting board 13 of the present embodiment has substantially the same configuration as that of FIG. 6, but the conductive member 31 is vertically disposed between a pair of resins 11 surrounding the low melting point metal 12 and another set of resins 11.・ Insert in both lateral directions. Each conductive member 31 is connected to the ground terminal of the surface mount substrate 20 by a connection line 32.
[0048]
According to the mounting board 13 of the present embodiment, the LSI device 17 and the surface mounting substrate 20 can be connected with a shield structure close to a coaxial structure, and there is no interference between the low melting point metals 12, and from the outside Intrusion of noise can be prevented.
[0049]
FIG. 8 is an explanatory diagram of the manufacturing process of the mounting board 13 according to another embodiment of the present invention. As in the case of FIG. 4, the mounting board 13 of the present embodiment alternately overlaps a low melting point metal rod 25 such as solder and a resin rod 26 such as epoxy before curing, as shown in FIG. A rectangular parallelepiped 27 as shown is formed. However, the resin rod 26 of the present embodiment is provided with a notch 35 as shown in FIG.
[0050]
The rectangular parallelepiped 27 is integrated by heating and cut out to a predetermined thickness t to form the mounting board 13. The mounting board 13 of the present embodiment is shown in FIG. A slit 36 is formed. Therefore, the slit 36 absorbs deformation due to thermal expansion of the LSI device 17, prevents an excessive force from being applied to the LSI device 17 and the surface mounting substrate 20, and improves the mechanical strength of mounting.
[0051]
FIG. 9 is an explanatory diagram of the manufacturing process of the mounting board 13 according to another embodiment of the present invention. The mounting board 13 of the present embodiment is substantially the same as the structure shown in FIG. 8, but a low melting point metal rod 25 such as solder shown in FIG. 9 (1) and the pre-curing shown in FIG. 9 (2a). The rods 26 of resin such as epoxy and the rods 41 of members having different coefficients of thermal expansion shown in FIG. 9 (2b) are alternately overlapped to form a rectangular parallelepiped 27 as shown in FIG. 9 (3). In this case, the resin rod 26 is provided with a notch 35 into which a rod 41 of a member having a different thermal expansion coefficient is fitted.
[0052]
The rectangular parallelepiped 27 is integrated by heating and cut out to a predetermined thickness t to form the mounting board 13. The mounting board 13 of the present embodiment is shown in FIG. A bar 41 of a member having a different thermal expansion coefficient is incorporated.
[0053]
Therefore, since the deformation due to the thermal expansion of the LSI device 17 to be mounted can be compensated by the member 41 having a different thermal expansion coefficient, it is possible to prevent an excessive force from being applied to the surface mounting substrate 20 and the LSI device 17 and to improve the mounting reliability. Can be improved.
[0054]
FIG. 10 is a configuration diagram of the mounting board 13 according to another embodiment of the present invention. As shown in FIG. 10A, the mounting board 13 of the present embodiment is a surface on which an LSI device 17 is mounted by integrally forming a low melting point metal 12 such as solder and a resin 11 such as epoxy before curing. In addition, a recess 45 into which the LSI device 17 is fitted is provided. In addition, the recess 45 is provided with an index 46 that defines the fitting direction of the LSI device 17.
[0055]
FIG. 10B is a cross-sectional view before heating in which the mounting board 13 is disposed between the LSI device 17 and the surface mounting substrate 20. That is, in the present embodiment, the LSI device 17 is fitted into the recess 45 of the mounting board 13 and aligned with the surface mounting board 20. For this reason, in the mounting board 13 of the present embodiment, the alignment of the connection terminal 18 of the LSI device 17 and the mounting board 13 can be omitted, and the mounting process can be simplified.
