JP3883287B2

JP3883287B2 - Component mounting method and apparatus

Info

Publication number: JP3883287B2
Application number: JP09861498A
Authority: JP
Inventors: 治人永田
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1998-04-10
Filing date: 1998-04-10
Publication date: 2007-02-21
Anticipated expiration: 2018-04-10
Also published as: JPH11297756A

Description

【０００１】
【発明の属する技術分野】
本発明は、部品の実装方法およびその装置に関し、特に、ペースト状の接合材料を用いて部品と基板とを接合して双方を電気接続するフリップチップ実装方式を採用した部品の実装方法およびその装置に関するものである。
【０００２】
【従来の技術】
従来、ベアＩＣチップを回路基板上にフリップチップ実装するのに、接合材料は基板の側に供給している。例えば図５の（ａ）に示すように、専用の塗布装置ａを用いて、基板ｂのベアＩＣチップｃを実装する位置に、接合材料ｄをディスペンサｅなどによって供給する。接合材料ｄを塗布した基板ｂは図５の（ｂ）に示す各種の搬送過程を経て図５の（ｃ）に示す部品実装装置ｆへ移される。部品実装装置ｆでは部品供給部で供給されるＩＣチップｃを吸着ノズルｊにより吸着保持して、実装位置に位置決めされる基板ｂの上に持ち運び、ＩＣチップｃの実装面ｃ１を基板ｂの接合材料ｄが供給されている所定位置に当てがって、ＩＣチップｃと基板ｂとを接合材料ｄにより接合して双方を電気接続状態とし、通常接合材料ｄは加熱や光照射によって硬化される。
【０００３】
基板ｂにはＩＣチップｃとの電気接続を行う図６の（ｂ）に示すような電極パターンｇなどがあり、接合材料ｄを介した接合によってＩＣチップｃの実装面ｃ１に設けた金属バンプｈとの接触が図られる。
【０００４】
ところで、基板ｂには多数のＩＣチップｃをフリップチップ実装するのが普通で、前記塗布装置ａでは基板ｂのＩＣチップｃを実装する多数の位置に接合材料ｄを予め供給しておくことになる。
【０００５】
しかし、硬化前の接合材料ｄに十分な接合力はなく、ＩＣチップｃを基板ｂに押し当てたまま接合材料ｄを硬化しないと、ＩＣチップｃに浮きが生じ電気接続が不良となる。
【０００６】
そこで、部品実装装置ｆでは基板ｂの接合材料ｄが供給されている複数の位置にＩＣチップｃを前記のように接合材料ｄの硬化操作を伴い順次にフリップチップ実装していくのに、未実装位置の接合材料ｄが、雰囲気温度やＩＣを実装している位置での硬化操作の影響を受けてＩＣチップｃが当てがわれる前に硬化してしまうようなことがないように配慮される。
【０００７】
【発明が解決しようとする課題】
一方、近時では電子部品の小型化および実装の高密度化の要求が強くなってきている。これに対応するのに、上記従来のフリップチップ実装方法では、接合材料ｄが図６の（ａ）（ｂ）に示すようにＩＣチップｃのまわりに拡がることが問題となってきた。接合材料ｄがＩＣチップｃまわりに拡がると、高密度実装のためにＩＣチップｃの実装間隔を例えば１ｍｍ程度まで小さくしようとすると、図６の（ａ）（ｂ）に示すＩＣチップｃの実装において、ＩＣチップｃのまわりに拡がる接合材料ｄが隣接する仮想線で示すＩＣチップｃの実装位置にある電極パターンｇの上に被さって硬化されてしまう。従って、その隣接位置に次のＩＣチップｃを実装するとき、電極パターンｇとＩＣチップｃの金属バンプｈとの接触を妨げ、電気接続が不安定になったり、接続不良を招いたりし、製品の品質や歩留りが低下する。
【０００８】
接合材料ｄはディスペンサｅにより基板ｂの上に図５の（ａ）に示すように供給するが、供給後にディスペンサｅを基板ｂから引き離したとき、基板ｂ上に供給された接合材料ｄは最初、図５の（ａ）に仮想線で示すように盛り上がっているが、その後基板ｂとのぬれ性や自身の表面張力などの関係で図５の（ｂ）に示すようにまわりに拡がりかさ低くなる。
【０００９】
図５の（ａ）に仮想線で示す接合材料ｄの大きさと、図５の（ｂ）に示す接合材料ｄの大きさとの間には一定の関係があり、接合材料ｄの拡がり後の大きさは制御できる。しかし、拡がり後の接合材料ｄのかさが低すぎると、基板ｂの接合材料ｄが供給された上にＩＣチップｃを当てがうとき、ＩＣチップｃの実装面ｃ１に金属バンプｈなどの電気接続を行う突起があって、実装面ｃ１と基板ｂとの間に浮きができる場合は特に、実装面ｃ１と基板ｂとの間が接合材料ｄで埋まり切らず接合不良となって、電気接続に溶融固化する半田バンプを用いない場合は特に、電気接続の不良、不能状態、ＩＣチップｃのガタツキや脱落などを招きやすい。
【００１０】
接合材料ｄの粘度を上げて拡がりを抑えようとすると、基板ｂに接合材料ｄをディスペンサｅで供給して後、これを基板ｂから引き離すときの糸引きによって基板ｂを汚損し不良品化してしまうという問題が生じるので、これも、接合材料ｄの拡がりを規制するには限界があって十分には抑え切れない。
【００１１】
従って、従来、接合材料ｄをディスペンサｅにより基板ｂの上に供給するのに、接合不良を回避できるだけの接合材料ｄの供給かさを確保することを第１として、先ずこれに留意し、接合材料ｄの拡がりは二の次になっている。この結果、使用する接合材料ｄの粘度を狭い範囲に抑えながらも、接合材料ｄのＩＣチップｃまわりへの拡がりの問題は解決できていない。
【００１２】
本発明者らは、接合材料の新たな供給方式につき、種々に実験をしたところ、部品の実装面に接合材料を供給して基板との接合を行うと、接合材料の部品まわりへの拡がりを抑制できることを知見した。
【００１３】
本発明の目的は、このような新たな知見に基づき、高密度化に対応できる部品の実装方法およびその装置を提供することにある。
【００１４】
【課題を解決するための手段】
上記のような目的を達成するため、本発明の請求項１に係る部品の実装方法は、第１に、ペースト状の接合材料を用いて部品と基板とを接合して相互の電気接続を行いフリップチップ実装するのに、部品の実装面側に供給した接合材料によって、部品と基板とを接合して部品と基板の電気接続を行いフリップチップ実装するのに、部品と基板との接合材料による接合に際し接合材料を硬化させる硬化操作を行い、１つの硬化操作として、基板を、部品を当てがう前から加熱しておき加熱源とすることを特徴としている。
【００１５】
このように、部品の実装面側に接合材料を供給すると、供給した接合材料は実装面が上に向いていても部品の側周面にまわり込みにくく、接合材料のかさを十分な自由度で設定でき、実装面が下向きであると供給した接合材料は部品の側周面にさらにまわり込みにくく、接合材料の供給かさの十分な設定自由度が幅広い粘度域にて達成することができる。このように部品の側周面へのまわり込み防止と供給かさの適正な設定をもって接合材料を供給した部品の実装面を基板に当てがって部品と基板とを接合すると、実装面に金属バンプなどの電気接続突起がある場合でも、部品と基板との間を接合材料で十分に埋め切って確実な接合およびそれによる電気接続を図りながら、接合材料が部品のまわりに拡がる量および大きさを所定範囲内に規制することができ、各種の電子部品をフリップチップ実装して電子回路基板などを製造するときの高密度実装の要求に対応することができる。
また、部品と基板との接合材料による接合に際し、接合材料を加熱または／および光によって硬化させる硬化操作を行うと、部品を基板に当てがって電気接続させた状態に固定することができ、電気接続不良が接合のあと事後的に発生するのを防止できる。１つの硬化操作として、基板を、部品を当てがう前から加熱しておいて加熱源とすると、接合材料が供給された部品を基板に当てがった時点から、基板が所定温度での加熱源となって即時に加熱が開始されるので、加熱源の温度の立ち上がりのための時間が不要となり硬化操作が短時間に達成され、作業能率が向上する。採用できる接合材料には導電粒子を含まないものや、導電粒子を均一に分散させた異方性導電ペーストがある。後者のものは接合材料自体に導電粒子による導電性はないが、部品を基板に当てがったときの双方の電気接続部間に接合材料中の導電粒子が介在して双方の電気接続を補助するので、部品と基板との接合による電気接続性を向上することができ、製品の品質の安定を図ることができる。
【００１７】
