JP2004047912A

JP2004047912A - Sucking device and vacuum processing device

Info

Publication number: JP2004047912A
Application number: JP2002206482A
Authority: JP
Inventors: Ken Maehira; 前平　謙; Ko Fuwa; 不破　耕
Original assignee: Ulvac Inc
Current assignee: Ulvac Inc
Priority date: 2002-07-16
Filing date: 2002-07-16
Publication date: 2004-02-12

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sucking device capable of sucking a warped substrate. <P>SOLUTION: The warp of the substrate to be fixed to this sucking device is measured beforehand, and of the front surface and back surface of a supporting body 11, the front surface 12 is formed into a curved shape recessed at a position where the back surface of the substrate is raised and raised inversely at a position where it is recessed so that the back surface of the substrate can be tightly adhered to the front surface 12. The electrodes 15a and 15b of fixed film thickness are arranged on the front surface 12, the film thickness of a protective layer 17 formed on the surface of the electrodes 15a and 15b is also fixed, the three-dimensional shapes of a virtual surface 13 where the surface of the electrodes 15a and 15b is positioned and the virtual surface where the surface of the protective layer 17 is positioned are equal to the front surface 12, and thus the substrate is tightly adhered to the surface of the protective layer 17. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、吸着装置に関し、特に、反りのある基板、または、デバイスを片面に形成することで発生する平面応力によって反りのある基板を吸着する技術を提供する。
【０００２】
【従来の技術】
図１３、図１４の符号１２１は従来技術の吸着装置を示している。この吸着装置１２１は、絶縁材料からなる支持体１２５と、それぞれ複数本の第一、第二の電極１２６、１２７とを有している。
【０００３】
図１３は第一、第二の電極１２６、１２７を説明するための平面図である。
第一、第二の電極１２６、１２７は所定間隔を空けて交互に並べられた状態で支持体１２５表面に配置されている。
【０００４】
第一の電極１２６の一端は、第一の電極１２６に垂直に配置された細長の第一の接続端子１２３にそれぞれ接続されており、結果として、全ての第一の電極１２６は互いに接続されている。同様に、第二の電極１２７も、細長の第二の接続端子１２４によって互いに接続されている。
【０００５】
図１４は図１３のＸ−Ｘ切断線断面図に相当し、支持体１２５の第一、第二の電極１２６、１２７は配置された側の面には絶縁層１３０が形成されており、第一、第二の電極１２６、１２７の表面と、第一、第二の電極１２６、１２７間に位置する支持体１２５の表面は絶縁層１３０に密着している。
【０００６】
この吸着装置１２１に保持対象物を吸着させるには、先ず、吸着装置１２１を真空雰囲気に置き、基板を吸着装置１２１の絶縁層１３０表面に載置する。
第一、第二の電極１２６、１２７はそれぞれ静電チャック電源１２２に接続されており、静電チャック電源１２２を起動し、第一、第二の電極１２６、１２７に対し、それぞれ正負の電圧を印加する。
【０００７】
基板は吸着装置１２１の表面方向に静電力を受け、基板の裏面全面が吸着装置１２１表面に吸着され、結果として基板が吸着装置１２１に固定される。
このような吸着装置１２１は、基板に薄膜、あるいはデバイスを形成する工程で、基板を保持、搬送するために広く用いられている。
ところで、高周波デバイスに代表されるように、デバイスの微小化、軽量化が近年盛んであり、それに伴ない、基板の薄膜化が進んでいる。
【０００８】
基板の反り量は、基板の厚みと面方向の大きさによって異なるが、特に、基板の膜厚が薄い場合、基板の剛性が小さいので、成膜やデバイスの形成の工程の前後で温度変化が生じると、熱応力によって基板が大きく反りかえってしまう。
従来の吸着装置では、反りが生じた基板との密着性が悪く、そのような基板を静電吸着することは困難であった。
【０００９】
【発明が解決しようとする課題】
本発明は上記従来技術の要求に応じるために創作されたものであり、その目的は、膜厚の薄く、反りが生じた基板を確実に吸着可能な吸着装置を提供することにある。
【００１０】
【課題を解決するための手段】
吸着装置の吸着力をｆ、基板と吸着装置との間の距離ｄとした場合の両者の関係は下記式（１）
式（１）……ｆ　１／ｄ^２
で表され、距離が離れると２乗分の１の割合で吸着力が小さくなることを示している。
【００１１】
即ち、基板の反りが大きくなると、基板と吸着装置との間の距離が増大するため、吸着力が小さくなると考えられる。
本発明者等は、基板の反りと吸着力との関係を確認するために、下記に示す条件で「吸着力」の試験を行った。
【００１２】
〔吸着力〕
基板として、最大反り量がそれぞれ異なるシリコンウェハーを複数枚用意した。
真空雰囲気中で、図１３、１４に示すような吸着装置の表面にシリコンウェハーを載置した後、吸着装置に接続された電源を起動し、シリコンウェハーを吸着させた状態で、シリコンウェハーに取り付けたフックを垂直方向に引き上げ、シリコンウェハーが吸着装置から離脱するときの張力をロードセルによって測定した。
【００１３】
尚、各シリコンウェハーの膜厚は１００μｍであり、吸着装置のシリコンウェハーを吸着させる吸着面の平面度は５μｍ以下であった。
測定結果を図１２に示す。図１２の横軸は基板（シリコンウェハー）の最大反り量ｄ（単位：ｍｍ）を示し、縦軸は測定された張力であり、吸着装置が基板を吸着する吸着力（単位：ｋＰａ）を示している。
