JP3703355B2

JP3703355B2 - Board plating equipment

Info

Publication number: JP3703355B2
Application number: JP2000024169A
Authority: JP
Inventors: 保▲広▼ 溝畑; 貞雄平得
Original assignee: Screen Holdings Co Ltd; Dainippon Screen Manufacturing Co Ltd
Current assignee: Screen Holdings Co Ltd; Dainippon Screen Manufacturing Co Ltd
Priority date: 2000-02-01
Filing date: 2000-02-01
Publication date: 2005-10-05
Anticipated expiration: 2020-02-01
Also published as: JP2001217207A

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体ウエハや液晶表示装置用のガラス基板（以下、単に基板と称する）に対してメッキ処理を施す基板メッキ装置に係り、特に硫酸銅などのメッキ液を基板の処理面に供給した状態で給電して電解メッキ処理を行う技術に関する。
【０００２】
【従来の技術】
従来のこの種の装置として、例えば、メッキ液を貯留したチャンバと、基板の処理面を下向きにして基板を保持し、かつ基板をチャンバに対して昇降させる保持機構とを備えたものが挙げられる。
【０００３】
このように構成された装置では、基板の処理面がチャンバのメッキ液に触れる位置にまで基板を下降させた後、チャンバ内のメッキ液を下方から基板の処理面に向けてポンプで上昇させて循環させ、基板の処理面に負電圧を印加するとともにチャンバ内のアノード電極に正電圧を印加する。これにより基板の処理面に対してメッキ処理を施すようになっている。
【０００４】
【発明が解決しようとする課題】
しかしながら、このような構成を有する従来例の場合には、次のような問題がある。
すなわち、基板の処理面に負電圧を印加する電極やマスク部材などを含む保持機構により基板の処理面における周辺部には段差が存在するので、この部分においてメッキ液の流れが妨げられ、チャンバ内を下方から上昇して基板の処理面に達したのちにチャンバの側方に流れだすメッキ液の一部が淀んで滞留する。これにより、この部分において膜厚が薄くなり、基板の面内における膜厚均一性が低下するという問題がある。
【０００５】
また、基板の処理面のうち中央部に向けて下方から上昇されたメッキ液は、処理面に到達すると周辺部に向かって流れてゆくが、中央部から周辺部に向かうにしたがってメッキ液の流れが処理面から離れてゆく。つまり、流路抵抗が大きい処理面の近くよりも、流路抵抗の小さい処理面からやや離れた場所にメッキ液の流れが集まることによる。これによってもやはり上記と同じ問題が生じる。
【０００６】
上記のようにして生じる膜厚の面内均一性を改善するためには、メッキ液の滞留を防止するとともに基板の中央部から周辺部にわたり、処理面に沿ってメッキ液を円滑に流してやる必要がある。そのためには大量のメッキ液をチャンバから供給して循環させる必要が生じ、ポンプ、配管径等の循環系の必要容量が増大し、その結果、メッキ液の循環量が多くなるという別異の問題が生じる。また、その他に、チャンバ内にパンチングプレートを配備して、メッキ液の噴流を適度に分散して基板の処理面全体にわたって均一化する手法もあるが、この場合にはパンチングプレートと基板までの距離を長くとる必要があって装置自体が大型化するという問題が生じてしまう。
【０００７】
さらに、電解メッキを利用してメッキ処理を施す関係上、処理面の全面には予め導電性のシード層が形成されているが、構造上、処理面の周辺部にしかカソード電極が取り付けられないので、中央部は周辺部に比較してシード層の抵抗が大きくなる。そのため中央部は周辺部よりも膜厚が薄くなるといったシード層の抵抗の影響を強く受け易いという問題もある。
【０００８】
本発明は、このような事情に鑑みてなされたものであって、メッキ液の循環量を増やすことなく基板の処理面の全体にわたってメッキ液の円滑な流れを形成することにより、膜厚の面内均一性を高めるとともにメッキ液の節約ができ、しかもシード層の抵抗による影響を小さくすることができる基板メッキ装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明は、このような目的を達成するために、次のような構成をとる。
すなわち、請求項１に記載の発明は、メッキ液を基板の処理面に対して供給することによりメッキ処理を施す基板メッキ装置において、基板の処理面に対して近接し、かつ、処理面側の面が基板の処理面に対してほぼ平行に配設され、流体の流れる方向を三次元的に変えつつ透過させる三次元フィルタを備え、前記三次元フィルタは、メッキ液を貯留するメッキ槽の開口部を閉塞するように配置され、メッキ槽内に配設され、前記三次元フィルタ中におけるメッキ液の電気抵抗をシード層の電気抵抗よりも大きくすることにより、メッキ液に正電圧を印加するアノード電極から、基板の処理面に形成されたシード層に当接し、負電圧を印加するカソード電極までの電圧降下で処理面に形成されているシード層の電気抵抗の大きさによらず電気抵抗を基板面内でほぼ一定とし、前記三次元フィルタを介してメッキ液を供給することを特徴とするものである。
【００１０】
また、請求項２に記載の発明によれば、請求項１に記載の基板メッキ装置において、前記三次元フィルタは、ガラス製またはセラミック製の微粒子を複数個集めて焼成してなることを特徴とするものである。
【００１１】
また、請求項３に記載の発明によれば、請求項１または２に記載の基板メッキ装置において、前記三次元フィルタは、その中央部の厚みが周辺部の厚みに比較して徐々に薄くなるように、基板の処理面とは反対側に位置した側がすり鉢状に形成されていることを特徴とするものである。
【００１２】
また、請求項４に記載の発明によれば、請求項１または２に記載の基板メッキ装置において、前記三次元フィルタは、その中央部に比較的大径の微粒子を用い、その周辺部に比較的小径の微粒子を用いて形成されていることを特徴とするものである。
【００１３】
また、請求項５に記載の発明によれば、請求項１または２に記載の基板メッキ装置において、前記三次元フィルタは、基板の処理面側に比較的小径の微粒子を用い、基板の処理面の反対側に比較的大径の微粒子を用いて多層に形成されていることを特徴とするものである。
【００１４】
また、請求項６に記載の発明によれば、請求項１ないし５のいずれかに記載の基板メッキ装置において、前記三次元フィルタの側面は、メッキ液が流れ出ることを防止する処理が施されていることを特徴とするものである。
【００１５】
