JP2004339579A

JP2004339579A - Electrolytic treatment device and method

Info

Publication number: JP2004339579A
Application number: JP2003138521A
Authority: JP
Inventors: Koji Mishima; 浩二三島; Keisuke Namiki; 計介並木; Masao Houdai; 昌夫蓬臺; Junji Kunisawa; 淳次國澤; Natsuki Makino; 夏木牧野; Yukio Fukunaga; 由紀夫福永
Original assignee: Ebara Corp
Current assignee: Ebara Corp
Priority date: 2003-05-16
Filing date: 2003-05-16
Publication date: 2004-12-02
Also published as: US20050155865A1

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrolitic treatment device capable of producing products with various specifications in a state of the highest productivity while considering the quantity of the production, reducing production cost, and being applied even to the miniaturization of wirings flexibly. <P>SOLUTION: The electrolytic treatment device is equipped with: an electrolytic treatment unit 30 provided with a substrate holding part 40 of holding a substrate; and a counter plate 50 arranged at a position confronted with the substrate held by the substrate holding part 40; an elecyrolytic treatment unit 30 in which power is fed to the space between the substrate held by the substrate holding part 40 and the counter plate while an electrolytic solution is filled therein, and electrolytic treatment is performed; and a plurality of electrolytic solution feeding equipments 32a and 32b of feeding different kinds of electrolytic solutions. The electrolytic treatment unit 30 is constituted so as to alternatively be connected to one of the electrolytic solution feeding equipments 32a and 32b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、電解処理装置及び方法に係り、特に微細配線パターン（窪み）が形成された基板の表面に、銅等の配線材料をめっきにより成膜したり、基板の表面に形成した金属膜を電解エッチングにより除去したりするのに使用される電解処理装置及び方法に関する。
【０００２】
【従来の技術】
近年、半導体基板上に電気配線を形成するための配線材料として、アルミニウムまたはアルミニウム合金に代えて、電気抵抗率が低くエレクトロマイグレーション耐性が高い銅（Ｃｕ）を用いる動きが顕著になっている。銅はアルミニウムのような異方性エッチングによる配線形状の形成が一般に困難であるため、この種の銅配線は、基板の表面に設けた微細凹部の内部に銅を埋込む、いわゆる銅ダマシン技術によって一般に形成される。この銅配線を形成する方法としては、ＣＶＤ、スパッタリング及びめっきといった手法があるが、いずれにしても、基板のほぼ全表面に銅を成膜し、化学的機械的研磨（ＣＭＰ）や電解エッチングにより不要の銅を除去するようにしている。
【０００３】
図４は、この種の銅配線基板Ｗの製造例を工程順に示すもので、先ず、図４（ａ）に示すように、半導体素子を形成した半導体基材１上の導電層１ａの上にＳｉＯ_２からなる酸化膜２を堆積し、リソグラフィ・エッチング技術により微孔（ビアホール）３や配線溝（トレンチ）４等の配線用の微細凹部を形成し、その上にＴａＮ等からなるバリア層５、更にその上に電解めっきの給電層としてシード層７を形成する。
【０００４】
そして、図４（ｂ）に示すように、基板Ｗの表面に銅めっきを施すことで、半導体基材１の微孔３及び配線溝４内に銅を充填するとともに、酸化膜２上に銅膜６を堆積する。その後、化学的機械的研磨（ＣＭＰ）や電解エッチングにより、酸化膜２上の銅膜６及びバリア層５を除去して、微孔３及び配線溝４に充填させた銅膜６の表面と酸化膜２の表面とをほぼ同一平面にする。これにより、図４（ｃ）に示すように銅膜６からなる配線が形成される。
このように、配線材料がアルミニウムから銅に変わるにつれて、銅材料のめっきを行う電解めっき装置や、銅膜の電解エッチングを行う電解エッチング装置がにわかに注目を集めている。
【０００５】
図５に銅配線の製造に使用される従来の一般的な電解めっき装置を示す。この電解めっき装置は、例えばスミフボックス等の内部に多数の半導体ウエハ等の基板を収納した搬送ボックス１０を着脱自在な矩形状のハウジング１２を備えている。このハウジング１２の内部には、置台１４と、４台の電解めっきユニット１６と、２台の後洗浄ユニット１８が収納され、更に搬送ボックス１０及び置台１４との間で基板を搬送する搬送装置としての第１搬送ロボット２０と、置台１４、電解めっきユニット１６及び後洗浄ユニット１８との間で基板を搬送する搬送装置としての第２搬送ロボット２２が備えられている。
【０００６】
そして、４台の電解めっきユニット１６に共通の単一のめっき液供給設備２４が備えられ、このめっき液供給設備２４から各電解めっきユニット１６に共通のめっき液が個別に供給され回収されるようになっている。
【０００７】
これによって、基板を収納した搬送ボックス１０から１枚の基板が第１搬送ロボット２０により取出され、置台１４上に載置される。そして、この置台１４に載置された基板は、第２搬送ロボット２２によって、いずれかの電解めっきユニット１６に搬送され、この電解めっきユニット１６で銅めっき等の電解めっきが行われる。このめっき後の基板は、第２搬送ロボット２２によって、いずれかの後洗浄ユニット１８に搬送され、この後洗浄ユニット１８で基板の後洗浄及び後洗浄後のスピン乾燥が行われる。そして、このスピン乾燥後の基板は、第２搬送ロボット２２によって、置台１４に搬送されて載置され、この置台１４上に載置された基板は、第１搬送ロボット２０によって、搬送ボックス１０内の元の位置に戻される。
【０００８】
現在の銅配線等における配線の線幅は、一般に０．１５〜１００μｍの範囲にあり、電解めっき装置で使用されるめっき液は、硫酸銅、硫酸、塩酸、サプレッサー、アクセラレーター及びレベラで構成されるのが一般的である。また、１つの電解めっき装置で使用されるめっき液は、通常、一種類である。
【０００９】
一方、ピロりん酸銅めっき液のような高分極液を使用した電解めっきや無電解めっきで一次めっきを行って、シード層７（図４（ａ）参照）を補強乃至補修して完全なものとなし、しかる後、硫酸銅めっき液を使用した二次めっきを行って銅配線の埋込みを行うようにすることが提案されている。また、埋込み特性の異なる複数種の硫酸銅めっき液を一つの電解めっき装置に供給して、多段めっきを行うことも知られている。
【００１０】