【００１４】
図１２から明かなように、基板の最大反り量ｄが１ｍｍ以上になると、吸着力が０．０１Ｐａ以下となっている。この吸着装置では、絶縁層の、正負の電圧を印加する第一、第二の電極上の膜厚は無視できる程度に薄く、１ｍｍは、電極と基板との間の最大距離に等しい。
【００１５】
吸着力が０．０１Ｐａ以下では、基板を安定して保持することが不可能であるので、第一、第二の電極の表面から基板までの距離を１ｍｍ以下にすれば、基板の安定して保持することが可能なことがわかる。
また、１ｍｍ以上の反りのある基板を平面矯正することで生ずる内部応力、あるいは、基板の割れを防ぐことからも、電極表面から基板までの距離を１ｍｍ以下に抑えることが必要である。
【００１６】
基板の反り量は、基板の種類、サイズ、厚みやプロセス条件等で変化するので、基板の種類、サイズ、厚みやプロセス条件が同じであれば、基板の反り量が一定である。従って、吸着対象の基板の反りを予め測定し、その反りを有する基板と接触可能なように、吸着装置を形成しておくと、吸着力を強くすることができると予想される。
【００１７】
上記知見に基づいてなされた請求項１記載の発明は、支持体と、前記支持体上を引き回された所定膜厚の電極とを有し、前記電極に電圧を印加し、吸着対象の基板を静電吸着するように構成された吸着装置であって、前記支持体の厚みは、前記基板の反りの形状に応じて異なる大きさに形成され、反りを有する前記基板を該吸着装置上に載置したときに、前記基板と前記吸着装置の表面とが接触し、静電吸着させると、前記基板が前記吸着装置上に密着するように構成された吸着装置である。
尚、支持体の厚みとは、基準となる平面に対して支持体を平行配置したときに、その平面から支持体表面までの距離のことである。
請求項２記載の発明は、平面を有する支持体と、前記平面上を引き回された電極とを有し、前記電極に電圧を印加し、吸着対象の基板を静電吸着するように構成された吸着装置であって、前記電極の膜厚は、前記基板の反りに応じて異なる厚みに形成され、反りを有する前記基板を該吸着装置上に載置したときに、前記基板と前記吸着装置の表面とが接触し、静電吸着させると、前記基板が前記吸着装置上に密着するように構成された吸着装置である。
請求項３記載の発明は、請求項１又は請求項２のいずれか１項記載の吸着装置であって、保護層を有し、前記電極の表面は前記保護層で覆われ、前記電極の表面から、前記保護層表面までの高さが一定に形成された吸着装置である。
請求項４記載の発明は、平面を有する支持体と、前記平面上に引き回された所定膜厚の電極とを有し、前記電極に電圧を印加し、吸着対象の基板を静電吸着するように構成された吸着装置であって、前記電極の表面を覆う保護層を有し、前記保護層の前記電極上の膜厚は、前記基板の反りに応じて異なる厚みに形成され、反りを有する前記基板を該吸着装置上に載置したときに、前記基板と前記吸着装置の表面とが接触し、静電吸着させると、前記基板が前記吸着装置上に密着するように構成された吸着装置である。
請求項５記載の発明は、上下左右に変形可能な支持体と、前記支持体上に設けられた電極とを有する吸着装置である。
請求項６記載の発明は、真空槽と、請求項１乃至請求項５のいずれか１項記載の吸着装置とを有し、前記吸着装置は前記真空槽内に配置され、前記基板は前記真空槽内で前記吸着装置に密着される真空処理装置である。
【００１８】
上記電極を互いに絶縁した正電極と負電極に分け、正電極に正の電圧を印加し、負電極に負の電圧を印加すると、静電吸着力の他グラディエント力も生じうるからシリコン基板のような導電性基板だけではなく、ガラス基板のような絶縁性の基板も密着させることができる。
吸着装置がいずれか一方の極性の電極のみを有する場合は、真空槽が他方の極性の電極とし、吸着装置の電極に正又は負の電圧を印加し、真空槽に負又は正の電圧を印加すれば、静電吸着力を発生させることができる。
【００１９】
吸着装置に、冷却管のような冷却手段やヒータのような加熱手段を内蔵させる、または、吸着装置の近傍に冷却手段や加熱手段を配置しておき、吸着装置を加熱又は冷却すると、熱伝導により基板が加熱又は冷却される。本発明では、基板と吸着装置との密着性が高いので、効率良く基板の加熱又は冷却を行うことができる。
上述した実験結果に従うと、第一、第二の電極の表面から基板までの距離を１ｍｍ以下が望ましく、従って、保護層の電極上の厚みは１ｍｍ以下であることが望ましい。
【００２０】
【発明の実施の形態】
以下で図面を参照し、本発明の実施形態について説明する。
図１の符号１は本発明の一実施形態の真空処理装置であるスパッタリング装置を示しており、図２の符号５はそのスパッタリング装置１で成膜処理される基板を示している。
【００２１】
基板５の表面には、この真空処理装置１で処理する前に、蒸着やスパッタリング等の方法で予め薄膜１９が形成されており、薄膜１９が形成されたときの応力によって、基板５に反りが生じている。
【００２２】
その反りは、例えば、基板５を薄膜１９側から観察した場合に、その中央部分が凹み、逆に、周辺部分がめくれ上がるようになっている。逆に、基板５を裏面、即ち、吸着装置１０に載置される被載置面１８側から観察した場合には、その被載置面１８は中央部分が盛り上がり、周辺部分が凹んだ曲面になっている。
【００２３】
図３の符号１０は、上述した基板５を保持するための本発明第一例の吸着装置を示しており、この吸着装置１０は、支持体１１と、第一、第二の電極１５ａ、１５ｂと、保護層１７とを有している。
支持体１１はセラミックのような柔軟性を有しない絶縁材料、あるいは樹脂のような柔軟性を持った材料が板状に形成されて構成されている。
【００２４】
支持体１１の表面及び裏面のうち、その表面１２は、基板５の被載置面１８と接触可能な形状に形成されている。即ち、支持体１１の表面１２は、被載置面１８を接触させた場合に、基板５の被載置面１８が盛り上がる位置では凹み、凹む位置では逆に盛り上がるような曲面になっている。
【００２５】
第一、第二の電極１５ａ、１５ｂは、支持体１１の表面１２に形成された所定膜厚の銅薄膜がパターニングされて構成されている。ここでは、各電極１５ａ、１５ｂの膜厚は一定になっている。
第一、第二の電極１５ａ、１５ｂは、例えば、図１３に示すように交互に並べられた状態で配置されており、第一、第二の電極１５ａ、１５ｂとの間はそれぞれ所定間隔が空けられ、第一、第二の電極１５ａ、１５ｂは互いに絶縁されている。
【００２６】
保護層１７は二酸化ケイ素（ＳｉＯ_２）のような絶縁材料の薄膜で構成され、各電極１５ａ、１５ｂの表面に一定膜厚で形成されている。ここでは、保護層１７は各電極１５ａ、１５ｂの表面だけを覆うように形成され、電極１５ａ、１５ｂの側面及び、電極１５ａ、１５ｂ間に位置する支持体１１の表面１２はそれぞれ露出している。
【００２７】
図４の符号１３は、各電極１５ａ、１５ｂの表面が位置する仮想的な面を示し、同図の符号１４は各保護層１７表面が位置する仮想的な面を示している。
上述したように、各電極１５ａ、１５ｂの膜厚は一定になっているから、電極１５ａ、１５ｂ表面が位置する仮想的な面１３は、支持体１１の表面１２の立体形状と等しく、また、各保護層１７の膜厚は一定であり、電極１５ａ、１５ｂの表面から保護層１７表面までの高さも一定であるから、各保護層１７の表面が位置する仮想的な面１４は、電極１５ａ、１５ｂが位置する仮想的な面１３の立体形状と等しく、即ち、支持体１１の表面１２の立体形状とも等しくなっている。