この場合、部品の実装面と貯留された接合材料の表面とを近づけていって接合材料を部品の実装面に付着させた後、双方を引き離して接合材料の供給を終えるようにすると、接合材料の供給操作が簡単で容易かつ短時間に達成できる利点があるし、部品の実装面と接合材料表面との近づけ状態や接合材料の粘度によって接合材料の供給かさを十分な自由度で設定することができるので、上記の方法をより有利に達成することができる。
【００１９】
上記のような部品を一連に取り扱っての基板への実装方法は、部品を供給する部品供給部と、ペースト状の接合材料を貯留する貯留部と、基板を部品との接合位置に位置決め保持し接合作業に供する基板保持手段と、部品供給部で供給される部品を部品取り扱いツールにより保持して貯留部の接合材料上に持ち運んで、その表面に部品の実装面を近づけて行って接合材料を付着させた後双方を引き離し、その部品を基板保持手段により接合位置に位置決めされている基板の上に持ち運んでその所定位置に実装面を当てがい、部品と基板とを接合することを繰り返し行う部品実装ヘッドと、部品取り扱いツールまたは部品取り扱いツールが保持している部品と貯留された接合材料の表面との間の距離を計測する計測手段と、この計測手段により計測された計測情報を基に取り扱いツールが保持している部品を接合材料に近づける位置を制御する制御手段とを備えた部品の実装装置によって、部品の供給をも含めて、一定のプログラムに従い自動的に確実に能率よく達成することができる。
【００２０】
特に、この装置に備える、部品取り扱いツールまたは部品取り扱いツールが保持している部品と貯留された接合材料の表面との間の距離を計測する計測手段と、この計測手段により計測された計測情報を基に取り扱いツールが保持している部品を接合材料に近づける位置を制御する制御手段とによって、貯留している接合材料の表面位置を一定に保たなくても、部品の実装面を接合材料の表面に近づける作業の都度、接合材料の表面と部品取り扱いツールや部品との間の距離の計測手段による計測情報に基づき、制御手段が部品の実装面を接合材料の表面に近づける位置を制御するので、部品の実装面への接合材料の付着域および付着かさを設定通りに制御することができ、接合材料の部品まわりへの拡がりを所定範囲内に規制しての確実な部品のフリップチップ実装を安定して達成することができる。
【００２１】
【発明の実施の形態】
以下、本発明に係る部品の実装方法およびその装置の実施の形態について、図を参照しながら説明する。
【００２２】
本実施の形態の部品の実装方法は、図１に示すようにペースト状の接合材料１５を用いてチップ形の電子部品、特にベアＩＣなどであるＩＣチップ１２を実装対象部品とし、部品を実装する基板の一例としての回路基板１６にそのＩＣチップ１２をフリップ実装する場合の一例である。図１に示す部品実装装置を参照しながら説明すると、ＩＣチップ１２と回路基板１６とを図１の（ｃ）、図３の（ｂ）に示すように接合して相互の電気接続を行いフリップチップ実装するのに、図１の（ｂ）（ｃ′）に示すようにＩＣチップ１２の実装面１２ａ側に供給した接合材料１５によって、ＩＣチップ１２と回路基板１６とを図１の（ｃ）に示すように接合してＩＣチップ１２と回路基板１６の図３の（ｂ）に示すような電気接続を行いフリップチップ実装する。
【００２３】
このようなフリップチップ実装のために、ＩＣチップ１２の実装面１２ａと回路基板１６とには、それぞれが担持している回路パターンなどを接続し合う電気接続部が設けられている。電気接続部は通常、回路基板１６側が回路パターンなどの一部である図３の（ｂ）に示すような電極パターン１６ａとされ、ＩＣチップ１２側は回路パターンなどの電極部に設けたバンプ１２ｂとされる。バンプ１２ｂはそれ自身の溶融硬化によってＩＣチップ１２と回路基板１６との電気接続を行う半田バンプと、溶融を伴わずＩＣチップ１２と回路基板１６との電気接続を行う金などよりなる金属バンプとがある。本発明の部品実装方法はそのいずれにも適用できる。しかし、前記接合材料１５の部品まわりへの拡がりが問題になりやすい金属バンプの場合に、本発明は特に有効であり、この場合についてだけ以下述べる。
【００２４】
上記のように、ＩＣチップ１２の実装面１２ａ側に接合材料１５を供給すると、供給した接合材料１５は実装面１２ａが上に向いていても自身の表面張力やぬれ性などによってＩＣチップ１２の側周面１２ｃにまわり込みにくく、接合材料１５の供給かさを十分な自由度で設定できるが、特に、実装面１２ａが図１、図２に示すように下向きであると、供給した接合材料１５は重力の作用も手伝ってＩＣチップ１２の側周面１２ｃにさらにまわり込みにくくなり、実装面１２ａの中央部に接合材料１５が安息角一杯に集まって垂れ下がる現象から、接合材料１５の供給かさの設定が十分な自由度で、かつ幅広い粘度域にて達成することができる。このような特徴は、接合材料１５をディスペンサなどにより手動であるいは自動で供給するいずれの場合も同様であるし、接合材料１５の供給方法の違いによらずほぼ共通している。
【００２５】
このように接合材料１５のＩＣチップ１２の側周面１２ｃへのまわり込み防止と供給かさの適正な設定をもって、接合材料１５を供給したＩＣチップ１２の実装面１２ａを図１の（ｃ）に示すように回路基板１６に当てがってＩＣチップ１２と回路基板１６とを接合すると、実装面１２ａにバンプ１２ｂなどの電気接続用の突起がある場合でも、ＩＣチップ１２と回路基板１６との間を図３の（ｂ）に示すように接合材料１５で十分に埋め切って確実な接合およびそれによる電気接続を図りながら、接合材料１５がＩＣチップ１２のまわりに拡がる量および大きさを図３の（ａ）（ｂ）に示すような所定範囲内に規制することができる。
【００２６】
これによって、図３の（ｂ）に実線で示すＩＣチップ１２のフリップチップ実装に当たって用いた接合材料１５が、高密度実装したい仮想線で示す他のＩＣチップ１２のフリップチップ実装によって電気接続すべき電極パターン１６ａを覆うことはなく、実線のＩＣチップ１２のフリップチップ実装に用いた接合材料１５が前記仮想線の隣接ＩＣチップ１２のフリップチップ実装の前に硬化されても、隣接ＩＣチップ１２のフリップチップ実装を妨げることはない。従って、各種の電子部品をフリップチップ実装して電子回路基板などを製造するときの高密度実装の要求に対応することができる。
【００２７】
ＩＣチップ１２と回路基板１６との接合材料１５による接合に際し、通常、接合材料１５は硬化させるが、これは加熱または／および光による硬化操作で行われ、ＩＣチップ１２を回路基板１６に当てがって接合し電気接続させた状態を固定することができ、電気接続不良が事後的に発生するのを防止できる。１つの硬化操作として、本実施の形態では回路基板１６を、ＩＣチップ１２を当てがう前からヒータ１８などで加熱しておいて加熱源としている。これにより、図１の（ｃ′）に示すように接合材料１５が供給されたＩＣチップ１２を、図１の（ｃ）に示すように回路基板１６に当てがった時点から、回路基板１６が所定温度の加熱源となって即時に加熱が開始されるので、加熱源の温度の立ち上がりのための時間が不要となり硬化操作が短時間に達成され、作業能率が向上する。
【００２８】
ペースト状の接合材料は、一般には加熱併用紫外線硬化形先着材が用いられる。これには液状のエポキシアクリレート樹脂を主成分とするものがある。増粘剤の添加割合によって粘度が自由に設定できる。もっとも、本発明の方法を達成できるものであれば、他の既に知られ、また、新しく提供されるどのような接着剤、接合材料を用いることもできる。
【００２９】
接合材料１５にはさらに、導電粒子を含まないものや、導電粒子を均一に分散させた異方性導電ペーストがあり、そのいずれをも採用することはできる。しかし、特に後者のもは接合材料１５自体に導電粒子による導電性はないが、ＩＣチップ１２を図１の（ｃ）に示すように回路基板１６に当てがったときの双方の電気接続部である図３の（ｂ）に示すバンプ１２ｂおよび電極パターン１６ａ間に接合材料１５中の図示しない導電粒子が介在して双方の電気接続を補助するので、ＩＣチップ１２と回路基板１６との接合による電気接続性を向上することができ、ＩＣチップ１２などの電子部品を実装して製造される電子回路基板などの製品の品質の安定を図ることができる。
【００３０】
本実施の形態の部品の実装方法は特に、ＩＣチップ１２の実装面１２ａと、接着剤槽１４に貯留されるなどした接合材料１５の表面１５ａとを、図１の（ｂ′）から図１の（ｂ）に示すように近づけていって、接合材料１５をＩＣチップ１２の実装面１２ａに付着させた後、双方を引き離して接合材料１５の実装面１２ａへの供給を終えるようにする。これにより、接合材料１５の供給操作が簡単で容易かつ短時間に達成できる利点があるし、ＩＣチップ１２の実装面１２ａと接合材料表面１５ａとの近づけ状態や接合材料１５の粘度によって接合材料１５の供給かさを十分な自由度で設定することができ、上記の部品の実装方法をより有利に達成することができる。