このような多段めっきを行う電解めっき装置の従来例を図６に示す。この例は、２段めっきを行うようにしたものであり、例えばピロりん酸銅めっき液等の第１めっき液を供給する第１めっき液供給設備２４ａと、例えば硫酸銅めっき液等の第２めっき液を供給する第２めっき液供給設備２４ｂが備えられ、一方、電解めっきユニット１６も、第１めっき液供給設備２４ａに接続されて、第１めっき液を使用しためっきを行う第１電解めっきユニット１６ａと、第２めっき液供給設備２４ｂに接続されて、第２めっき液を使用しためっきを行う第２電解めっきユニット１６ｂに区分されている。更に、洗浄ユニットとして、後洗浄ユニット１８と中間洗浄ユニット２６が備えられている。
【００１１】
これにより、前述と同様にして置台１４に載置された基板は、いずれかの第１電解めっきユニット１６ａに搬送され、ここで第１めっき液を使用した一次めっきが施された後、第２搬送ロボット２２で中間洗浄ユニット２６に搬送され、ここで中間洗浄が行われる。そして、この中間洗浄後の基板は、第２搬送ロボット２２でいずれかの第２電解めっきユニット１６ｂに搬送され、ここで第２めっき液を使用した二次めっきが施され、しかる後、前述と同様に、後洗浄及びスピン乾燥後、搬送ボックス１０内に戻される。
【００１２】
このように、めっき液が異なる毎に異なる電解めっきユニットを使用して、単一の電解めっきユニットで２種類以上のめっき液を使用しためっきを行わないのは、微量の添加剤が混合してめっき特性が不安定になることを防止するためである。
【００１３】
【発明が解決しようとする課題】
例えば、ＬＳＩ分野では、既に０．１５μｍ以下の超微細な配線形成技術の開発が進んでいる。この場合、電解めっき法の埋込み特性に対して、更なる微細化対応、高アスペクト化対応が求められており、めっき液の開発も困難な技術的課題に直面しつつある。
【００１４】
しかし、超微細配線技術は、主に多層配線の下層部であるローカル配線に使用される技術であり、必ずしも線幅が１０〜１００μｍ程度の低アスペクトなグローバル配線を形成する技術としては、コスト的、技術的に最適ではない可能性が高い。これは、グローバル配線に求められめっき特性は、めっき上面の平坦な仕上がり、いわゆるレベリング性であるが、これに対して、ローカル配線に求められるめっき特性は、ボイドレスで微細凹部に銅を埋込むこと、すなわち高アスペクト比を有する微細凹部内への配線材料の埋込み性であるためである。そして、これらの異なる要求を同時に満足できるめっき液は未だ開発されていないのが現状である。
【００１５】
また、例えば銅配線を必要とする半導体デバイスは、多品種で少量ロットの生産を求められることが多く、更に半導体デバイスによって、配線幅、積層レイヤー数、それらの構成比率等は、一般に一定ではない。このため、従来の電解めっき装置のように、一種類のめっき液で全てのレイヤーの配線を形成したり、多様なデバイスを効率的に生産したりすることは困難である。また、複数種のめっき液を使用可能な装置構成を採用したとしても、めっき液毎に異なる電解めっきユニットを特定するような運用方法では、柔軟性に欠ける運用しかできず、しかも生産コストの増加に繋がってしまう。
【００１６】
以上、銅めっきを行う電解めっき装置における場合について説明したが、めっきと逆のプロセスを行う電解エッチング装置においても上記事情は同様である。すなわち、電解エッチングの特性も、電解めっき装置におけるめっき液と同様に、添加剤や電解質により調整することが可能であるが、多層配線の上層と下層で求められるプロセス要求は一様ではない。また、面内均一性、エッチングレートに対する要求は様々であり、これらの要求は、配線幅のみならず、配線疎密度、断面形状などによりに益々多様である。このため、異なる電解エッチング液を柔軟に運用できる装置の開発が求められていた。
【００１７】
本発明は上記事情に鑑みて為されたもので、多様な仕様の製品に対して、その生産量を加味しながら最も生産性の高い状態での生産が可能で、生産コストの削減を図ることができ、しかも、配線の微細化などに対しても、柔軟に適用できるようにした電解処理装置及び方法を提供することを目的とする。
【００１８】
【課題を解決するための手段】
請求項１に記載の発明は、基板を保持する基板保持部と該基板保持部で保持した基板に対向した位置に配置された対極板とを備え、前記基板保持部で保持した基板と前記対極板との間に電解液を満たしつつ給電して電解処理を行う電解処理ユニットと、異なる種類の電解液を供給する複数の電解液供給設備を備え、前記電解処理ユニットは、前記複数の電解液供給設備の一つと択一的に接続できるように構成されていることを特徴とする電解処理装置である。
【００１９】
このように、異なる電解液を供給する複数の電解液供給設備の一つに電解液処理ユニットを択一的に接続することで、電解処理装置としてのフレキシビリティを高めることができる。なお、単一の電解処理ユニットに化学性状の異なる複数の薬液（電解液）を供給するため、液切替え時に、必要に応じた洗浄、ブロー、共洗いなどの措置が必要となるが、これらの作業はいずれも簡単に自動化が可能である。なお、薬液（電解液）によっては、これらの液切替えに伴う諸作業が不要な場合もある。
【００２０】
請求項２に記載の発明は、前記電解処理ユニットに接続する前記電解液供給設備を任意に選択する信号を入力する入力装置を有することを特徴とする請求項１記載の電解処理装置である。
これにより、例えば、基板の種類、基板の処理対象レイヤー、基板の処理経過時間等の基板に関する情報をオペレーターが自動または画面等で入力することで、この情報に基づいて、適切な電解液を適切なタイミングで切替ることが可能となる。従って、基板毎、レイヤー毎の電解液の変更が可能となり、更には一つのレイヤー上に異なる電解処理を施すことも可能となる。
【００２１】
請求項３に記載の発明は、基板が配線基板であり、基板上の電解処理対象物が銅を含有する金属であることを特徴とする請求項１または２記載の電解処理装置である。
本発明は、主にＬＳＩ分野で使用されると考えられ、その場合は、微細配線の主材料である銅に係わる電解処理を行うのに有効な装置となる。なお、処理材料は銅系材料に限定されるものでなく、めっきやエッチング、あるいは電着も含めた電解処理を行う場合に有効な装置である。適用分野についても、ＬＳＩに限定されることはなく、同様な原理機構に基づく加工工業において有効に使われる。
【００２２】
請求項４に記載の発明は、基板を搬送する搬送装置と、基板を保持する基板保持部と該基板保持部で保持した基板に対向した位置に配置された対極板とを備え、前記基板保持部で保持した基板と前記対極板との間に電解液を満たしつつ給電して電解処理を行う複数の電解処理ユニットと、異なる種類の電解液を保持し供給する複数の電解液供給設備を備え、前記各電解処理ユニットは、前記複数の電解液供給設備の任意の一つと択一的に接続できるように構成されていることを特徴とする電解処理装置である。
【００２３】
このように、電解処理装置の内部にフレキシブルな電解処理ユニットを複数収納することにより、より多様な用途での使用が可能となる。なお、電解液供給設備は、必ずしも装置である必要はなく、例えば生産工場のインフラからラインで供給される形態であっても良い。
【００２４】
請求項５に記載の発明は、前記各電解処理ユニットに接続する前記各電解液供給設備を任意に選択する信号を入力する入力装置を有することを特徴とする請求項４記載の電解処理装置である。
例えば、基板の生産枚数が非常に少ない時は、１台の電解処理装置内の複数電解処理ユニットを稼動させることで、多様な要求を満足する基板の製造が可能である。生産枚数が多くなった場合には、要求スペックに応じて、必要な台数の基板処理装置を稼動させ、更に各基板処理装置内の電解処理ユニットを細かく振り分けて使用することによって、生産効率を最大に高めることが可能である。
【００２５】
請求項６に記載の発明は、基板を洗浄する洗浄ユニットを更に有することを特徴とする請求項４または５記載の電解処理装置である。
電解処理装置は、一般に物質表面の繊細な加工処理を行う装置である。このため、基板を洗浄する洗浄ユニットとして、高機能なものを使用することが好ましい。また、電解処理後の金属膜の結晶を安定化させるために、アニールなどの加熱ユニットを装置内に配置するようにしてもよい。
また本発明は、超微細なＬＳＩ配線のように、一液での電解処理が困難な場合に一般に使われるものであり、このため、例えば線幅が０．１５μｍ未満の配線を有する基板を処理する場合に特に有効である。
【００２６】
