JP3847581B2 - Plasma processing apparatus and plasma processing system - Google Patents

Description

ここで、
δ：表皮深さ
ω：高周波電源から供給される高周波周波数
μ：透磁率（＝μ₀ 真空の透磁率）
σ：低抵抗部材の導電率
である。
【００３２】
また、本発明においては、前記高周波電力配電体および／または前記接続体の表面が、絶縁体からなる絶縁被膜によって覆われてなることにより、高周波電力配電体および／または接続体において酸化等の経時変化することを防止でき、配電体部分における高周波抵抗の変動を抑制することが可能となり、高周波電力配電体および／または接続体に生じる高周波特性の経時変化に起因するプラズマ処理の変動要因を抑制し、再現性が高く安定したプラズマ処理をおこなうことができ、特に、複数回のプラズマ処理をおこなう際においても、それぞれのプラズマ処理結果を安定させることができる。
【００３３】
また、本発明において前記高周波電力配電体および／または前記接続体が剛体からなることにより、プラズマ処理進行に伴うプラズマ処理装置の経時変化によっても発生する可能性があるプラズマ処理のばらつき、特に、高周波電力配電体および／または接続体に生じる変形によりこの部分の高周波特性が変化することに起因するプラズマ処理経時変化の変動要因を抑制し、時間的に均一で安定したプラズマ処理をおこなうことができ、特に、複数回のプラズマ処理をおこなう際、回を重ねるごとに、それぞれのプラズマ処理結果を安定させることができる。
ここで、「剛体」とは、高周波電力配電体および／または接続体がプラズマ処理中に変形しないこと、つまり、「作動中に高周波特性が変化しない」を意味し、さらに、取り外しおよび組み立てを伴う「メンテナンス前後で変形しない」「取り付け時における取り付け位置の再現性を有する」ことを意味している。これにより、プラズマ処理前に設定した高周波特性をプラズマ処理後、そして分解再組み立てを有するその後のメンテナンス後にも維持することができるため、再現性の高いプラズマ処理を安定しておこなうことが可能となる。
【００３４】
さらに、前記高周波電力配電体および／または前記接続体が、前記プラズマ処理室のチャンバ壁に接続される遮蔽導体内部に収容されてなることにより、整合回路の設置場所の自由度を損なうことなく、配電体部分において高周波電力の伝播する部分空間におけるエネルギー密度をより減少し、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限をいっそう低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスをより低減することができ、その結果、プラズマ発生空間で消費される実効的な高周波電力をさらに増大することが可能となる。
また、外部への不要輻射を遮断できる。
ここで、遮蔽導体は、整合回路がその内部に収容されているマッチングボックスおよびこのマッチングボックスに接続されるシャーシから構成されるとともに、この整合回路とプラズマ励起電極が設けられるチャンバとが離れた位置に設置された場合には、遮蔽導体にはマッチングボックス，シャーシおよびこのシャーシとチャンバとを結んで配電体部分を収容するハウジングの部分を含むものである。これにより整合回路と電極とチャンバとの位置関係に関わりなく、給電部分の遮蔽をおこなうことが可能となる。
ここで、マッチングボックスは、例えば高周波電源からの同軸ケーブルとされる電源線の外導体に接続されて接地電位となっており、かつ、シャーシまたはハウジングは、チャンバ壁およびマッチングボックスに接続されており、これら、チャンバ壁、ハウジング、シャーシ、マッチングボックス、外導体、はそれぞれ、高周波電源から供給された高周波電流が電源側に戻る経路、つまり、電流経路の復路を構成しているものである。
【００３５】
本発明のプラズマ処理装置においては、上述の各プラズマ処理装置において、前記プラズマ処理室ユニットが複数設けられてなることにより、複数のプラズマチャンバ（プラズマ処理室ユニット）に対して、配電体部分の高周波抵抗等の電気的高周波的な特性の機差を低減することが可能となり、個々のプラズマチャンバにおいて、プラズマ空間で消費される実効的な電力の差を低減することができる。
その結果、複数のプラズマチャンバに対して同一のプロセスレシピを適用して、プラズマ処理結果のばらつきを低減すること、つまり、複数のプラズマチャンバにおいて例えば成膜をおこなった際に、膜厚、絶縁耐圧、エッチングレート等、の膜特性の差が生じることを防止できる。
【００３６】
本発明のプラズマ処理システムにおいては、上述の各プラズマ処理装置が複数設けられてなる手段を採用することにより、上記のプラズマ処理装置と同様の効果を奏することのできるプラズマ処理システムを提供することが可能となる。
【００３７】
【発明の実施の形態】
以下、本発明に係るプラズマ処理装置およびプラズマ処理システムの第１実施形態を、図面に基づいて説明する。
［第１実施形態］
図１は本実施の形態のプラズマ処理装置７１の概略構成を示す図である。本実施の形態のプラズマ処理装置７１は、例えば、トップゲート型ＴＦＴの半導体能動膜をなす多結晶シリコンの成膜からゲート絶縁膜の成膜までの一貫処理が可能なものとされ、複数の処理室ユニットを有する装置とされる。
【００３８】
本実施の形態のプラズマ処理装置７１は、図１に示すように、略七角形状の搬送室７２の周囲に、５つの処理室ユニットと１つのローダ室７３と１つのアンローダ室７４とが連設されている。また、５つの処理室ユニットの内訳としては、アモルファスシリコン膜を成膜する第１成膜室、シリコン酸化膜を成膜する第２成膜室、およびシリコン窒化膜を成膜する第３成膜室からなるプラズマ処理室ユニット（プラズマチャンバ）７５，７６，７７、成膜後の被処理基板のアニーリング処理を行うレーザアニール室７８、成膜後の被処理基板の熱処理を行う熱処理室７９、である。