[0056]
FIG. 10 (3) is a partially enlarged view when the mounting board 13 is heated to a temperature equal to or higher than the melting point of the low melting point metal 12 and the LSI device 17 is mounted on the surface mounting substrate 20. As shown in FIG. 10 (3), the low melting point metal 12 hardens after melting and joins the connection terminals 18 provided on the multilayer substrate 16 and the connection terminals 19 of the surface mount substrate 20. On the other hand, the resin 11 is cured after being melted, and joins the portions other than the connection terminals 18 and 19 on the opposing surfaces of the multilayer substrate 16 and the surface mounting substrate 20. Further, the mounting plate 13 of the present embodiment can improve the mounting strength of the LSI device 17 because the peripheral resin 11 bonds the side surface of the LSI device 17 to the surface mounting substrate 20.
[0057]
FIG. 11 is an explanatory diagram of a method for manufacturing the mounting board 13 according to the embodiment of the present invention. In the manufacturing method of the mounting board 13 according to the present embodiment, the low melting point metal rods 25 are arranged upright in the mold 51 so as to correspond to the connection terminals 18 of the LSI device 17 and melted in the mold 51. Pour thermoplastic resin. Thereafter, the resin is cooled to form a rectangular solid in which the resin and the low melting point metal rod 25 are integrated. The mounting plate 13 is formed by cutting the integrated rectangular parallelepiped into a predetermined thickness t in a direction perpendicular to the longitudinal direction of the low melting point metal rod 25 as in the above-described embodiment.
[0058]
According to the method of manufacturing the mounting board 13 of the present embodiment, since the molten thermoplastic resin is poured into the mold 51, a rectangular parallelepiped in which the resin and the low melting point metal rod 25 are integrated is easily formed. Can do.
[0059]
FIG. 12 is an explanatory diagram of a method for manufacturing the mounting board 13 according to another embodiment of the present invention. In the manufacturing method of the mounting board 13 of the present embodiment, the low melting point metal rods 25 are arranged side by side in the mold 51 so as to correspond to the connection terminals 18 of the LSI device 17, and are melted in the mold 51. Pour a thermoplastic resin. The process of forming the mounting board 13 after that is the same as that of the above-mentioned embodiment.
[0060]
Also in the manufacturing method of the mounting board 13 of the present embodiment, since the molten thermoplastic resin is poured into the mold 51, it is possible to easily form a rectangular solid in which the resin and the low melting point metal rod 25 are integrated. it can.
[0061]
FIG. 13 is an explanatory diagram of the manufacturing process of the mounting board 13 according to another embodiment of the present invention. In the mounting plate 13 of the present embodiment, a large-diameter hole 56 and a small-diameter hole 57 are provided in a conductive member 55 such as a metal plate by etching or machining, and the small-diameter hole 56 is formed in the holes 56 and 57. A low melting point metal rod 25 having the same diameter as the hole 57 is inserted.
[0062]
Next, a molten thermoplastic resin is poured between the large-diameter hole 56 and the low melting point metal rod 25 to form a rectangular parallelepiped 27 in which the resin, the low melting point metal rod 25 and the conductive member 55 are integrated. .
[0063]
Next, the integrated rectangular parallelepiped 27 is cut into a thickness to be used, and the mounting board 13 is formed as in the above-described embodiment. According to the mounting board 13 of the present embodiment, since the low melting point metal 12 is insulated by the resin, there is no possibility that the low melting point metal 12 is short-circuited. Further, since the bonding between the LSI device 17 and the surface mounting substrate 20 is reinforced by the resin, the mounting reliability of the LSI device 17 can be improved.
[0064]
Further, when the low melting point metal 12 inserted into the small-diameter hole 57 is grounded, the conductive member 55 becomes the ground potential. Therefore, the mounting board 13 of this embodiment can have a shield structure close to a coaxial structure, and can reduce malfunctions when a high-speed LSI device is mounted.
[0065]
The protection scope of the present invention is not limited to the above-described embodiment, but covers the invention described in the claims and equivalents thereof.
[0066]
【The invention's effect】
As described above, according to the present invention, it is possible to omit the ball tacking process that has been necessary in the past and to eliminate the need for jigs such as dedicated masks for ball tacking, thereby simplifying the mounting process. Can do. Moreover, since the low melting point metals are insulated from each other by the resin, there is no possibility that the low melting point metal is short-circuited. Furthermore, since the bonding between the LSI device and the surface mounting substrate is reinforced by the resin, the mechanical strength of the bonding between the LSI device and the surface mounting substrate can be improved.