また、請求項７に記載の発明によれば、請求項１ないし６のいずれかに記載の基板メッキ装置において、基板の処理面を下向きにして基板を保持する保持手段をさらに備えていることを特徴とするものである。
【００１６】
また、請求項８に記載の発明によれば、請求項７に記載の基板メッキ装置において、前記保持手段を前記三次元フィルタに対して昇降させる昇降手段をさらに備え、前記三次元フィルタの上面にメッキ液を盛った状態で前記保持手段を下降させ、基板の処理面と三次元フィルタの上面とがメッキ液で満たされた状態で基板の処理面にメッキ液を供給することを特徴とするものである。
【００１７】
また、請求項９に記載の発明によれば、請求項１ないし８のいずれかに記載の基板メッキ装置において、前記三次元フィルタは、基板の処理面側の面と基板の処理面との間隔が１０ｍｍ以下となるように配設されていることを特徴とするものである。
【００１８】
【作用】
請求項１に記載の発明の作用は次のとおりである。
流体の流れる方向を三次元的に変えつつ透過させる三次元フィルタが、基板の処理面に近接し、かつ、基板の処理面側の面が処理面に対してほぼ平行に配設され、メッキ液を貯留するメッキ槽の開口部を閉塞するように配置されているので、これを通して供給されたメッキ液は、流路抵抗が小さい基板の処理面と三次元フィルタの基板の処理面側との隙間を通ることになる。したがって、メッキ液はその隙間を通って基板の中央部から周辺部に向かって円滑に流れる。
【００１９】
また、三次元フィルタが介在することにより、その部分におけるメッキ液の抵抗分が大きくなり、シード層のような小さな抵抗分の影響を受けにくくなる。
【００２０】
また、請求項２に記載の発明によれば、ガラス製またはセラミック製の微粒子を複数個集めて焼成することで三次元フィルタを形成できる。
【００２１】
また、請求項３に記載の発明によれば、中央部の厚みが周辺部の厚みに比較して薄くなった「すり鉢」状に三次元フィルタを形成することにより、基板の中央部における電流及びメッキ液の流れを共に増大させることができる。
【００２２】
また、請求項４に記載の発明によれば、中央部に比較的大径の微粒子を、周辺部に比較的小径の微粒子を用いた三次元フィルタとすることで、メッキ液の流れの分布を補正することができる。
【００２３】
また、請求項５に記載の発明によれば、基板側に比較的小径の微粒子を用い、その反対側に比較的大径の微粒子を用いた多層の三次元フィルタとすることで、メッキ液の流れのムラを抑制し、三次元フィルタの流路抵抗を小さくすることができる。
【００２４】
また、請求項６に記載の発明によれば、三次元フィルタの側面からメッキ液が流出することを防止できる。
【００２５】
また、請求項７に記載の発明によれば、保持手段により基板の処理面を下にして基板を保持した状態でメッキ処理を施す。
【００２６】
また、請求項８に記載の発明によれば、三次元フィルタの上面にメッキ液を液盛りした状態で昇降手段により保持手段を下降させるので、基板の処理面が最初にメッキ液に接する。したがって、基板の処理面に気泡が残りにくく、基板の周辺部に気泡が溜まりにくい。
【００２７】
また、請求項９に記載の発明によれば、基板の処理面と、処理面側の三次元フィルタの面との間隔が１０ｍｍ以下であれば、メッキ液を中央部から周辺部に向かって円滑に流すことができる。
【００２８】
【発明の実施の形態】
以下、図面を参照して本発明の一実施例を説明する。
図１は実施例に係る基板メッキ装置の概略構成を示した縦断面図であり、図２は保持機構の一部拡大図である。
【００２９】
基板Ｗは、図示しないシード層が形成された処理面Ｗｓを下方に向けてスピンベース１によって水平姿勢となるように保持されている。このスピンベース１は、板状で環状を呈するマスク部材３と、このマスク部材３の上部に連結された３本（図示の関係上２本だけを示す）の支柱５と、これら３本の支柱５が連結された中空の回転軸７とを備えている。
【００３０】
なお、上記スピンベース１は、本発明における保持手段に相当する。
【００３１】
回転軸７は、図１に示すような高さの処理位置と、この処理位置よりも上方に位置する待機位置とにわたって昇降手段９により昇降駆動される。また、図示しない回転駆動手段によって回転駆動される。
【００３２】
マスク部材３は、その内周側の上部にシール部材１１が装着されている。このシール部材１１は、メッキ液が基板の周縁部に達することを防止するものであり、基板Ｗの処理面Ｗｓのうち周辺部のみに当接するように平面視環状に形成されている。また、処理面Ｗｓのシード層に対して負電圧を印加するためのカソード電極１２が、シール部材１１の外周側から基板Ｗの処理面Ｗｓに向けて延出して配設されている。
【００３３】
スピンベース１の内部には、基板Ｗの裏面周辺部を押圧する押圧部材１３が配備されている。この押圧部材１３は、回転軸７に沿って昇降可能および回転自在に構成されており、スピンベース１内に搬入された基板Ｗをマスク部材３に対して押圧して基板Ｗを挟持する。
【００３４】
スピンベース１の下方には、基板Ｗの直径よりもやや小径のメッキ槽１７（チャンバ）が備えられ、このメッキ槽１７を囲うように回収槽１９が配備されている。メッキ槽１７の底面には開口部２０が形成されており、その周囲には正電圧を印加するためのアノード電極２１が配設されている。このアノード電極２１は、例えば、環状を呈する。回収槽１９からメッキ槽１７の開口部２０には配管２３が連通接続されており、配管２３に取り付けられたポンプ２５によって回収槽１９のメッキ液Ｌがメッキ槽１７の上方に向けて供給されるようになっている。
【００３５】
メッキ槽１７の上部には、その開口部を閉塞するように、三次元フィルタ２７が取り付け具２７ａによって取り付けられている。三次元フィルタ２７の取り付けは、図１の処理位置に基板Ｗが位置した際に、三次元フィルタ２７の上面が基板Ｗの処理面Ｗｓに近接し、かつ、処理面Ｗｓに対して平行となるように行われている。この三次元フィルタ２７は、板状の部材に単に貫通穴を開けたようなものとは異なり、流体の流れる方向を三次元的に変えつつ透過させることにより流れを緩やかにする機能を有する。具体的には、図３に示すように、メッキ液Ｌに耐性を備えたガラス（例えば、石英ガラス）からなる微小径のボール２９を複数個集めて焼成したものである。
【００３６】
なお、本発明における微粒子に相当するボール２９としては、ガラス製だけでなくセラミック製を採用してもよい。また、外形的には、下部の外周面に傾斜面３１を有し、上部の外周面に垂直面３３を有する。これらの傾斜面３１と垂直面３３にはメッキ液Ｌを透さないための処理が施されている。例えば、メッキ液Ｌに対して耐性を有するガラス枠をはめ込んだり、同様に耐性を有する塗布被膜を形成しておけばよい。これにより後述する三次元フィルタ２７の上面へのメッキ液の液盛りを好適に行うことができる。
【００３７】
本実施例における三次元フィルタ２７について、約２００ｍｍ径の基板Ｗを処理する場合について具体的な形状等の数値例を挙げると次のようになる。