【００２８】
各保護層１７の表面が位置する仮想的な面１４を基板の載置面１４とし、該載置面１４の凹んだ部分に、被載置面１８の盛り上がった部分を接触させ、盛り上がった部分に被載置面１８の凹んだ部分を接触させれば、基板５は変形することなく、その被載置面１８が載置面１４に接触した状態で吸着装置１０に載せられる。
【００２９】
支持体１１の裏面は平坦になっており、その裏面を基準面とすると、基準面から支持体１１の表面１２までの高さ、即ち、支持体１１の厚みｗ_１は、表面１２が凹んだ位置では小さく、表面１２が盛り上がった位置では大きくなっている。
即ち、第一例の吸着装置１０では支持体１１を位置に応じて異なる厚みｗ_１に形成し、かつ、その表面１２に一定膜厚の電極１５ａ、１５ｂと、一定膜厚の保護層１７を形成することで、吸着装置１０の載置面１４は、基板の反りに対応する形状になっている。
【００３０】
真空処理装置１は真空槽２と、上述した吸着装置１０とを有している。真空槽２内の底壁側には台９が配置されており、台９の表面は平坦な水平面になっている。吸着装置１０は、支持体１１の裏面が、台９の表面に密着するよう配置されているから、吸着装置１０は水平になっている。
【００３１】
真空槽２内の天井側にはターゲット３が水平配置されており、真空層２に接続された真空排気系８によって真空槽２内に真空雰囲気を形成した後、該真空雰囲気を維持した状態で、真空槽２内に基板５を搬入し、該基板５を吸着装置１０の載置面１４に載せると、基板５は水平配置され、ターゲット３と対向する。
【００３２】
この基板５はシリコン基板のような導電性基板で構成されており、第一、第二の電極１５ａ、１５ｂに接続された静電チャック電源７を起動し、第一、第二の電極１５ａ、１５ｂに正負の電圧を印加すると、静電吸着力によって基板５が吸着装置１０に吸着され、基板５の被載置面１８が吸着装置１０に強く密着する。
【００３３】
吸着装置１０の支持体１１内部には、加熱手段であるヒータが設けられており、予めヒータによって吸着装置１０が所定温度に昇温しているので、基板５は熱伝導によって昇温する。この吸着装置１０には、不図示のセンサーが取り付けられており、このセンサーが基板５の温度を測定し、ヒータの通電量を制御することで、基板５が温度制御される。
【００３４】
ターゲット３は真空槽２外に配置されたスパッタ電源６に接続されており、真空槽２内にアルゴンガス（Ａｒ）のようなスパッタガスを所定量導入しながら、真空槽２内の真空雰囲気を維持し、その状態でスパッタ電源６を起動し、ターゲット３に直流電圧を印加すると、ターゲット３がスパッタされ、温度制御された状態の基板５の表面に薄膜が成長する。
【００３５】
その薄膜が所定膜厚まで成長したところで、スパッタリングを停止して、成膜工程を終了する。静電チャック電源７を停止させると、基板５への吸着力が解除され、成膜後の基板５を吸着装置１０から持ち上げることができる。
【００３６】
以上は、保護層１７を電極１５ａ、１５ｂ表面のみに配置する場合について説明したが、本発明はこれに限定されるものではない。
図５の符号２０は、第一例の吸着装置の保護層に代え、第一、第二の電極２５ａ、２５ｂの表面及び側面と、第一、第二の電極２５ａ、２５ｂ間に位置する支持体２１表面とを覆う保護層を有する吸着装置を示しており、この吸着装置２０の支持体２１と、第一、第二の電極２５ａ、２５ｂは第一例の吸着装置１０と同じである。
【００３７】
保護層２７も、第一例の吸着装置と同様に、電極２５ａ、２５ｂ上の膜厚は一定になっているので、保護層２７表面に上述した基板を接触させることができる。
更に、保護層を有さない吸着装置も本発明に含まれる。
【００３８】
図６の符号３０は、第一例の吸着装置１０の保護層を形成しない状態の吸着装置を示している。保護層を有する場合は、基板が電極と直接接触しないため、導電性基板を直接吸着装置に載せることが可能であったが、この吸着装置３０は電極３５ａ、３５ｂ表面が直接基板に接触するため、少なくとも、基板の被載置面が絶縁性である必要がある。
【００３９】
以上は、支持体１１の厚みを位置によって変え、かつ、一定膜厚の電極１５ａ、１５ｂを形成する場合について説明したが、本発明はこれに限定されるものではない。
図７の符号４０は本発明第二例の吸着装置を示している。この吸着装置４０は支持体４１と、第一、第二の電極４５ａ、４５ｂと、保護層４７とを有している。
【００４０】
支持体４１は柔軟性を有しない絶縁性材料が、厚みが一定な板状に形成されて構成されており、その表面及び裏面は平坦になっている。
第一、第二の電極４５ａ、４５ｂは支持体４１の同じ面に配置されている。
【００４１】
上述したような反りが生じた基板５をこの吸着装置４０に載せる場合、各電極４５ａ、４５ｂは被載置面１８の盛り上がった部分が対応する位置では厚みｗ_２が小さく、被載置面１８の凹んだ部分が対応する位置ではｗ_２が大きくなっており、仮に、保護層４７が形成されていないとすると、全ての電極４５ａ、４５ｂ表面が被載置面１８に接触するようになっている。
【００４２】
保護層４７は各電極４５ａ、４５ｂ表面のみに形成されており、各保護層４７の膜厚は一定になっているので、保護層４７の表面に基板５を載せると、全ての保護層４７の表面が基板５の被載置面１８に接触する。
【００４３】
第一、第二の電極４５ａ、４５ｂはそれぞれ複数本あり、第一、第二の電極４５ａ、４５ｂは交互にならべられているので、各保護層４７表面を被載置面１８に接触させた状態で、第一、第二の電極４５ａ、４５ｂに正負の電圧を印加すると、基板５が吸着装置４０に強く密着される。
【００４４】
以上は、保護層４７を電極４５ａ、４５ｂ表面のみに配置する場合について説明したが、本発明はこれに限定されるものではなく、図８の符号５０に示す吸着装置のように、第二例の吸着装置の保護層に代え、第一、第二の電極５５ａ、５５ｂの表面及び側面と、第一、第二の電極５５ａ、５５ｂ間に位置する支持体５１表面とを覆う保護層５７を形成しても良い。
【００４５】
この保護層５７は、図５に示した吸着装置２０と同様に、電極５５ａ、５５ｂ上の膜厚が一定になっているので、保護層５７表面に上述した基板を接触させることができる。
【００４６】
更に、保護層を有しない吸着装置も本発明に含まれる。図９の符号６０は、第二例の吸着装置４０の保護層を形成しない状態の吸着装置を示しており、この吸着装置６０は第二例の吸着装置４０と同様の支持体６１と第一、第二の電極６５ａ、６５ｂとで構成されている。
この吸着装置６０は、図６に示した吸着装置３０と同様に、電極６５ａ、６５ｂ表面が直接基板に接触するため、少なくとも、基板の被載置面が絶縁性である必要がある。
【００４７】
以上は、電極の厚み又は支持体の厚みのいずれか一方を基板の反りに対応するように位置毎に変化させる場合について説明したが、本発明はこれに限定されるものではない。
図１０の符号７０は本発明第三例の吸着装置を示している。この吸着装置７０は、支持体７１と、第一、第二の電極７５ａ、７５ｂと、保護層７７とを有している。
【００４８】
支持体７１は柔軟性を有しない絶縁性材料が、厚みが一定な板状に形成されて構成されており、その表面及び裏面は平坦になっている。