【００３９】
プラズマ処理室ユニット（プラズマチャンバ）である、第１成膜室７５、第２成膜室７６、第３成膜室７７はそれぞれ異なる種類の膜を成膜するような異なる処理をおこなうことも可能であり、また、同一のプロセスレシピにより同一の処理をおこなうこともできるものであるが、略同一の構成とされている。そして、これらの複数のプラズマチャンバ７５，７６，７７においては、後述するように、配電体部分３において、高周波電力配電体３１，３２ａが複数本からなるとともに、高周波電力配電体３１，３２ａが接続板（接続体）Ｃ３１によって互いに接続され前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１から前記電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定された構成とされている。
ここでは第１成膜室７５を例に挙げてその構成を説明する。
【００４０】
図２は本実施形態のプラズマ処理室ユニット（プラズマチャンバ）の概略構成を示す断面図、図３は図２におけるプラズマ処理室ユニット（プラズマチャンバ）の配電体部分３を示す斜視図、図４は図２の配電体部分３およびプラズマ励起電極４を示す平面図である。
【００４１】
プラズマチャンバ（第１成膜室）７５は、ＣＶＤ（ chemical vapor deposition）、スパッタリング、ドライエッチング、アッシング等のプラズマ処理が可能な１周波数励起タイプのプラズマ処理室ユニットとされ、図２に示すように、プラズマを励起するための平行平板型電極４，８が設けられ、この電極４に配電体部分３を介して接続された高周波電源１と、前記プラズマチャンバ７５と前記高周波電源１とのインピーダンス整合を得るための整合回路２Ａとを具備する構成とされる。
【００４２】
さらに詳細に説明すると、プラズマチャンバ７５には、図２，図３に示すように、チャンバ室（プラズマ処理室）６０の上部位置に高周波電源１に接続されたプラズマ励起電極（電極）４およびシャワープレート５が設けられ、チャンバ室６０の下部にはシャワープレート５に対向して被処理基板１６を載置するサセプタ電極（対向電極）８が設けられている。プラズマ励起電極４は、配電体部分３および整合回路２Ａを介して第１の高周波電源１と接続されている。これらプラズマ励起電極４および配電体部分３は、シャーシ２１に覆われるとともに、整合回路２Ａは導電体からなるマッチングボックス２の内部に収納されている。これらシャーシ（遮蔽導体）２１、マッチングボックス（遮蔽導体）２は互いに接続されるとともに、後述するように、マッチングボックス２は同軸ケーブルとされる給電線１Ａのシールド線（外導体）に接続されている。
【００４３】
プラズマ励起電極（カソード電極）４は、このプラズマ励起電極４面方向の断面が円形とされるプラズマ室６０に対応して、その輪郭形状が直径３０ｃｍ程度の円形とされている。また、プラズマ励起電極（電極）４の下側には環状の凸部４ａが設けられるとともに、このプラズマ励起電極（カソード電極）４の下には、多数の孔７が形成されているシャワープレート５が凸部４ａに接して設けられている。これらプラズマ励起電極４とシャワープレート５との間には空間６が形成されている。この空間６にはシャーシ２１の側壁を貫通するとともにプラズマ励起電極（カソード電極）４を貫通してガス導入管１７が接続されている。
【００４４】
このガス導入管１７は、導体からなるとともに、ガス導入管１７の途中には絶縁体１７ａがシャーシ２１内側位置に介挿されてプラズマ励起電極４側とガス供給源側とが絶縁される。
ガス導入管１７から導入されたガスは、シャワープレート５の多数の孔７，７からチャンバ壁１０により形成されたチャンバ室６０内に供給される。チャンバ壁１０とプラズマ励起電極（カソード電極）４とは絶縁体９により互いに絶縁されている。また、図２において、チャンバ室６０に接続されるべき排気系の図示は省略してある。
一方、チャンバ室６０内には基板１６を載置しプラズマ励起電極ともなる盤状のウエハサセプタ（サセプタ電極）８が設けられている。
【００４５】
サセプタ電極（対向電極）８の下部中央には、シャフト１３が接続され、このシャフト１３がチャンバ底部１０Ａを貫通して設けられるとともに、シャフト１３の下端部とチャンバ底部１０Ａ中心部とがベローズ１１により密閉接続されている。これら、ウエハサセプタ８およびシャフト１３はベローズ１１により上下動可能となっており、プラズマ励起電極４，８間の距離の調整ができる。
これらサセプタ電極８とシャフト１３とが接続されているため、サセプタ電極８，シャフト１３，ベローズ１１，チャンバ底部１０Ａ，チャンバ壁１０は直流的に同電位となっている。さらに、チャンバ壁１０とシャーシ２１は接続されているため、チャンバ壁１０，シャーシ２１，マッチングボックス２はいずれも直流的に同電位となっている。
【００４６】
ここで、整合回路２Ａは、チャンバ室６０内のプラズマ状態等の変化に対応してインピーダンスを調整するために、その多くは複数の受動素子を具備する構成とされている。具体的には、整合回路２Ａは、図２に示すように、複数の受動素子として、高周波電源１と給電板３との間に設けられ、インダクタンスコイル２３と、エアバリコンからなるチューニングコンデンサ２４と、真空バリコンからなるロードコンデンサ２２と、から構成されている。
これらのうち、インダクタンスコイル２３，チューニングコンデンサ２４は、整合回路２Ａの入力端子側から出力端子ＰＲ側へ直列に接続されるとともに、インダクタンスコイル２３の間の分岐点からこれらと並列にロードコンデンサ２２が接続されている。このインダクタンスコイル２３，チューニングコンデンサ２４は、導体を介さずに直接接続されており、また、ロードコンデンサ２２の一端は、導体を介してマッチングボックス（接地電位部分）２に接続されている。
