JP4108773B2

JP4108773B2 - IC chip sealing method

Info

Publication number: JP4108773B2
Application number: JP03482096A
Authority: JP
Inventors: 浩平圓地; 朗壁下; 真司金山
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1996-02-22
Filing date: 1996-02-22
Publication date: 2008-06-25
Anticipated expiration: 2016-02-22
Also published as: JPH09232347A

Description

【０００１】
【発明の属する技術分野】
本発明は、ＩＣ実装におけるフリップチップ実装工程およびＭＣＭ実装工程に関するものである。
【０００２】
【従来の技術】
近年、ＩＣ実装におけるフリップチップ実装工程およびＭＣＭ（マルチチップモジュール）実装工程での、封止工程は大きく分けて、２種類の方法がある。
【０００３】
第１の方法はＩＣチップ装着後、封止を行う方法として一般的に行われているもので、図５（ａ）、（ｂ）に示す方法である。この方法は、ＩＣチップ２がフリップチップ（出力端子が突起上にバンプ付けされたＩＣチップを直接基板の端子に接続する方法）されたＩＣ基板３をステージ４上に水平に置き、ディスペンスノズル１をその出口断面が基板と平行になるように配置し、例えば移動軌跡Ｌのように、ノズル１をＩＣチップ２の面上を移動させ封止剤６を塗布してＩＣチップ２の全面を覆うもので、側面部からの封止剤６の入り込みにより封止が行なわれる。ディスペンスノズル１としては、手動方式、エアー圧力またはピストンポンプまたは電動回転スクリューの圧力で容器内部の封止剤６を容器の出力部に送り、針状のノズルの先端から封止剤６を吐出するものが使用される。
【０００４】
第２の方法は、図６に示すように、基板３上に封止剤を塗らずにフリップチップされたＩＣチップ２の側面外側からディスペンスノズル１を、ＩＣチップ２及び基板３に触れず、かつ、ＩＣチップ２から側方への所定距離９及びＩＣ基板３から上方への所定距離１０（ＩＣチップの隙間７よりも大きく、ＩＣチップの厚み＋ＩＣチップの隙間の合計距離８よりも小さい距離）を保って移動しながら、吐出した封止剤６をＩＣチップ２の外側面全周に塗布することにより、封止剤６の濡れ性だけで、隙間７に封止剤６を入り込ませるものである。
【０００５】
【発明が解決しようとする課題】
しかし、上記の従来の第１の方法では、封止剤６がＩＣチップ２の上面をも覆っていることから、ＩＣチップ２の放熱が要求された場合でも、直接放熱板に取り付けることができず、またＩＣチップ２の厚みが大となって、厚み方向に制約を受けた場合、使用出来なくなる。
【０００６】
また、従来の第２の方法では、粘度が高い封止剤６の場合、その濡れ性だけによってＩＣチップ２のバンプ接続部の隙間７に封止剤６がスムースに入り込むことができず、また気泡を巻き込む状態となり、封止工程の後の工程に高温（９０〜１００°Ｃ）プロセスがある場合、バンプ接続部が気泡の膨張による圧力に圧迫されて接続不良になるケースが多い。
【０００７】
本発明は、上記のような従来の問題点を解消し、ＩＣチップ面上への封止剤のはみ出しや接続部隙間への気泡巻き込み等の不都合を伴うことなく、的確に封止効果を達成できるＩＣチップの封止方法を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記の目的を達成するため、本願の第１発明のＩＣチップ封止方法は、ＩＣチップを基板上に装着した後、ＩＣチップと基板との間の隙間を封止剤で封止する方法において、基板を水平面に対して５°以上３０°以下の角度をもって傾斜させた状態において、ディスペンスノズルを、その吐出口の基板からの高さ位置がＩＣチップの上下面の中間になるように保って、ＩＣチップの上辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、ディスペンスノズルの上記移動を１回又は繰り返して、ＩＣチップと基板との間に粘着液状態の封止剤を充填することを特徴とする。
【０００９】
上記の目的を達成するため、本願の第２発明のＩＣチップ封止方法は、ＩＣチップが搭載された基板を水平面に対して５°以上３０°以下の角度をもって傾斜させた状態において、前記ＩＣチップと基板との間の隙間に、ディスペンスノズルを、その吐出口の基板からの高さ位置がＩＣチップの上下面の中間になるように保って、ＩＣチップの上辺に沿って相対的に移動させながら、前記上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、次いで前記基板を略水平面内で所定角度回転させ、かつ前記基板を水平面に対して所定角度をもって傾斜させ、粘着液状態の封止剤を上記と同様にして再吐出供給することを特徴とする。
【００１０】
上記の目的を達成するため、本願の第３発明のＩＣチップ封止方法は、上記第２発明において、ＩＣチップと基板との間の隙間に、前記ＩＣチップの上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、次いで前記基板を略水平面内で１８０°回転させ、かつ、前記基板を水平面内に対して所定角度をもって傾斜させ、粘着液状態の封止剤を再吐出供給することを特徴とする。
【００１１】
上記の目的を達成するため、本願の第４発明のＩＣチップ封止方法は、ＩＣチップを基板上に装着した後、ＩＣチップと基板との間の隙間を封止剤で封止する方法において、基板を水平面に対して５°以上３０°以下の角度をもって傾斜させた状態において、基板の傾斜方向の基準線に対し、それぞれ所定角度傾斜するように上方左辺と上方右辺とが位置するようにＩＣチップを配置した状態で、ディスペンスノズルを、その吐出口の基板からの高さ位置がＩＣチップの上下面の中間になるように保って、ＩＣチップの上方左辺及び上方右辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上方左辺及び上方右辺に沿った隙間口から粘着液状態の封止剤を吐出供給することを特徴とする。
【００１２】