第一、第二の電極７５ａ、７５ｂは所定膜厚に形成され、支持体７１の同じ面にそれぞれ配置されている。ここでは、各電極７５ａ、７５ｂは一定膜厚になっている。保護層７７は、少なくとも第一、第二の電極７５ａ、７５ｂの表面を覆うように配置されている。
【００４９】
ここでは、保護層７７は第一、第二の電極７５ａ、７５ｂの表面及び側面と、第一、第二の電極７５ａ、７５ｂ間に位置する支持体７１表面とを覆うように形成されている。
上述したような反りが生じた基板５をこの保護層７７表面に載せる場合、電極７５ａ、７５ｂの厚みと、保護層７７の電極７５ａ、７５ｂ上の厚みｗ_３の合計は、基板５の被載置面１８が盛り上がった位置では小さく、被載置面１８が凹んだ位置では大きくなっている。
【００５０】
支持体７１表面から保護層４７の表面までの高さは、第一、第二の電極７５ａ、７５ｂ間の位置では、電極７５ａ、７５ｂ上の位置と同じ高さ、又は、それよりも低くなっているので、基板５を保護層４７表面に乗せたときに、基板５の被載置面１８が電極７５ａ、７５ｂ上の位置で保護層４７の表面と接触するようになっている。
【００５１】
第一、第二の電極７５ａ、７５ｂはそれぞれ複数本あり、互いに交互に並べられているので、基板５の被載置面１８を保護層７７表面に接触させた状態で、第一、第二の電極７５ａ、７５ｂに正負の電圧を印加すると、基板５がこの吸着装置７０に強く密着される。
【００５２】
以上は、保護層７７が、電極７５ａ、７５ｂの表面及び側面と、電極７５ａ、７５ｂ間の支持体７１表面とを覆う場合について説明したが、本発明はこれに限定されるものではなく、第三例の吸着装置７０の保護層７７に代え、保護層を各電極の表面のみを覆うように形成しても良い。
【００５３】
以上は、支持体を柔軟性を有しない絶縁材料で構成する場合について説明したが、本発明はこれに限定されるものではない。
図１１（ａ）の符号９５は本発明の一実施形態の搬送装置を示している。
この搬送装置９５は吸着装置８０と、移動手段９６とを有している。
【００５４】
吸着装置８０は、支持体８６と、第一、第二の電極８５ａ、８５ｂと、保護層８７とを有している。
第一、第二の電極８５ａ、８５ｂは支持体８６表面にそれぞれ配置され、保護層８７は、少なくとも各電極８５ａ、８５ｂの表面を覆うように形成されている。ここでは、保護層８７は、各電極８５ａ、８５ｂの表面及び側面と、第一、第二の電極８５ａ、８５ｂ間に位置する支持体８６の表面を覆うように形成されている。
【００５５】
支持体８６と保護層８７は樹脂やゴムのような柔軟性を有する絶縁材料がシート状に形成されて構成され、また、第一、第二の電極８５ａ、８５ｂは、支持体８６及び保護層８７の変形を妨げない程度に膜厚の薄い銅薄膜のような金属薄膜で構成されている。従って、支持体８６と保護層８７とで構成される積層体８１は変形可能になっている。
【００５６】
移動手段９６は棒状の支持手段８９を複数本有している、吸着装置８０は保護層８７が配置された面が下側に向けられ、支持体８６の表面が上側に向けられており、支持体８６表面に各支持手段８９の下端がそれぞれ取りつけられている。
【００５７】
支持手段８９の上端は、移動手段９６の不図示の移動機構に接続されており、移動機構によって各支持手段８９を同じ方向に移動させると、吸着装置８０は支持手段８９と共に移動するようになっている。
図１１（ａ）の符号９０はエッチングや成膜等の処理によって反りが生じた基板を示している。
【００５８】
各支持手段８９は支持体８６を含む吸着装置８０が変形する動きに追従して水平方向と垂直方向に移動可能になっているので、支持手段８９と共に吸着装置８０を基板９０上方に配置し、支持手段８９を下降させて吸着装置８０を基板９０上に載せると、吸着装置８０は支持手段８９に妨げられることなく変形し、吸着装置８０が基板９０の表面、即ち、保護層８７の表面が基板９０の被載置面９２に接触する。
【００５９】
吸着装置８０が被載置面９２に接触したところで、各支持手段８９を吸着装置８０に対して相対的に固定すると、吸着装置８０も固定される。第一、第二の電極８５ａ、８５ｂは不図示の電源に接続されており、この電源を起動し、第一、第二の電極８５ａ、８５ｂにそれぞれ正負の電圧を印加すると、基板９０が吸着装置８０に強く密着される。
【００６０】
その状態で、各支持手段８９を上方に移動すると、基板９０が吸着装置８０に密着された状態で持ち上げられ、次いで、各支持手段８９を同じ方向に水平移動させると、吸着装置８０と共に基板９０も搬送される。
【００６１】
以上は、第一、第二の電極８５ａ、８５ｂが保護層８７に覆われた場合について説明したが、本発明はこれに限定されるものではなく、例えば、柔軟性を有する絶縁膜からなる支持体の表面に、第一、第二の電極を形成し、第一、第二の電極を支持体表面で露出させてもよい。
【００６２】
以上は、第一、第二の電極を銅薄膜で構成する場合について説明したが、本発明はこれに限定されず、アルミニウム等他の金属の薄膜で構成しても良いし、更に、金属に限定されるものでもなく、カーボンなどの導電性材料で構成しても良い。
【００６３】
また、本発明の吸着装置を備えた真空処理装置として、スパッタリング装置について説明したが、本発明はこれに限られるものではなく、例えばＣＶＤ装置等の成膜装置や、あるいはエッチング装置、搬送機構等に本発明の吸着装置を用いることもできる。
【００６４】
また、本発明の吸着装置に吸着される基板の種類も特に限定されるものではなく、基板としては、ガラス基板、樹脂製のフィルム基板等の絶縁性基板、あるいは、シリコン基板等の導電性基板も吸着可能である。
【００６５】
【発明の効果】
反りが生じた基板を静電吸着する際に、吸着力を大きくできる。
【図面の簡単な説明】
【図１】本発明の一実施形態の吸着装置を備えた真空処理装置の構成を説明する図
【図２】本発明の吸着装置に吸着される基板を説明する断面図
【図３】本発明の吸着装置の第一例を説明する断面図
【図４】電極及び保護層の表面と、支持体表面との関係を説明するための図
【図５】本発明の第一例の吸着装置の変形例を説明する断面図
【図６】本発明の第一例の吸着装置の他の変形例を説明する断面図
【図７】本発明の吸着装置の第二例を説明する断面図
【図８】本発明の第二例の吸着装置の変形例を説明する断面図
【図９】本発明の第二例の吸着装置の他の変形例を説明する断面図
【図１０】本発明の吸着装置の第三例を説明する断面図
【図１１】（ａ）、（ｂ）：本発明の搬送装置の一例を、その搬送工程と共に説明する工程図
【図１２】基板の反り量と吸着力との関係を説明するグラフ
【図１３】従来の吸着装置を説明する平面図
【図１４】従来の吸着装置を説明する断面図
【符号の説明】
１……スパッタリング装置（真空処理装置）　　５……基板　　１０……吸着装置　　１１……支持体　　２５ａ、２５ｂ……電極　　１７……保護層　　支持体の厚み……Ｗ_１ [0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a suction device, and more particularly to a technique for suctioning a warped substrate or a warped substrate due to plane stress generated by forming a device on one side.