ここで、チューニングコンデンサ２４は整合回路２Ａの受動素子のうち最終端とされ、このチューニングコンデンサ２４の出力端子は整合回路２Ａの出力端子ＰＲとされており、チューニングコンデンサ２４は配電体部分（高周波電力配電体）３を介してプラズマ励起電極４に接続されている。
【００４７】
マッチングボックス２は、同軸ケーブルとされる給電線（高周波電力給電体）１Ａのシールド線に接続されており、このシールド線が直流的にアースされている。これにより、サセプタ電極８，シャフト１３，ベローズ１１，チャンバ底部１０Ａ，チャンバ壁１０，シャーシ２１，マッチングボックス２は接地電位に設定されることになり、同時に、ロードコンデンサ２２の一端も直流的にアースされた状態となる。
【００４８】
出力端子ＰＲとプラズマ励起電極４とに接続されている配電体部分３としては、図３に示すように、いずれも断面円形状で径寸法２〜１０ｍｍ、長さ寸法１００〜３００ｍｍの等しい形状を有する棒状の銅からなる剛体の高周波電力配電体３１，３２ａが接続板（接続体）Ｃ３１によって互いに接続されてなるものが用いられており、この高周波電力配電体３１の一端は、整合回路２Ａの出力端子ＰＲとされるチューニングコンデンサ２４の出力端子にネジ止めなどの結合手段により着脱可能に取り付けられており、高周波電力配電体３１の他端は接続板（接続体）Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）に直交して接続されている。
【００４９】
接続板Ｃ３１は、輪郭形状がプラズマ励起電極４より小さく、このプラズマ励起電極４と相似状態の直径２０ｃｍ程度の円形状の板状体とされて、例えば、厚さ２ｍｍ程度からなる剛体の銅板とされている。この接続板Ｃ３１は、その裏側面がプラズマ励起電極４と平行状態に対向してプラズマ励起電極４と整合回路２Ａの出力端子ＰＲとの間に設けられている。
ここで、接続板Ｃ３１がプラズマ励起電極４と相似状態となるとは、電流伝播経路に沿った方向（ｉ軸方向）から見た接続板Ｃ３１の輪郭形状がそれぞれ相似になるということを意味している。
【００５０】
接続板（接続体）Ｃ３１の裏側面（プラズマ励起電極４側面）には複数の高周波電力配電体３２ａがその一端で接続された状態で垂設され、これら高周波電力配電体３２ａの他端がプラズマ励起電極４表面に直交して接続されている。つまり、プラズマ励起電極４と直交する方向とされる出力端子ＰＲからプラズマ励起電極４までの電流の伝播方向とされるｉ軸と平行に高周波電力配電体３２ａは設けられている。
【００５１】
本実施形態の高周波電力配電体３１，３２ａにおいて、前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１からプラズマ励起電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定されてなる。言い換えると、チューニングコンデンサ２４の出力端子ＰＲに取り付けられた一本の高周波電力配電体３１の一端から、プラズマ励起電極４表面に接続された複数本の高周波電力配電体３２ａの他端にむかって、高周波電力配電体３１，３２ａにおける高周波電流の伝播する空間が広がり、実質的に高周波抵抗が減少し、かつインダクタンスが低減されるようになっている。
具体的には、出力端子ＰＲ側は、一本の高周波電力配電体３１とされ、プラズマ励起電極４側は、３本の高周波電力配電体３２ａとされて、高周波電流の伝播する空間としては、約３倍になっている。
【００５２】
ここで、例えば３本とされる複数の高周波電力配電体３２ａは、互いに平行状態とされて、かつ、円形のプラズマ励起電極４の中心４０に対して軸対称な状態でプラズマ励起電極４に接続されている。ここで、軸対称とは、電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌに対して空間的に対称なこと、つまり、それぞれの高周波電力配電体３２ａは、図４に示すように、正三角形Ｔの頂点に位置し、この正三角形Ｔの中心と電極中心４０とが一致するように接続位置を設定している。
また、複数の高周波電力配電体３２ａは、接続板（接続体）Ｃ３１の裏側面（プラズマ励起電極４側面）においても、同様に、正三角形Ｔの頂点に位置し、この正三角形Ｔの中心と接続板Ｃ３１の中心Ｃ３０とが一致するように接続位置を設定している。
そして、高周波電力配電体３１は、接続板Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）において、その中心Ｃ３０位置に接続されており、かつ電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌと平衡状態、つまりこの軸線Ｌと一致して設けられている。
ここで、プラズマ励起電極４か接続板Ｃ３１の接続面、つまり同一の接続面に接続される複数の高周波電力配電体３２ａにおける長さ寸法が等しく設定されることで、プラズマ励起電極４と接続板Ｃ３１との対向する接続面どうしを平行状態とすることができる。
【００５３】
ここで、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が剛体からなるとは、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が作動中に高周波特性が変化するような変形をしないこと、つまり、上記のような寸法のＣｕからなるものとされる。同時に、この剛体とは、取り外しおよび組み立てを伴う「メンテナンス前後で変形しない」「取り付け時における取り付け位置の再現性を有する」ことを意味している。具体的には、ネジ等の結合手段によって上述の変形しない高周波電力配電体３１，３２ａおよび接続板Ｃ３１が相互に接続されるとともに、およびこれらが、出力端子ＰＲ、プラズマ励起電極４と接続されるが、その際、接続状態の正確性が再現性を有するものとされるか、または、例えば溶接等により変形しないように接続されるものとされる。