すなわち、平均穴径は約２００μｍであり、厚さは１５ｍｍ程度であり、図１に示す処理位置における基板Ｗの処理面Ｗｓと三次元フィルタ２７の上面との間隔ｇは２〜３ｍｍである。なお、この間隔ｇは１０ｍｍ以下であればよい。
【００３８】
上述したようにメッキ槽１７に三次元フィルタ２７を備えているので、本実施例装置におけるシード層の抵抗による影響は次のようになる。
すなわち、図４（ａ）の模式図に示すように、図中に二点鎖線で囲ったメッキ液Ｌを含む基板Ｗの中央部と周辺部における抵抗は、図４（ｂ）に示すようになる。なお、ここでｒ_Sはシード層の抵抗であり、Ｒ_Pは三次元フィルタ２７中におけるメッキ液Ｌの抵抗であり、Ｒ_Lはメッキ液Ｌの抵抗である。また、ｉ_Cは基板Ｗの中心部における電流であり、ｉ_Eは基板Ｗの周辺部における電流であり、Ｖはアノード電極２１からカソードまでの電圧降下を近似的に示している。
【００３９】
三次元フィルタ２７中における固体の体積比を９０％とすると、三次元フィルタ２７中ではメッキ液Ｌの抵抗Ｒ_Pが等価的に三次元フィルタ２７が無い場合の１０倍になったと考えることができる。従来例の場合、基板Ｗの中央部ではシード層の抵抗ｒ_S分だけ周辺部の抵抗よりも大きくなるので、周辺部における電流が少なくなって膜厚が中央部に比較して薄くなるという現象が生じる。しかしながら、本実施例の構成では三次元フィルタ２７が存在していることにより、電流経路全体における抵抗が大きくなってシード層の抵抗ｒ_Sが電流経路全体に及ぼす影響は小さくなる。そのためシード層の抵抗ｒ_Sの影響により膜厚が不均一になる現象が緩和されることになる。
【００４０】
これらを数式的に示すと、
Ｖ＝ｉ_E（Ｒ_L＋Ｒ_P）＝ｉ_C（Ｒ_L＋Ｒ_P＋ｒ_S）
となり、
ｒ_S≪Ｒ_Pであれば、ｉ_E≒ｉ_C
となることからも明らかである。
【００４１】
次に、図５を参照しつつ上述した装置の動作について説明する。
【００４２】
まず、待機位置にあるスピンベース１に対して処理対象である基板Ｗを搬入する（図５（ａ））。基板Ｗは処理面Ｗｓが下向きとされた姿勢であり、その姿勢のまま各支柱５の間を通してマスク部材３上に載置される。次に、押圧部材１３を下降させて基板Ｗを押圧し、基板Ｗの処理面Ｗｓをシール部材１１に密着させるとともに、処理面Ｗｓのシード層にカソード電極１２を当接させる。
【００４３】
さらに、ポンプ２５を作動させて一定量のメッキ液Ｌをメッキ槽１７から押し上げ、三次元フィルタ２７の上面にメッキ液Ｌを液盛りする。
【００４４】
次に、図５（ｂ）のように、昇降手段９によりスピンベース１と押圧部材１３を処理位置まで下降させる。これとともにポンプ２５を作動させ、アノード電極２１とカソード電極１２の間に通電し、図示しない回転駆動手段によりスピンベース１を低速回転させることにより所定時間だけメッキ処理を施す。
【００４５】
所定時間が経過した後は、電極への通電及びポンプ２５を停止するとともに、昇降手段により待機位置まで基板Ｗとともにスピンベース１を上昇させる。そして、スピンベース１を高速回転させて、処理面Ｗｓに付着しているメッキ液Ｌを振り切る。
【００４６】
三次元フィルタ２７を通して供給されたメッキ液Ｌは、流路抵抗が小さい基板Ｗの処理面Ｗｓと三次元フィルタ２７の上面との隙間を通り、流路抵抗が相対的に高い三次元フィルタ２７側に戻ることなく流れることになるので、メッキ液Ｌはその隙間を通って基板Ｗの中央部から周辺部に向かって円滑に流れる。したがって、膜厚の面内均一性を高めることができるとともに、メッキ液Ｌの噴流を強める必要がないのでメッキ液の循環系を小型化でき、その結果、メッキ液Ｌの節約ができる。
【００４７】
また、本実施例装置のように基板Ｗの処理面Ｗｓを下にして基板Ｗを保持した状態でメッキ処理を施すと、構造上どうしても周辺部の隅に気泡が残り易いが、形成された細長い流路を円滑に流れるメッキ液Ｌにより気泡が容易に押し出されて気泡に起因する処理ムラを防止できる。
【００４８】
また、本実施例装置による処理手順のように、液盛りした後に基板Ｗを下降させると、スピンベース１のマスク部材３よりも基板Ｗの処理面Ｗｓが最初にメッキ液に接するので、基板Ｗの処理面Ｗｓに気泡が残りにくく基板Ｗの周辺部に気泡が溜まりにくい。そのため基板Ｗの処理面Ｗｓ全体にメッキ液Ｌをゆきわたらせることができ、基板Ｗの処理面Ｗｓと三次元フィルタ２７の上面との間にメッキ液Ｌが満たされた状態で処理を施すことができるので、メッキ処理をムラなく施すことができる。
【００４９】
本発明は、上述した実施例装置に限定されるものではなく、以下のように種々の変形実施が可能である。
【００５０】
（１）図６に示すように、三次元フィルタ２７Ａを構成してもよい。
すなわち、その中央部の厚みが周辺部の厚みに比較して徐々に薄くなるように、基板Ｗの処理面Ｗｓとは反対側に位置した下面側を『すり鉢状』に形成するようにしてもよい。
【００５１】
このように構成によると、基板Ｗの中央部における電流及びメッキ液Ｌの流れを共に増大させることができるので、中央部の膜厚が周辺部に比較して薄くなった場合に膜厚の面内均一性を高めることができる。
【００５２】
（２）また、図７に示すように、三次元フィルタ２７Ｂを構成してもよい。
すなわち、その中央部には比較的大径のボールを用いたフィルタ２７Ｂ₁を、その周辺部には比較的小径のボールを用いたフィルタ２７Ｂ₂を配置する。
【００５３】
これによると、メッキ液Ｌの流れの分布を補正することができるので、膜厚分布の調整が可能である。さらに、この場合、フィルタ２７Ｂ₁とフィルタ２７Ｂ₂の開口率を変えなければ中央部と周辺部とで電気抵抗がほぼ一定となるので、電流分布を変えずにメッキ液Ｌの液流分布だけを調整することができる。
【００５４】
（３）また、次のように三次元フィルタを構成してもよい。
すなわち、基板Ｗ側に比較的小径のボールを用いた第１層を、その反対側であるメッキ槽側に比較的大径のボールを用いた第２槽を備えた多層の構成とする。
【００５５】
この構成では、メッキ液の流れのムラを抑制し、三次元フィルタの流路抵抗を小さくすることができる。したがって、電流分布も液流分布も変えることなく流れだけを補正して膜厚の分布を調整することができる。
【００５６】
（４）三次元フィルタ２７としては、上述したように微小径のボールを用いるものに限定されるものではなく、繊維などを用いた三次元フィルタ２７であってもよい。
【００５７】
（５）基板Ｗの処理面Ｗｓを上に向け、メッキ液Ｌを上方から供給する基板メッキ装置であっても本発明を適用することができる。
【００５８】
（６）メッキ槽１７内には、従来装置にもあるパンチングプレートを並設して、三次元フィルタ２７に達するメッキ液の流れを均一化するようにしてもよい。
【００５９】
（７）三次元フィルタ２７を微小径のボール２９ではなく、粉状の微粒子で構成してもよく、さらに同じ径でなく種々の径のボール２９や微粒子を焼成して構成するようにしてもよい。
【００６０】
【発明の効果】