請求項７に記載の発明は、基板と該基板に対向した位置に配置される対極板との間に第１処理液を満たしつつ給電して第１電解処理を行い、基板と前記対極板との間に前記第１電解液とは異なる第２電解液を満たしつつ給電して第２電解処理を行うことを特徴とする電解処理方法である。
【００２７】
請求項８に記載の発明は、前記第１電解処理と前記第２電解処理の間に、基板と前記対極板との間に残った前記第１電解液を洗浄し乾燥させることを特徴とする請求項７記載の電解処理方法である。
請求項９に記載の発明は、前記第１電解液及び前記第２電解液は、複数の異なる種類の電解液から選択された任意の電解液であることを特徴とする請求項７または８記載の電解処理方法である。
【００２８】
【発明の実施の形態】
以下、本発明の実施の形態を図面を参照して説明する。なお、以下の各例では、本発明を電解めっき装置に適用した例を示しているが、基板と対極板の間に、電流の流れる方向を逆にした電圧を印加しつつ電解液を供給することで、電解エッチング装置として使用できることは勿論である。
【００２９】
図１は、本発明の実施の形態における電解めっき装置（電解処理装置）を示す概略断面図である。図１に示すように、この電解めっき装置は、電解めっきユニット３０と、この電解めっきユニット３０に電解液としてめっき液を供給し回収する２つのめっき液供給設備３２ａ，３２ｂを備え、更に、制御部３４と、この制御部３４に信号を入力する、例えばキーボード等からなる入力装置３６を備えている。
【００３０】
電解めっきユニット３０は、この例は、上下動かつ回転自在で、表面を下向き（フェースダウン）にして基板Ｗを着脱自在に保持する該基板保持部４０と、内部にめっき液（電解液）を保持するめっき槽４２とを上下に備えている。めっき槽４２の内部には、隔壁４４で周囲を仕切られ上部に隔膜４６を取付けた対極板室４８が区画形成されており、この対極板室４８の内部に、基板Ｗと対極となる対極板（めっき装置にあってはアノード）５０が基板Ｗと対向した位置に配置されている。そして、基板保持部４０で保持した基板Ｗの表面に形成されたシード層７（図４（ａ）参照）等の導電体と対極板５０との間に、導電体を陰極、対極板５０を陽極としためっき電圧を印加して、めっき電流を流す電源５１が備えられている。
【００３１】
なお、電解エッチング装置にあっては、前述のように、基板保持部４０で保持した基板Ｗの表面に形成されたシード層７（図４（ａ）参照）等の導電体と対極板５０との間に、導電体を陽極、対極板５０を陰極としためっき電圧を印加して、めっき電流を流す。
【００３２】
一方のめっき液供給設備３２ａは、例えばピロりん酸銅めっき液等の第１めっき液を保持し供給するたもめのもので、このめっき液供給設備３２ａから延びるめっき液供給ライン５２ａとめっき液排出ライン５４ａは、電解めっきユニット３０のめっき槽４２に接続され、これらのめっき液供給ライン５２ａ及びめっき液排出ライン５４ａの内部には、開閉弁５６ａ，５８ａがそれぞれ介装されている。
【００３３】
他方のめっき液供給設備３２ｂは、例えば硫酸銅めっき液等の第２めっき液を保持し供給するたもめのもので、このめっき液供給設備３２ｂから延びるめっき液供給ライン５２ｂとめっき液排出ライン５４ｂは、電解めっきユニット３０のめっき槽４２に接続され、これらのめっき液供給ライン５２ｂ及びめっき液排出ライン５４ｂの内部には、開閉弁５６ｂ，５８ｂがそれぞれ介装されている。
【００３４】
ここで、めっき液供給ライン５２ａ，５２ｂは、めっき槽４２の底部に該めっき槽４２の側壁と隔壁４４で挟まれた位置で接続され、めっき液排出ライン５４ａ，５４ｂは、めっき槽４２の上部に接続されている。これにより、めっき槽４２内に供給されためっき液は、めっき槽４２の側壁と隔壁４４で挟まれた領域に沿って流れてめっき槽４２内を満たし、めっき槽４２の上部から排出されて循環するようになっており、基板Ｗと対極板５０との間に隔膜４６を配置することで、めっき槽４２内に供給されためっき液が対極板５０の表面に直接当たって、対極板５０の表面に形成されたブラックフィルム等がめっき液によって巻き上げられ流れ出すことが防止される。なお、隔膜４６は、通水性を有する、例えば織布や不織布で構成されるが、この隔膜４６の代わりに、内部に多数の細孔を有するプレートを使用してもよい。
【００３５】
前記開閉弁５６ａ，５８ａ、５６ｂ，５８ｂは、制御部３４から出力される出力信号により開閉制御される。また、制御部３４には、入力装置３６を使って、または自動で、例えば、基板の種類、基板の処理対象レイヤー、基板の処理経過時間等の基板に関する任意の情報が入力される。
【００３６】
次に、この電解めっき装置の使用例について、例えば図４（ａ）及び（ｂ）に示す、基板Ｗの表面に形成した微孔３及び配線溝４内に銅を充填する場合を例にして説明する。
先ず、図４（ａ）に示すように、導電層１ａの内部に微孔３や配線溝４等の配線用の微細凹部を形成し、その上にＴａＮ等からなるバリア層５、更にその上に電解めっきの給電層としてシード層７を形成した基板Ｗを、その表面を下向きにして基板保持部４０で保持し、この基板保持部４０で保持した基板Ｗをめっき槽４２の上端開口部を閉塞する所定の位置まで下降させて停止させる。
【００３７】
この状態で、例えばピロりん酸銅めっき液等の第１めっき液を保持し供給するめっき液供給設備３２ａから延びるめっき液供給ライン５２ａとめっき液排出ライン５４ａに介装した開閉弁５６ａ，５８ａを開いて、第１めっき液をめっき槽４２内に供給し循環させ、これによって、対極板５０を第１めっき液中に浸漬させ、基板保持部４０で保持した基板Ｗの表面を第１めっき液に接触させる。この状態で、基板保持部４０で保持した基板Ｗの表面に形成されたシード層７と対極板５０との間に、シード層７を陰極、対極板５０を陽極としためっき電圧を印加して、めっき電流を流し、必要に応じて基板Ｗを回転させることで、基板Ｗの表面に電解めっきを行う。そして、所定の時間に亘る電解めっきを行って、シード層７を補強乃至補修して、シード層７を完全なものとする。
【００３８】
そして、シード層７と対極板５０との間のめっき電圧の印加を解いて、第１めっき液による電解めっきを終了させる。しかる後、めっき液供給ライン５２ａとめっき液排出ライン５４ａを介してめっき槽４２内の第１めっき液を引き抜き、必要に応じて、第１めっき液による電解めっき後の基板Ｗの表面及びめっき槽４２の内部を純水等で洗浄し乾燥させる。
【００３９】
次に、第１めっき液を保持し供給するめっき液供給設備３２ａから延びるめっき液供給ライン５２ａとめっき液排出ライン５４ａに介装した開閉弁５６ａ，５８ａを閉じ、硫酸銅めっき液等の第２めっき液を保持し供給するめっき液供給設備３２ｂから延びるめっき液供給ライン５２ｂとめっき液排出ライン５４ｂに介装した開閉弁５６ｂ，５８ｂを開いて、第２めっき液をめっき槽４２内に供給し循環させ、これによって、対極板５０を第２めっき液中に浸漬させ、基板保持部４０で保持した基板Ｗの表面を第２めっき液に接触させる。この状態で、基板保持部４０で保持した基板Ｗの表面に形成されたシード層７と対極板５０との間に、シード層７を陰極、対極板５０を陽極としためっき電圧を印加して、めっき電流を流し、必要に応じて基板Ｗを回転させることで、基板Ｗの表面に電解めっきを行う。そして、所定の時間に亘る電解めっきを行って、図４（ｂ）に示すように、微孔３や配線溝４等の配線用の微細凹部内に銅を充填するとともに、酸化膜２上に銅膜６を堆積する。
【００４０】
そして、シード層７と対極板５０との間のめっき電圧の印加を解いて、第２めっき液による電解めっきを終了させる。しかる後、めっき液供給ライン５２ｂとめっき液排出ライン５４ｂを介してめっき槽４２内の第２めっき液を引き抜き、必要に応じて、第２めっき液による電解めっき後の基板Ｗの表面及びめっき槽４２の内部を純水等で洗浄し乾燥させて、めっき処理を終了する。
【００４１】
図２は、本発明の他の実施の形態における電解めっき装置（電解処理装置）を示す概略断面図であり、図１に示す例と異なる点は以下の通りである。
すなわち、この例は、電解めっきユニット６０として、上下動かつ回転自在で、表面を上向き（フェースアップ）にして基板Ｗを着脱自在に保持する基板保持部６２と、この基板保持部６２の上方の該基板保持部６２で保持した基板Ｗの周縁部を囲繞する位置に配置されたシール材６４と、上下動及び回転自在で、基板保持部６２の上方に配置された電極ヘッド６６を有するものを使用している。この電極ヘッド６６は、下方に開口し、内部に対極板６８を配置するとともに、下端開口部に隔膜７０を取付け、内部をめっき液室７２としたハウジング７４が備えられている。その他の構成は、図１に示すものと同様である。