【００５４】
高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面には、Ｃｕからなる中心部に比べてＡｕ，Ａｇのような低抵抗材料からなる低抵抗部ＲＬが設けられている。ここで、低抵抗部ＲＬの厚み寸法が、高周波電源１から供給される高周波電力周波数における表皮深さより大きく設定されている。
図５は高周波電力配電体３１，３２ａおよび接続板Ｃ３１の低抵抗部ＲＬおよび表皮深さδを説明するための断面図である。
ここで、表皮深さとは、図５に示すように、例えば、銅からなる高周波電力配電体３１，３２ａを交流電流ｉが流れているとき、この電流ｉによってできる円周方向の磁界も電流ｉとともに時間変化し、この電磁誘導によって電流の変化を妨げる方向に逆起電力が発生するが、このとき、導体断面の中心部の電流ほど磁束鎖交数が大きいので逆起電力も大きくなるため電流密度が小さくなり、結果として電流が表面付近を流れるようになる際に、高周波電力配電体３１，３２ａ内に、高周波電力配電体３１，３２ａ表面から電流ｉが浸み込む深さをいい、以下の式（２）で定義される。
【数２】

ここで、
δ：表皮深さ
ｆ：高周波電源から供給される高周波周波数
μ：透磁率（＝μ₀ 真空の透磁率）
σ：導電率
である。
【００５５】
例えば、高周波電源から１３．５６ＭＨｚ程度の周波数ｆの電力が供給されたとき、Ａｇとされる高周波電力配電体３１，３２ａの低抵抗部ＲＬにおける表皮深さとしては、
導電率σ＝１．１０×１０⁸ Ｓ／ｍ，透磁率μ＝μ₀ とすると、
表皮深さδ＝１．３０×１０ μｍ となり、
低抵抗部ＲＬの厚みは、δ＝１．３０×１０μｍより大きくなるよう、例えば、メッキ等により高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面に設けられる。
また、高周波電力配電体３２ａの接続されるＡｌ，Ｃｕ，ステンレス鋼等からなる電極４の接続板Ｃ３１側面にも、同様にして低抵抗部ＲＬを設ける（銀メッキする）ことができ、この際、給電部分の高周波抵抗を低減することが可能となる。
【００５６】
高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面は、絶縁体からなる絶縁被膜ＰＣによって覆われてなる。ここで、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面とは、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面全体を意味し、低抵抗部ＲＬが設けられている場合にはこの低抵抗部ＲＬの表面を覆うようになっている。
ここで、絶縁被膜ＰＣとしては、ポリイミド，ＰＦＡ（テトラフルオロエチレン−パーフルオロアルキルビニルエーテル共重合体）、ＰＴＦＥ（ポリテトラフルオロエチレン）、ＥＴＦＥ（テトラフルオロエチレン−エチレン共重合体）等が適応される。ここで、絶縁被膜ＰＣとしてポリイミド，ＰＦＡ（テトラフルオロエチレン−パーフルオロアルキルビニルエーテル共重合体）、ＰＴＦＥ（ポリテトラフルオロエチレン）を採用した場合には耐熱性に優れるという特性を生かすことができ、ＥＴＦＥ（テトラフルオロエチレン−エチレン共重合体）を採用した場合には、耐摩耗性に優れているという特性を生かすことができる。
【００５７】
本実施形態のプラズマチャンバ７５においては、１３．５６ＭＨｚ程度以上の周波数の電力、具体的には、例えば１３．５６ＭＨｚ，２７．１２ＭＨｚ，４０．６８ＭＨｚ等の周波数の電力を投入して、両電極４，８の間でプラズマを生成し、このプラズマにより、サセプタ電極８に載置した基板１６にＣＶＤ（ chemical vapor deposition）、ドライエッチング、アッシング等のプラズマ処理をおこなうことができる。
【００５８】
このとき、高周波電力は、高周波電源１から、給電部分として、給電線１Ａの同軸ケーブル，整合回路２Ａ，高周波電力配電体３１，接続板Ｃ３１，高周波電力配電体３２ａ，プラズマ励起電極（カソード電極）４に供給される。一方、高周波電流の経路を考えた場合、電流はこれら給電部分を介してプラズマ空間（チャンバ室６０）を経由した後、さらにもう一方の電極（サセプタ電極）８，シャフト１３，サセプタシールド１２，ベローズ１１，チャンバ底部１０Ａ，チャンバ壁１０を通り、その後、シャーシ２１，マッチングボックス２，給電線１Ａのシールド線を通り、高周波電源１のアースに戻る。
これら、シャフト１３，サセプタシールド１２，ベローズ１１，チャンバ底部１０Ａ，チャンバ壁１０、シャーシ２１，マッチングボックス２，給電線１Ａのシールド線は、それぞれ、高周波電源１から供給された高周波電流が高周波電源１のアース側に戻る経路、つまり、電流経路の復路を構成しているものである。
【００５９】
上記構成の処理室７５，７６，７７のいずれかにおいてアモルファスシリコン膜、シリコン酸化膜、シリコン窒化膜等の成膜をおこなう際には、サセプタ電極８上に被処理基板１６を載置し、高周波電源１から高周波電極４に高周波電力を印加するとともにガス導入管１７からシャワープレート６を介して反応ガスをチャンバ室６０内に供給してプラズマを発生させ、被処理基板１６上にアモルファスシリコン膜、シリコン酸化膜、シリコン窒化膜等を成膜する。
【００６０】