上記の目的を達成するため、本願の第５発明のＩＣチップ封止方法は、上記第４発明において、基板を水平面に対して所定角度をもって傾斜させ、基板の傾斜方向の基準線に対し、ほぼ４５°づつ傾斜するように上方左辺と上方右辺とが位置するようにＩＣチップを配置した状態で、ディスペンスノズルをＩＣチップの上方左辺及び上方右辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上方左辺及び上方右辺に沿った隙間口から粘着液状態の封止剤を吐出供給することを特徴とする。
【００１３】
上記目的を達成するため、本願の第６発明のＩＣチップの封止方法は、上記第５発明において、ＩＣチップと基板との間に、前記上方左辺および前記上方右辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、次いで基板を略水平面内で１８０°回転させて、ＩＣチップの元の下方右辺及び下方左辺を前記上方左辺及び上方右辺に位置させた状態で上記と同様ディスペンスノズルから粘着液状態の封止剤を吐出供給することを特徴とする。なお上記各発明においては、基板を水平面に対する基板の傾斜角は５°〜３０°の範囲の角度とすること、基板を高温状態のステージ上に配置することが望ましい。
【００１４】
本願の第１発明によれば、基板を水平面に対して所定角度をもって傾斜させ、ディスペンスノズルをＩＣチップの上辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、ディスペンスノズルの上記移動を繰り返して、ＩＣチップと基板との間に粘着液状態の封止剤を充填しているので、即ち、ＩＣ基板を水平面に対して傾斜して設置し、ＩＣチップの上辺に沿ってノズルを移動しながら封止剤を吐出して線引き塗布を行うので、封止剤がその濡れ性だけでなく、さらに自重によりＩＣ隙間にスムースかつ一方向に流れ込んでいき、気泡の巻き込みを極力押さえることができる。
【００１５】
さらに、封止剤がＩＣ表面を覆うことがないので、ＩＣの放熱が要求された場合にはＩＣ表面を直接放熱板に取り付けることができ、また封止されたＩＣがチップ厚み分のみの最小寸法であるので、ＩＣの厚み方向に制約を受けた場合にも何ら支障を来たさない。
【００１６】
また、本願の第２、３発明によれば、ＩＣチップを基板上に装着した後、ＩＣチップと基板との間の隙間を封止剤で封止する方法において、基板を水平面に対して所定角度をもって傾斜させ、ディスペンスノズルをＩＣチップの上辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、次いで基板を略水平面内で所定角度、例えば１８０°回転させ、ＩＣチップの元の下辺を前記上辺位置に位置させた状態で上記と同様に粘着液状態の封止剤を吐出供給することにより、即ち、ＩＣチップを回転させて対向２辺それぞれを上辺に位置させた状態で、上辺に沿って封止剤を線引き塗布し封止剤を行うので、前記第１発明に比較し気泡の巻き込みという点では若干劣るが、これに比較して生産性を高めることができると共に封止剤の分布がより均等化され、好ましい封止結果を得ることができる。
【００１７】
また、本願の第２発明において、基板を水平面に対して所定角度をもって傾斜させ、基板の傾斜方向に対しほぼ直角方向に上辺と下辺とが位置するようにＩＣチップを配置した状態で、ディスペンスノズルをＩＣチップの上辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上辺に沿った隙間口から粘着液状態の封止剤を吐出供給し、次いで順次基板を回転させ、ＩＣチップの元の下辺、左辺、右辺のそれぞれを前記上辺位置に位置させた状態で上記と同様にディスペンスノズルから粘着液状態の封止剤を吐出供給することにより、即ち、ＩＣチップを９０度単位で回転させ、各辺を順次上辺に位置させた状態で、それぞれに封止剤の線引き塗布を行うようにすることができ、この場合前記第１発明に比較し、気泡の巻き込みという点では劣るが、これに比較し格段に短時間で封止を行うことができる。
【００１８】
本願の第４、第５発明によれば、ＩＣチップを基板上に装着した後、ＩＣチップと基板との間の隙間を封止剤で封止する方法において、基板を水平面に対して所定角度をもって傾斜させ、基板の傾斜方向の基準線に対し、それぞれ所定角度、例えばほぼ４５°傾斜するように上方左辺と上方右辺とが位置するようにＩＣチップを配置した状態で、ディスペンスノズルをＩＣチップの上方左辺及び上方右辺に沿って相対的に移動させながら、ＩＣチップと基板との間の隙間に、前記上方左辺及び上方右辺に沿った隙間口から粘着液状態の封止剤を吐出供給することにより、即ち、傾斜面において、四辺形ＩＣチップの隣接２辺を傾斜面の上側に位置させ、この２辺からほぼ同時に線引き塗布を行うことにより、塗布回数少なく短時間に効率良く、しかも気泡の巻き込みなく封止を行うことができる。
【００１９】
本願の第６発明によれば、基板を１８０度回転させ新しく上側に位置した、基準線に対して４５°傾斜の隣接２辺から封止を行うことにより、前記第５発明に比較し、気泡の巻き込みという点では若干劣るが、これに比較し一層短時間で封止を行うことができる。
【００２０】
【発明の実施の形態】
（実施形態１）
図１は、本発明の第１の実施形態におけるＩＣチツプの封止方法の斜視構成図（ａ）、断面図（ｂ）及び基板とノズルの配置状態図（ｃ）である。
【００２１】
先ず、封止を行うＩＣ基板３を載置するためのステージ４を、水平面に対して所定の角度α傾斜した状態に設置する。この傾斜角αは、ＩＣチップ２の大きさや封止剤６の粘度等によっても異なるが、５°〜３０°程度の所定の角度が好ましく、１５°前後が最適である。なおこの角度は、封止作業中固定した一定の角度に設定してもよいが、場合によっては封止剤吐出の際の傾斜角とその後の吐出剤流動期間における傾斜角とを、上記所定角度範囲内で異なる値に設定することもできる。
【００２２】
また基板３上の封止剤６の粘度を低下させるため、ステージ４の温度を或る一定の温度に設定して、基板３を適当な温度に加熱しておくための温度制御手段を設置することが好適である。この温度は、封止剤６の種類により異なり、たとえば６０°Ｃの場合もあるが、時には常温の場合もあり得る。
【００２３】