[0002]
[Prior art]
Reference numeral 121 in FIGS. 13 and 14 denotes a conventional suction device. The suction device 121 has a support 125 made of an insulating material and a plurality of first and second electrodes 126 and 127, respectively.
[0003]
FIG. 13 is a plan view for explaining the first and second electrodes 126 and 127. FIG.
The first and second electrodes 126 and 127 are arranged on the surface of the support 125 in a state of being alternately arranged at predetermined intervals.
[0004]
One end of the first electrode 126 is connected to an elongated first connection terminal 123 arranged vertically to the first electrode 126, and as a result, all the first electrodes 126 are connected to each other. I have. Similarly, the second electrodes 127 are connected to each other by the elongated second connection terminals 124.
[0005]
FIG. 14 corresponds to a cross-sectional view taken along line XX of FIG. 13, in which an insulating layer 130 is formed on a surface of the support 125 on which the first and second electrodes 126 and 127 are arranged. The surfaces of the first and second electrodes 126 and 127 and the surface of the support 125 located between the first and second electrodes 126 and 127 are in close contact with the insulating layer 130.
[0006]
In order to cause the suction device 121 to adsorb the object to be held, first, the suction device 121 is placed in a vacuum atmosphere, and the substrate is placed on the surface of the insulating layer 130 of the suction device 121.
The first and second electrodes 126 and 127 are connected to the electrostatic chuck power supply 122, respectively, and activate the electrostatic chuck power supply 122 to apply positive and negative voltages to the first and second electrodes 126 and 127, respectively. Apply.
[0007]
The substrate receives an electrostatic force in the direction of the surface of the suction device 121, and the entire back surface of the substrate is suctioned to the surface of the suction device 121, and as a result, the substrate is fixed to the suction device 121.
Such a suction device 121 is widely used for holding and transporting a substrate in a process of forming a thin film or a device on the substrate.
By the way, as typified by high-frequency devices, miniaturization and weight reduction of devices have been actively pursued in recent years, and accordingly, the thickness of substrates has been reduced.
[0008]
The amount of warpage of the substrate varies depending on the thickness of the substrate and the size in the plane direction. Particularly, when the thickness of the substrate is small, the rigidity of the substrate is small, so that the temperature change before and after the film formation and device formation steps. If this occurs, the substrate will warp significantly due to thermal stress.
In a conventional suction device, adhesion to a warped substrate is poor, and it has been difficult to electrostatically suction such a substrate.
[0009]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made to meet the above-mentioned demands of the related art, and an object of the present invention is to provide a suction device capable of reliably sucking a substrate having a small thickness and a warp.
[0010]
[Means for Solving the Problems]
When the suction force of the suction device is f and the distance d between the substrate and the suction device is d, the relationship between the two is as follows:
Formula (1): f 1 / d²
It indicates that when the distance increases, the suction force decreases by a factor of 1/2.
[0011]
That is, it is considered that when the warpage of the substrate increases, the distance between the substrate and the suction device increases, so that the suction force decreases.
The present inventors conducted a test of “adsorption power” under the following conditions in order to confirm the relationship between substrate warpage and adsorption power.
[0012]
(Adsorption power)
A plurality of silicon wafers having different maximum warpages were prepared as substrates.
After placing the silicon wafer on the surface of the suction device as shown in FIGS. 13 and 14 in a vacuum atmosphere, start the power supply connected to the suction device and attach the silicon wafer to the silicon wafer in a state where the silicon wafer is sucked. The hook was pulled up in the vertical direction, and the tension when the silicon wafer was detached from the suction device was measured by a load cell.
[0013]
The thickness of each silicon wafer was 100 μm, and the flatness of the suction surface of the suction device for suctioning the silicon wafer was 5 μm or less.
FIG. 12 shows the measurement results. The horizontal axis in FIG. 12 indicates the maximum warp d (unit: mm) of the substrate (silicon wafer), and the vertical axis indicates the measured tension, which indicates the suction force (unit: kPa) at which the suction device suctions the substrate. ing.
[0014]
As is clear from FIG. 12, when the maximum warp d of the substrate is 1 mm or more, the suction force is 0.01 Pa or less. In this adsorption device, the thickness of the insulating layer on the first and second electrodes to which positive and negative voltages are applied is so small that it can be ignored, and 1 mm is equal to the maximum distance between the electrode and the substrate.
[0015]
If the suction force is 0.01 Pa or less, it is impossible to stably hold the substrate. Therefore, if the distance from the surface of the first and second electrodes to the substrate is 1 mm or less, the substrate can be stably held. It can be seen that it can be held.
Further, in order to prevent internal stress caused by flattening a substrate having a warp of 1 mm or more or cracking of the substrate, it is necessary to suppress the distance from the electrode surface to the substrate to 1 mm or less.
[0016]
The amount of warpage of the substrate varies depending on the type, size, thickness, process conditions, and the like of the substrate. Therefore, if the type, size, thickness, and process conditions of the substrate are the same, the amount of warpage of the substrate is constant. Therefore, it is expected that if the warpage of the substrate to be suctioned is measured in advance and the suction device is formed so as to be able to come into contact with the warped substrate, the suction force can be increased.
[0017]
The invention according to claim 1, which has been made based on the above-mentioned knowledge, has a support, and an electrode having a predetermined film thickness routed on the support, and applies a voltage to the electrode to form a substrate to be adsorbed. Wherein the thickness of the support is formed in different sizes according to the shape of the warpage of the substrate, and the substrate having the warp is placed on the suction device. The suction device is configured such that when the substrate is placed, the substrate comes into contact with the surface of the suction device, and the substrate is brought into close contact with the suction device when electrostatically attracted.
In addition, the thickness of the support means the distance from the plane to the surface of the support when the support is arranged parallel to a reference plane.
The invention according to claim 2 has a support having a flat surface, and an electrode routed on the flat surface, and is configured to apply a voltage to the electrode and electrostatically attract a substrate to be attracted. Wherein the film thickness of the electrode is formed to have a different thickness in accordance with the warpage of the substrate, and when the warped substrate is placed on the suction device, the substrate and the suction device are disposed. The substrate is a suction device configured to be brought into contact with the surface of the device and electrostatically attracted to cause the substrate to come into close contact with the suction device.
According to a third aspect of the present invention, there is provided the adsorption device according to any one of the first and second aspects, further comprising a protective layer, wherein a surface of the electrode is covered with the protective layer, and a surface of the electrode is provided. And the height from the surface to the surface of the protective layer is constant.
According to a fourth aspect of the present invention, there is provided a support having a flat surface, and an electrode having a predetermined thickness routed on the flat surface, and a voltage is applied to the electrode to electrostatically attract a substrate to be attracted. It is a suction device configured as described above, having a protective layer covering the surface of the electrode, the film thickness of the protective layer on the electrode is formed to a different thickness according to the warpage of the substrate, the warpage When the substrate having the substrate is placed on the suction device, the substrate is brought into contact with the surface of the suction device, and when the substrate is electrostatically suctioned, the suction is configured such that the substrate comes into close contact with the suction device. Device.
According to a fifth aspect of the present invention, there is provided an adsorption apparatus having a support which can be deformed vertically and horizontally, and an electrode provided on the support.