[0067]
Further, according to the present invention, since the grounding conductive member is provided in the middle of the lattice-shaped low melting point metal, the LSI device and the surface mount substrate can be connected with a shield structure close to a stripline structure or a coaxial structure. . Therefore, impedance can be matched also in the mounting board between the LSI device and the surface mounting board, and interference between the low melting point metals is eliminated, so that intrusion of noise from the outside can be prevented.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a mounting board according to an embodiment of the present invention.
FIG. 2 is an example of a temperature change in a heating process.
FIG. 3 is an explanatory diagram of a manufacturing process of the mounting board according to the embodiment of the present invention.
FIG. 4 is an explanatory diagram of a manufacturing process of a mounting board according to another embodiment of the present invention.
FIG. 5 is a shape example of a conductor portion of the mounting board according to the embodiment of the present invention.
FIG. 6 is a cross-sectional view of a mounting board with a conductive member inserted in one direction.
FIG. 7 is a cross-sectional view of a mounting board in which conductive members are inserted in both vertical and horizontal directions.
FIG. 8 is an explanatory diagram of a manufacturing process of a mounting board according to another embodiment of the present invention.
FIG. 9 is an explanatory diagram of a manufacturing process of a mounting board according to another embodiment of the present invention.
FIG. 10 is a configuration diagram of a mounting board according to another embodiment of the present invention.
FIG. 11 is an explanatory diagram of a manufacturing method in which low melting point metals are arranged in a standing manner and molten resin is poured.
FIG. 12 is an explanatory diagram of a manufacturing method in which low melting point metals are arranged horizontally and molten resin is poured.
FIG. 13 is an explanatory diagram of a manufacturing process of a mounting board according to another embodiment of the present invention.
FIG. 14 is an explanatory diagram of a conventional LSI device mounting process.
FIG. 15 is a flowchart of a conventional ball attaching process and a mounting process.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Resin 12 Low melting point metal 13 Mounting board 17 LSI device 18, 19 Connection terminal 20 Surface mounting board 25 Low melting point metal rod 26 Resin rod 27 Rectangular body 31, 55 Conductive member 36 Slit 41 Rod 45 of member having different thermal expansion coefficients Recess 51 type 56, 57 hole

Claims

In a manufacturing method of a mounting board for mounting a surface mount type LSI device having a first connection terminal group on a surface mount substrate having a second connection terminal group connected to the first connection terminal group,
A rod-shaped low melting point metal and a rod-shaped resin are arranged in a direction perpendicular to the longitudinal direction of the rod-shaped low melting point metal and the rod-shaped resin, and the low melting point metal is added to the first and second connection terminal groups. A rectangular parallelepiped is formed by alternately overlapping to correspond,
The rectangular parallelepiped is integrated by heating at a temperature lower than the curing temperature of the resin,
A method for manufacturing a mounting board, comprising cutting the integrated rectangular parallelepiped to a predetermined thickness in a direction perpendicular to a longitudinal direction of the rod-shaped low melting point metal and the rod-shaped resin.

In a manufacturing method of a mounting board for mounting a surface mount type LSI device having a first connection terminal group on a surface mount substrate having a second connection terminal group connected to the first connection terminal group,
A plurality of holes corresponding to the first and second connection terminal groups are opened in the conductive member,
A rod-shaped low melting point metal is disposed in each hole,
Pour molten thermoplastic resin into the gap between the inner surface of each hole where the rod-shaped low melting point metal is disposed and the rod-shaped low melting point metal,
The resin is cooled, the resin, the low melting point metal and the conductive member are integrated to form a rectangular parallelepiped,
A method for manufacturing a mounting board, comprising cutting the integrated rectangular parallelepiped to a predetermined thickness in a direction perpendicular to a longitudinal direction of the rod-shaped low melting point metal.