レーザアニール室７８は、図６に示すように、チャンバ８０の上部にレーザ光源８１が設けられる一方、チャンバ８０内の下部には被処理基板１６を載置するためのステージ８２が直交するＸ方向、Ｙ方向の２方向に水平移動可能に設けられている。そして、レーザ光源８１の出射部８１ａからスポット状のレーザ光８３（１点鎖線で示す）が出射されると同時に、被処理基板１６を支持したステージ８２がＸ方向、Ｙ方向に水平移動することにより、レーザ光８３が被処理基板１６の全面を走査できるようになっている。レーザ光源８１には例えばＸｅＣｌ、ＡｒＦ、ＡｒＣｌ、ＸｅＦ等のハロゲンガスを用いたガスレーザを用いることができる。
また、レーザアニール室７８の構成は、レーザ光を出射するレーザ光源を備え、レーザ光源から出射されるスポット状のレーザ光が被処理基板の表面をくまなく走査できる構成のものであれば、種々の構成の装置を用いることができる。この場合、レーザ光源は例えばＸｅＣｌ、ＡｒＦ、ＡｒＣｌ、ＸｅＦ等のハロゲンガスを用いたガスレーザを用いることができる。膜の種類によってはＹＡＧレーザ等の他のレーザ光源を用いることもでき、レーザ光の照射の形態としては、パルスレーザアニール、連続発振レーザアニールを用いることができる。また、熱処理室の構成は、例えば多段式電気炉型の装置を用いることができる。
【００６１】
熱処理室７９は、図７に示すように、多段式電気炉型のものであり、チャンバー８４内に多段に設けられたヒータ８５の各々に被処理基板１６が載置される構成になっている。そして、ヒータ８５の通電により複数枚の被処理基板１６が加熱されるようになっている。なお、熱処理室７９と搬送室７２との間にはゲートバルブ８６が設けられている。
【００６２】
図１に示すローダ室７３、アンローダ室７４には、ローダカセット、アンローダカセットが着脱可能に設けられている。これら２つのカセットは、複数枚の被処理基板１６が収容可能なものであり、ローダカセットに成膜前の被処理基板１６が収容され、アンローダカセットには成膜済の被処理基板１６が収容される。そして、これら処理室ユニットとローダ室７３、アンローダ室７４の中央に位置する搬送室７２に基板搬送ロボット（搬送手段）８７が設置されている。基板搬送ロボット８７はその上部に伸縮自在なリンク機構を有するアーム８８を有し、アーム８８は回転可能かつ昇降可能となっており、アーム８８の先端部で被処理基板１６を支持、搬送するようになっている。
【００６３】
上記構成のプラズマ処理装置７１は、例えば各処理室ユニットにおける成膜条件、アニール条件、熱処理条件等、種々の処理条件や処理シーケンスをオペレータが設定する他は、各部の動作が制御部により制御されており、自動運転する構成になっている。したがって、このプラズマ処理装置７１を使用する際には、処理前の被処理基板１６をローダカセットにセットし、オペレータがスタートスイッチを操作すれば、基板搬送ロボット８７によりローダカセットから各処理室内に被処理基板１６が搬送され、各処理室で一連の処理が順次自動的に行われた後、基板搬送ロボット８７によりアンローダカセットに収容される。
【００６４】
ここで、本実施形態のプラズマ処理装置７１のプラズマチャンバ７５における配電体部分３の高周波特性について説明する。
【００６５】
本実施形態のプラズマチャンバ７５の配電体部分（高周波電力配電体）３においては、出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電源１から供給される高周波電力の単位体積当たりの平均密度の最大値が粗になるよう設定されている。
ここで、「電力の平均密度」とは、高周波電力配電体３１，３２ａおよびその周囲の空間を含めて「空間を伝播するエネルギーをその伝播方向に徴小な長さδｉに対応する板状の空間内における単位体積あたりのエネルギーの平均値」を意味するものであり、この電力の平均密度が粗になるとは、図３に示すように、チューニングコンデンサ２４の出力端子とされる整合回路の出力端子ＰＲからプラズマ励起電極４までの電流の伝播方向に対してｉ軸を設定し、このｉ軸上で徴小な長さδｉに対応するｉ軸に垂直な板状の空間ΔＶにおいて、その中の高周波電力配電体３１，３２ａ近傍における徴小な体積δＶにおけるエネルギー密度が、ｉ軸に沿って整合回路の出力端子ＰＲ側からプラズマ励起電極４側に向かって減少することを意味しており、具体的には、出力端子ＰＲ側からプラズマ励起電極４側に向かって、電流の流れる部分の本数が、高周波電力配電体３１単独の１本から高周波電力配電体３２ａの３本に増大している状態により実現され、これは、単純に云っても、ｉ軸と直交する面における高周波電力配電体３１，３２ａの断面積が広がっており、高周波電流伝送経路としての高周波電力配電体３１，３２ａの表面積が広がっていることからもわかる。
【００６６】
これにより、高周波電力配電体３における高周波電流の伝播する空間が広がり、実質的にインダクタンスが低減するとともに、高周波抵抗が減少する。つまり、高周波電力配電体３が複数本からなることにより、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、配電体部分３における高周波電流に対する制限を低減することができる。同時に、配電体部分３において、チューニングコンデンサ２４の出力端子とされる例えばボルト一本程度の太さの整合回路２Ａ出力端子ＰＲから、プラズマ励起電極４まで高周波電力の伝播する空間が拡大し、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスを低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力を増大することが可能となる。つまり、同一周波数を供給した場合に、従来のプラズマ処理装置と比べてプラズマ空間で消費される実効的な電力の増大を図ることができ、膜の積層をおこなう際には、堆積速度の向上を図ることができるように、プラズマ処理結果の向上を図ることが可能となる。
【００６７】