なお、ステージ４上方には、特に図示されていないが、ＩＣ基板を装着するための装着機構を備え、一方ステージ４の中央部下面側にはその法線方向に向いた回転軸が設けられ、ステージ４をその傾斜面内で任意の角度に回転できるように構成されている。回転軸は、駆動モータ、電源及び制御手段により、任意の角度に駆動しかつ設定できるように構成されている。なお、ステージ４の傾斜角、従って回転軸の傾斜角を調節可能とし、手動調節または所定のプログラムにより変化できるように構成しておいてもよい。
【００２４】
このステージ４の上に、四角形状のＩＣチップ２の辺１１（例えば図のＡＢ）が長方形基板３の辺１２（例えばＣＤ）に対し平行に配置された状態でＩＣチップ２がフリップチップされたＩＣ基板３を、ステージ４の辺１３（例えばＥＦ）と基板３の側辺１２との関係が平行となるように保持する。
【００２５】
図１の（ｃ）に示すように、ディスペンスノズル１を、その出口面が基板３の面に平行となる向きに配置する。この状態では、水平面に対するステージ４の傾斜角αが１５°の場合は、水平面とノズルの軸方向との角度は７５°となる。
【００２６】
次に封止動作について説明する。粘着液状態の封止剤６を塗布する線引き移動は、上記の状態において、図１の（ａ）に示すように、ノズル１をＩＣチップ２に対して相対的に移動走査して行い、ＩＣチップ２の上辺１１の一端Ａから他端Ｂまで移動しながら封止剤６を吐出して行う。場合によっては、ノズル１に対してステージ４を移動して線引きを行うようにしてもよい。以下の各実施形態においても同じである。なお、ノズル１の先端は、ＩＣチップの側面からは傾斜面方向に距離９だけ離れ、ＩＣ基板３からは法線方向に距離１０（図６（ｂ）に示す場合と同じである。）だけ離れている。
【００２７】
図１の（ｂ）に示すように、ノズル１から吐出圧力Ｐにより、適当な粘着液状態に調整された封止剤６がＩＣチップ２の上辺と基板２との間の隙間口近傍に吐出供給される。この封止剤６は、濡れ性（毛細管現象）及び自重により、時間の経過とともに次第にＩＣチップ２と基板３との間の隙間７を下方に流動していき、気泡の巻き込みを生じること無く、前記隙間７を充填する。なお、封止剤の塗布は、１回に限らず、ＩＣチップ２の大きさに応じて、必要十分な回数行う。
【００２８】
図２の（ａ）〜（ｇ）は、本発明の第１の実施形態におけるＩＣチップ封止方法の塗布回数が複数回の場合（この例では３回）の塗布方法と順序を示し、ＩＣチップ２と基板３との隙間７に封止剤が入っていく様子を，ＩＣチップ２を上から透視したと仮定して描いた概略図である。
【００２９】
塗布回数が、３回の場合、ＩＣチップ２の上の上辺から１回目の線引き塗布５１を行い（図２の（ａ））、塗布された封止剤がＩＣチップ２と基板３との隙間に入り込んでしまう状態５５になり、線引き箇所には基板３の表面に封止剤の残り跡５４ができる（図２の（ｂ））。その後２回目の線引き塗布５６を行う（図２の（ｃ））。１回目と同じように、塗布された封止剤がＩＣチップ２と基板３との隙間に入り込んでしまう状態５８になり、線引き箇所には基板３の表面に封止剤の残り跡５７ができる（図２の（ｄ））。その後３回目の線引き塗布５９を行う（図２の（ｅ））。塗布された封止剤がＩＣチップと基板との隙間に入り込みＩＣチップ２の下面全体を充填してしまう状態６０となり（図２の（ｆ））、さらにはＩＣチップ２の下辺から封止剤が露出する状態６２となる（図２の（ｇ））。なお、（ｇ）で示す状態６２においては、ＩＣチップ２の両側辺からはみ出した封止剤や線引き箇所の両端部から垂れ下った封止剤によって、フィレット６１が形成され、ＩＣチップ２の上下辺に形成されるフィレット６１と共に、ＩＣチップ２の４辺のいずれにもフィレット６１が形成される。
【００３０】
上記の封止方法によれば、封止剤６がＩＣチップ２の上面を覆うことはないので、ＩＣチップ２の放熱が要求された場合には、その上面に直接放熱板を取り付けることができ、また封止後の厚みをチップ厚み分のみの最小寸法にできるので、ＩＣチップの厚み方向に制約を受けた場合でも、問題は生じない。
【００３１】
また、基板３を傾け、ＩＣチップ２の上辺から封止剤６を線引き塗布するため、封止剤６が濡れ性だけでなく重力によって基板３とＩＣチップ２との間の隙間に入り込んで一方向（下方向）に流動していくので、気泡を巻き込む確率が低く、流れ込みを容易にすることができ、封止工程の時間短縮も容易に行うことができ、生産性も高めることができる。
【００３２】
なお、図１の（ｂ）において、１４はＩＣチップ２の下面に形成されたバンプ、１７は基板３の上面に形成された電極、１６は両者を接合する半田である。
【００３３】
（実施形態２）
図３は、本発明の第２の実施形態におけるＩＣチップの封止方法の斜視構成図である。
【００３４】
図３に示す第２の実施形態においては、図１の第１の実施形態と同様に、所定の角度に傾斜配置しかつ温度設定したステージ４上に、四角形状のＩＣチップ２の各辺を長方形基板３の対応する各辺に対し平行に配置して、ＩＣチップの上辺３３を長方形基板３の上辺３８に対し平行に配置して、封止を行う。
【００３５】
封止剤６の線引き移動は、ディスペンスノズル１をＩＣチップ２の上辺３３の一端Ａから他端Ｂまで移動しながら封止剤を吐出して行う。封止剤塗布回数はＩＣチップ２の大きさに応じて異なる。
【００３６】
第２の実施形態は、以上の点では第１の実施形態と基本的には同じであるが、ステージ４をその法線軸の回りに回転してＩＣチップの各辺ごとに線引き封止を行う点で第１の実施形態と異なる。
【００３７】
即ち、第２の実施形態においては、図３の（ａ）に示すように、ディスペンスノズル１を、ＩＣチップ２の上辺の一端Ａから他端Ｂまで線状に移動しながら、ＩＣチップ２及び基板に触れずに封止剤６を吐出した後或る時間の経過後、ステージ４を１８０°回転させ、新しく上辺に位置した辺（元の下辺）の端から他端まで移動しながら、ＩＣチップ２及び基板３に触れずに封止剤を吐出して線引きを行い、更に図３の（ｂ）に示すように、元の位置から９０°及び２７０°回転させた状態で、それぞれ封止剤を吐出して線引きを行う。このように、ステージ４を９０°単位で回転させ各辺を順次上辺に位置させて、それぞれ線引き塗布を行うことにより、フィレット形成に要する時間が短縮され、第１の実施形態よりも短時間で塗布することができ、生産性をより向上させることができる。
【００３８】
なお、上辺からの封止剤６の吐出供給と、ステージ４を１８０°回転させて元の下辺を上辺としての封止剤６の吐出供給との２工程のみで、封止を行ってもよい。
【００３９】
（実施形態３）