【００３１】
しかも、このような部品の実装方法を採用するのに、本実施の形態では図１に示すように、部品供給部１１のＩＣチップ１２を部品取り扱いツールの一例としての吸着ノズル１３により吸着して保持し、貯留された接合材料１５上に持ち運び、ＩＣチップ１２の実装面１２ａを近づけていって接合材料１５を付着させた後双方を引き離して接合材料１５をＩＣチップ１２の実装面１２ａ付着させるのに続き、接合材料１５付着後のＩＣチップ１２を回路基板１６上に持ち運んでその実装面１２ａを回路基板１６の所定位置に当てがいＩＣチップ１２と回路基板１６とを接合して相互の電気接続を行いフリップチップ実装するようにする。
【００３２】
これにより、ＩＣチップ１２を部品取り扱いツールである吸着ノズル１３によって保持したままの一連の取り扱いにより、そのＩＣチップ１２の実装面１２ａへの接合材料１５の供給と、この供給した接合材料１５によるＩＣチップ１２と回路基板１６との接合およびそれによる電気接続を達成することができ、実装作業の全体が簡単になり容易かつ短時間で達成される利点がある。
【００３３】
上記のようにＩＣチップ１２などの各種部品を一連に取り扱い、回路基板１６などの基板に実装する方法を実現するのに、図１に示す部品の実装装置は、前記した、ＩＣチップ１２などの部品を部品供給位置２０に供給する部品供給部１１、ペースト状の接合材料１５を接合材料供給位置２１に貯留しておく貯留部の一例としての接着剤槽１４、ＩＣチップ１２を保持して各種に取り扱う部品取り扱いツールの一例としての吸着ノズル１３などの他に、回路基板１６をＩＣチップ１２との図１に示す接合位置２２に位置決め保持して前記接合、接続作業に供する基板保持手段１７と、部品供給位置２０にて部品供給部１１から供給されるＩＣチップ１２を吸着ノズル１３により保持して、接合材料供給位置２１に移動し接着剤槽１４に貯留されている接着剤槽１４上にＩＣチップ１２を持ち運んで、その表面１５ａにＩＣチップ１２の実装面１２ａを近づけていって接合材料１５を付着させた後、双方を引き離し、この接合材料１５付着後のＩＣチップ１２を、接合位置２２に位置決めされている回路基板１６の上に持ち運んでその所定位置に実装面１２ａを当てがい、ＩＣチップ１２と回路基板１６とを接合して電気接続を行うことを繰り返し行う部品実装ヘッド２３とを備え、それらの各手段をマイクロコンピュータや他の電気回路などを用いた制御装置２４により、内部のあるいは外部の各種記憶手段２４ａに記憶された一定のプログラムに従って動作制御し、前記のようにＩＣチップ１２を吸着ノズル１３によって一連に取り扱って回路基板１６にフリップチップ実装する方法を、ＩＣチップ１２などの部品の供給をも含めて、自動的に確実に能率よく達成することができる。
【００３４】
部品供給部１１はフリップチップ実装する各種のＩＣチップ１２、あるいは他の方式を複合して実装される電子部品を含め、その都度必要とされるものを供給するために、例えばトレー２５に収納した部品を取り扱う。必要な部品を収納したトレー２５をトレー搬送手段２７のモータ２８による正転駆動にて部品供給位置２０に移動させて、そのトレー２５に収納しているＩＣチップ１２などの部品を実装に供する。次に供給すべきＩＣチップ１２などが別のものであると、部品供給位置２０にあるトレー２５をトレー搬送手段２７のモータ２８の逆転駆動により基に戻して格納した後、次に必要なＩＣチップ１２などを収納したトレー２５を部品供給位置２０に移動させて部品を供給することを繰り返す。しかし、ＩＣチップ１２などの各種の部品を供給するのに、その部品の種類に応じた既に知られる各種の方式を採用することができる。
【００３５】
部品取り扱いツールは吸着ノズル１３に限られることはなく、部品を挟み持つチャックタイプのもの、部品と接続される接続タイプのものなど、取り扱う部品の種類に応じた各種のものを採用でき、場合によっては同種のものを複数、あるいは異種のものを複合して装備し、選択使用するようにもできる。
【００３６】
基板保持手段１７はこれに対して回路基板１６をモータ３３の正転駆動により搬入してＩＣチップ１２などの実装に供し、必要な部品の実装が終了した回路基板１６をモータ３３のさらなる正転駆動により先へ搬出する搬送手段２９と組合せ用いられる。基板保持手段１７は、搬入された回路基板１６を例えば図のＸ方向と紙面に直角なＹ方向とのＸＹ２方向に位置決めするためのＸ方向移動テーブル２６ａ、およびＹ方向移動テーブル２６ｂを持ち、それらをモータ３１、３２によって正逆駆動することにより回路基板１６を水平面上のどの位置にも位置決めできるようにしている。
【００３７】
しかし、部品実装ヘッド２３に設定される移動方向との関係により、例えば、部品実装ヘッド２３がＸＹ２方向の一方にだけ移動される場合を考えると、基板保持手段１７は水平面上の部品実装ヘッド２３が移動できない今１つの方向で回路基板１６を移動させて位置決めできれば、回路基板１６および部品実装ヘッド２３の相対移動によって、回路基板１６の上のどの位置にもＩＣチップ１２などの部品を実装することができると言うように、基板保持手段１７での回路基板１６などの基板の位置決め方向は自由に設定できる。前記接合材料１５の硬化操作を行うヒータ１８は回路基板１６を直接受載する本実施の形態ではＸ方向移動テーブル２６ａに設けてあり、回路基板１６を受載すると同時にこれを加熱するようにしてある。回路基板１６の加熱温度はセンサ４１によりモニタしてその温度情報を制御装置２４に入力し、制御装置２４はこの入力を基にヒータ１８への通電を制御し、回路基板１６を一定温度に保持できるようにする。しかし、加熱方法は種々の方法を採用することができる。
【００３８】
部品供給位置２０、接合材料供給位置２１、および接合位置２２は図１に示すＸ方向に一列に並ぶように設定されているので、部品実装ヘッド２３は少なくともこのＸ方向に往復移動できれば、吸着ノズル１３をそれらの位置に順次に移動させてＩＣチップ１２などを回路基板１６の所定位置に実装することはできる。
【００３９】
本実施の形態では部品実装ヘッド２３もＸＹ２方向に位置決めできるようにしてあり、モータ３４によるＸ方向テーブル３５の正逆駆動により部品実装ヘッド２３をＸ方向に移動させ、モータ３６によるＹ方向テーブル３７の正逆駆動により部品実装ヘッド２３をＹ方向に移動させる。これによって、部品供給位置２０に移動されたトレー２５にマトリックス状に配列して収納されたＩＣチップ１２などの部品をトレー２５の移動なしに吸着保持してピックアップすることができるし、ＸＹ２方向に回路基板１６を位置決めする基板保持手段１７との間で、回路基板１６の所定位置に実装する際に、どちらか有利になる側の移動を採用するとよいし、双方の移動を複合して行うこともできる。
【００４０】
また、部品実装ヘッド２３はモータ３８の正逆駆動により吸着ノズル１３を昇降させることができ、トレー２５によって供給されるＩＣチップ１２などの部品を吸着保持してピックアップし、これを接着剤槽１４内の接合材料１５の表面１５ａに近づけ、または接触させ、あるいは押し入れて後、ＩＣチップ１２を持ち上げて接合材料１５の表面１５ａから引き離して、接合材料１５の実装面１２ａへの前記のような供給を行い、接合材料１５を供給した後のＩＣチップ１２や、ピックアップしたままの他の電子部品などの各種の部品を、位置決めされた回路基板１６の上に上方から当てがってフリップチップ実装し、あるいは他の方式の実装を行うことを繰り返し行える。
【００４１】
しかし、部品実装ヘッド２３の移動方式や移動方向は必要に応じて自由に設定できるし、そのための部品実装ヘッド２３の移動、および位置決めの機構も種々なものを採用することができる。例えば、図１に示す部品実装ヘッド２３は３軸ロボットによって移動される構造となっているが、４軸以上のロボットによって移動されるようにすると、部品供給位置２０、接合材料供給位置２１、および接合位置２２のどのような配置にも対応できるようになるし、より短く、かつ、吸着ノズル１３による各種作業にもより無理のない、合理的な経路でＩＣチップ１２などの部品を取り扱えるようになる。
【００４２】
本実施の形態の図１に示す部品の実装装置はさらに、吸着ノズル１３または吸着ノズル１３が保持し、実装面１２ａに接合材料１５を供給すべきＩＣチップ１２と貯留された接合材料１５の表面１５ａとの間の距離を計測する計測手段４２と、この計測手段４２により計測された計測情報を基に吸着ノズル１３が保持しているＩＣチップ１２などの部品を接合材料１５に近づける位置を制御する制御手段４３とを備えている。
【００４３】