本実施形態のプラズマチャンバ７５の配電体部分（高周波電力配電体）３においては、プラズマ励起電極４側の高周波電力配電体３２ａが複数本からなることにより、高周波電力配電体３１が単数本からなる部分に比べて、配電体部分３において、特に高周波電力配電体３２ａにおいて、高周波電源からプラズマ励起電極４まで供給される高周波電力の単位体積当たりの平均密度を粗にするよう設定することができる。
ここで、図３に示すように、高周波電力配電体３２ａの本数を３本に設定した場合における、ｉ軸に垂直な板状の空間ΔＶ２中の単位体積δＶ２当たり「伝播する高周波電力のエネルギー密度」と、高周波電力配電体３１が単数本からなる場合における、ｉ軸に垂直な板状の空間ΔＶ１中の単位体積δＶ１当たり「伝播する高周波電力のエネルギー密度」とを比較する。すると、ｉ軸に垂直な板状の空間ΔＶ２における高周波電力の伝播する部分空間は、ΔＶ１における高周波電力の伝播する高周波電力配電体３１表面および高周波電力配電体３１周囲の部分空間に対応して、高周波電力配電体３２ａの本数に関連して３倍の大きさになっている。このため、高周波電力配電体３２ａの本数に対応して、ｉ軸に垂直な板状の空間ΔＶ２において、高周波電源１から供給された高周波電流が伝播するための空間が大きくなっているといえる。
【００６８】
結果的に、高周波電力配電体３２ａが複数本からなることにより、高周波電力の伝播する部分空間におけるエネルギー密度が減少して、実質的にインダクタンスを低減するとともに、高周波抵抗を減少し、結果的に、高周波電源１からプラズマ励起電極４までの給電部分における高周波電力の伝播する部分空間におけるエネルギー密度をより減少し、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限をいっそう低減することができ、同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスをより低減することができる。その結果、プラズマ発生空間に供給される実効的な高周波電力をさらに増大することが可能となる。高周波電流に対する制限を低減することができ、さらに、プラズマ発生空間に供給される高周波電力のロスを低減することが可能となる。
これにより、同一周波数を供給した場合に、従来のプラズマ処理装置と比べてプラズマ空間で消費される実効的な電力の上昇を図ることができ、処理速度が向上する、例えば、プラズマＣＶＤ等により膜の積層をおこなう場合には、堆積速度の向上を図ることができる。また、プラズマ空間で消費される実効的な電力を変えずに、プラズマ励起周波数の高周波化により、処理速度の向上を図ることができる。
【００６９】
さらに、複数の高周波電力配電体３２ａをプラズマ励起電極４に接続することで、プラズマ励起電極４に対して図４に示す正三角形Ｔの頂点とされる複数点から高周波電力を供給することができるため、単点から高周波電力を供給する際に問題となっていた、プラズマ励起電極４のサイズ（給電位置から電極周辺までの最長距離）がプラズマ励起周波数（高周波電力周波数）の１／４波長に比べて大きい場合に定在波が原因で、プラズマ発生空間に発生するプラズマ密度に分布が生じ、プラズマ処理に被処理基板面内方向への不均一が生じて、膜厚や膜質の基板面内での均一性が損なわれることを防止することができる。
【００７０】
なお、複数の高周波電力配電体３２ａをプラズマ励起電極４に接続することで、プラズマ励起電極４に対して図４に示す正三角形Ｔ以外にも、図８に示すように、電極中心４０に対して対称な２点、あるいは、電極中心に対して対称な多角形を形成するようにでき、例えば、図９、図１０に示すような正方形Ｑ、図１２に示すような正５角形ＱＵ、あるいは、正６角形、…の頂点とされる複数点から高周波電力を供給することができる。
【００７１】
複数の高周波電力配電体３２ａが、互いに平行状態に設けられてなることにより、この複数の高周波電力配電体３２ａ表面を伝播する高周波電流が、複数の高周波電力配電体３２ａ間の空間に作る磁界、つまりｉ軸に直交する面でみると正三角形Ｔ内部とされる空間にできる磁界が互いに打ち消し合うとともに、この打ち消し合いが、伝播方向（ｉ軸方向）における複数の高周波電力配電体３２ａ間の距離が等しい範囲、つまり、ｉ軸方向で接続板Ｃ３１とプラズマ励起電極４との間の範囲において等しい状態に設定できるため、配電体部分３におけるインダクタンスを低減することができ、これによって、より一層プラズマ発生空間に供給される高周波電力のロスを低減することが可能である。
これにより、同一周波数を供給した場合に、従来のプラズマ処理装置と比べてプラズマ空間で消費される実効的な電力の上昇を図ることができ、処理速度が向上する。例えば、プラズマＣＶＤ等により膜の積層をおこなう場合には、堆積速度の向上を図ることができる。また、プラズマ空間で消費される実効的な電力を変えずに、プラズマ励起周波数の高周波化により、処理速度の向上を図ることができる。
【００７２】
また、複数の高周波電力配電体３２ａが、プラズマ励起電極４の中心に対して軸対称な状態、つまり、３本の高周波電力配電体３２ａ間の距離をそれぞれ等しく配置してプラズマ励起電極４に接続されているため、複数の高周波電力配電体３２ａが上記のｉ軸に垂直な板状の空間ΔＶ２に作る磁界を互いに打ち消し合うようにでき、配電体部分３におけるインダクタンスをより一層低減することができる。同時に、複数の高周波電力配電体３２ａが、プラズマ励起電極４の中心に対して軸対称な状態でプラズマ励起電極４に接続されてなることにより、プラズマ励起電極４における偏流の発生を防止して、プラズマ発生空間におけるプラズマ密度に分布が生じ膜厚や膜質の基板面内での均一性が損なわれることを防止することができる。
【００７３】