図４は、本発明の第３の実施形態におけるＩＣチップの封止方法の斜視構成図である。第３の実施形態は、図４の（ａ）に示すように、四角形状のＩＣチップ２を基板３上に装着した後、ＩＣチップ２と基板３との間の隙間を封止剤で封止する方法において、ステージ４上の基板３を水平面に対して所定角度αをもって傾斜させ、基板３の傾斜方向の基準線に対し、ほぼ４５°（β＝４５°）づつ傾斜するように上方左辺４２と上方右辺４３とが位置するようにＩＣチップ２を配置した状態で、ディスペンスノズル１をＩＣチップ２の上方左辺４２及び上方右辺４３に沿って相対的に移動させながら、ＩＣチップ２と基板３との間の隙間に、前記上方左辺４２及び上方右辺４３に沿った隙間口から粘着液状態の封止剤６を吐出供給することで封止を行っている。この際のディスペンスノズル１の移動軌跡を▲１▼、▲２▼で示す。このディスペンスノズル１による封止剤６の吐出供給は、ＩＣチップ２の下面全域が封止剤６で充填され、ＩＣチップ２の周辺にフィレットが形成されるまで繰り返し行われる。上記例では▲１▼、▲２▼で示す移動軌跡で封止剤６の吐出供給を繰り返し行ったが、図４の（ｂ）に示すような移動軌跡▲１▼、▲２▼、▲３▼、▲４▼、▲５▼、▲６▼で、封止剤６の吐出供給を行い、両側部に比較し、中央部の吐出供給量を大にすると合理的である。
【００４０】
なお、第３の実施形態のようにして、第１回目の封止剤６の吐出供給をおこなった後、基板３を１８０°回転させて、ＩＣチップの元の下方右辺及び下方左辺を前記上方左辺及び上方右辺に位置させた状態で上記と同様ディスペンスノズルから粘着液状態の封止剤を吐出供給することによって、封止作業を行うこともでき、このようにすることにより封止時間の短縮を図ることができる。
【００４１】
【発明の効果】
本発明によれば、ＩＣチップの上面に直接放熱板を取り付けることができ、またＩＣチップの厚みを最小寸法にできるよう、ＩＣチップの上面を覆うことなくＩＣチップの封止を行うことができる。
【００４２】
さらに、封止剤がその濡れ性だけでなく、自重により基板とＩＣチップとの隙間に流れ込んでいくので、流れ込みを容易にすることができ、時間短縮により生産性も高めることができると共に、気泡の巻き込みを抑える点で有利となる。
【図面の簡単な説明】
【図１】（ａ）は、本発明の第１の実施形態におけるＩＣチップの封止方法を示す斜視構成図である。
（ｂ）は、本発明の第１の実施形態におけるＩＣチップの封止方法を示す断面図である。
（ｃ）は、（ａ）、（ｂ）における基板とノズルの配置状態を示す図である。
【図２】本発明の第１の実施形態におけるＩＣチップの封止方法の塗布回数が複数回の場合の塗布方法と順序を示す図である。
【図３】（ａ）及び（ｂ）は本発明の第２の実施形態におけるＩＣチップの封止方法の斜視構成図である。
【図４】（ａ）は本発明の第３の実施形態におけるＩＣチップの封止方法の斜視構成図である。
（ｂ）はその変形例の吐出供給経路を示す図である。
【図５】（ａ）は従来例のＩＣチップの封止方法の斜視構成図である。
（ｂ）はその断面図である。
【図６】（ａ）は従来例のＩＣチップの封止方法の斜視構成図である。
（ｂ）はその断面図である。
【符号の説明】
１ディスペンスノズル
２１Ｃチップ
３基板
４ステージ
６封止剤[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flip chip mounting process and an MCM mounting process in IC mounting.
[0002]
[Prior art]
In recent years, the sealing process in the flip chip mounting process and the MCM (multichip module) mounting process in IC mounting is roughly divided into two types.
[0003]
The first method is generally performed as a method of sealing after mounting an IC chip, and is a method shown in FIGS. 5 (a) and 5 (b). In this method, an IC substrate 3 on which an IC chip 2 is flip-chiped (a method in which an IC chip whose output terminal is bumped on a protrusion is directly connected to a terminal of the substrate) is horizontally placed on a stage 4, and the dispensing nozzle 1 Is arranged so that the exit cross section thereof is parallel to the substrate, and the nozzle 1 is moved on the surface of the IC chip 2 and the sealing agent 6 is applied to cover the entire surface of the IC chip 2, for example, as shown by the movement locus L. Therefore, sealing is performed by the entry of the sealing agent 6 from the side surface. As the dispensing nozzle 1, the sealant 6 inside the container is sent to the output part of the container by a manual method, air pressure or pressure of a piston pump or an electric rotary screw, and the sealant 6 is discharged from the tip of the needle-like nozzle. Things are used.