The invention according to claim 6 has a vacuum chamber and the suction device according to any one of claims 1 to 5, wherein the suction apparatus is disposed in the vacuum chamber, and the substrate is a vacuum chamber. This is a vacuum processing device that is closely attached to the suction device in a tank.
[0018]
If the above electrode is divided into a positive electrode and a negative electrode that are insulated from each other, and a positive voltage is applied to the positive electrode and a negative voltage is applied to the negative electrode, a gradient force can be generated in addition to the electrostatic attraction force, such as a silicon substrate Not only a conductive substrate but also an insulating substrate such as a glass substrate can be adhered.
When the suction device has only one polarity electrode, the vacuum chamber is the other polarity electrode, and a positive or negative voltage is applied to the suction device electrode, and a negative or positive voltage is applied to the vacuum chamber. Then, an electrostatic attraction force can be generated.
[0019]
In the adsorption device, a cooling device such as a cooling pipe or a heating device such as a heater is built in, or a cooling device or a heating device is arranged in the vicinity of the adsorption device. Heats or cools the substrate. In the present invention, since the adhesion between the substrate and the suction device is high, the substrate can be efficiently heated or cooled.
According to the above experimental results, the distance from the surface of the first and second electrodes to the substrate is desirably 1 mm or less, and therefore, the thickness of the protective layer on the electrode is desirably 1 mm or less.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Reference numeral 1 in FIG. 1 indicates a sputtering apparatus which is a vacuum processing apparatus according to an embodiment of the present invention, and reference numeral 5 in FIG. 2 indicates a substrate on which a film is formed by the sputtering apparatus 1.
[0021]
Before processing by the vacuum processing apparatus 1, a thin film 19 is formed on the surface of the substrate 5 by a method such as evaporation or sputtering, and the substrate 5 is warped by the stress generated when the thin film 19 is formed. Has occurred.
[0022]
The warp is such that, for example, when the substrate 5 is observed from the thin film 19 side, the central portion is depressed, and conversely, the peripheral portion is turned up. Conversely, when the substrate 5 is observed from the back surface, that is, from the mounting surface 18 side on which the suction device 10 is mounted, the mounting surface 18 has a curved surface in which the central portion rises and the peripheral portion is concave. Has become.
[0023]
Reference numeral 10 in FIG. 3 indicates a suction device according to a first example of the present invention for holding the substrate 5 described above. The suction device 10 includes a support 11 and first and second electrodes 15a and 15b. And a protective layer 17.
The support body 11 is formed by forming a flexible insulating material such as ceramic or a flexible material such as resin into a plate shape.
[0024]
Of the front and back surfaces of the support 11, the front surface 12 is formed in a shape that can contact the mounting surface 18 of the substrate 5. That is, the surface 12 of the support 11 has a curved surface such that when the mounting surface 18 is brought into contact with the mounting surface 18, the mounting surface 18 of the substrate 5 is concave when the mounting surface 18 is raised, and conversely when the mounting surface 18 is recessed.
[0025]
The first and second electrodes 15 a and 15 b are configured by patterning a copper thin film having a predetermined thickness formed on the surface 12 of the support 11. Here, the film thickness of each of the electrodes 15a and 15b is constant.
For example, the first and second electrodes 15a and 15b are arranged in a state of being alternately arranged as shown in FIG. 13, and a predetermined interval is provided between the first and second electrodes 15a and 15b, respectively. The first and second electrodes 15a and 15b are insulated from each other.
[0026]
The protective layer 17 is made of silicon dioxide (SiO₂), And is formed with a constant thickness on the surface of each of the electrodes 15a and 15b. Here, the protective layer 17 is formed so as to cover only the surfaces of the electrodes 15a and 15b, and the side surfaces of the electrodes 15a and 15b and the surface 12 of the support 11 located between the electrodes 15a and 15b are exposed. .
[0027]
Reference numeral 13 in FIG. 4 indicates a virtual surface where the surface of each of the electrodes 15a and 15b is located, and reference numeral 14 in FIG. 4 indicates a virtual surface where the surface of each protective layer 17 is located.
As described above, since the thickness of each of the electrodes 15a and 15b is constant, the virtual surface 13 where the surfaces of the electrodes 15a and 15b are located is equal to the three-dimensional shape of the surface 12 of the support 11, and Since the thickness of each protective layer 17 is constant and the height from the surfaces of the electrodes 15a and 15b to the surface of the protective layer 17 is also constant, the virtual surface 14 where the surface of each protective layer 17 is located is , 15b are equal to the three-dimensional shape of the virtual surface 13 where the support 11 is located, ie, the three-dimensional shape of the surface 12 of the support 11 is also equal.
[0028]
The imaginary surface 14 on which the surface of each protective layer 17 is located is the mounting surface 14 of the substrate, and the raised portion of the mounting surface 18 is brought into contact with the recessed portion of the mounting surface 14, and the raised portion When the recessed portion of the mounting surface 18 is brought into contact with the substrate 5, the substrate 5 is placed on the suction device 10 while the mounting surface 18 is in contact with the mounting surface 14 without being deformed.
[0029]
The back surface of the support 11 is flat, and when the back surface is used as a reference surface, the height from the reference surface to the front surface 12 of the support 11, that is, the thickness w of the support 11.₁Is small at the position where the surface 12 is concave, and is large at the position where the surface 12 is raised.
That is, in the suction device 10 of the first example, the support 11 is provided with different thicknesses w depending on the position.₁By forming electrodes 15a and 15b having a constant thickness and a protective layer 17 having a constant thickness on the surface 12, the mounting surface 14 of the suction device 10 has a shape corresponding to the warpage of the substrate. It has become.
[0030]
The vacuum processing device 1 has a vacuum tank 2 and the above-described adsorption device 10. A table 9 is arranged on the bottom wall side in the vacuum chamber 2, and the surface of the table 9 is a flat horizontal surface. Since the suction device 10 is arranged such that the back surface of the support 11 is in close contact with the surface of the base 9, the suction device 10 is horizontal.
[0031]
A target 3 is horizontally arranged on the ceiling side in the vacuum chamber 2, and after a vacuum atmosphere is formed in the vacuum chamber 2 by a vacuum exhaust system 8 connected to the vacuum layer 2, the vacuum atmosphere is maintained. When the substrate 5 is carried into the vacuum chamber 2 and the substrate 5 is mounted on the mounting surface 14 of the suction device 10, the substrate 5 is horizontally disposed and faces the target 3.
[0032]
The substrate 5 is formed of a conductive substrate such as a silicon substrate, and activates the electrostatic chuck power supply 7 connected to the first and second electrodes 15a and 15b, and starts the first and second electrodes 15a and 15b. When a positive or negative voltage is applied to 15b, the substrate 5 is attracted to the attraction device 10 by the electrostatic attraction force, and the mounting surface 18 of the substrate 5 is strongly adhered to the attraction device 10.
[0033]
A heater serving as a heating means is provided inside the support 11 of the suction device 10, and the substrate 5 is heated by heat conduction because the temperature of the suction device 10 is previously raised to a predetermined temperature by the heater. A sensor (not shown) is attached to the suction device 10, and the sensor measures the temperature of the substrate 5 and controls the amount of current supplied to the heater, whereby the temperature of the substrate 5 is controlled.