複数の高周波電力配電体３２ａが接続板Ｃ３１によって互いに接続されてこの接続板Ｃ３１が高周波電力配電体３１に接続されていることにより、接続板Ｃ３１を設けない場合に比べて、整合回路の２Ａ出力端子ＰＲからプラズマ励起電極４までの配電体部分３において供給される高周波電力の単位体積当たりの平均密度を粗にする際に、プラズマ励起電極４に接続される高周波電力配電体３２ａどうしの間隔を大きく設定することができるため、高周波電力の伝播する部分空間におけるエネルギー密度をより減少し、実質的にインダクタンスがさらに低減して高周波抵抗が減少し、結果的に、高周波電源１からプラズマ励起電極４に至る給電部分における高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限を低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスを低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力を増大することが可能となる。
これにより、プラズマ励起電極４に接続される高周波電力配電体３２ａどうしの間隔を大きく設定することができることで、プラズマ励起電極４に対して複数点から高周波電力を供給して、給電位置からプラズマ励起電極４のサイズがプラズマ励起周波数（高周波電力周波数）の１／４波長に比べて大きい箇所が存在する程度にプラズマ励起電極４が大きい場合であっても、定在波によりプラズマ密度に分布が生じ、膜厚や膜質の基板面内での均一性が損なわれることをより効果的に防止することが可能となる。
【００７４】
接続板Ｃ３１には、プラズマ励起電極４に略平行な面が設けられてなることにより、この面に対して複数の高周波電力配電体３２ａを電極中心４０の中心軸線Ｌに対して対称な状態で接続板Ｃ３１に接続することができて、高周波電流の伝播方向（ｉ軸方向）と直交する面が設けられるため、長さの等しい複数の高周波電力配電体３２ａを設けて、高周波電力配電体３２ａの高周波インピーダンスを容易に同じくすることができ、各高周波電力配電体３２ａを流れる電流を等しくすることができ、偏流防止にさらに効果的である。また、このような高周波電力配電体を用いることにより、偏流を防止して、接続体Ｃ３１およびプラズマ励起電極４間において、高周波電力の伝播する部分空間におけるエネルギー密度をより減少し、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限をいっそう低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスをより低減することができる。その結果、プラズマ発生空間で消費される実効的な高周波電力をさらに増大することが可能となる。
【００７５】
さらに、複数の高周波電力配電体３２ａが、前記接続板Ｃ３１の中心Ｃ３０に対して軸対称な状態で接続板Ｃ３１に接続されてなることにより、接続板Ｃ３１中心Ｃ３０を通る中心軸線Ｌに対して対称に接続することにより、接続板Ｃ３１から高周波電力配電体３２ａへ流れる高周波電流における偏流を防止して、プラズマ密度に分布が生じ膜厚や膜質の被処理基板面内での均一性が損なわれることを防止することができるとともに、インダクタンスを低減して、プラズマ発生空間に供給される高周波電力のロスをさらに低減することが可能となる。
【００７６】
接続板Ｃ３１が、プラズマ励起電極４と相似形状の板状体とされてなることにより、板状体とされた接続板Ｃ３１の両側面に高周波電力配電体３２ａを接続するとき、接続板Ｃ３１の出力端子ＰＲ側面とプラズマ励起電極４側面とにおける高周波電力配電体の接続状態を、供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定することで、高周波電力が伝播する空間を電極と相似形状として大きくすることができる。これにより、整合回路２Ａの出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電力が伝播する空間を大きくする際に、偏流を防止してプラズマ密度に分布が生じ膜厚や膜質の被処理基板面内での均一性が損なわれることを防止することができるとともに、給電部分の高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限をさらに低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスをより一層低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力をさらに増大することが可能となる。
【００７７】
複数の高周波電力配電体３２ａにおける径寸法、断面形状、長さ寸法等の形状が等しく設定されて、これらの高周波電力配電体３２ａにおける高周波特性が互いに等しく設定されてなることにより、電流伝播経路としての複数の高周波電力配電体３２ａにおける高周波抵抗、インダクタンスを等しくして、偏流の発生を防止して、プラズマ密度に分布が生じ膜厚や膜質の基板面内での均一性が損なわれることを防止することができる。
【００７８】
なお、本実施形態では高周波電力配電体３２ａの断面形状を円形としたが、これ以外にも、図９に示す正方形や、図１５に示す断面矩形、図１１に示す正３角形、図１２に示す正５角形等の断面多角形、あるいは、上述の剛体となるように、図１０，図１３に示す断面Ｌ字状とされた板状体、図１４に示す断面Ｔ字状の板状体として設定することも可能である。この場合、図１５に示すように、電流伝播経路に沿った方向から見た接続状態がそれぞれ相似になるように、高周波電力配電体３２ａどうしの接続位置の比率、接続角度（接続板Ｃ３１またはプラズマ励起電極４の接続面と高周波電力配電体３２ａの軸線Ｌ方向との角度）等の条件が等しくなるよう設定される。