[0004]
As shown in FIG. 6, the second method is that the dispensing nozzle 1 is not touched to the IC chip 2 and the substrate 3 from the outside of the side surface of the IC chip 2 flip-chiped without applying a sealant on the substrate 3. Further, a predetermined distance 9 from the IC chip 2 to the side and a predetermined distance 10 from the IC substrate 3 upward (a distance that is larger than the IC chip gap 7 and smaller than the total distance 8 of the IC chip thickness + IC chip gap). ) Is applied while the discharged sealant 6 is applied to the entire outer surface of the IC chip 2 while moving, so that the sealant 6 enters the gap 7 only by the wettability of the sealant 6. It is.
[0005]
[Problems to be solved by the invention]
However, in the first conventional method described above, since the sealing agent 6 also covers the upper surface of the IC chip 2, even when the heat dissipation of the IC chip 2 is required, it can be directly attached to the heat dissipation plate. Moreover, when the thickness of the IC chip 2 becomes large and is restricted in the thickness direction, it cannot be used.
[0006]
Further, in the conventional second method, in the case of the sealing agent 6 having a high viscosity, the sealing agent 6 cannot smoothly enter the gap 7 of the bump connection portion of the IC chip 2 due to the wettability alone. When there is a state in which bubbles are involved, and there is a high temperature (90 to 100 ° C.) process after the sealing step, the bump connection portion is often pressed by pressure due to the expansion of the bubbles, resulting in poor connection.
[0007]
The present invention solves the conventional problems as described above, and achieves a sealing effect accurately without inconvenience such as protrusion of the sealing agent on the IC chip surface and entrainment of bubbles in the gap of the connection part. An object of the present invention is to provide an IC chip sealing method that can be used.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the IC chip sealing method of the first invention of the present application is a method of sealing a gap between the IC chip and the substrate with a sealing agent after the IC chip is mounted on the substrate. In a state where the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane , the dispensing nozzle is kept so that the height position of the discharge port from the substrate is in the middle of the upper and lower surfaces of the IC chip. The adhesive nozzle is discharged and supplied from the gap opening along the upper side to the gap between the IC chip and the substrate while relatively moving along the upper side of the IC chip. It is characterized by filling the sealing agent in the adhesive liquid state between the IC chip and the substrate once or repeatedly.
[0009]
To achieve the above object, the IC chip sealing method of the second aspect of the present invention is the state in which the IC chip is tilted with 30 ° angle of less than 5 ° above the substrate mounted with respect to the horizontal plane, the IC In the gap between the chip and the substrate, the dispensing nozzle is relatively moved along the upper side of the IC chip, keeping the height of the discharge port from the substrate in the middle of the upper and lower surfaces of the IC chip. While discharging and supplying the sealing agent in the adhesive state from the gap opening along the upper side, and then rotating the substrate at a predetermined angle in a substantially horizontal plane, and tilting the substrate at a predetermined angle with respect to the horizontal plane, The sealing agent in the adhesive liquid state is supplied again in the same manner as described above.
[0010]
In order to achieve the above object, an IC chip sealing method according to a third invention of the present application is the method according to the second invention, wherein an adhesive is adhered to a gap between the IC chip and the substrate from a gap opening along the upper side of the IC chip. Discharge and supply liquid sealant, then rotate the substrate 180 ° in a substantially horizontal plane, tilt the substrate at a predetermined angle with respect to the horizontal plane, and re-discharge the adhesive sealant It is characterized by supplying.
[0011]
In order to achieve the above object, an IC chip sealing method according to a fourth invention of the present application is a method in which a gap between an IC chip and a substrate is sealed with a sealant after the IC chip is mounted on the substrate. When the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane, the upper left side and the upper right side are positioned so as to be inclined at a predetermined angle with respect to the reference line in the inclination direction of the substrate. With the IC chip disposed, the dispense nozzle is kept relative to the upper left side and the upper right side of the IC chip while maintaining the height position of the discharge port from the substrate in the middle of the upper and lower surfaces of the IC chip. The sealing agent in the adhesive liquid state is discharged and supplied to the gap between the IC chip and the substrate from the gap opening along the upper left side and the upper right side.
[0012]
In order to achieve the above object, an IC chip sealing method according to a fifth aspect of the present invention is the method according to the fourth aspect, wherein the substrate is tilted at a predetermined angle with respect to a horizontal plane, and substantially the reference line in the tilt direction of the substrate. a state where the upper side left and the upper side right so as to be inclined 45 ° increments placed the IC chip so as to be positioned, while relatively moving along the dispensing nozzle on side left and the upper side right of the IC chip , the gap between the IC chip and the substrate, and wherein the Rukoto discharge test teapot sealant adhesive liquid state from the gap outlet along the upper side left and the upper side right.
[0013]
In order to achieve the above object, an IC chip sealing method according to a sixth invention of the present application is the method according to the fifth invention, wherein an adhesive is provided between the IC chip and the substrate from a gap opening along the upper left side and the upper right side. The liquid sealant is discharged and supplied, and then the substrate is rotated by 180 ° in a substantially horizontal plane so that the original lower right side and lower left side of the IC chip are positioned on the upper left side and upper right side as above. It is characterized by discharging and supplying the sealing agent in the adhesive liquid state from the dispense nozzle. In each of the above inventions, it is desirable that the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane, and the substrate is disposed on a high-temperature stage.
[0014]
According to a first aspect of the present invention, the substrate is inclined at a predetermined angle to the horizontal plane, while relatively moving the de I dispense nozzle along the upper side of the IC chip, the gap between the IC chip and the substrate The adhesive liquid state sealant is discharged and supplied from the gap opening along the upper side, and the above-mentioned movement of the dispense nozzle is repeated to fill the adhesive liquid state sealant between the IC chip and the substrate . In other words, the IC substrate is installed with an inclination with respect to the horizontal plane, and the sealing agent is discharged while the nozzle is moved along the upper side of the IC chip. In addition, it can flow into the IC gap smoothly and in one direction due to its own weight, and the entrainment of bubbles can be suppressed as much as possible.
[0015]
Furthermore, since the sealing agent does not cover the IC surface, the IC surface can be directly attached to the heat dissipation plate when the heat dissipation of the IC is required. Since it is a dimension, it does not cause any trouble even when it is restricted in the thickness direction of the IC.