これにより、接着剤槽１４に貯留している接合材料１５の表面１５ａの位置を一定に保たなくても、ＩＣチップ１２の実装面１２ａを接合材料１５の表面１５ａに近づける作業の都度、接合材料１５の表面１５ａと吸着ノズル１３やＩＣチップ１２との間の距離に関し、計測手段４２による計測情報に基づき、制御手段４３がＩＣチップ１２の実装面１２ａを接合材料１５の表面１５ａに近づける位置を制御するので、ＩＣチップ１２の実装面１２ａへの接合材料１５の付着域および付着かさを設定通りに制御することができ、接合材料１５のＩＣチップ１２まわりへの拡がりを所定範囲内に規制しての、ＩＣチップ１２の確実なフリップチップ実装を安定して達成することができ、接合材料１５に揮発性があるなどして表面１５ａのレベルを一定に保てないか、保ち難い現状では特に有効である。
【００４４】
１つの実施例として制御手段４３は、制御装置２４の内部機能としてあるが、これに限られることはなく、制御装置２４とは別の外部装置とすることもできる。制御手段４３は計測手段４２からの、ＩＣチップ１２の実装面１２ａが接合材料１５の表面１５ａと所定位置まで近接し、あるいは接触し、あるいは表面１５ａに押し沈めれたかどうかを示す、吸着ノズル１３と表面１５ａとの間の位置、あるいは距離の情報であってもよいし、ＩＣチップ１２が表面に所定位置まで近づき、あるいは接触したことを計測手段４２と接合材料１５の表面１５ａとの間の距離情報を与えて判別させるものでもよい。これらには、光学的な反射を用いたいわゆる三角測距方式のものを採用することができるし、発進信号の表面１５ａからの反射の時間を採用したものでもよい。いずれにしても、表面１５ａとの非接触な方式によるのが好適である。非接触であると接合材料１５の付着による影響を受けない利点がある。
【００４５】
実施例について説明すると、ＩＣチップ１２の実装面１２ａを接合材料１５の表面１５ａに接触させた後、直ぐにＩＣチップ１２を引き上げて表面１５ａから引き離すことによって、実装面１２ａに接合材料１５を１ｍｍ間隔での高密度実装に十分対応できる状態に供給することができた。これを満足する接合材料１５の粘度は５〜２００Ｐａ・Ｓｅｃの範囲であり、ｃＰに換算すると５０〜２０００ｃＰと広範囲に適応できた。
【００４６】
従来の供給方法と、本発明の供給方法とで、同じ接合材料１５を供給したときの、ＩＣチップ１２の実装面１２ａサイズと、実装面１２ａの面積を１００としたときの実装後の接合材料１５の拡がり面積比との関係を比較したところ、図４に示すグラフのようになった。図４で△線は従来の供給方法を示し、○線は本発明の場合を示している。図４で分かるように、従来の供給方法に比し本発明の供給方法では全体に接合材料１５の拡がりを小さく抑えられている上、実装面１２ａのサイズ、つまりＩＣチップ１２のサイズが小さくなると、従来の供給方法ではＩＣチップ１２に対する接合材料１５の拡がり量が目立って大きくなるのに対し、本発明の供給方法では接合材料１５の拡がり量がほとんど大きくならない。
【００４７】
これは、本発明の供給方法がＩＣチップ１２の微小化、実装のさらなる高密度化に対応できることを示している。
【００４８】
なお、接合材料１５の粘度にもよるが、実装面１２ａにバンプ１２ｂがあるようなものでは、これが接合材料１５の表面１５ａ内に入り込むことで接合材料１５をＩＣチップ１２の側に幾分引き上げていけるような場合は、実装面１２ａが表面１５ａに接する位置まで必ずしも近づけられなくても接合材料１５は供給できたし、実装面１２ａを接合材料１５の表面１５ａよりも下に押し沈められても接合材料１５がＩＣチップ１２の側周面１２ｃにまわり込ませずに、実装面１２ａにだけ接合材料１５を供給することもできた。
【００４９】
【発明の効果】
本発明の部品の実装方法およびその装置によれば、実装面に供給した接合材料は実装面が上に向いても、下に向いていても、部品の側周面にまわり込みにくく、接合材料の供給かさの設定が十分な自由度で、かつ幅広い粘度域にて達成されて、実装面に金属バンプなどの電気接続突起がある場合でも、部品と基板とを当てがって接合する際に双方の間を接合材料で十分に埋め切って確実な接合およびそれによる電気接続を図りながら、接合材料が部品のまわりに拡がる量および大きさを所定範囲内に規制することができるので、各種の電子部品をフリップチップ実装して電子回路基板などを製造するときの高密度実装の要求に対応することができる。また、部品と基板との接合材料による接合に際し、接合材料を硬化させる硬化操作を行うことにより、部品を基板に当てがって電気接続させた状態に固定することができ、電気接続不良が接合のあと事後的に発生するのを防止できる。特に、接合材料の１つの硬化操作として、基板を、部品を当てがう前から加熱しておいて加熱源とすることで、接合材料が供給された部品を基板に当てがった時点から即時に接合材料の所定温度での加熱が開始されるので、加熱源の温度の立ち上がりのための時間が不要となり硬化操作が短時間に達成され、作業能率が向上する。
【００５１】
この場合、部品の実装面と貯留された接合材料の表面とを近づけていって接合材料を部品の実装面に付着させた後、双方を引き離して接合材料の供給を終えるようにすることで、接合材料の供給操作が簡単で容易かつ短時間に達成できる利点があるし、部品の実装面と接合材料表面との近づけ状態や接合材料の粘度によって接合材料の供給かさを十分な自由度で設定することができる。
【００５３】
本発明の部品実装装置は、部品を供給する部品供給部と、ペースト状の接合材料を貯留する貯留部と、基板を部品との接合位置に位置決め保持し接合作業に供する基板保持手段と、部品供給部で供給される部品を部品取り扱いツールにより保持して貯留部の接合材料上に持ち運んで、その表面に部品の実装面を近づけて行って接合材料を付着させた後双方を引き離し、その部品を基板保持手段により接合位置に位置決めされている基板の上に持ち運んでその所定位置に実装面を当てがい、部品と基板とを接合して電気接続することを繰り返し行う部品実装ヘッドと、部品取り扱いツールまたは部品取り扱いツールが保持している部品と貯留された接合材料の表面との間の距離を計測する計測手段と、この計測手段により計測された計測情報を基に取り扱いツールが保持している部品を接合材料に近づける位置を制御する制御手段とを備えたことを特徴としており、部品の供給をも含めて、一定のプログラムに従い自動的に確実に能率よく達成することができる。また、部品の実装面を接合材料の表面に近づける作業の都度、接合材料の表面と部品取り扱いツールや部品との間の距離の計測手段による計測情報に基づき、制御手段が部品の実装面を接合材料の表面に近づける位置を制御するようにすると、貯留している接合材料の表面位置を一定に保たなくても、部品の実装面への接合材料の付着域および付着かさを設定通りに制御することができ、接合材料の部品まわりへの拡がりを所定範囲内に規制しての確実な部品のフリップチップ実装を安定して達成することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る部品の実装方法およびそれを実現する部品の実装装置を示す側面図である。
【図２】図１に示す方法および装置で行ったＩＣチップの実装面に供給した接合材料の状態を示す側面図である。
【図３】図１に示す方法および装置で実装したＩＣチップの状態を示し、その（ａ）は平面図、その（ｂ）は回路基板とＩＣチップとの接合、電気接続の状態を示す断面図である。
【図４】従来の供給方法と本発明の供給方法との、接合材料の拡がりの違いを比較するグラフである。
【図５】従来のベアＩＣチップの実装方法を示す側面図である。
【図６】図５に示す方法で実装したＩＣチップの状態を示し、その（ａ）は平面図、その（ｂ）は回路基板とＩＣチップとの接合、電気接続の状態を示す断面図である。
【符号の説明】
１１部品供給部
１２ＩＣチップ
１２ａ実装面
１２ｂバンプ
１３吸着ノズル
１４接着剤槽
１５接合材料
１６回路基板
１６ａ電極パターン
１７基板保持手段
１８ヒータ
２０部品供給位置
２１接合材料供給位置
２２接合位置
２３部品実装ヘッド
２４制御装置
２４ａ記憶手段
４２計測手段
４３制御手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a component mounting method and apparatus, and more particularly, to a component mounting method and apparatus employing a flip chip mounting method in which a component and a substrate are bonded using a paste-like bonding material and both are electrically connected. It is about.