【００４２】
この例にあっては、基板保持部６２で表面を上向きにして保持した基板Ｗを上昇させて該基板Ｗの周縁部をシール材６４に圧接させてここを水密的にシールし、これによって、基板Ｗ及びシール材６４でめっき液を保持するめっき槽７６を区画する。そして、基板保持部６２で保持した基板Ｗの上面（表面）と隔膜７０の下面との間の隙間が所定の値となるように電極ヘッド６６を下降させる。この状態で、基板Ｗとシール材６４で区画形成されためっき槽７６にめっき液を供給し、めっき液室７２内をめっき液で満たしながらめっき液を循環させ、例えば、基板保持部６２で保持した基板Ｗの表面に形成されたシード層７（図４（ａ）参照）と対極板６８との間に、シード層７を陰極、対極板６８を陽極としためっき電圧を電源５１を介して印加して、めっき電流を流し、必要に応じて基板Ｗを及び隔膜７０を回転させることで、基板Ｗの表面に電解めっきを行う。この時、前述と同様に、めっき液供給設備３２ａに保持されて供給される第１めっき液による電解めっきと、めっき液供給設備３２ｂに保持されて供給される第２めっき液による電解めっきとの切替えを行う。
【００４３】
図３は、図１（または図２）に示す電解めっきユニット（電解処理ユニット）３０（６０）を複数備えた、本発明の他の実施の形態における電解めっき装置（電解処理装置）の全体平面図を示す。
【００４４】
この例は、例えばスミフボックス等の内部に多数の半導体ウエハ等の基板を収納した搬送ボックス１０を着脱自在な矩形状のハウジング１２を備えている。このハウジング１２の内部には、置台１４と、例えば図１または図２に示す４台の電解めっきユニット３０（６０）と、中間洗浄または後洗浄の少なくとも一方を行う２台の洗浄ユニット２８が収納され、更に搬送ボックス１０及び置台１４との間で基板を搬送する搬送装置としての第１搬送ロボット２０と、置台１４、電解めっきユニット３０（６０）、洗浄ユニット２８との間で基板を搬送する搬送装置としての第２搬送ロボット２２が備えられている。
【００４５】
そして、前述と同様な構成の例えばピロりん酸銅めっき液等の第１めっき液を保持し供給するめっき液供給設備３２ａと、例えば硫酸銅めっき液等の第２めっき液を保持し供給するめっき液供給設備３２ｂが備えられている。そして、めっき液供給設備３２ａから延びるめっき液供給ライン５２ａとめっき液排出ライン５４ａは、各電解めっきユニット３０（６０）のめっき槽４２（７６）（図１及び図２参照、以下同じ）にそれぞれ個別に接続され、これらのめっき液供給ライン５２ａ及びめっき液排出ライン５４ａは、この内部に介装した開閉弁５６ａ，５８ａを介して、個別に開閉できるようになっている。めっき液供給設備３２ｂから延びるめっき液供給ライン５２ｂとめっき液排出ライン５４ｂも同様に、各電解めっきユニット３０（６０）のめっき槽４２（７６）にそれぞれ個別に接続され、これらのめっき液供給ライン５２ｂ及びめっき液排出ライン５４ｂは、この内部に介装した開閉弁５６ｂ，５８ｂを介して、個別に開閉できるようになっている。
【００４６】
前記開閉弁５６ａ，５８ａ、５６ｂ，５８ｂは、制御部３４から出力される出力信号により開閉制御され、また、制御部３４には、入力装置３６を使って、または自動で、例えば、基板の種類、基板の処理対象レイヤー、基板の処理経過時間等の基板に関する任意の情報が入力されるようになっていることは前述と同様である。
【００４７】
この例によれば、基板を収納した搬送ボックス１０から１枚の基板が第１搬送ロボット２０により取出され、置台１４上に載置される。そして、この置台１４に載置された基板は、第２搬送ロボット２２によって、いずれかの電解めっきユニット３０（６０）に搬送され、この電解めっきユニット３０（６０）で、前述と同様に、例えば第１めっき液を使用しためっきが行われる。そして、このめっき後の基板は、必要に応じて、いずれかの洗浄ユニット２８に搬送されて中間洗浄させた後、再度電解めっきユニット３０（６０）に戻され、この電解めっきユニット３０（６０）で、前述と同様に、例えば第２めっき液を使用しためっきが行われる。このめっき後の基板は、第２搬送ロボット２２によって、洗浄ユニット２８に搬送され、この洗浄ユニット２８で後洗浄及び後洗浄後のスピン乾燥が行われる。そして、このスピン乾燥後の基板は、第２搬送ロボット２２によって、置台１４に搬送されて載置され、この置台１４上に載置された基板は、第１搬送ロボット２０によって、搬送ボックス１０内の元の位置に戻される。
【００４８】
これらの電解液の選択は、処理する基板の仕様、枚数、レイヤーなどにより、入力装置３６を使って選択可能である。例えば、基板の種類、基板の処理対象レイヤー、基板の処理経過時間等の基板に関する任意の情報をオペレーターが入力装置３６を使って画面等で入力することで、この情報に基づいて、適切な電解液を適切なタイミングで切替ることが可能となる。従って、基板毎、レイヤー毎の電解液の変更が可能となり、更には一つのレイヤー上に異なる電解処理を施すことも可能となる。
【００４９】
この例では、これらの自由度を、各電解めっきユニット３０（６０）に対して独立的に与えることで、処理形態は非常に多様になる。また、洗浄ユニット２８では、電解処理後の洗浄のみならず、電解途中の洗浄を実施するようにしてもよい。搬送ボックス１０については、処理対象基板の汚染度により、電解めっき装置への搬入と搬出で使い分けることも可能である。
【００５０】
このように、本発明は、複数の電解液を効率的に使用することができる。また本発明における電解液は、めっき液、エッチング液、電着液のいずれもが使用可能である。更に、１つの基板あるいは１つのレイヤーに対して、複数のめっき液のみならず、めっき液とエッチング液のような組合せで処理することもできる。さらに、対極板室をめっき槽と区分して設けることにより、基板を処理する電解液と対極板室内に導入する対極液を区分し、電解処理の用途を更に拡張することができる。
【００５１】
【発明の効果】
以上説明したように、本発明によれば、多様な仕様の製品に対して、その生産量を加味しながら最も生産性の高い状態での生産が可能となり、生産コストの削減を図ることができる。しかも、配線の微細化などに対しても、柔軟に適用できるようにした電解処理装置及び方法を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態における電解めっき装置に適用した電解加工装置の概略断面図である。
【図２】本発明の他の実施の形態における電解めっき装置に適用した電解加工装置の概略断面図である。
【図３】本発明の他の実施の形態における複数の電解めっきユニット（電解処理ユニット）を備えた電解めっき装置に適用した電解処理装置の全体平面図である。
【図４】銅配線基板の形成例を工程順に示す図である。
【図５】従来の電解めっき装置の全体平面図である。
【図６】従来の他の電解めっき装置の全体平面図である。
【符号の説明】
１０搬送ボックス
１２ハウジング
２０，２２搬送ロボット
３０，６０電解めっきユニット（電解処理ユニット）
３２ａ，３２ｂめっき液（電解液）供給設備
３４制御部
３６入力装置
４０，６２基板保持部
４２，７６めっき槽
４６，７０隔膜
５０，６８対極板
５１電源
５２ａ，５２ｂめっき液供給ライン
５４ａ，５４ｂめっき液排出ライン
５６ａ，５６ｂ，５８ａ，５８ｂ開閉弁
６４シール材
６６電極ヘッド[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrolytic processing apparatus and method, and particularly to forming a wiring material such as copper by plating on a surface of a substrate on which a fine wiring pattern (dent) is formed, or forming a metal film formed on the surface of the substrate. The present invention relates to an electrolytic treatment apparatus and method used for removing by electrolytic etching.