[0016]
The predetermined according to the second, third invention of the present application, after mounting the IC chip on the substrate, a method of sealing with a sealing agent the gap between the IC chip and the substrate, the substrate with respect to a horizontal plane is inclined at an angle, while relatively moving the de I dispense nozzle along the upper side of the IC chip, the gap between the IC chip and the substrate, the sealing agent of the adhesive liquid state from the gap opening along the upper edge Next, the substrate is rotated by a predetermined angle, for example, 180 ° in a substantially horizontal plane, and the sealing agent in the adhesive liquid state is discharged in the same manner as described above with the original lower side of the IC chip positioned at the upper side position. by supplying comparison, i.e., in a state that by rotating the IC chip is positioned opposing two sides, respectively to the upper side, since delineate coated perform sealing agent sealing agent along the upper side, in the first invention In terms of entrainment of bubbles Although it is inferior, productivity can be improved compared with this, distribution of sealing agent is made more equal, and a preferable sealing result can be obtained.
[0017]
Further, in the second invention of the present application, the dispense nozzle in a state where the substrate is inclined at a predetermined angle with respect to the horizontal plane and the IC chip is disposed so that the upper side and the lower side are positioned substantially perpendicular to the inclination direction of the substrate. Is relatively moved along the upper side of the IC chip, and the adhesive sealant is discharged and supplied from the gap opening along the upper side to the gap between the IC chip and the substrate. By rotating and discharging the adhesive sealant from the dispense nozzle in the same manner as described above with the original lower side, left side, and right side of the IC chip positioned at the upper side position, that is, the IC chip is rotated in 90-degree increments, while being positioned successively upper each side, it is possible to perform the drawing application of the sealant in each compared in this case the first invention, the bubble Inferior in terms of entanglement, but can be compared to sealing in a remarkably shorter period of time to this.
[0018]
The of the present application 4, according to the fifth aspect of the present invention, after mounting the IC chip on the substrate, a predetermined angle in a method of sealing, the substrate with respect to the horizontal plane of the gap between the IC chip and the substrate with a sealing agent With the IC chip disposed so that the upper left side and the upper right side are positioned at a predetermined angle, for example, approximately 45 ° with respect to the reference line in the tilt direction of the substrate, the dispense nozzle is set to the IC chip. while the upper side is relatively moved along the left side and the upper side right of, IC chip and the gap between the substrate, a sealing agent of the adhesive liquid state from the upper side left and the gap opening along the upper side right In other words, the two adjacent sides of the quadrilateral IC chip are positioned above the inclined surface on the inclined surface, and the drawing is applied almost simultaneously from the two sides, so that the number of applications is reduced and the efficiency is reduced in a short time. well Moreover, sealing can be performed without entrainment of bubbles.
[0019]
According to the sixth invention of the present application, by performing sealing from two adjacent sides inclined by 45 ° with respect to the reference line, which is newly positioned on the upper side by rotating the substrate by 180 degrees, the bubble is compared with the fifth invention. Although it is slightly inferior in terms of entrainment, sealing can be performed in a shorter time than this.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
FIG. 1 is a perspective configuration diagram (a), a cross-sectional view (b), and an arrangement state diagram of a substrate and a nozzle (c) of an IC chip sealing method according to a first embodiment of the present invention.
[0021]
First, the stage 4 for mounting the IC substrate 3 to be sealed is installed in a state inclined at a predetermined angle α with respect to the horizontal plane. Although the inclination angle α varies depending on the size of the IC chip 2 and the viscosity of the sealant 6, a predetermined angle of about 5 ° to 30 ° is preferable, and about 15 ° is optimal. This angle may be set to a fixed angle that is fixed during the sealing operation. In some cases, the inclination angle at the time of discharging the sealant and the inclination angle in the subsequent discharge agent flow period are set to the predetermined angle. Different values can be set within the range.
[0022]
Further, in order to lower the viscosity of the sealant 6 on the substrate 3, the temperature of the stage 4 is set to a certain constant temperature, and a temperature control means is provided for heating the substrate 3 to an appropriate temperature. Is preferred. This temperature varies depending on the type of the sealant 6, and may be 60 ° C., for example, but may sometimes be room temperature.
[0023]
Although not particularly shown above the stage 4, a mounting mechanism for mounting the IC substrate is provided. On the other hand, a rotating shaft oriented in the normal direction is provided on the lower surface side of the central portion of the stage 4, The stage 4 is configured to be able to rotate at an arbitrary angle within the inclined surface. The rotation shaft is configured to be driven and set at an arbitrary angle by a drive motor, a power source, and control means. The tilt angle of the stage 4 and thus the tilt angle of the rotating shaft may be adjustable and may be configured to be manually adjusted or changed by a predetermined program.
[0024]
On this stage 4, the IC chip 2 is flip-chiped in a state where the side 11 (for example, AB in the figure) of the rectangular IC chip 2 is arranged in parallel to the side 12 (for example, CD) of the rectangular substrate 3. The IC substrate 3 is held so that the relationship between the side 13 (for example, EF) of the stage 4 and the side 12 of the substrate 3 is parallel.
[0025]
As shown in FIG. 1 (c), the dispensing nozzle 1 is arranged so that its exit surface is parallel to the surface of the substrate 3. In this state, when the inclination angle α of the stage 4 with respect to the horizontal plane is 15 °, the angle between the horizontal plane and the axial direction of the nozzle is 75 °.
[0026]
Next, the sealing operation will be described. In the above state, the drawing movement for applying the sealant 6 in the adhesive liquid state is performed by moving and scanning the nozzle 1 relative to the IC chip 2 as shown in FIG. The sealant 6 is discharged while moving from one end A to the other end B of the upper side 11 of the chip 2. In some cases, drawing may be performed by moving the stage 4 relative to the nozzle 1. The same applies to the following embodiments. It should be noted that the tip of the nozzle 1 is separated from the side surface of the IC chip by a distance 9 in the inclined surface direction, and from the IC substrate 3 by a distance 10 in the normal direction (same as shown in FIG. 6B). is seperated.