[0002]
[Prior art]
Conventionally, when flip-chip mounting a bare IC chip on a circuit board, a bonding material is supplied to the side of the board. For example, as shown in FIG. 5A, the bonding material d is supplied by a dispenser e or the like to the position where the bare IC chip c is mounted on the substrate b by using a dedicated coating apparatus a. The substrate b to which the bonding material d is applied is transferred to the component mounting apparatus f shown in FIG. 5C through various transport processes shown in FIG. In the component mounting apparatus f, the IC chip c supplied by the component supply unit is sucked and held by the suction nozzle j and carried on the substrate b positioned at the mounting position, and the mounting surface c1 of the IC chip c is joined to the substrate b. The IC chip c and the substrate b are bonded to each other at a predetermined position where the material d is supplied and bonded to each other by the bonding material d, so that both are electrically connected. Usually, the bonding material d is cured by heating or light irradiation. .
[0003]
The substrate b has an electrode pattern g as shown in FIG. 6B for electrical connection with the IC chip c, and metal bumps provided on the mounting surface c1 of the IC chip c by bonding via the bonding material d. Contact with h is achieved.
[0004]
By the way, a large number of IC chips c are usually flip-chip mounted on the substrate b. In the coating apparatus a, the bonding material d is supplied in advance to a large number of positions on the substrate b where the IC chips c are mounted. Become.
[0005]
However, the bonding material d before curing does not have a sufficient bonding force, and if the bonding material d is not cured while the IC chip c is pressed against the substrate b, the IC chip c is floated, resulting in poor electrical connection.
[0006]
Therefore, in the component mounting apparatus f, the IC chip c is sequentially flip-chip mounted together with the curing operation of the bonding material d as described above at a plurality of positions where the bonding material d of the substrate b is supplied. Consideration is given so that the bonding material d at the mounting position is not cured before the IC chip c is applied due to the influence of the ambient temperature or the curing operation at the position where the IC is mounted. .
[0007]
[Problems to be solved by the invention]
On the other hand, recently, there is an increasing demand for miniaturization of electronic components and higher mounting density. To cope with this, the conventional flip chip mounting method has a problem that the bonding material d spreads around the IC chip c as shown in FIGS. 6 (a) and 6 (b). When the bonding material d spreads around the IC chip c, if the mounting interval of the IC chips c is reduced to, for example, about 1 mm for high-density mounting, the mounting of the IC chip c shown in FIGS. In this case, the bonding material d spreading around the IC chip c is covered and hardened on the electrode pattern g at the mounting position of the IC chip c indicated by the adjacent virtual line. Therefore, when the next IC chip c is mounted at the adjacent position, the contact between the electrode pattern g and the metal bump h of the IC chip c is hindered, and the electrical connection becomes unstable or a connection failure is caused. The quality and yield will decrease.
[0008]
The bonding material d is supplied onto the substrate b by the dispenser e as shown in FIG. 5A. When the dispenser e is pulled away from the substrate b after the supply, the bonding material d supplied onto the substrate b is the first. 5A is raised as indicated by phantom lines, but then spreads around and low as shown in FIG. 5B due to the wettability with the substrate b and its own surface tension. Become.
[0009]
There is a certain relationship between the size of the bonding material d shown by the phantom line in FIG. 5A and the size of the bonding material d shown in FIG. 5B, and the size of the bonding material d after spreading. You can control it. However, if the bonding material d after spreading is too low, when the IC chip c is applied after the bonding material d of the substrate b is supplied, an electric current such as a metal bump h is applied to the mounting surface c1 of the IC chip c. In particular, when there is a protrusion to be connected and it is possible to float between the mounting surface c1 and the substrate b, the mounting surface c1 and the substrate b are not completely filled with the bonding material d, resulting in poor bonding, and electrical connection. In particular, when the solder bump that melts and solidifies is not used, poor electrical connection, inability, looseness or dropping of the IC chip c are likely to occur.
[0010]
In order to suppress the spread by increasing the viscosity of the bonding material d, the bonding material d is supplied to the substrate b with the dispenser e, and then the substrate b is soiled and made defective by stringing when the bonding material d is separated from the substrate b. This also has a limit in restricting the spread of the bonding material d and cannot be sufficiently suppressed.
[0011]
Therefore, in the prior art, when supplying the bonding material d onto the substrate b by the dispenser e, firstly, it is important to ensure the supply bulk of the bonding material d that can avoid the bonding failure. The spread of d is second only. As a result, the problem of spreading of the bonding material d around the IC chip c cannot be solved while suppressing the viscosity of the bonding material d to be used in a narrow range.
[0012]
The inventors conducted various experiments on a new method for supplying a bonding material. When the bonding material is supplied to the mounting surface of the component and bonded to the substrate, the bonding material spreads around the component. It was found that it can be suppressed.
[0013]
An object of the present invention is to provide a component mounting method and apparatus that can cope with higher density based on such new knowledge.
[0014]
[Means for Solving the Problems]
  In order to achieve the above object, the present inventionAccording to claim 1The component mounting method isFirst,Flip chip mounting is performed by joining the component and the board using a paste-like bonding material to perform mutual electrical connection, and the component and the board are joined by the bonding material supplied to the mounting surface side of the component. And flip-chip mountingHowever, a curing operation for curing the bonding material is performed when the component and the substrate are bonded with the bonding material, and the substrate is heated before the component is applied as one heating operation to be a heating source.It is characterized by that.
[0015]
  In this way, when the bonding material is supplied to the mounting surface side of the component, the supplied bonding material is unlikely to wrap around the side surface of the component even when the mounting surface is facing upward, and the bulk of the bonding material is sufficient. When the mounting surface is downward, the supplied bonding material is less likely to go around the side peripheral surface of the component, and a sufficient degree of freedom in setting the supply bulk of the bonding material can be achieved in a wide viscosity range. In this way, if the mounting surface of a component that is supplied with bonding material is applied to the board with the appropriate setting of the prevention of wrapping around the side surface of the component and the supply bulk, the component and the board are bonded to each other. Even if there are electrical connection protrusions such as, the amount and size of the bonding material spread around the part while fully bonding between the component and the board with the bonding material to ensure reliable bonding and electrical connection thereby It is possible to regulate within a predetermined range, and it is possible to meet the demand for high-density mounting when manufacturing various types of electronic components by flip-chip mounting to manufacture electronic circuit boards and the like.
  In addition, when performing a curing operation in which the bonding material is heated or / and cured by light when bonding the component and the substrate with the bonding material, the component can be fixed to the substrate and electrically connected to the substrate. It is possible to prevent an electrical connection failure from occurring after joining. As one curing operation, if the substrate is heated before being applied to a component and used as a heating source, the substrate is heated at a predetermined temperature from the time when the component supplied with the bonding material is applied to the substrate. Since heating is immediately started as a source, the time for rising the temperature of the heating source is not required, the curing operation is achieved in a short time, and the work efficiency is improved. Examples of the bonding material that can be employed include those that do not contain conductive particles and anisotropic conductive pastes in which conductive particles are uniformly dispersed. In the latter case, the bonding material itself is not electrically conductive by the conductive particles, but the conductive particles in the bonding material are interposed between the two electrical connections when the component is placed on the board to assist both electrical connections. Therefore, the electrical connectivity by joining the component and the substrate can be improved, and the product quality can be stabilized.
[0017]
  in this case,When the mounting surface of the component and the surface of the stored bonding material are brought close to each other and the bonding material is attached to the mounting surface of the component, then the both sides are separated to finish supplying the bonding material. It is easy and easy to achieve in a short time, and the supply volume of the bonding material can be set with sufficient flexibility depending on the closeness of the component mounting surface and the bonding material surface and the viscosity of the bonding material. The above method can be achieved more advantageously.
[0019]
  The mounting method on the board by handling a series of components as described above consists of a component supply unit that supplies the component, a storage unit that stores paste-like bonding material, and a substrate that is positioned and held at the bonding position of the component. The board holding means used for the joining work and the parts supplied by the parts supply part are held by the part handling tool and carried on the joining material of the storage part, and the part mounting surface is brought close to the surface to carry the joining material. The parts that are separated from each other after being attached, the parts are carried on the board positioned at the joining position by the board holding means, the mounting surface is applied to the predetermined position, and the parts and the board are joined repeatedly. Mounting head andThe measuring tool that measures the distance between the part handling tool or the part held by the part handling tool and the surface of the stored joint material, and the handling tool holds based on the measurement information measured by this measuring means. Control means for controlling the position at which the parts being moved approach the bonding material;With the component mounting apparatus having the above, it is possible to achieve automatically and surely and efficiently in accordance with a certain program including the supply of components.
[0020]
  Especially with this device,The measuring tool that measures the distance between the part handling tool or the part held by the part handling tool and the surface of the stored joint material, and the handling tool holds it based on the measurement information measured by this measuring means. Control means for controlling the position at which the parts being moved closer to the bonding material;ByEven if the surface position of the stored bonding material is not kept constant, the distance between the surface of the bonding material and the component handling tool or component is reduced each time the mounting surface of the component is brought close to the surface of the bonding material. Based on the information measured by the measuring means, the control means controls the position where the component mounting surface is brought close to the surface of the bonding material, so that the adhesion area and the adhesion depth of the bonding material to the component mounting surface can be controlled as set. In addition, it is possible to stably achieve the flip chip mounting of the component by restricting the spread of the bonding material around the component within a predetermined range.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a component mounting method and apparatus according to the present invention will be described below with reference to the drawings.