以上の説明から明らかなように、請求項１に記載の発明によれば、三次元フィルタを通して供給されたメッキ液は、流路抵抗が小さい、基板の処理面と三次元フィルタのうちの基板の処理面側の面との隙間を通ることになるので、メッキ液はその隙間を通って基板の中央部から周辺部に円滑に流れる。したがって、膜厚の面内均一性を高めることができるとともに、メッキ液の噴流を強める必要がないのでメッキ液の節約ができる。しかも、三次元フィルタによってメッキ液の抵抗分が大きくなるので、シード層の抵抗による影響を受けにくくすることができる。
【００６１】
また、請求項２に記載の発明によれば、ガラス製またはセラミック製の微粒子を複数個集めて焼成することで比較的容易に所望の三次元フィルタを形成することができる。
【００６２】
また、請求項３に記載の発明によれば、中央部の厚みが周辺部の厚みに比較して薄くなった「すり鉢」状に三次元フィルタを形成することにより、基板の中央部における電流及びメッキ液の流れを共に増大させることができるので、中央部の膜厚が周辺部に比較して薄くなった場合に膜厚の面内均一性を高めることができる。
【００６３】
また、請求項４に記載の発明によれば、中央部に比較的大径の微粒子を、周辺部に比較的小径の微粒子を用いた三次元フィルタとすることで、メッキ液の流れの分布を補正することができるので、膜厚分布の調整が可能である。
【００６４】
さらに、この場合、開口率を変えなければ中央部と周辺部とで電気抵抗がほぼ一定であるので、電流分布を変えずにメッキ液の液流分布だけを調整することができる。
【００６５】
また、請求項５に記載の発明によれば、基板側に比較的小径の微粒子を用い、その反対側に比較的大径の微粒子を用いた多層の三次元フィルタとすることにより、メッキ液の流れのムラを抑制し、三次元フィルタの流路抵抗を小さくすることができる。したがって、電流分布も液流分布も変えることなく流れだけを補正して膜厚の分布を調整することができる。
【００６６】
また、請求項６に記載の発明によれば、三次元フィルタの側面からメッキ液が流出することを防止でき、適切に三次元フィルタの上面に液盛りすることができる。
【００６７】
また、請求項７に記載の発明によれば、保持手段により基板の処理面を下にして基板を保持した状態でメッキ処理を施すと、周辺部の隅に気泡が残り易いが、形成された流路を円滑に流れるメッキ液により気泡が容易に押し出され、気泡に起因する処理ムラを防止できる。
【００６８】
また、請求項８に記載の発明によれば、基板の処理面が最初にメッキ液に接するので、基板の処理面に気泡が残りにくく、基板の周辺部に気泡が溜まりにくい。したがって、基板の処理面全体にメッキ液をゆきわたらせることができ、基板の処理面と三次元フィルタの上面との間にメッキ液が満たされた状態で処理を施すことができるので、メッキ処理をムラなく施すことができる。
【００６９】
また、請求項９に記載の発明によれば、基板の処理面と、処理面側の三次元フィルタの面との間隔が１０ｍｍ以下であれば、メッキ液を中央部から周辺部に向かって円滑に流すことができ、メッキ液の円滑な流れを形成できる。
【図面の簡単な説明】
【図１】実施例に係る基板メッキ装置の概略構成を示した縦断面図である。
【図２】保持機構の一部を拡大して示した図である。
【図３】三次元フィルタの説明に供する図である。
【図４】シード層の抵抗による影響を説明する図である。
【図５】メッキ処理時の動作説明に供する図である。
【図６】三次元フィルタの変形例を示した図である。
【図７】三次元フィルタの他の変形例を示した図である。
【符号の説明】
Ｗ … 基板
Ｗｓ … 処理面
Ｌ … メッキ液
１ … スピンベース（保持手段）
３ … マスク部材
５ … 支柱
７ … 回転軸
９ … 昇降手段
１１ … シール部材
１３ … 押圧部材
１７ … メッキ槽（チャンバ）
２３ … 配管
２７ … 三次元フィルタ
２９ … ボール（微粒子）
３１ … 傾斜面
３３ … 垂直面
ｇ … 間隔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate plating apparatus that performs a plating process on a glass substrate (hereinafter simply referred to as a substrate) for a semiconductor wafer or a liquid crystal display device, and in particular, a plating solution such as copper sulfate is supplied to the processing surface of the substrate. The present invention relates to a technique for performing electrolytic plating by supplying power in a state.
[0002]
[Prior art]
As this type of conventional apparatus, for example, a device provided with a chamber in which a plating solution is stored, and a holding mechanism that holds the substrate with the processing surface of the substrate facing down and moves the substrate up and down with respect to the chamber can be cited. .
[0003]
In the apparatus configured as described above, after the substrate is lowered to a position where the processing surface of the substrate comes into contact with the plating solution in the chamber, the plating solution in the chamber is pumped up from below to the processing surface of the substrate. Circulating, applying a negative voltage to the processing surface of the substrate and applying a positive voltage to the anode electrode in the chamber. As a result, a plating process is performed on the processing surface of the substrate.