[0027]
As shown in FIG. 1B, the sealant 6 adjusted to an appropriate pressure-sensitive adhesive state by the discharge pressure P from the nozzle 1 is discharged near the gap opening between the upper side of the IC chip 2 and the substrate 2. Supplied. This sealant 6 gradually flows downward through the gap 7 between the IC chip 2 and the substrate 3 with the passage of time due to wettability (capillary phenomenon) and its own weight, without causing entrainment of bubbles, The gap 7 is filled. The sealing agent is applied not only once but also a necessary and sufficient number of times depending on the size of the IC chip 2.
[0028]
FIGS. 2A to 2G show the application method and order when the IC chip sealing method according to the first embodiment of the present invention is applied a plurality of times (in this example, 3 times). FIG. 5 is a schematic diagram illustrating that the sealing agent enters the gap 7 between the chip 2 and the substrate 3 on the assumption that the IC chip 2 is seen through from above.
[0029]
When the number of times of application is 3, the first draw application 51 is performed from the upper side of the IC chip 2 ((a) in FIG. 2), and the applied sealing agent is a gap between the IC chip 2 and the substrate 3. It enters the state 55 where it enters, and a trace 54 of the sealant is formed on the surface of the substrate 3 at the drawing position ((b) of FIG. 2). Thereafter, the second drawing 56 is performed ((c) in FIG. 2). As in the first time, the applied sealing agent enters a state 58 where it enters the gap between the IC chip 2 and the substrate 3, and a trace 57 of the sealing agent is formed on the surface of the substrate 3 at the drawing point. ((D) of FIG. 2). Thereafter, a third drawing application 59 is performed ((e) in FIG. 2). The applied sealing agent enters the gap between the IC chip and the substrate and fills the entire lower surface of the IC chip 2 ((f) in FIG. 2). Further, the sealing agent starts from the lower side of the IC chip 2. Is exposed 62 ((g) of FIG. 2). In the state 62 shown in (g), the fillet 61 is formed by the sealant that protrudes from both sides of the IC chip 2 or the sealant that hangs down from both ends of the drawing portion, and the top and bottom of the IC chip 2. Together with the fillet 61 formed on the side, the fillet 61 is formed on any of the four sides of the IC chip 2.
[0030]
According to the above sealing method, since the sealing agent 6 does not cover the upper surface of the IC chip 2, when heat dissipation of the IC chip 2 is required, a heat radiating plate can be directly attached to the upper surface. In addition, since the thickness after sealing can be set to the minimum dimension corresponding to the chip thickness, no problem occurs even when the thickness direction of the IC chip is restricted.
[0031]
Further, since the substrate 3 is tilted and the sealing agent 6 is drawn and applied from the upper side of the IC chip 2, the sealing agent 6 enters the gap between the substrate 3 and the IC chip 2 not only by wettability but also by gravity. Since it flows in the direction (downward), the probability of entraining bubbles is low, the flow can be facilitated, the time required for the sealing process can be easily reduced, and the productivity can be increased.
[0032]
In FIG. 1B, 14 is a bump formed on the lower surface of the IC chip 2, 17 is an electrode formed on the upper surface of the substrate 3, and 16 is solder for joining the two.
[0033]
(Embodiment 2)
FIG. 3 is a perspective configuration diagram of an IC chip sealing method according to the second embodiment of the present invention.
[0034]
In the second embodiment shown in FIG. 3, as in the first embodiment of FIG. 1, each side of the rectangular IC chip 2 is placed on a stage 4 that is inclined at a predetermined angle and set at a temperature. Sealing is performed by arranging parallel to the corresponding sides of the rectangular substrate 3 and arranging the upper side 33 of the IC chip parallel to the upper side 38 of the rectangular substrate 3.
[0035]
The drawing movement of the sealing agent 6 is performed by discharging the sealing agent while moving the dispensing nozzle 1 from one end A to the other end B of the upper side 33 of the IC chip 2. The number of times of applying the sealant varies depending on the size of the IC chip 2.
[0036]
The second embodiment is basically the same as the first embodiment in the above points, but the stage 4 is rotated around its normal axis to draw and seal each side of the IC chip. This is different from the first embodiment.
[0037]
That is, in the second embodiment, as shown in FIG. 3A, the dispensing nozzle 1 is moved linearly from one end A to the other end B on the upper side of the IC chip 2, and the IC chip 2 and After a certain period of time has passed since the sealant 6 was discharged without touching the substrate, the stage 4 was rotated 180 ° and moved from the end of the side (original lower side) newly located on the upper side to the other end. Drawing is performed by discharging the sealing agent without touching the chip 2 and the substrate 3, and further sealing is performed in a state rotated by 90 ° and 270 ° from the original position as shown in FIG. The agent is discharged to draw the line. In this way, by rotating the stage 4 in units of 90 °, each side is sequentially positioned on the upper side, and performing each drawing application, the time required for fillet formation is shortened, and in a shorter time than in the first embodiment. It can apply | coat and can improve productivity more.
[0038]
The sealing may be performed only in two steps, that is, the discharge supply of the sealing agent 6 from the upper side and the discharge supply of the sealing agent 6 with the original lower side as the upper side by rotating the stage 4 by 180 °. .
[0039]
(Embodiment 3)
FIG. 4 is a perspective configuration diagram of an IC chip sealing method according to the third embodiment of the present invention. In the third embodiment, as shown in FIG. 4A, after mounting the rectangular IC chip 2 on the substrate 3, the gap between the IC chip 2 and the substrate 3 is sealed with a sealing agent. a method of sealing, is inclined at a predetermined angle α with the substrate 3 on the stage 4 with respect to the horizontal plane, with respect to the reference line in the inclination direction of the substrate 3, lateral upper so as to be inclined at a time approximately 45 ° (β = 45 °) in a state in which the left side 42 and the upper side right 43 placed the IC chip 2 so as to be positioned, while relatively moving along the dispensing nozzle 1 on side left 42 and the upper side right 43 of the IC chip 2, IC the gap between the chip 2 and the substrate 3, are carried out sealing by discharging supplying sealant 6 of the adhesive liquid state from the upper side left 42 and gap opening along the upper side right 43. The movement trajectory of the dispensing nozzle 1 at this time is indicated by (1) and (2). The discharge supply of the sealing agent 6 by the dispensing nozzle 1 is repeated until the entire lower surface of the IC chip 2 is filled with the sealing agent 6 and a fillet is formed around the IC chip 2. In the above example, the discharge and supply of the sealing agent 6 were repeatedly performed along the movement trajectories indicated by (1) and (2). However, the movement trajectories (1), (2), and (3) as shown in FIG. It is reasonable to supply the sealant 6 at ▼, ▲ 4, ▲ 5, and ⑥, and to increase the discharge supply amount at the center compared to both sides.