[0022]
As shown in FIG. 1, the component mounting method according to the present embodiment uses a paste-like bonding material 15 as a mounting target component for a chip-shaped electronic component, particularly an IC chip 12 such as a bare IC. This is an example in which the IC chip 12 is flip-mounted on a circuit board 16 as an example of the board to be mounted. Referring to the component mounting apparatus shown in FIG. 1, the IC chip 12 and the circuit board 16 are joined as shown in FIG. 1C and FIG. For chip mounting, as shown in FIGS. 1B and 1C ′, the IC chip 12 and the circuit board 16 are connected to each other by the bonding material 15 supplied to the mounting surface 12a side of the IC chip 12 in FIG. And the IC chip 12 and the circuit board 16 are electrically connected as shown in FIG. 3B to be flip-chip mounted.
[0023]
For such flip chip mounting, the mounting surface 12a of the IC chip 12 and the circuit board 16 are provided with electrical connection portions for connecting circuit patterns and the like carried by the IC chip 12 respectively. The electrical connection portion is usually an electrode pattern 16a as shown in FIG. 3B where the circuit board 16 side is a part of a circuit pattern or the like, and the IC chip 12 side is a bump 12b provided on an electrode portion such as a circuit pattern or the like. It is said. The bumps 12b include solder bumps that electrically connect the IC chip 12 and the circuit board 16 by melting and curing themselves, and metal bumps made of gold or the like that electrically connect the IC chip 12 and the circuit board 16 without melting. There is. The component mounting method of the present invention can be applied to any of them. However, the present invention is particularly effective in the case of metal bumps in which the spreading of the bonding material 15 around the parts is likely to be a problem, and only this case will be described below.
[0024]
As described above, when the bonding material 15 is supplied to the mounting surface 12a side of the IC chip 12, even if the mounting surface 12a is directed upward, the supplied bonding material 15 is affected by the surface tension and wettability of the IC chip 12 itself. It is difficult to wrap around the side peripheral surface 12c, and the supply bulk of the bonding material 15 can be set with a sufficient degree of freedom. In particular, when the mounting surface 12a is downward as shown in FIGS. Is more difficult to go around the side peripheral surface 12c of the IC chip 12 due to the action of gravity, and the bonding material 15 gathers at the center of the mounting surface 12a and hangs down at the full angle of repose. The setting can be achieved with a sufficient degree of freedom and in a wide viscosity range. Such a feature is the same in any case where the bonding material 15 is supplied manually or automatically by a dispenser or the like, and is almost the same regardless of the method of supplying the bonding material 15.
[0025]
In this way, the mounting surface 12a of the IC chip 12 to which the bonding material 15 is supplied is shown in FIG. 1 (c) with the setting of the supply volume and the prevention of the bonding material 15 from entering the side peripheral surface 12c of the IC chip 12. When the IC chip 12 and the circuit board 16 are bonded to the circuit board 16 as shown in the figure, even if there are protrusions for electrical connection such as bumps 12b on the mounting surface 12a, the IC chip 12 and the circuit board 16 As shown in FIG. 3B, the amount and size of the bonding material 15 spreading around the IC chip 12 are shown while being sufficiently filled with the bonding material 15 to achieve reliable bonding and electrical connection thereby. 3 (a) and (b) can be regulated within a predetermined range.
[0026]
Accordingly, the bonding material 15 used for flip chip mounting of the IC chip 12 indicated by a solid line in FIG. 3B should be electrically connected by flip chip mounting of another IC chip 12 indicated by a virtual line to be densely mounted. Even if the bonding material 15 used for flip chip mounting of the solid line IC chip 12 does not cover the electrode pattern 16a and is cured before the flip chip mounting of the adjacent IC chip 12 of the virtual line, the adjacent IC chip 12 It does not interfere with flip chip mounting. Therefore, it is possible to meet the demand for high-density mounting when manufacturing various types of electronic components by flip-chip mounting to manufacture an electronic circuit board or the like.
[0027]
When bonding the IC chip 12 and the circuit board 16 with the bonding material 15, the bonding material 15 is usually cured, which is performed by a heating or / and light curing operation, and the IC chip 12 is applied to the circuit board 16. Thus, it is possible to fix the state of being joined and electrically connected, and it is possible to prevent an electrical connection failure from occurring afterwards. As one curing operation, in the present embodiment, the circuit board 16 is heated by the heater 18 or the like before the IC chip 12 is applied, and is used as a heating source. As a result, the IC substrate 12 supplied with the bonding material 15 as shown in FIG. 1C ′ is applied to the circuit substrate 16 as shown in FIG. Becomes a heating source of a predetermined temperature, and heating is immediately started. Therefore, a time for rising the temperature of the heating source is not required, the curing operation is achieved in a short time, and the work efficiency is improved.
[0028]
As the paste-like bonding material, generally an ultraviolet curable first-curing material combined with heating is used. Some of them have a liquid epoxy acrylate resin as a main component. The viscosity can be freely set according to the addition ratio of the thickener. However, as long as the method of the present invention can be achieved, any other adhesives and bonding materials that are already known and newly provided can be used.
[0029]
The bonding material 15 further includes a material that does not contain conductive particles and an anisotropic conductive paste in which the conductive particles are uniformly dispersed, and any of them can be used. However, in the latter case, the bonding material 15 itself is not conductive by the conductive particles, but both electrical connection portions when the IC chip 12 is applied to the circuit board 16 as shown in FIG. 3B, conductive particles (not shown) in the bonding material 15 intervene between the bumps 12b and the electrode patterns 16a shown in FIG. 3B to assist the electrical connection between them, so that the IC chip 12 and the circuit board 16 are bonded. Can improve the electrical connectivity, and can stabilize the quality of products such as electronic circuit boards manufactured by mounting electronic components such as the IC chip 12.
[0030]
In the component mounting method of the present embodiment, in particular, the mounting surface 12a of the IC chip 12 and the surface 15a of the bonding material 15 stored in the adhesive tank 14 are shown in FIG. (B), the bonding material 15 is attached to the mounting surface 12a of the IC chip 12, and then both are separated to finish supplying the bonding material 15 to the mounting surface 12a. Thus, the operation of supplying the bonding material 15 is simple and easy and can be achieved in a short time, and the bonding material 15 depends on the closeness of the mounting surface 12a of the IC chip 12 and the bonding material surface 15a and the viscosity of the bonding material 15. Can be set with a sufficient degree of freedom, and the component mounting method described above can be achieved more advantageously.
[0031]
Moreover, in order to employ such a component mounting method, in this embodiment, as shown in FIG. 1, the IC chip 12 of the component supply unit 11 is sucked by a suction nozzle 13 as an example of a component handling tool. It is held and carried on the stored bonding material 15, the mounting surface 12 a of the IC chip 12 is brought close to and the bonding material 15 is attached, and then both are separated to attach the bonding material 15 to the mounting surface 12 a of the IC chip 12. Subsequently, the IC chip 12 with the bonding material 15 attached is carried on the circuit board 16 and the mounting surface 12a is applied to a predetermined position of the circuit board 16 to bond the IC chip 12 and the circuit board 16 to each other. Connect and flip chip.
[0032]
Thus, by a series of handling while the IC chip 12 is held by the suction nozzle 13 which is a component handling tool, the bonding material 15 is supplied to the mounting surface 12a of the IC chip 12, and the IC by the supplied bonding material 15 is provided. The bonding between the chip 12 and the circuit board 16 and the electrical connection thereby can be achieved, and the entire mounting operation is simplified and is easily achieved in a short time.
[0033]
In order to realize a method of handling various components such as the IC chip 12 in series and mounting them on a substrate such as the circuit board 16 as described above, the component mounting apparatus shown in FIG. A component supply unit 11 that supplies components to the component supply position 20, an adhesive tank 14 as an example of a storage unit that stores paste-like bonding material 15 in the bonding material supply position 21, and an IC chip 12 are held and various types are held. In addition to the suction nozzle 13 as an example of a component handling tool, the circuit board 16 is positioned and held at the joining position 22 shown in FIG. The IC chip 12 supplied from the component supply unit 11 at the component supply position 20 is held by the suction nozzle 13, moved to the bonding material supply position 21, and stored in the adhesive tank 14. After the IC chip 12 is carried on the adhesive tank 14, the mounting surface 12 a of the IC chip 12 is brought close to the surface 15 a to attach the bonding material 15, the both are separated, and the bonding material 15 is attached. The IC chip 12 is carried on the circuit board 16 positioned at the joining position 22, the mounting surface 12 a is applied to the predetermined position, and the IC chip 12 and the circuit board 16 are joined to make electrical connection. The component mounting head 23 is repeatedly operated, and each of these means is operated by a control device 24 using a microcomputer or other electric circuit in accordance with a predetermined program stored in various internal or external storage means 24a. As described above, the IC chips 12 are handled in series by the suction nozzle 13 and mounted on the circuit board 16 as described above. Law, including the supply of parts such as IC chip 12, you are possible to achieve good automatically ensures efficiency.