[0002]
[Prior art]
In recent years, a trend of using copper (Cu) having low electric resistivity and high electromigration resistance instead of aluminum or aluminum alloy as a wiring material for forming electric wiring on a semiconductor substrate has become remarkable. Copper is generally difficult to form wiring shapes by anisotropic etching like aluminum, so this type of copper wiring is formed by so-called copper damascene technology, in which copper is embedded in fine recesses provided on the surface of the substrate. Generally formed. As a method of forming the copper wiring, there are methods such as CVD, sputtering and plating. In any case, a copper film is formed on almost the entire surface of the substrate, and the film is formed by chemical mechanical polishing (CMP) or electrolytic etching. Unnecessary copper is removed.
[0003]
FIG. 4 shows a manufacturing example of this type of copper wiring board W in the order of steps. First, as shown in FIG. 4 (a), on a conductive layer 1a on a semiconductor substrate 1 on which a semiconductor element is formed. SiO ₂ An oxide film 2 is deposited, and fine recesses for wiring such as fine holes (via holes) 3 and wiring trenches (trench) 4 are formed by lithography / etching technology, and a barrier layer 5 made of TaN or the like is further formed thereon. A seed layer 7 is formed thereon as a power supply layer for electrolytic plating.
[0004]
Then, as shown in FIG. 4B, the surface of the substrate W is plated with copper, so that the fine holes 3 and the wiring grooves 4 of the semiconductor substrate 1 are filled with copper, and the copper is deposited on the oxide film 2. A film 6 is deposited. Thereafter, the copper film 6 and the barrier layer 5 on the oxide film 2 are removed by chemical mechanical polishing (CMP) or electrolytic etching, and the surface of the copper film 6 filled in the micropores 3 and the wiring grooves 4 is oxidized. The surface of the film 2 is made substantially flush with the surface. As a result, a wiring made of the copper film 6 is formed as shown in FIG.
As described above, as the wiring material changes from aluminum to copper, an electrolytic plating apparatus that performs plating of a copper material and an electrolytic etching apparatus that performs electrolytic etching of a copper film have attracted attention.
[0005]
FIG. 5 shows a conventional general electrolytic plating apparatus used for manufacturing copper wiring. The electroplating apparatus includes a rectangular housing 12 in which a transfer box 10 containing a large number of substrates such as semiconductor wafers can be detachably mounted, for example, inside a smif box. A table 14, four electrolytic plating units 16, and two post-cleaning units 18 are housed inside the housing 12, and further serve as a transfer device for transferring a substrate between the transfer box 10 and the table 14. And a second transfer robot 22 as a transfer device for transferring a substrate between the first transfer robot 20 and the table 14, the electrolytic plating unit 16 and the post-cleaning unit 18.
[0006]
Then, a single plating solution supply facility 24 common to the four electrolytic plating units 16 is provided, and a common plating solution is individually supplied to each electrolytic plating unit 16 from the plating solution supply facility 24 and collected. It has become.
[0007]
As a result, one substrate is taken out from the transport box 10 containing the substrates by the first transport robot 20 and placed on the mounting table 14. Then, the substrate placed on the mounting table 14 is transported by the second transport robot 22 to any one of the electrolytic plating units 16, where electrolytic plating such as copper plating is performed. The plated substrate is transported by the second transport robot 22 to any one of the post-cleaning units 18, where the post-cleaning of the substrate and spin drying after the post-cleaning are performed. Then, the substrate after the spin drying is transferred to and placed on the mounting table 14 by the second transfer robot 22, and the substrate mounted on the mounting table 14 is moved by the first transfer robot 20 into the transfer box 10. Is returned to its original position.
[0008]
The line width of wiring in current copper wiring and the like is generally in the range of 0.15 to 100 μm, and a plating solution used in an electrolytic plating apparatus is composed of copper sulfate, sulfuric acid, hydrochloric acid, a suppressor, an accelerator, and a leveler. It is common to use The plating solution used in one electrolytic plating apparatus is usually one type.
[0009]
On the other hand, primary plating is performed by electrolytic plating or electroless plating using a highly polarized solution such as copper pyrophosphate plating solution to reinforce or repair the seed layer 7 (see FIG. 4 (a)) to complete the plating. It has been proposed that the copper wiring be buried by performing a secondary plating using a copper sulfate plating solution. It is also known to supply a plurality of types of copper sulfate plating solutions having different embedding characteristics to one electrolytic plating apparatus to perform multi-stage plating.
[0010]
FIG. 6 shows a conventional example of an electrolytic plating apparatus for performing such multi-stage plating. In this example, two-stage plating is performed. For example, a first plating solution supply facility 24a that supplies a first plating solution such as a copper pyrophosphate plating solution and a second plating solution supply device 24a such as a copper sulfate plating solution. A second plating solution supply facility 24b for supplying a plating solution is provided. On the other hand, the electrolytic plating unit 16 is also connected to the first plating solution supply facility 24a to perform first electrolytic plating using the first plating solution. The second electrolytic plating unit 16b is connected to the unit 16a and the second plating solution supply equipment 24b and performs plating using the second plating solution. Further, a post-cleaning unit 18 and an intermediate cleaning unit 26 are provided as cleaning units.
[0011]
Thereby, the substrate placed on the mounting table 14 in the same manner as described above is transported to any one of the first electrolytic plating units 16a, where the primary plating using the first plating solution is performed, and then the second plating is performed. The wafer is transferred to the intermediate cleaning unit 26 by the transfer robot 22, where the intermediate cleaning is performed. Then, the substrate after the intermediate cleaning is transported by the second transport robot 22 to any one of the second electrolytic plating units 16b, where the secondary plating using the second plating solution is performed. Similarly, after the post-washing and the spin drying, the wafer is returned into the transport box 10.
[0012]
As described above, when a different electrolytic plating unit is used for each different plating solution and plating using two or more types of plating solutions is not performed in a single electrolytic plating unit, a trace amount of additive is mixed. This is to prevent the plating characteristics from becoming unstable.
[0013]
[Problems to be solved by the invention]
For example, in the field of LSI, the development of an ultra-fine wiring forming technology of 0.15 μm or less has already been developed. In this case, further miniaturization and high aspect ratio are required for the embedding characteristics of the electrolytic plating method, and development of a plating solution is facing a difficult technical problem.
[0014]
However, the ultrafine wiring technology is a technology mainly used for local wiring, which is a lower layer portion of a multilayer wiring, and is not necessarily a costly technology for forming a low-aspect global wiring having a line width of about 10 to 100 μm. Likely not technically optimal. This is because the plating characteristics required for global wiring are the flat finish of the plating upper surface, that is, the so-called leveling property, whereas the plating characteristics required for local wiring are that copper is buried in minute recesses by voidless. That is, it is because the wiring material can be embedded in the fine concave portions having a high aspect ratio. At present, a plating solution that can simultaneously satisfy these different requirements has not yet been developed.
[0015]
Also, for example, semiconductor devices that require copper wiring are often required to produce a large number of products in small lots, and furthermore, depending on the semiconductor device, the wiring width, the number of laminated layers, their composition ratio, and the like are generally not constant. . For this reason, it is difficult to form wirings of all layers with one kind of plating solution and to efficiently produce various devices as in a conventional electrolytic plating apparatus. Even if an apparatus configuration that can use a plurality of types of plating solutions is adopted, an operation method that specifies a different electrolytic plating unit for each plating solution can only be performed with inflexible operation, and increases production costs. Leads to
[0016]
The case of the electrolytic plating apparatus for performing the copper plating has been described above, but the same applies to the electrolytic etching apparatus that performs the reverse process of the plating. That is, the characteristics of electrolytic etching can be adjusted by additives and electrolytes as in the case of the plating solution in the electrolytic plating apparatus, but the process requirements required for the upper and lower layers of the multilayer wiring are not uniform. Further, there are various requirements for in-plane uniformity and etching rate, and these requirements are increasingly varied depending on not only the wiring width but also the wiring sparse density, cross-sectional shape, and the like. For this reason, development of an apparatus that can flexibly operate different electrolytic etching solutions has been required.