[0004]
[Problems to be solved by the invention]
However, the conventional example having such a configuration has the following problems.
That is, since there is a step in the peripheral portion of the substrate processing surface by the holding mechanism including an electrode or a mask member that applies a negative voltage to the processing surface of the substrate, the flow of the plating solution is hindered in this portion, and the inside of the chamber A part of the plating solution flowing out to the side of the chamber after rising from below and reaching the processing surface of the substrate stagnates and stays. Accordingly, there is a problem that the film thickness is reduced in this portion, and the film thickness uniformity in the plane of the substrate is lowered.
[0005]
In addition, the plating solution raised from below toward the center of the processing surface of the substrate flows toward the periphery when reaching the processing surface, but the plating solution flows toward the periphery from the center. Goes away from the processing surface. That is, the flow of the plating solution is gathered at a place slightly away from the treatment surface with a small flow resistance rather than near the treatment surface with a high flow resistance. This also causes the same problem as described above.
[0006]
In order to improve the in-plane uniformity of the film thickness generated as described above, it is necessary to prevent the plating solution from staying and to smoothly flow the plating solution along the processing surface from the center to the periphery of the substrate. There is. For this purpose, it is necessary to supply a large amount of plating solution from the chamber and circulate it. This increases the required capacity of the circulation system such as pumps and pipe diameters. As a result, there is another problem that the circulation amount of the plating solution increases. Occurs. In addition, there is another method in which a punching plate is provided in the chamber so that the jet of the plating solution is appropriately dispersed and uniform over the entire processing surface of the substrate. In this case, the distance between the punching plate and the substrate is used. Therefore, there is a problem that the apparatus itself becomes large.
[0007]
Furthermore, a conductive seed layer is formed on the entire processing surface in advance because of the plating process using electrolytic plating, but the cathode electrode can be attached only to the periphery of the processing surface due to the structure. Therefore, the resistance of the seed layer is larger in the central portion than in the peripheral portion. For this reason, there is also a problem that the central portion is easily affected by the resistance of the seed layer, such that the film thickness is thinner than the peripheral portion.
[0008]
The present invention has been made in view of such circumstances, and by forming a smooth flow of the plating solution over the entire processing surface of the substrate without increasing the circulation amount of the plating solution, It is an object of the present invention to provide a substrate plating apparatus that can improve the uniformity inside, save the plating solution, and reduce the influence of the resistance of the seed layer.
[0009]
[Means for Solving the Problems]
In order to achieve such an object, the present invention has the following configuration.
That is, the invention described in claim 1 is a substrate plating apparatus that performs a plating process by supplying a plating solution to the processing surface of the substrate, and is close to the processing surface of the substrate and on the processing surface side. The surface is arranged substantially parallel to the processing surface of the substrate, and includes a three-dimensional filter that transmits the fluid while changing the direction of fluid flow three-dimensionally. The three-dimensional filter is an opening of a plating tank that stores a plating solution. An anode that is disposed so as to close the portion, is disposed in the plating tank, and applies a positive voltage to the plating solution by making the electric resistance of the plating solution in the three-dimensional filter larger than the electric resistance of the seed layer. from the electrode, in contact with the seed layer formed on the treated surface of the substrate, electrical regardless of the magnitude of the electrical resistance of the seed layer formed on the treated surface by the voltage drop to the cathode electrode for applying a negative voltage Anti the substantially constant in the substrate surface, is characterized in supplying the plating solution through the three-dimensional filter.
[0010]
According to a second aspect of the present invention, in the substrate plating apparatus according to the first aspect, the three-dimensional filter is formed by collecting and firing a plurality of glass or ceramic fine particles. To do.
[0011]
According to a third aspect of the present invention, in the substrate plating apparatus according to the first or second aspect, the thickness of the central portion of the three-dimensional filter is gradually reduced as compared with the thickness of the peripheral portion. Thus, the side located on the opposite side of the processing surface of the substrate is formed in a mortar shape.
[0012]
According to a fourth aspect of the present invention, in the substrate plating apparatus according to the first or second aspect, the three-dimensional filter uses a relatively large diameter fine particle at the center portion and is compared with the peripheral portion. It is characterized in that it is formed using fine particles having a small diameter.
[0013]
According to a fifth aspect of the present invention, in the substrate plating apparatus according to the first or second aspect, the three-dimensional filter uses fine particles having a relatively small diameter on the processing surface side of the substrate, and the processing surface of the substrate. It is characterized in that it is formed in a multilayer using relatively large-diameter particles on the opposite side.
[0014]
According to a sixth aspect of the present invention, in the substrate plating apparatus according to any one of the first to fifth aspects, the side surface of the three-dimensional filter is subjected to a treatment for preventing the plating solution from flowing out. It is characterized by being.
[0015]
According to the invention described in claim 7, the substrate plating apparatus according to any one of claims 1 to 6, further comprising holding means for holding the substrate with the processing surface of the substrate facing downward. It is a feature.
[0016]
Further, according to the invention described in claim 8, in the substrate plating apparatus according to claim 7, further comprising elevating means for elevating and lowering the holding means relative to the three-dimensional filter, on the upper surface of the three-dimensional filter. The holding means is lowered in a state where the plating solution is piled up, and the plating solution is supplied to the processing surface of the substrate in a state where the processing surface of the substrate and the upper surface of the three-dimensional filter are filled with the plating solution. It is.
[0017]
According to a ninth aspect of the present invention, in the substrate plating apparatus according to any one of the first to eighth aspects, the three-dimensional filter has an interval between the surface on the processing surface side of the substrate and the processing surface of the substrate. It is arrange | positioned so that it may become 10 mm or less.
[0018]
[Action]
The operation of the first aspect of the invention is as follows.
Three-dimensional filters that transmit while changing the direction of fluid flow in three dimensions is, close to the treated surface of the substrate, and the surface of the treated surface of the substrate is disposed substantially parallel to the processing surface, the plating solution Since the plating solution supplied through this is disposed so as to close the opening of the plating tank for storing the liquid, the gap between the processing surface of the substrate having a low flow resistance and the processing surface side of the substrate of the three-dimensional filter Will go through. Therefore, the plating solution flows smoothly through the gap from the central portion of the substrate toward the peripheral portion.
[0019]
In addition, the presence of the three-dimensional filter increases the resistance of the plating solution at that portion, making it less susceptible to small resistances such as the seed layer.
[0020]
According to the second aspect of the present invention, a three-dimensional filter can be formed by collecting and firing a plurality of glass or ceramic fine particles.