[0034]
The target 3 is connected to a sputtering power source 6 arranged outside the vacuum chamber 2, and a vacuum atmosphere in the vacuum chamber 2 is introduced while a predetermined amount of a sputtering gas such as argon gas (Ar) is introduced into the vacuum chamber 2. If the DC voltage is applied to the target 3 by activating the sputtering power source 6 in this state, the target 3 is sputtered and a thin film grows on the surface of the substrate 5 in a temperature-controlled state.
[0035]
When the thin film has grown to a predetermined thickness, the sputtering is stopped and the film forming process is completed. When the electrostatic chuck power supply 7 is stopped, the suction force on the substrate 5 is released, and the substrate 5 after film formation can be lifted from the suction device 10.
[0036]
Although the case where the protective layer 17 is disposed only on the surfaces of the electrodes 15a and 15b has been described above, the present invention is not limited to this.
Reference numeral 20 in FIG. 5 denotes a support positioned between the surfaces and side surfaces of the first and second electrodes 25a and 25b and the first and second electrodes 25a and 25b instead of the protective layer of the suction device of the first example. This shows an adsorption device having a protective layer covering the surface of the body 21. The support 21 of the adsorption device 20 and the first and second electrodes 25a and 25b are the same as those of the adsorption device 10 of the first example.
[0037]
The protective layer 27 also has a constant film thickness on the electrodes 25a and 25b as in the suction device of the first example, so that the above-described substrate can be brought into contact with the surface of the protective layer 27.
Further, the present invention includes an adsorption device having no protective layer.
[0038]
Reference numeral 30 in FIG. 6 indicates the suction device in the state where the protective layer of the suction device 10 of the first example is not formed. When the protective layer is provided, the conductive substrate can be directly placed on the suction device because the substrate does not directly come into contact with the electrodes. However, this suction device 30 is used because the surfaces of the electrodes 35a and 35b directly contact the substrate. At least, the mounting surface of the substrate needs to be insulative.
[0039]
The case where the thickness of the support 11 is changed depending on the position and the electrodes 15a and 15b having a constant thickness are formed has been described above, but the present invention is not limited to this.
Reference numeral 40 in FIG. 7 indicates a suction device according to the second embodiment of the present invention. The suction device 40 has a support 41, first and second electrodes 45a and 45b, and a protective layer 47.
[0040]
The support body 41 is formed by forming an insulative material having no flexibility in a plate shape having a constant thickness, and the front and back surfaces thereof are flat.
The first and second electrodes 45a and 45b are arranged on the same surface of the support 41.
[0041]
When the warped substrate 5 is placed on the suction device 40, the electrodes 45a and 45b have thicknesses w at positions where the raised portions of the placement surface 18 correspond.₂Is small, and w is at a position corresponding to the concave portion of the placement surface 18.₂If the protective layer 47 is not formed, the surfaces of all the electrodes 45a and 45b come into contact with the mounting surface 18.
[0042]
Since the protective layer 47 is formed only on the surface of each of the electrodes 45a and 45b, and the thickness of each protective layer 47 is constant, when the substrate 5 is placed on the surface of the protective layer 47, The surface contacts the mounting surface 18 of the substrate 5.
[0043]
Since there are a plurality of first and second electrodes 45a and 45b, and the first and second electrodes 45a and 45b are alternately arranged, the surface of each protective layer 47 is brought into contact with the mounting surface 18. When positive and negative voltages are applied to the first and second electrodes 45a and 45b in this state, the substrate 5 is strongly adhered to the suction device 40.
[0044]
The case where the protective layer 47 is disposed only on the surface of the electrodes 45a and 45b has been described above. However, the present invention is not limited to this, and the second example, such as the adsorption device indicated by reference numeral 50 in FIG. Of the first and second electrodes 55a and 55b, and the surface of the support body 51 located between the first and second electrodes 55a and 55b. It may be formed.
[0045]
Since the protective layer 57 has a uniform film thickness on the electrodes 55a and 55b, similarly to the suction device 20 shown in FIG. 5, the above-described substrate can be brought into contact with the surface of the protective layer 57.
[0046]
Further, the present invention includes an adsorption device having no protective layer. Reference numeral 60 in FIG. 9 denotes an adsorption device in a state where the protective layer of the adsorption device 40 of the second example is not formed, and the adsorption device 60 has a support 61 and a first member similar to the adsorption device 40 of the second example. , Second electrodes 65a and 65b.
In the suction device 60, as in the case of the suction device 30 shown in FIG. 6, since the surfaces of the electrodes 65a and 65b are in direct contact with the substrate, it is necessary that at least the mounting surface of the substrate is insulative.
[0047]
The case where one of the thickness of the electrode and the thickness of the support is changed for each position so as to correspond to the warpage of the substrate has been described above, but the present invention is not limited to this.
Reference numeral 70 in FIG. 10 indicates a suction device according to a third embodiment of the present invention. This adsorption device 70 has a support 71, first and second electrodes 75 a and 75 b, and a protective layer 77.
[0048]
The support 71 is made of an insulative material having no flexibility and is formed in a plate shape having a constant thickness, and its front and rear surfaces are flat.
The first and second electrodes 75a and 75b are formed to have a predetermined thickness and are arranged on the same surface of the support 71, respectively. Here, each of the electrodes 75a and 75b has a constant film thickness. The protective layer 77 is disposed so as to cover at least the surfaces of the first and second electrodes 75a and 75b.
[0049]
Here, the protective layer 77 is formed so as to cover the surfaces and side surfaces of the first and second electrodes 75a and 75b and the surface of the support 71 located between the first and second electrodes 75a and 75b. .
When the substrate 5 having the warp as described above is placed on the surface of the protective layer 77, the thickness of the electrodes 75a and 75b and the thickness w of the protective layer 77 on the electrodes 75a and 75b₃Is small at the position where the mounting surface 18 of the substrate 5 is raised, and is large at the position where the mounting surface 18 is concave.
[0050]
The height from the surface of the support 71 to the surface of the protective layer 47 is the same height as the position on the electrodes 75a and 75b or lower at the position between the first and second electrodes 75a and 75b. Therefore, when the substrate 5 is placed on the surface of the protective layer 47, the mounting surface 18 of the substrate 5 comes into contact with the surface of the protective layer 47 at a position on the electrodes 75a and 75b.
[0051]
Since the first and second electrodes 75a and 75b are plural in number and are arranged alternately with each other, the first and second electrodes 75a and 75b are arranged in a state where the mounting surface 18 of the substrate 5 is in contact with the surface of the protective layer 77. When positive and negative voltages are applied to the electrodes 75a and 75b, the substrate 5 is strongly adhered to the suction device 70.
[0052]
Although the case where the protective layer 77 covers the surfaces and side surfaces of the electrodes 75a and 75b and the surface of the support 71 between the electrodes 75a and 75b has been described above, the present invention is not limited to this. Instead of the protective layer 77 of the three suction devices 70, the protective layer may be formed so as to cover only the surface of each electrode.
[0053]
The case where the support is made of an insulating material having no flexibility has been described above, but the present invention is not limited to this.