[0034]
The component supply unit 11 is housed in, for example, a tray 25 in order to supply various types of IC chips 12 to be flip-chip mounted or electronic components mounted in combination with other methods in order to supply what is needed each time. Handle parts. The tray 25 storing necessary components is moved to the component supply position 20 by normal rotation driving by the motor 28 of the tray conveying means 27, and the components such as the IC chip 12 stored in the tray 25 are used for mounting. If the IC chip 12 or the like to be supplied next is different, the tray 25 at the component supply position 20 is returned to the base by the reverse drive of the motor 28 of the tray conveying means 27, and then the necessary IC is stored. The tray 25 containing the chips 12 and the like is moved to the component supply position 20 to supply the components repeatedly. However, in order to supply various components such as the IC chip 12, various known methods corresponding to the types of the components can be adopted.
[0035]
The part handling tool is not limited to the suction nozzle 13, and various types according to the type of part to be handled can be adopted, such as a chuck type that sandwiches the part and a connection type that is connected to the part. Can be used by selecting multiple types of the same type or combining multiple types of different types.
[0036]
In response to this, the board holding means 17 carries the circuit board 16 by the normal rotation drive of the motor 33 and uses it for mounting the IC chip 12 and the like. It is used in combination with a conveying means 29 that is carried out by driving. The substrate holding means 17 has an X-direction moving table 26a and a Y-direction moving table 26b for positioning the circuit board 16 carried in, for example, the XY2 direction of the X direction in the drawing and the Y direction perpendicular to the paper surface. The circuit board 16 can be positioned at any position on the horizontal plane by driving the motors 31 and 32 forward and backward.
[0037]
However, considering the case where the component mounting head 23 is moved only in one of the XY2 directions due to the relationship with the movement direction set for the component mounting head 23, the board holding means 17 can be used for the component mounting head 23 on a horizontal plane. If the circuit board 16 can be moved and positioned in one direction that cannot move, the component such as the IC chip 12 is mounted on any position on the circuit board 16 by relative movement of the circuit board 16 and the component mounting head 23. As can be said, the positioning direction of the board such as the circuit board 16 in the board holding means 17 can be freely set. In the present embodiment in which the circuit board 16 is directly received, the heater 18 that performs the curing operation of the bonding material 15 is provided on the X-direction moving table 26a, and the circuit board 16 is received and heated at the same time. is there. The heating temperature of the circuit board 16 is monitored by the sensor 41, and the temperature information is input to the control device 24. The control device 24 controls energization to the heater 18 based on this input, and keeps the circuit board 16 at a constant temperature. It can be so. However, various heating methods can be employed.
[0038]
Since the component supply position 20, the bonding material supply position 21, and the bonding position 22 are set so as to be aligned in a row in the X direction shown in FIG. 1, if the component mounting head 23 can reciprocate at least in this X direction, the suction nozzle The IC chip 12 and the like can be mounted at predetermined positions on the circuit board 16 by sequentially moving 13 to those positions.
[0039]
In the present embodiment, the component mounting head 23 can also be positioned in the XY2 direction. The component mounting head 23 is moved in the X direction by forward / reverse driving of the X direction table 35 by the motor 34, and the Y direction table 37 by the motor 36. The component mounting head 23 is moved in the Y direction by forward / reverse driving. As a result, components such as the IC chip 12 arranged and stored in the matrix 25 in the tray 25 moved to the component supply position 20 can be picked up and picked up without moving the tray 25, and in the XY2 direction. When mounting the circuit board 16 at a predetermined position on the circuit board 16 with the board holding means 17 for positioning the circuit board 16, it is advisable to adopt the movement on which side is advantageous, or to perform both movements in combination. You can also.
[0040]
Further, the component mounting head 23 can raise and lower the suction nozzle 13 by forward / reverse driving of the motor 38, and suck and hold components such as the IC chip 12 supplied by the tray 25 to pick them up. After approaching, contacting, or pushing in the surface 15a of the bonding material 15 inside, the IC chip 12 is lifted and pulled away from the surface 15a of the bonding material 15 to supply the bonding material 15 to the mounting surface 12a as described above. Various components such as the IC chip 12 after supplying the bonding material 15 and other electronic components that have been picked up are applied onto the positioned circuit board 16 from above and flip-chip mounted. Alternatively, it is possible to repeatedly implement other methods.
[0041]
However, the moving method and moving direction of the component mounting head 23 can be freely set as necessary, and various moving and positioning mechanisms for the component mounting head 23 can be employed. For example, the component mounting head 23 shown in FIG. 1 has a structure that is moved by a three-axis robot. However, when the component mounting head 23 is moved by a four-axis or more robot, the component supply position 20, the bonding material supply position 21, and It is possible to deal with any arrangement of the joining position 22, and it is possible to handle components such as the IC chip 12 through a rational route that is shorter and more comfortable for various operations by the suction nozzle 13. Become.
[0042]
The component mounting apparatus shown in FIG. 1 of the present embodiment is further held by the suction nozzle 13 or the suction nozzle 13 and the IC chip 12 to be supplied with the bonding material 15 to the mounting surface 12a and the surface of the stored bonding material 15 Based on the measurement information measured by the measurement means 42 and the measurement information measured by the measurement means 42, the position of the component such as the IC chip 12 held by the suction nozzle 13 is controlled close to the bonding material 15. And a control means 43 for controlling.
[0043]
Thus, the bonding surface 12a of the IC chip 12 is brought into close contact with the surface 15a of the bonding material 15 every time the operation is performed so that the surface 15a of the bonding material 15 stored in the adhesive tank 14 is not kept constant. The position at which the control means 43 brings the mounting surface 12a of the IC chip 12 closer to the surface 15a of the bonding material 15 based on the measurement information by the measurement means 42 with respect to the distance between the surface 15a of the material 15 and the suction nozzle 13 or the IC chip 12. Therefore, it is possible to control the adhesion area and the adhesion mass of the bonding material 15 to the mounting surface 12a of the IC chip 12 as set, and the spread of the bonding material 15 around the IC chip 12 is regulated within a predetermined range. Thus, reliable flip-chip mounting of the IC chip 12 can be stably achieved, and the level of the surface 15a can be reduced because the bonding material 15 is volatile. Do not be kept constant, it is particularly effective in hard to maintain status quo.
[0044]
In one embodiment, the control means 43 is an internal function of the control device 24, but is not limited to this, and may be an external device different from the control device 24. The control means 43 indicates whether the mounting surface 12a of the IC chip 12 from the measuring means 42 is close to or in contact with the surface 15a of the bonding material 15 or whether it is depressed or depressed on the surface 15a. Between the measuring means 42 and the surface 15a of the bonding material 15 that the IC chip 12 has approached or contacted the surface up to a predetermined position. It may be determined by giving distance information. For these, a so-called triangulation system using optical reflection can be employed, or a time of reflection of the start signal from the surface 15a can be employed. In any case, it is preferable to use a non-contact method with the surface 15a. If it is non-contact, there is an advantage that it is not affected by adhesion of the bonding material 15.
[0045]
An embodiment will be described. After the mounting surface 12a of the IC chip 12 is brought into contact with the surface 15a of the bonding material 15, the IC chip 12 is immediately pulled up and pulled away from the surface 15a. We were able to supply it in a state that can sufficiently cope with high-density mounting in Japan. The viscosity of the bonding material 15 satisfying this was in the range of 5 to 200 Pa · Sec, and could be applied in a wide range of 50 to 2000 cP when converted to cP.
[0046]
The bonding material after mounting when the mounting surface 12a size of the IC chip 12 and the area of the mounting surface 12a are set to 100 when the same bonding material 15 is supplied by the conventional supply method and the supply method of the present invention. When the relationship with the area ratio of 15 spread was compared, it became like the graph shown in FIG. In FIG. 4, the △ line indicates a conventional supply method, and the ◯ line indicates the case of the present invention. As can be seen from FIG. 4, in the supply method of the present invention, the spread of the bonding material 15 is suppressed as a whole compared to the conventional supply method, and when the size of the mounting surface 12a, that is, the size of the IC chip 12 is reduced. In the conventional supply method, the spread amount of the bonding material 15 with respect to the IC chip 12 is remarkably increased, whereas in the supply method of the present invention, the spread amount of the bonding material 15 is hardly increased.
[0047]
This indicates that the supply method of the present invention can cope with the miniaturization of the IC chip 12 and further increase in the mounting density.