[0021]
Further, according to the invention described in claim 3, by forming the three-dimensional filter in a “mortar” shape in which the thickness of the central portion is thinner than the thickness of the peripheral portion, the current in the central portion of the substrate and Both the flow of plating solution can be increased.
[0022]
According to the invention described in claim 4, the distribution of the flow of the plating solution can be achieved by using a three-dimensional filter that uses relatively large-diameter particles in the central portion and relatively small-diameter particles in the peripheral portion. It can be corrected.
[0023]
Further, according to the invention described in claim 5, by using a multilayer three-dimensional filter using relatively small-diameter particles on the substrate side and relatively large-diameter particles on the opposite side, Flow unevenness can be suppressed, and the flow resistance of the three-dimensional filter can be reduced.
[0024]
Moreover, according to the invention of Claim 6, it can prevent that a plating solution flows out from the side surface of a three-dimensional filter.
[0025]
According to the seventh aspect of the invention, the plating process is performed in a state where the substrate is held by the holding means with the processing surface of the substrate facing down.
[0026]
According to the eighth aspect of the present invention, the holding means is lowered by the elevating means in a state where the plating solution is accumulated on the upper surface of the three-dimensional filter, so that the processing surface of the substrate first comes into contact with the plating solution. Therefore, bubbles are unlikely to remain on the processing surface of the substrate, and bubbles are unlikely to accumulate in the peripheral portion of the substrate.
[0027]
According to the ninth aspect of the present invention, when the distance between the processing surface of the substrate and the surface of the three-dimensional filter on the processing surface side is 10 mm or less, the plating solution is smoothly moved from the central portion toward the peripheral portion. Can be shed.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a schematic configuration of a substrate plating apparatus according to an embodiment, and FIG. 2 is a partially enlarged view of a holding mechanism.
[0029]
The substrate W is held in a horizontal posture by the spin base 1 with the processing surface Ws on which a seed layer (not shown) is formed facing downward. The spin base 1 has a plate-like mask member 3 having an annular shape, three support columns 5 (only two are shown in the illustration) connected to the upper portion of the mask member 3, and the three support columns. And a hollow rotating shaft 7 to which 5 is connected.
[0030]
The spin base 1 corresponds to the holding means in the present invention.
[0031]
The rotary shaft 7 is driven up and down by an elevating means 9 over a processing position having a height as shown in FIG. 1 and a standby position positioned above the processing position. Moreover, it is rotationally driven by a rotational drive means (not shown).
[0032]
The mask member 3 is provided with a seal member 11 on the inner peripheral side. The seal member 11 prevents the plating solution from reaching the peripheral portion of the substrate, and is formed in an annular shape in plan view so as to contact only the peripheral portion of the processing surface Ws of the substrate W. In addition, a cathode electrode 12 for applying a negative voltage to the seed layer on the processing surface Ws is disposed so as to extend from the outer peripheral side of the seal member 11 toward the processing surface Ws of the substrate W.
[0033]
Inside the spin base 1, a pressing member 13 that presses the periphery of the back surface of the substrate W is provided. The pressing member 13 is configured to be movable up and down along the rotating shaft 7 and to be rotatable, and presses the substrate W carried into the spin base 1 against the mask member 3 so as to sandwich the substrate W.
[0034]
Below the spin base 1, a plating tank 17 (chamber) having a diameter slightly smaller than the diameter of the substrate W is provided, and a recovery tank 19 is provided so as to surround the plating tank 17. An opening 20 is formed in the bottom surface of the plating tank 17, and an anode electrode 21 for applying a positive voltage is disposed around the opening 20. For example, the anode electrode 21 has an annular shape. A pipe 23 is connected to the opening 20 of the plating tank 17 from the recovery tank 19, and the plating solution L in the recovery tank 19 is supplied upward of the plating tank 17 by a pump 25 attached to the pipe 23. It is like that.
[0035]
A three-dimensional filter 27 is attached to the upper part of the plating tank 17 with a fixture 27a so as to close the opening. The three-dimensional filter 27 is attached when the substrate W is positioned at the processing position of FIG. 1, the upper surface of the three-dimensional filter 27 is close to the processing surface Ws of the substrate W and parallel to the processing surface Ws. Has been done so. The three-dimensional filter 27 has a function of slowing the flow by changing the direction of fluid flow three-dimensionally, unlike a plate-like member simply having a through hole. Specifically, as shown in FIG. 3, a plurality of micro-sized balls 29 made of glass (for example, quartz glass) resistant to the plating solution L are collected and fired.
[0036]
The balls 29 corresponding to the fine particles in the present invention may be made of ceramic as well as glass. In terms of the outer shape, the lower outer peripheral surface has an inclined surface 31 and the upper outer peripheral surface has a vertical surface 33. The inclined surface 31 and the vertical surface 33 are processed so as not to allow the plating solution L to pass therethrough. For example, a glass frame having resistance to the plating solution L may be fitted, or a coating film having resistance similarly may be formed. Thereby, it is possible to suitably deposit the plating solution on the upper surface of the three-dimensional filter 27 described later.
[0037]
Regarding the three-dimensional filter 27 in the present embodiment, a specific numerical example of the shape or the like in the case of processing a substrate W having a diameter of about 200 mm is as follows.
That is, the average hole diameter is about 200 μm, the thickness is about 15 mm, and the distance g between the processing surface Ws of the substrate W and the upper surface of the three-dimensional filter 27 at the processing position shown in FIG. In addition, this space | interval g should just be 10 mm or less.
[0038]
As described above, since the plating tank 17 includes the three-dimensional filter 27, the influence of the resistance of the seed layer in the apparatus of this embodiment is as follows.
That is, as shown in the schematic diagram of FIG. 4A, the resistance in the central portion and the peripheral portion of the substrate W containing the plating solution L surrounded by the two-dot chain line in the drawing is as shown in FIG. Become. Here, r _S is the resistance of the seed layer, R _P is the resistance of the plating solution L in the three-dimensional filter 27, and R _L is the resistance of the plating solution L. Further, i _C is a current in the central portion of the substrate W, i _E is a current in the peripheral portion of the substrate W, and V approximately indicates a voltage drop from the anode electrode 21 to the cathode.