Reference numeral 95 in FIG. 11A indicates a transport device according to an embodiment of the present invention.
The transfer device 95 has a suction device 80 and a moving unit 96.
[0054]
The suction device 80 has a support 86, first and second electrodes 85a and 85b, and a protective layer 87.
The first and second electrodes 85a and 85b are respectively disposed on the surface of the support 86, and the protective layer 87 is formed so as to cover at least the surface of each of the electrodes 85a and 85b. Here, the protective layer 87 is formed so as to cover the surfaces and side surfaces of the electrodes 85a and 85b and the surface of the support 86 located between the first and second electrodes 85a and 85b.
[0055]
The support 86 and the protective layer 87 are formed by forming a flexible insulating material such as resin or rubber into a sheet shape, and the first and second electrodes 85a and 85b are formed of the support 86 and the protective layer. 87 is made of a metal thin film such as a copper thin film having a thickness small enough not to hinder deformation. Therefore, the laminate 81 including the support 86 and the protective layer 87 is deformable.
[0056]
The moving means 96 has a plurality of rod-shaped support means 89, and the suction device 80 has a surface on which the protective layer 87 is disposed facing downward, and a surface of the support 86 facing upward. The lower end of each support means 89 is attached to the surface of the body 86.
[0057]
The upper end of the supporting means 89 is connected to a moving mechanism (not shown) of the moving means 96. When each supporting means 89 is moved in the same direction by the moving mechanism, the suction device 80 moves together with the supporting means 89. ing.
Reference numeral 90 in FIG. 11A indicates a substrate on which warpage has occurred due to processing such as etching or film formation.
[0058]
Since each support means 89 is movable in the horizontal and vertical directions following the deformation of the suction device 80 including the support 86, the suction device 80 is arranged together with the support means 89 above the substrate 90, When the support device 89 is lowered and the suction device 80 is placed on the substrate 90, the suction device 80 is deformed without being hindered by the support device 89, and the suction device 80 is turned on the surface of the substrate 90, that is, the surface of the protective layer 87. It comes into contact with the mounting surface 92 of the substrate 90.
[0059]
When the support device 89 is fixed relative to the suction device 80 when the suction device 80 comes into contact with the mounting surface 92, the suction device 80 is also fixed. The first and second electrodes 85a and 85b are connected to a power supply (not shown). When the power supply is started and positive and negative voltages are applied to the first and second electrodes 85a and 85b, the substrate 90 is attracted. It is strongly adhered to the device 80.
[0060]
In this state, when each supporting means 89 is moved upward, the substrate 90 is lifted in a state in which the substrate 90 is in close contact with the suction device 80. Next, when each supporting means 89 is horizontally moved in the same direction, Is also transported.
[0061]
The case where the first and second electrodes 85a and 85b are covered with the protective layer 87 has been described above. However, the present invention is not limited to this. For example, a support made of a flexible insulating film may be used. First and second electrodes may be formed on the surface of the body, and the first and second electrodes may be exposed on the surface of the support.
[0062]
In the above, the case where the first and second electrodes are formed of a copper thin film has been described. However, the present invention is not limited to this, and may be formed of a thin film of another metal such as aluminum. It is not limited, and may be made of a conductive material such as carbon.
[0063]
Also, a sputtering apparatus has been described as a vacuum processing apparatus provided with the adsorption apparatus of the present invention. However, the present invention is not limited to this. For example, a film forming apparatus such as a CVD apparatus, an etching apparatus, a transport mechanism, and the like. The adsorption device of the present invention can also be used.
[0064]
The type of the substrate to be adsorbed by the adsorption device of the present invention is not particularly limited, and the substrate may be an insulating substrate such as a glass substrate, a resin film substrate, or a conductive substrate such as a silicon substrate. Can also be adsorbed.
[0065]
【The invention's effect】
When electrostatically attracting the warped substrate, the attraction force can be increased.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a vacuum processing apparatus including an adsorption device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view illustrating a substrate sucked by the suction device of the present invention.
FIG. 3 is a cross-sectional view illustrating a first example of the suction device of the present invention.
FIG. 4 is a diagram for explaining the relationship between the surface of an electrode and a protective layer and the surface of a support.
FIG. 5 is a cross-sectional view illustrating a modification of the suction device according to the first embodiment of the present invention.
FIG. 6 is a cross-sectional view illustrating another modification of the suction device of the first example of the present invention.
FIG. 7 is a cross-sectional view illustrating a second example of the suction device of the present invention.
FIG. 8 is a cross-sectional view illustrating a modified example of the suction device of the second example of the present invention.
FIG. 9 is a cross-sectional view illustrating another modified example of the suction device of the second example of the present invention.
FIG. 10 is a sectional view illustrating a third example of the suction device of the present invention.
FIGS. 11A and 11B are process diagrams illustrating an example of the transfer device of the present invention together with the transfer process.
FIG. 12 is a graph illustrating the relationship between the amount of substrate warpage and the attraction force.
FIG. 13 is a plan view illustrating a conventional suction device.
FIG. 14 is a cross-sectional view illustrating a conventional suction device.
[Explanation of symbols]
1 ... sputtering apparatus (vacuum processing apparatus) 5 ... substrate 10 ... adsorption apparatus 11 ... supports 25a and 25b ... electrodes 17 ... protective layer / thickness of support W₁

Claims

A suction device, comprising: a support, an electrode having a predetermined thickness drawn around the support, and applying a voltage to the electrode to electrostatically suction a substrate to be suctioned. ,
The thickness of the support is formed in different sizes depending on the shape of the warpage of the substrate,
When the substrate having the warp is placed on the suction device, the substrate comes into contact with the surface of the suction device, and when electrostatically adsorbed, the substrate is configured to be in close contact with the suction device. Adsorption equipment.

A suction device configured to have a support having a flat surface and an electrode routed on the flat surface, apply a voltage to the electrode, and electrostatically suction a substrate to be suctioned,
The thickness of the electrode is formed to a different thickness according to the warpage of the substrate,
When the substrate having the warp is placed on the suction device, the substrate comes into contact with the surface of the suction device, and when electrostatically adsorbed, the substrate is configured to be in close contact with the suction device. Adsorption equipment.

3. The device according to claim 1, further comprising a protective layer, wherein a surface of the electrode is covered with the protective layer, and a height from the surface of the electrode to the surface of the protective layer is formed to be constant. The adsorption device according to the above.

A suction device configured to have a support having a flat surface and an electrode of a predetermined thickness routed on the flat surface, apply a voltage to the electrode, and electrostatically suction a substrate to be suctioned. So,
Having a protective layer covering the surface of the electrode,
The thickness of the protective layer on the electrode is formed to a different thickness according to the warpage of the substrate,
When the substrate having the warp is placed on the suction device, the substrate comes into contact with the surface of the suction device, and when electrostatically adsorbed, the substrate is configured to be in close contact with the suction device. Adsorption equipment.

An adsorption device having a support that can be deformed up, down, left, and right, and an electrode provided on the support.

A vacuum tank, and the suction device according to any one of claims 1 to 5, wherein the suction device is disposed in the vacuum tank, and the substrate is in close contact with the suction device in the vacuum tank. Vacuum processing equipment.