[0040]
Incidentally, as in the third embodiment, after subjected to discharge supply of the first sealant 6, the substrate 3 is rotated 180 °, the original lower side right side and the lower side left in the IC chip sealed by by discharging supplying sealant adhesive liquid state from the same dispensing nozzle in a state of being positioned in the upper side left and the upper side right, can also do the sealing operation, to such The stop time can be shortened.
[0041]
【The invention's effect】
According to the present invention, the heat sink can be directly attached to the upper surface of the IC chip, and the IC chip can be sealed without covering the upper surface of the IC chip so that the thickness of the IC chip can be minimized. .
[0042]
Furthermore, since the sealant flows not only in its wettability but also into the gap between the substrate and the IC chip due to its own weight, the flow can be facilitated, and the productivity can be improved by shortening the time. This is advantageous in terms of suppressing the entrainment of.
[Brief description of the drawings]
FIG. 1A is a perspective configuration diagram illustrating an IC chip sealing method according to a first embodiment of the present invention.
(B) is sectional drawing which shows the sealing method of the IC chip in the 1st Embodiment of this invention.
(C) is a figure which shows the arrangement | positioning state of the board | substrate and nozzle in (a), (b).
FIG. 2 is a diagram showing a coating method and order when the number of times of coating in the IC chip sealing method according to the first embodiment of the present invention is plural.
FIGS. 3A and 3B are perspective configuration diagrams of an IC chip sealing method according to a second embodiment of the present invention. FIGS.
FIG. 4A is a perspective configuration diagram of an IC chip sealing method according to a third embodiment of the present invention.
(B) is a figure which shows the discharge supply path | route of the modification.
FIG. 5A is a perspective configuration diagram of a conventional IC chip sealing method.
(B) is a sectional view thereof.
6A is a perspective configuration diagram of a conventional IC chip sealing method. FIG.
(B) is a sectional view thereof.
[Explanation of symbols]
1 Dispensing nozzle 2 1C chip 3 Substrate 4 Stage 6 Sealant

Claims

In the method of sealing the gap between the IC chip and the substrate with a sealant after mounting the IC chip on the substrate, the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane . The dispense nozzle is kept relatively high along the upper side of the IC chip while keeping the height of the discharge port from the substrate in the middle of the upper and lower surfaces of the IC chip. A sealant in the adhesive liquid state is discharged and supplied to the gap between the gaps along the upper side, and the above movement of the dispense nozzle is performed once or repeatedly to seal the adhesive liquid state between the IC chip and the substrate. An IC chip sealing method comprising filling a stopper.

In a state where the substrate on which the IC chip is mounted is inclined at an angle of 5 ° or more and 30 ° or less with respect to the horizontal plane, a dispense nozzle is inserted into the gap between the IC chip and the substrate from the substrate of the discharge port. While keeping the height position in the middle of the upper and lower surfaces of the IC chip, the adhesive liquid state sealant is discharged and supplied from the gap opening along the upper side while moving relatively along the upper side of the IC chip. Then, the substrate is rotated by a predetermined angle within a substantially horizontal plane, and the substrate is inclined at a predetermined angle with respect to the horizontal plane, and the adhesive in the adhesive liquid state is re-discharged and supplied in the same manner as described above. IC chip sealing method.

In the gap between the IC chip and the substrate, the adhesive in the state of the adhesive liquid is discharged and supplied from the gap opening along the upper side of the IC chip, and then the substrate is rotated by 180 ° in a substantially horizontal plane, and 3. The IC chip sealing method according to claim 2 , wherein the adhesive in the state of the adhesive liquid is re-discharged and supplied in a state where the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane. .

In the method of sealing the gap between the IC chip and the substrate with a sealant after mounting the IC chip on the substrate, the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane . In the state where the IC chip is arranged so that the upper left side and the upper right side are positioned at a predetermined angle with respect to the reference line in the substrate tilt direction, the height of the discharge nozzle from the substrate is set. While maintaining the position between the upper and lower surfaces of the IC chip and relatively moving along the upper left side and the upper right side of the IC chip, the upper left side and the upper side are inserted into the gap between the IC chip and the substrate. A method for sealing an IC chip, comprising discharging and supplying a sealing agent in an adhesive state from a gap opening along the right side.

When the substrate is inclined at an angle of 5 ° to 30 ° with respect to the horizontal plane, the upper left side and the upper right side are positioned so as to be inclined by about 45 ° with respect to the reference line in the inclination direction of the substrate. While the IC chip is disposed, the dispensing nozzle is moved relatively along the upper left side and the upper right side of the IC chip, and the gap between the IC chip and the substrate is spaced along the upper left side and the upper right side. 5. The IC chip sealing method according to claim 4, wherein a sealing agent in an adhesive liquid state is discharged and supplied from the mouth.

Between the IC chip and the substrate, a sealant in an adhesive liquid state is discharged and supplied from a gap opening along the upper left side and the upper right side, and then the substrate is rotated by 180 ° in a substantially horizontal plane, 6. The IC chip according to claim 5, wherein an adhesive liquid-like sealant is discharged and supplied from a dispense nozzle in the same manner as described above with the original lower right side and lower left side being located on the upper left side and upper right side. Sealing method.

Claim 2, 3, 4, 5 or 6 IC chip sealing method according to placing a substrate on a stage of the high-temperature state.