[0039]
If the volume ratio of the solid in the three-dimensional filter 27 is 90%, it can be considered that the resistance R _P of the plating solution L in the three-dimensional filter 27 is equivalent to 10 times that when the three-dimensional filter 27 is not present. . In the case of the conventional example, the resistance in the central portion of the substrate W is larger than the resistance in the peripheral portion by the resistance r _{S of the} seed layer, so that the current in the peripheral portion is reduced and the film thickness is reduced compared to the central portion. Occurs. However, in the configuration of the present embodiment, the presence of the three-dimensional filter 27 increases the resistance in the entire current path, and the influence of the seed layer resistance r _S on the entire current path is reduced. Therefore, the phenomenon that the film thickness becomes non-uniform under the influence of the resistance r _S of the seed layer is alleviated.
[0040]
Expressing these mathematically,
V = i _E (R _L + R _P ) = i _C (R _L + R _P + r _S )
And
If r _S << R _P , i _E ≒ i _C
It is clear from that.
[0041]
Next, the operation of the above-described apparatus will be described with reference to FIG.
[0042]
First, the substrate W to be processed is carried into the spin base 1 at the standby position (FIG. 5A). The substrate W is in a posture in which the processing surface Ws is directed downward, and is placed on the mask member 3 through the columns 5 while maintaining the posture. Next, the pressing member 13 is lowered to press the substrate W, the processing surface Ws of the substrate W is brought into close contact with the seal member 11, and the cathode electrode 12 is brought into contact with the seed layer of the processing surface Ws.
[0043]
Further, the pump 25 is operated to push up a certain amount of the plating solution L from the plating tank 17, and the plating solution L is deposited on the upper surface of the three-dimensional filter 27.
[0044]
Next, as shown in FIG. 5B, the spin base 1 and the pressing member 13 are lowered to the processing position by the lifting means 9. At the same time, the pump 25 is operated to energize between the anode electrode 21 and the cathode electrode 12, and the spin base 1 is rotated at a low speed by a rotation driving means (not shown), thereby performing plating treatment for a predetermined time.
[0045]
After the predetermined time has elapsed, the energization of the electrodes and the pump 25 are stopped, and the spin base 1 is raised together with the substrate W to the standby position by the elevating means. Then, the spin base 1 is rotated at a high speed to shake off the plating solution L adhering to the processing surface Ws.
[0046]
The plating solution L supplied through the three-dimensional filter 27 passes through the gap between the processing surface Ws of the substrate W having a low flow resistance and the upper surface of the three-dimensional filter 27, and the three-dimensional filter 27 side having a relatively high flow resistance. Therefore, the plating solution L smoothly flows from the central portion of the substrate W toward the peripheral portion through the gap. Therefore, the in-plane uniformity of the film thickness can be improved and the plating liquid circulation system can be reduced in size because it is not necessary to increase the jet of the plating liquid L. As a result, the plating liquid L can be saved.
[0047]
Further, when the plating process is performed while holding the substrate W with the processing surface Ws of the substrate W down as in the apparatus of this embodiment, bubbles tend to remain in the corners of the peripheral portion due to the structure, but the elongated shape formed. Bubbles are easily pushed out by the plating solution L flowing smoothly through the flow path, and processing unevenness caused by the bubbles can be prevented.
[0048]
Further, when the substrate W is lowered after liquid deposition as in the processing procedure by the apparatus of this embodiment, the processing surface Ws of the substrate W first comes into contact with the plating solution rather than the mask member 3 of the spin base 1. Bubbles are unlikely to remain on the processing surface Ws, and bubbles are unlikely to accumulate in the periphery of the substrate W. Therefore, the plating solution L can be spread over the entire processing surface Ws of the substrate W, and the processing is performed in a state where the plating solution L is filled between the processing surface Ws of the substrate W and the upper surface of the three-dimensional filter 27. Therefore, the plating process can be performed evenly.
[0049]
The present invention is not limited to the above-described embodiment apparatus, and various modifications can be made as follows.
[0050]
(1) As shown in FIG. 6, a three-dimensional filter 27A may be configured.
That is, the lower surface side located on the opposite side of the processing surface Ws of the substrate W may be formed in a “mortar shape” so that the thickness of the central portion becomes gradually smaller than the thickness of the peripheral portion. Good.
[0051]
According to such a configuration, both the current in the central portion of the substrate W and the flow of the plating solution L can be increased. Therefore, when the thickness of the central portion becomes thinner than that of the peripheral portion, the film thickness surface The uniformity inside can be improved.
[0052]
(2) Further, as shown in FIG. 7, a three-dimensional filter 27B may be configured.
That is, a filter 27B ₁ using a relatively large-diameter ball is disposed at the center, and a filter 27B ₂ using a relatively small-diameter ball is disposed at the periphery.
[0053]
According to this, since the distribution of the flow of the plating solution L can be corrected, the film thickness distribution can be adjusted. Further, in this case, if the aperture ratios of the filter 27B ₁ and the filter 27B ₂ are not changed, the electric resistance is substantially constant between the central portion and the peripheral portion. Therefore, only the liquid flow distribution of the plating solution L is changed without changing the current distribution. Can be adjusted.
[0054]
(3) Further, in the following manner may be constructed a three-dimensional filter.
That is, a first layer using a relatively small-diameter ball on the substrate W side and a second tank using a relatively large-diameter ball on the opposite side of the plating tank side are formed into a multilayer structure.
[0055]
In this configuration, by suppressing the unevenness of the flow of the plating solution, it is possible to reduce the flow resistance of the three-dimensional filter. Therefore, the film thickness distribution can be adjusted by correcting only the flow without changing the current distribution or the liquid flow distribution.
[0056]
(4) As described above, the three-dimensional filter 27 is not limited to the one using a small-diameter ball, and may be a three-dimensional filter 27 using fibers or the like.
[0057]
(5) The present invention can also be applied to a substrate plating apparatus that supplies the plating solution L from above with the processing surface Ws of the substrate W facing upward.
[0058]
(6) Punching plates that are also present in the conventional apparatus may be arranged in the plating tank 17 so that the flow of the plating solution reaching the three-dimensional filter 27 is made uniform.
[0059]
(7) The three-dimensional filter 27 may be constituted by powdery fine particles instead of the minute diameter balls 29, and may be constituted by firing balls 29 and fine particles having various diameters instead of the same diameter. Good.
[0060]
【The invention's effect】
As is apparent from the above description, according to the first aspect of the present invention, the plating solution supplied through the three-dimensional filter has a low flow path resistance, and the processing surface of the substrate and the substrate of the three-dimensional filter. Since it passes through the gap with the surface on the processing surface side, the plating solution flows smoothly from the central portion of the substrate to the peripheral portion through the gap. Therefore, in-plane uniformity of the film thickness can be improved and the plating solution can be saved because there is no need to increase the jet flow of the plating solution. In addition, since the resistance of the plating solution is increased by the three-dimensional filter, it is difficult to be influenced by the resistance of the seed layer.