[0048]
Note that, depending on the viscosity of the bonding material 15, if the mounting surface 12 a has bumps 12 b, the bonding material 15 is somewhat lifted toward the IC chip 12 by entering the surface 15 a of the bonding material 15. In such a case, the bonding material 15 can be supplied even if the mounting surface 12a is not necessarily brought close to the position in contact with the surface 15a, and the mounting surface 12a is pushed down below the surface 15a of the bonding material 15. In addition, the bonding material 15 could be supplied only to the mounting surface 12 a without the bonding material 15 going around the side peripheral surface 12 c of the IC chip 12.
[0049]
【The invention's effect】
  According to the component mounting method and apparatus therefor according to the present invention, the bonding material supplied to the mounting surface is less likely to wrap around the side peripheral surface of the component, regardless of whether the mounting surface faces upward or downward. Even when there are electrical connection protrusions such as metal bumps on the mounting surface, the setting of the supply bulk is achieved with a sufficient degree of freedom and in a wide viscosity range. The amount and size of the bonding material spreading around the part can be regulated within a predetermined range while the gap between the two is sufficiently filled with the bonding material to ensure reliable bonding and electrical connection thereby. It is possible to meet the demand for high-density mounting when manufacturing electronic circuit boards and the like by flip-chip mounting electronic components.In addition, when bonding the component and the substrate with the bonding material, by performing a curing operation to cure the bonding material, it is possible to fix the component in a state of being electrically connected by being applied to the substrate, and the poor electrical connection is bonded. Can be prevented after the fact. In particular, as one curing operation of the bonding material, the substrate is heated before being applied to the component and used as a heating source, so that the component supplied with the bonding material is immediately applied from the point of application to the substrate. In addition, since the heating of the bonding material is started at a predetermined temperature, a time for rising the temperature of the heating source is not required, and the curing operation is achieved in a short time, thereby improving the work efficiency.
[0051]
  in this case,After bringing the mounting surface of the component close to the surface of the stored bonding material and attaching the bonding material to the mounting surface of the component, the both sides are separated to finish supplying the bonding material. The supply operation is simple and easy and can be achieved in a short time. The supply volume of the bonding material can be set with a sufficient degree of freedom depending on the closeness of the component mounting surface and the bonding material surface and the viscosity of the bonding material. it can.
[0053]
  A component mounting apparatus according to the present invention includes a component supply unit that supplies components, a storage unit that stores paste-like bonding material, a substrate holding unit that positions and holds a substrate at a bonding position with the component, and is used for bonding work, and a component The parts supplied by the supply part are held by the parts handling tool and carried on the joining material of the storage part, the parts mounting surface is brought close to the surface to attach the joining material, and then both parts are pulled apart. A component mounting head that repeatedly carries the substrate on the substrate positioned at the bonding position by the substrate holding means, applies the mounting surface to the predetermined position, and joins and electrically connects the component and the substrate.The measuring tool that measures the distance between the part handling tool or the part held by the part handling tool and the surface of the stored joint material, and the handling tool holds based on the measurement information measured by this measuring means. Control means for controlling the position at which the parts being moved approach the bonding material;It can be achieved automatically and reliably according to a certain program including the supply of parts.In addition, each time the work is performed to bring the component mounting surface closer to the surface of the bonding material, the control unit bonds the component mounting surface based on measurement information obtained by measuring the distance between the surface of the bonding material and the component handling tool or component. By controlling the position close to the surface of the material, it is possible to control the bonding area and the adhesion depth of the bonding material on the mounting surface of the component as set, even if the surface position of the stored bonding material is not kept constant. Therefore, it is possible to stably achieve the flip chip mounting of the component by restricting the spread of the bonding material around the component within a predetermined range.
[Brief description of the drawings]
FIG. 1 is a side view showing a component mounting method and a component mounting apparatus for realizing the component mounting method according to an embodiment of the present invention.
FIG. 2 is a side view showing a state of a bonding material supplied to a mounting surface of an IC chip performed by the method and apparatus shown in FIG.
3 shows a state of an IC chip mounted by the method and apparatus shown in FIG. 1, in which (a) is a plan view, and (b) is a cross section showing a state of bonding and electrical connection between a circuit board and the IC chip. FIG.
FIG. 4 is a graph comparing the difference in bonding material spread between the conventional supply method and the supply method of the present invention.
FIG. 5 is a side view showing a conventional bare IC chip mounting method.
6 shows the state of the IC chip mounted by the method shown in FIG. 5, in which (a) is a plan view, and (b) is a cross-sectional view showing the state of bonding and electrical connection between the circuit board and the IC chip. is there.
[Explanation of symbols]
11 Parts supply section
12 IC chip
12a Mounting surface
12b Bump
13 Suction nozzle
14 Adhesive tank
15 Bonding material
16 Circuit board
16a electrode pattern
17 Substrate holding means
18 Heater
20 Parts supply position
21 Bonding material supply position
22 Joining position
23 Component mounting head
24 Control device
24a storage means
42 Measuring means
43 Control means

Claims

In the component mounting method of flip chip mounting by joining the component and the substrate using a paste-like bonding material and making electrical connection to each other,
The bonding material supplied to the mounting surface side of the component is used to bond the component and the board, electrically connect the component and the board, and perform flip chip mounting. The bonding material is cured at the time of bonding with the bonding material between the component and the board. A component mounting method, wherein a curing operation is performed, and the substrate is heated as a heating source before applying the component as one curing operation .

In the component mounting method of flip chip mounting by joining the component and the substrate using a paste-like bonding material and making electrical connection to each other,
The bonding material was fed to the mounting surface of the component, though by joining a component and a substrate for flip-chip mounting make electrical connection of the component and the substrate, supplying a bonding material in a downward mounting surface of the component, and the component Mounting of a component characterized by performing a curing operation for curing the bonding material when bonding to the substrate with a bonding material, and heating the substrate before applying the component as a curing operation as one curing operation. Method.

In the component mounting method of flip chip mounting by joining the component and the substrate using a paste-like bonding material and making electrical connection to each other,
The bonding material was fed to the mounting surface of the component, the component and to then bond the substrate is flip-chip mounted perform electrical connection of the component and the substrate, part of the downward mounting surface and the reservoir surface of the bonding material After attaching the bonding material to the mounting surface of the component, the both sides are separated to finish supplying the bonding material, and a curing operation is performed to cure the bonding material when bonding the component and the substrate with the bonding material. A component mounting method characterized in that, as one curing operation, the substrate is heated before the component is applied and used as a heating source .

A component supply unit that supplies components, a storage unit that stores paste-like bonding material, a substrate holding unit that positions and holds the substrate at a bonding position with the component, and a bonding operation, and a component that is supplied by the component supply unit Is held by the component handling tool and carried on the bonding material of the storage part, the mounting surface of the component is brought close to the surface from the upper side to attach the bonding material, and then both are separated, and the component is separated by the substrate holding means A component mounting head that repeatedly carries the substrate on the board that is positioned and held at the bonding position, places the mounting surface at that position, and repeats the bonding of the component and the board, and the component handling tool or component handling tool. The measuring tool that measures the distance between the parts being stored and the surface of the stored bonding material, and the handling tool based on the measurement information measured by this measuring means Mounting apparatus components, characterized in that a control means for controlling the position closer parts that lifting the bonding material.

A component supply unit that supplies components, a storage unit that stores paste-like bonding material, a substrate holding unit that positions and holds the substrate at a bonding position with the component, and a bonding operation, and a component that is supplied by the component supply unit Is held by the component handling tool and carried on the bonding material of the storage part, the mounting surface of the component is brought close to the surface from the upper side to attach the bonding material, and then both are separated, and the component is separated by the substrate holding means A component mounting head that repeatedly carries the substrate on the board that is positioned and held at the bonding position, places the mounting surface at that position, and repeats the bonding of the component and the board, and the component handling tool or component handling tool. The measuring tool that measures the distance between the parts being stored and the surface of the stored bonding material, and the handling tool based on the measurement information measured by this measuring means And control means for controlling the position closer parts that lifting the bonding material, components and mounting apparatus of the parts comprising the curing means for curing the bonding material joined by light and / or heat and the substrate .

A component supply unit that supplies components, a storage unit that stores paste-like bonding material, a substrate holding unit that positions and holds the substrate at a bonding position with the component, and a bonding operation, and a component that is supplied by the component supply unit Is held by the component handling tool and carried on the bonding material of the storage part, the mounting surface of the component is brought close to the surface from the upper side to attach the bonding material, and then both are separated, and the component is separated by the substrate holding means A component mounting head that repeatedly carries the substrate on the board that is positioned and held at the bonding position, places the mounting surface at that position, and repeats the bonding of the component and the board, and the component handling tool or component handling tool. measuring means for measuring the distance between the Tei Ru component a reservoir surface of the bonding material, handling tools based on measurement information measured by the measuring means And control means for controlling the position closer parts that lifting the bonding material comprises a curing means for curing the bonding material bonding the components to a substrate by light and / or heat, the curing means being positioned in the mounting position A component mounting apparatus comprising at least heating means for heating a substrate .