[0017]
The present invention has been made in view of the above circumstances, and it is possible to produce products of various specifications in the state of the highest productivity while taking into account the amount of production, thereby reducing production costs. It is another object of the present invention to provide an electrolytic processing apparatus and method which can be flexibly applied to fine wiring and the like.
[0018]
[Means for Solving the Problems]
The invention according to claim 1 includes a substrate holding portion for holding a substrate, and a counter electrode plate disposed at a position facing the substrate held by the substrate holding portion, wherein the substrate held by the substrate holding portion and the counter electrode are provided. An electrolytic processing unit that performs electrolytic processing by supplying power while filling an electrolytic solution between the plate and a plurality of electrolytic solution supply facilities for supplying different types of electrolytic solutions, wherein the electrolytic processing unit includes the plurality of electrolytic solutions. An electrolytic treatment apparatus characterized by being configured to be selectively connected to one of supply facilities.
[0019]
As described above, by selectively connecting the electrolytic solution processing unit to one of a plurality of electrolytic solution supply facilities for supplying different electrolytic solutions, the flexibility of the electrolytic treatment apparatus can be improved. In order to supply a plurality of chemical solutions (electrolyte solutions) having different chemical properties to a single electrolytic treatment unit, it is necessary to take necessary measures such as washing, blowing, and co-washing when switching the solutions. All operations can be easily automated. In addition, depending on a chemical solution (electrolyte solution), there may be cases where various operations involved in switching these solutions are unnecessary.
[0020]
The invention according to claim 2 is the electrolytic processing apparatus according to claim 1, further comprising an input device for inputting a signal for arbitrarily selecting the electrolytic solution supply equipment connected to the electrolytic processing unit.
Thereby, for example, by inputting information about the substrate such as the type of the substrate, the layer to be processed of the substrate, the elapsed processing time of the substrate, etc. automatically or on a screen or the like, an appropriate electrolytic solution is appropriately determined based on the information. It is possible to switch at an appropriate timing. Therefore, it is possible to change the electrolytic solution for each substrate and each layer, and it is also possible to perform different electrolytic treatments on one layer.
[0021]
According to a third aspect of the present invention, there is provided the electrolytic processing apparatus according to the first or second aspect, wherein the substrate is a wiring substrate, and the object to be subjected to the electrolytic treatment on the substrate is a metal containing copper.
The present invention is considered to be mainly used in the field of LSI, and in that case, it is an effective device for performing an electrolytic treatment on copper which is a main material of fine wiring. Note that the processing material is not limited to a copper-based material, and is an effective apparatus when performing electrolytic processing including plating, etching, or electrodeposition. The application field is not limited to the LSI, and is effectively used in the processing industry based on the same principle mechanism.
[0022]
According to a fourth aspect of the present invention, there is provided a transfer device for transferring a substrate, a substrate holding unit for holding the substrate, and a counter electrode plate disposed at a position facing the substrate held by the substrate holding unit, A plurality of electrolytic processing units that perform electrolytic processing by supplying power while filling the electrolytic solution between the substrate held by the section and the counter electrode plate, and a plurality of electrolytic solution supply facilities that hold and supply different types of electrolytic solutions Each of the electrolytic processing units is configured to be selectively connected to any one of the plurality of electrolytic solution supply facilities.
[0023]
As described above, by accommodating a plurality of flexible electrolytic processing units inside the electrolytic processing apparatus, it is possible to use the electrolytic processing apparatus in various applications. Note that the electrolytic solution supply equipment does not necessarily need to be a device, and may be a form supplied from a production plant infrastructure via a line, for example.
[0024]
The invention according to claim 5 has an input device for inputting a signal for arbitrarily selecting each of the electrolytic solution supply facilities connected to each of the electrolytic processing units. is there.
For example, when the number of substrates to be produced is extremely small, by operating a plurality of electrolytic processing units in one electrolytic processing apparatus, it is possible to manufacture substrates that satisfy various requirements. When the production number increases, the required number of substrate processing units are operated according to the required specifications, and the electrolytic processing units in each substrate processing unit are finely divided and used to maximize production efficiency. It is possible to increase.
[0025]
The invention according to claim 6 is the electrolytic processing apparatus according to claim 4 or 5, further comprising a cleaning unit for cleaning the substrate.
An electrolytic processing apparatus is an apparatus that generally performs delicate processing of a material surface. Therefore, it is preferable to use a high-performance cleaning unit for cleaning the substrate. Further, in order to stabilize the crystal of the metal film after the electrolytic treatment, a heating unit for annealing or the like may be arranged in the apparatus.
Also, the present invention is generally used when it is difficult to perform electrolytic treatment with one liquid, such as ultra-fine LSI wiring. For this reason, for example, a substrate having a wiring having a line width of less than 0.15 μm is processed. It is particularly effective when doing so.
[0026]
The invention according to claim 7, wherein the first electrolytic treatment is performed by supplying power while filling the first processing liquid between the substrate and the counter electrode plate disposed at a position facing the substrate, and performing the first electrolytic treatment on the substrate and the counter electrode plate. And supplying power while filling a second electrolytic solution different from the first electrolytic solution during the second electrolytic treatment to perform the second electrolytic treatment.
[0027]
The invention according to claim 8 is characterized in that the first electrolytic solution remaining between the substrate and the counter electrode plate is washed and dried between the first electrolytic treatment and the second electrolytic treatment. An electrolytic treatment method according to claim 7.
The invention according to claim 9 is characterized in that the first electrolytic solution and the second electrolytic solution are arbitrary electrolytic solutions selected from a plurality of different types of electrolytic solutions. Is an electrolytic treatment method.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following examples, an example in which the present invention is applied to an electrolytic plating apparatus is shown. However, by supplying a voltage between the substrate and the counter electrode plate while applying a voltage in which the direction of current flow is reversed, the electrolytic solution is supplied. Of course, it can be used as an electrolytic etching apparatus.
[0029]
FIG. 1 is a schematic sectional view showing an electrolytic plating apparatus (electrolytic processing apparatus) according to an embodiment of the present invention. As shown in FIG. 1, the electrolytic plating apparatus includes an electrolytic plating unit 30 and two plating solution supply facilities 32a and 32b for supplying and recovering a plating solution as an electrolytic solution to the electrolytic plating unit 30. The control unit 34 includes a unit 34 and an input device 36 such as a keyboard.
[0030]
In this example, the electroplating unit 30 is vertically movable and rotatable, and has a substrate holding portion 40 that detachably holds the substrate W with its surface facing downward (face down), and a plating solution (electrolytic solution) inside. A plating tank 42 for holding is provided above and below. Inside the plating tank 42, a counter electrode chamber 48 is formed by partitioning the periphery with a partition wall 44 and having a diaphragm 46 attached to an upper portion thereof. In the counter electrode chamber 48, a counter electrode plate (plating) serving as a counter electrode to the substrate W is formed. In the apparatus, an anode 50 is arranged at a position facing the substrate W. Then, between the conductor such as the seed layer 7 (see FIG. 4A) formed on the surface of the substrate W held by the substrate holding unit 40 and the counter electrode plate 50, the conductor is used as a cathode and the counter electrode plate 50 is formed. A power supply 51 for applying a plating voltage as an anode and passing a plating current is provided.
[0031]
In the electrolytic etching apparatus, as described above, the conductor such as the seed layer 7 (see FIG. 4A) formed on the surface of the substrate W held by the substrate holding unit 40 and the counter electrode plate 50 During this time, a plating current is applied by applying a plating voltage using the conductor as an anode and the counter electrode plate 50 as a cathode.
[0032]
One plating solution supply facility 32a is for holding and supplying a first plating solution such as a copper pyrophosphate plating solution. A plating solution supply line 52a extending from the plating solution supply facility 32a and a plating solution discharge line are provided. The line 54a is connected to the plating tank 42 of the electrolytic plating unit 30, and on-off valves 56a and 58a are interposed in the plating solution supply line 52a and the plating solution discharge line 54a, respectively.