[0061]
According to the second aspect of the present invention, a desired three-dimensional filter can be formed relatively easily by collecting and firing a plurality of glass or ceramic fine particles.
[0062]
Further, according to the invention described in claim 3, by forming the three-dimensional filter in a “mortar” shape in which the thickness of the central portion is thinner than the thickness of the peripheral portion, the current in the central portion of the substrate and Since both the flow of the plating solution can be increased, the in-plane uniformity of the film thickness can be enhanced when the film thickness in the central part is thinner than that in the peripheral part.
[0063]
According to the invention described in claim 4, the distribution of the flow of the plating solution can be achieved by using a three-dimensional filter using relatively large-diameter particles in the central portion and relatively small-diameter particles in the peripheral portion. Since the correction can be made, the film thickness distribution can be adjusted.
[0064]
Further, in this case, if the aperture ratio is not changed, the electric resistance is substantially constant between the central portion and the peripheral portion, and therefore, only the liquid flow distribution of the plating solution can be adjusted without changing the current distribution.
[0065]
According to the invention described in claim 5, by using a multilayer three-dimensional filter using relatively small-diameter particles on the substrate side and relatively large-diameter particles on the opposite side, Flow unevenness can be suppressed, and the flow resistance of the three-dimensional filter can be reduced. Therefore, the film thickness distribution can be adjusted by correcting only the flow without changing the current distribution or the liquid flow distribution.
[0066]
Further, according to the invention described in claim 6, it is possible to prevent the plating solution from flowing out from the side surface of the three-dimensional filter, and to appropriately deposit the liquid on the upper surface of the three-dimensional filter.
[0067]
According to the invention of claim 7, when the plating process is performed in a state where the substrate is held with the processing surface of the substrate down by the holding means, bubbles are likely to remain in the corners of the peripheral portion, but formed. Bubbles are easily pushed out by the plating solution flowing smoothly through the flow path, and processing unevenness caused by the bubbles can be prevented.
[0068]
According to the eighth aspect of the present invention, since the processing surface of the substrate first comes into contact with the plating solution, bubbles are unlikely to remain on the processing surface of the substrate, and bubbles are unlikely to accumulate in the peripheral portion of the substrate. Therefore, the plating solution can be spread over the entire processing surface of the substrate, and the processing can be performed with the plating solution filled between the processing surface of the substrate and the upper surface of the three-dimensional filter. Can be applied evenly.
[0069]
According to the ninth aspect of the present invention, when the distance between the processing surface of the substrate and the surface of the three-dimensional filter on the processing surface side is 10 mm or less, the plating solution is smoothly moved from the central portion toward the peripheral portion. And a smooth flow of the plating solution can be formed.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a schematic configuration of a substrate plating apparatus according to an embodiment.
FIG. 2 is an enlarged view of a part of a holding mechanism.
FIG. 3 is a diagram for explaining a three-dimensional filter.
FIG. 4 is a diagram for explaining the influence of the resistance of the seed layer.
FIG. 5 is a diagram for explaining an operation during plating.
FIG. 6 is a diagram showing a modification of the three-dimensional filter.
FIG. 7 is a diagram showing another modification of the three-dimensional filter.
[Explanation of symbols]
W ... Substrate Ws ... Treatment surface L ... Plating solution 1 ... Spin base (holding means)
DESCRIPTION OF SYMBOLS 3 ... Mask member 5 ... Support | pillar 7 ... Rotating shaft 9 ... Elevating means 11 ... Seal member 13 ... Pressing member 17 ... Plating tank (chamber)
23 ... Piping 27 ... Three-dimensional filter 29 ... Ball (fine particles)
31 ... Inclined surface 33 ... Vertical surface g ... Space

Claims

In a substrate plating apparatus that performs a plating process by supplying a plating solution to the processing surface of the substrate,
Provided with a three-dimensional filter that is close to the processing surface of the substrate and whose surface on the processing surface side is disposed substantially parallel to the processing surface of the substrate, and transmits the fluid while changing the direction of fluid flow in three dimensions ,
The three-dimensional filter is disposed so as to close the opening of the plating tank that stores the plating solution, and is disposed in the plating tank .
By making the electric resistance of the plating solution in the three-dimensional filter larger than the electric resistance of the seed layer,
The electrical resistance of the seed layer formed on the processing surface due to the voltage drop from the anode electrode that applies a positive voltage to the plating solution to the seed layer formed on the processing surface of the substrate and to the cathode electrode that applies a negative voltage Regardless of the size of the electrical resistance, the electrical resistance is almost constant in the substrate surface,
A substrate plating apparatus for supplying a plating solution through the three-dimensional filter.

The substrate plating apparatus according to claim 1,
The substrate plating apparatus, wherein the three-dimensional filter is formed by collecting and firing a plurality of glass or ceramic fine particles.

The substrate plating apparatus according to claim 1 or 2,
The three-dimensional filter is characterized in that the side located on the side opposite to the processing surface of the substrate is formed in a mortar shape so that the thickness of the central portion is gradually thinner than the thickness of the peripheral portion. Substrate plating equipment.

The substrate plating apparatus according to claim 1 or 2,
3. The substrate plating apparatus according to claim 3, wherein the three-dimensional filter is formed using relatively large-diameter particles at a central portion thereof and relatively small-diameter particles at a peripheral portion thereof.

The substrate plating apparatus according to claim 1 or 2,
The substrate plating is characterized in that the three-dimensional filter is formed in multiple layers using relatively small-diameter particles on the substrate processing surface side and relatively large-diameter particles on the opposite side of the substrate processing surface. apparatus.

In the board | substrate plating apparatus in any one of Claim 1 thru | or 5,
The substrate plating apparatus, wherein the side surface of the three-dimensional filter is subjected to a treatment for preventing the plating solution from flowing out.

In the board | substrate plating apparatus in any one of Claim 1 thru | or 6,
A substrate plating apparatus, further comprising holding means for holding the substrate with the processing surface of the substrate facing downward.

The substrate plating apparatus according to claim 7,
Elevating means for elevating the holding means relative to the three-dimensional filter;
The holding means is lowered in a state where the plating solution is piled up on the upper surface of the three-dimensional filter, and the plating solution is supplied to the processing surface of the substrate in a state where the processing surface of the substrate and the upper surface of the three-dimensional filter are filled with the plating solution. A substrate plating apparatus characterized by:

In the board | substrate plating apparatus in any one of Claim 1 thru | or 8,
The substrate plating apparatus, wherein the three-dimensional filter is disposed so that a distance between a processing surface side of the substrate and a processing surface of the substrate is 10 mm or less.