[0033]
The other plating solution supply facility 32b is for holding and supplying a second plating solution such as, for example, a copper sulfate plating solution. The plating solution supply line 52b and the plating solution discharge line 54b extending from the plating solution supply facility 32b are provided. Are connected to the plating tank 42 of the electrolytic plating unit 30, and open / close valves 56b and 58b are interposed in the plating solution supply line 52b and the plating solution discharge line 54b, respectively.
[0034]
Here, the plating solution supply lines 52a and 52b are connected to the bottom of the plating bath 42 at a position sandwiched between the side wall of the plating bath 42 and the partition 44, and the plating solution discharge lines 54a and 54b are connected to the upper portion of the plating bath 42. It is connected to the. As a result, the plating solution supplied into the plating tank 42 flows along the region sandwiched between the side wall of the plating tank 42 and the partition 44, fills the plating tank 42, and is discharged from the upper part of the plating tank 42 and circulated. By arranging the diaphragm 46 between the substrate W and the counter electrode plate 50, the plating solution supplied into the plating tank 42 directly hits the surface of the counter electrode plate 50, The black film or the like formed on the surface is prevented from being wound up by the plating solution and flowing out. The diaphragm 46 is made of, for example, a woven fabric or a nonwoven fabric having water permeability. Instead of the diaphragm 46, a plate having a large number of pores therein may be used.
[0035]
The on-off valves 56a, 58a, 56b, 58b are controlled to open and close by an output signal output from the control unit 34. In addition, the control unit 34 receives, using the input device 36 or automatically, arbitrary information about the substrate, such as the type of the substrate, the layer to be processed of the substrate, and the elapsed processing time of the substrate.
[0036]
Next, an example of use of this electrolytic plating apparatus will be described with reference to, for example, a case where copper is filled in the fine holes 3 and the wiring grooves 4 formed on the surface of the substrate W as shown in FIGS. 4A and 4B. explain.
First, as shown in FIG. 4 (a), fine recesses for wiring such as fine holes 3 and wiring grooves 4 are formed inside the conductive layer 1a, and a barrier layer 5 made of TaN or the like is further formed thereon, and further thereon. A substrate W on which a seed layer 7 is formed as a power supply layer for electrolytic plating is held by a substrate holding unit 40 with its surface facing downward, and the substrate W held by the substrate holding unit 40 is closed at the upper end opening of a plating tank 42. It is lowered to a predetermined position to be closed and stopped.
[0037]
In this state, the on-off valves 56a and 58a interposed in the plating solution supply line 52a and the plating solution discharge line 54a extending from the plating solution supply facility 32a for holding and supplying the first plating solution such as a copper pyrophosphate plating solution are connected. After opening, the first plating solution is supplied into the plating tank 42 and circulated, whereby the counter electrode plate 50 is immersed in the first plating solution, and the surface of the substrate W held by the substrate holding unit 40 is cleaned with the first plating solution. Contact. In this state, a plating voltage is applied between the seed layer 7 formed on the surface of the substrate W held by the substrate holding unit 40 and the counter electrode plate 50, using the seed layer 7 as a cathode and the counter electrode 50 as an anode. Then, a plating current is passed, and the substrate W is rotated as necessary, thereby performing electrolytic plating on the surface of the substrate W. Then, electrolytic plating is performed for a predetermined time to reinforce or repair the seed layer 7, thereby completing the seed layer 7.
[0038]
Then, the application of the plating voltage between the seed layer 7 and the counter electrode plate 50 is released, and the electrolytic plating using the first plating solution is completed. Thereafter, the first plating solution in the plating tank 42 is pulled out through the plating solution supply line 52a and the plating solution discharge line 54a, and if necessary, the surface of the substrate W after the electrolytic plating with the first plating solution and the plating tank. The inside of 42 is washed with pure water or the like and dried.
[0039]
Next, the on / off valves 56a and 58a interposed between the plating solution supply line 52a and the plating solution discharge line 54a extending from the plating solution supply facility 32a for holding and supplying the first plating solution are closed, and the second solution such as a copper sulfate plating solution is closed. The plating solution supply line 52b extending from the plating solution supply facility 32b for holding and supplying the plating solution and the on / off valves 56b and 58b interposed in the plating solution discharge line 54b are opened to supply the second plating solution into the plating tank 42. Then, the counter electrode plate 50 is immersed in the second plating solution, and the surface of the substrate W held by the substrate holding unit 40 is brought into contact with the second plating solution. In this state, a plating voltage is applied between the seed layer 7 formed on the surface of the substrate W held by the substrate holding unit 40 and the counter electrode plate 50, using the seed layer 7 as a cathode and the counter electrode 50 as an anode. Then, a plating current is passed, and the substrate W is rotated as necessary, thereby performing electrolytic plating on the surface of the substrate W. Then, by performing electrolytic plating for a predetermined time, copper is filled into fine recesses for wiring such as fine holes 3 and wiring grooves 4 as shown in FIG. A copper film 6 is deposited.
[0040]
Then, the application of the plating voltage between the seed layer 7 and the counter electrode plate 50 is released, and the electrolytic plating using the second plating solution is completed. Thereafter, the second plating solution in the plating tank 42 is pulled out through the plating solution supply line 52b and the plating solution discharge line 54b, and if necessary, the surface of the substrate W after the electrolytic plating with the second plating solution and the plating tank. The inside of 42 is washed with pure water or the like and dried, and the plating process is completed.
[0041]
FIG. 2 is a schematic sectional view showing an electrolytic plating apparatus (electrolytic processing apparatus) according to another embodiment of the present invention, and the points different from the example shown in FIG. 1 are as follows.
That is, in this example, as the electrolytic plating unit 60, a substrate holding portion 62 that is vertically movable and rotatable, holds the substrate W detachably with its surface facing upward (face-up), and an upper portion of the substrate holding portion 62. One having a seal member 64 arranged at a position surrounding the peripheral edge of the substrate W held by the substrate holding part 62 and an electrode head 66 arranged vertically above and below the substrate holding part 62 so as to freely move up and down. I'm using The electrode head 66 is provided with a housing 74 that opens downward, has a counter electrode plate 68 disposed therein, has a diaphragm 70 attached to the lower end opening, and has a plating solution chamber 72 inside. Other configurations are the same as those shown in FIG.
[0042]
In this example, the substrate W held with the surface thereof facing upward by the substrate holding unit 62 is lifted, and the peripheral edge of the substrate W is pressed against the sealing material 64 to seal it water-tightly. A plating bath 76 for holding a plating solution is defined by the substrate W and the sealing material 64. Then, the electrode head 66 is lowered so that the gap between the upper surface (front surface) of the substrate W held by the substrate holding unit 62 and the lower surface of the diaphragm 70 has a predetermined value. In this state, the plating solution is supplied to the plating tank 76 defined by the substrate W and the sealing material 64, and the plating solution is circulated while filling the plating solution chamber 72 with the plating solution. A plating voltage using the seed layer 7 as a cathode and the counter electrode 68 as an anode is applied between the seed layer 7 (see FIG. 4A) formed on the surface of the substrate W thus formed and the counter electrode 68 via a power source 51. By applying the plating current, the substrate W and the diaphragm 70 are rotated as necessary to perform electrolytic plating on the surface of the substrate W. At this time, in the same manner as described above, the electrolytic plating using the first plating solution held and supplied to the plating solution supply facility 32a and the electrolytic plating using the second plating solution held and supplied to the plating solution supply facility 32b are performed. Perform switching.
[0043]
FIG. 3 is an overall plan view of an electrolytic plating apparatus (electrolytic processing apparatus) according to another embodiment of the present invention including a plurality of electrolytic plating units (electrolytic processing units) 30 (60) shown in FIG. 1 (or FIG. 2). The figure is shown.
[0044]
In this example, for example, a rectangular housing 12 in which a transfer box 10 accommodating a large number of substrates such as semiconductor wafers is detachably mounted inside a smif box or the like is provided. Inside the housing 12, the mounting table 14, for example, four electrolytic plating units 30 (60) shown in FIG. 1 or FIG. 2 and two cleaning units 28 for performing at least one of intermediate cleaning and post-cleaning are housed. Then, the substrate is further transferred between the first transfer robot 20 as a transfer device for transferring the substrate between the transfer box 10 and the mounting table 14, and between the mounting table 14, the electrolytic plating unit 30 (60), and the cleaning unit 28. A second transfer robot 22 as a transfer device is provided.
[0045]
Then, a plating solution supply facility 32a holding and supplying a first plating solution such as a copper pyrophosphate plating solution having the same configuration as described above, and a plating solution holding and supplying a second plating solution such as a copper sulfate plating solution are provided. A liquid supply facility 32b is provided. The plating solution supply line 52a and the plating solution discharge line 54a extending from the plating solution supply facility 32a are respectively connected to the plating tanks 42 (76) (see FIGS. 1 and 2; the same applies hereinafter) of each electrolytic plating unit 30 (60). The plating solution supply line 52a and the plating solution discharge line 54a are individually connected, and can be individually opened and closed via on-off valves 56a and 58a interposed therein. Similarly, a plating solution supply line 52b and a plating solution discharge line 54b extending from the plating solution supply facility 32b are also individually connected to the plating tanks 42 (76) of the electrolytic plating units 30 (60), respectively. 52b and the plating solution discharge line 54b can be individually opened and closed via on-off valves 56b and 58b interposed therein.
[0046]
The opening / closing valves 56a, 58a, 56b, 58b are controlled to open / close by an output signal output from the control unit 34. The control unit 34 uses the input device 36 or automatically, for example, the type of substrate. As described above, arbitrary information on the substrate, such as the substrate processing target layer and the substrate processing elapsed time, is input.
[0047]
According to this example, one substrate is taken out from the transport box 10 containing the substrates by the first transport robot 20 and placed on the table 14. Then, the substrate placed on the mounting table 14 is transported by the second transport robot 22 to any one of the electroplating units 30 (60). Plating using the first plating solution is performed. Then, the substrate after plating is transported to one of the cleaning units 28 to perform intermediate cleaning as necessary, and then returned to the electrolytic plating unit 30 (60) again, and the electrolytic plating unit 30 (60) is returned. Then, similarly to the above, plating using, for example, the second plating solution is performed. The substrate after the plating is transported by the second transport robot 22 to the cleaning unit 28, where post-cleaning and spin drying after the post-cleaning are performed. Then, the substrate after the spin drying is transferred to and placed on the mounting table 14 by the second transfer robot 22, and the substrate mounted on the mounting table 14 is moved by the first transfer robot 20 into the transfer box 10. Is returned to its original position.
[0048]
The selection of these electrolytes can be made using the input device 36 according to the specifications, number of sheets, layers, and the like of the substrate to be processed. For example, the operator inputs arbitrary information on the substrate, such as the type of the substrate, the processing target layer of the substrate, the elapsed processing time of the substrate, on a screen or the like using the input device 36, and based on this information, an appropriate electrolytic process is performed. The liquid can be switched at an appropriate timing. Therefore, it is possible to change the electrolytic solution for each substrate and each layer, and it is also possible to perform different electrolytic treatments on one layer.
[0049]
In this example, by giving these degrees of freedom to each of the electrolytic plating units 30 (60) independently, the processing form becomes very diverse. In the cleaning unit 28, not only cleaning after the electrolytic treatment but also cleaning during the electrolytic treatment may be performed. The transport box 10 can be selectively used for carrying in and out of the electrolytic plating apparatus depending on the degree of contamination of the substrate to be processed.
[0050]
Thus, the present invention can use a plurality of electrolyte solutions efficiently. Further, as the electrolytic solution in the present invention, any of a plating solution, an etching solution, and an electrodeposition solution can be used. Further, one substrate or one layer can be treated with a combination of a plating solution and an etching solution as well as a plurality of plating solutions. Further, by providing the counter electrode chamber separately from the plating tank, the electrolyte for treating the substrate and the counter electrode introduced into the counter electrode chamber can be separated to further expand the use of the electrolytic treatment.
[0051]
【The invention's effect】
As described above, according to the present invention, it is possible to produce a product having various specifications in a state of the highest productivity while taking the production amount into consideration, and it is possible to reduce the production cost. . In addition, it is possible to provide an electrolytic processing apparatus and method that can be flexibly applied to miniaturization of wiring and the like.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of an electrolytic processing apparatus applied to an electrolytic plating apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic sectional view of an electrolytic processing apparatus applied to an electrolytic plating apparatus according to another embodiment of the present invention.
FIG. 3 is an overall plan view of an electrolytic processing apparatus applied to an electrolytic plating apparatus having a plurality of electrolytic plating units (electrolytic processing units) according to another embodiment of the present invention.
FIG. 4 is a diagram showing an example of forming a copper wiring board in the order of steps.
FIG. 5 is an overall plan view of a conventional electrolytic plating apparatus.
FIG. 6 is an overall plan view of another conventional electroplating apparatus.
[Explanation of symbols]
10 Transport box
12 Housing
20,22 Transfer robot
30, 60 Electroplating unit (Electrolysis treatment unit)
32a, 32b Plating solution (electrolyte) supply equipment
34 control unit
36 Input device
40, 62 substrate holding part
42,76 Plating tank
46,70 diaphragm
50,68 Counter electrode
51 power supply
52a, 52b Plating solution supply line
54a, 54b Plating solution discharge line
56a, 56b, 58a, 58b On-off valve
64 sealing material
66 electrode head

Claims

A substrate holding portion for holding the substrate and a counter electrode plate disposed at a position facing the substrate held by the substrate holding portion, wherein an electrolyte is filled between the substrate held by the substrate holding portion and the counter electrode plate. An electrolytic processing unit for performing electrolytic processing while feeding power,
Equipped with multiple electrolyte supply facilities that supply different types of electrolytes,
The electrolytic processing apparatus, wherein the electrolytic processing unit is configured to be selectively connected to one of the plurality of electrolytic solution supply facilities.

2. The electrolytic processing apparatus according to claim 1, further comprising an input device for inputting a signal for arbitrarily selecting the electrolytic solution supply equipment connected to the electrolytic processing unit.

3. The electrolytic processing apparatus according to claim 1, wherein the substrate is a wiring substrate, and the object to be subjected to the electrolytic treatment on the substrate is a metal containing copper.

A transfer device for transferring the substrate,
A substrate holding portion for holding the substrate and a counter electrode plate disposed at a position facing the substrate held by the substrate holding portion, wherein an electrolyte is filled between the substrate held by the substrate holding portion and the counter electrode plate. A plurality of electrolysis processing units that perform electrolysis while feeding power,
Equipped with multiple electrolyte supply facilities that supply different types of electrolytes,
The electrolytic processing apparatus, wherein each of the electrolytic processing units is configured to be selectively connected to any one of the plurality of electrolytic solution supply facilities.

The electrolytic processing apparatus according to claim 4, further comprising an input device for inputting a signal for arbitrarily selecting each of the electrolytic solution supply facilities connected to each of the electrolytic processing units.

The electrolytic processing apparatus according to claim 4, further comprising a cleaning unit for cleaning the substrate.

A first electrolytic treatment is performed by supplying power while filling the first electrolytic solution between the substrate and the counter electrode plate disposed at a position facing the substrate,
An electrolytic treatment method, wherein a second electrolytic treatment is performed by supplying power between a substrate and the counter electrode plate while filling a second electrolytic solution different from the first electrolytic solution.

The electrolytic treatment method according to claim 7, wherein the first electrolytic solution remaining between the substrate and the counter electrode plate is washed and dried between the first electrolytic treatment and the second electrolytic treatment.

9. The electrolytic processing method according to claim 7, wherein the first electrolytic solution and the second electrolytic solution are arbitrary electrolytic solutions selected from a plurality of different types of electrolytic solutions.