具体的には、図１３に示すように、高周波電力配電体３２ａのＬ字状の一端が電極中心４０を向くようにこの高周波電力配電体３２ａが設けられた際に、高周波電力配電体３２ａのＬ字状の他端は、それぞれ電極４の輪郭である円周方向同一の方向を向くように接続されるように設定される。また、図１４に示すように、図に破線で示す電極中心４０から各高周波電力配電体３２ａの接続位置に向かう直線に対して、高周波電力配電体３２ａのＴ字状の一端がいずれも同じ角度−この場合は平行−に接続されるように設定される。
【００７９】
また、高周波電力配電体３１および高周波電力配電体３２ａにおける径寸法、断面形状、長さ寸法等の形状が等しく設定されて、これらの高周波電力配電体３１，３２ａにおける高周波特性が互いに等しく設定されてなることにより、個々の高周波電力配電体３１，３２ａにおけるインダクタンスおよび高周波抵抗を互いに等しく設定することができ、個々に流れる電流を等しくすることができ、これにより、複数併設された高周波電力配電体３２ａ，３２ａどうしでその内部空間位置における誘導磁界のキャンセルが効率的になり配電体部分３におけるインダクタンスを低減するが可能となる。同時に、個々に流れる電流を等しくすることにより、プラズマ励起電極４への高周波電流の偏流を防止することができ、プラズマ発生空間において発生したプラズマの分布を向上しプラズマ処理における被処理基板面内方向における処理の分布発生を防止することができる。
また、高周波電力配電体３１および高周波電力配電体３２ａにおいて、剛性を保持するように形状が設定されてなる剛体とされていることにより、これらの高周波電力配電体３１，３２ａにおけるインダクタンスおよび高周波抵抗等の高周波特性をそれぞれ安定させることができる。これにより、プラズマ処理進行に伴うプラズマ処理装置の経時変化によっても発生する可能性があるプラズマ処理のばらつきを防止し、時間的に均一で安定したプラズマ処理をおこなうことができ、特に、複数回のプラズマ処理をおこなう際、回を重ねるごとに、それぞれのプラズマ処理結果を安定させることができる。
さらに、上述のように電極中心４０に対して高周波電力配電体３１および高周波電力配電体３２ａの配置を対称にすることにより、高周波電流における偏流の発生を防止して、プラズマ発生空間において発生したプラズマの分布を向上しプラズマ処理における被処理基板面内方向における処理の分布発生を防止することができる。
【００８０】
高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面には、中心部に比べて低抵抗材料からなる低抵抗部ＲＬが設けられてなることにより、表皮効果により高周波電力配電体３１，３２ａおよび接続板Ｃ３１表面付近のみを流れる高周波電流に対して、この高周波電流の伝播する部分における高周波抵抗を、より低減することが可能となる。その結果、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の太さや長さなどの形状に依存することなく、高周波抵抗を最小化でき、プラズマ発生空間に供給される高周波電力のロスをさらに低減することが可能となる。
【００８１】
なお、低抵抗部ＲＬは、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の基材（中心部）がＡｌ，ステンレス鋼等からなる場合には、低抵抗材として、例えば、Ａｕ，Ａｇ，Ｃｕおよびこれらを含む合金等を適応することができる。また、この低抵抗部ＲＬは、高周波電力配電体３１，３２ａの表面全体、接続板Ｃ３１の表裏面全体あるいは、これらの一部分、例えば、高周波電流の伝播経路として設定した場合に好ましい箇所のみに設けることも可能である。
このような構成の例として、図２８に示すように、高周波電力配電体３１，３２ａにおいては図示しないが低抵抗部が全面に設けられ、同時に、接続体Ｃ３１においては、高周波電力配電体３１の接続される高周波電源側（後述する出力端子ＰＲ側）の面と側面には表面全体に低抵抗部ＲＬが設けられるとともに、高周波電力配電体３２ａの接続される電極側の面には、各高周波電力配電体３２ａの接続される位置より中心Ｃ３０側には低抵抗部ＲＬを設けず、各高周波電力配電体３２ａの接続される位置より外側つまり縁側には低抵抗部ＲＬを設けることができる。これにより、表皮効果により高周波電流が沿って流れる際にこの高周波電流に対する影響の大きい表面部分にのみ低抵抗部を設けることになる。
上記の例としては、いずれも、後述するように図４に示す正三角形Ｔ、図１９に示す正三角形Ｔ１〜Ｔ３、図９に示すような正方形Ｑ、図１０に示すような正５角形ＱＵ、あるいは、正６角形、…の頂点で形成される高周波電力配電体３２ａの接続される位置を結んで形成される多角形の内側、つまり中心Ｃ３０側に対応する部分に低抵抗部を設けないことが可能である。
【００８２】
また、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面全体にＡｕ，Ａｇおよびこれらを含む合金等のように低腐食性の材料からなる低抵抗部を設けた場合には、プラズマ処理時における高周波電流による発熱、腐食、酸化等に起因する抵抗値上昇やその他の変質などの経時変化が発生することを抑制し、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の基材および低抵抗部を保護して、高周波抵抗の変化を防止し、再現性の高いプラズマ処理を安定しておこなうことが可能となる。
【００８３】
前記低抵抗部ＲＬの厚み寸法が、高周波電源１から供給される高周波電力周波数ｆに対して式（２）で規定される表皮深さδより大きく設定されることにより、高周波電流の流れる部分の抵抗値を低減することができるため、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の基体の強度等に影響を与えることなく、高周波抵抗を低減して、プラズマ発生空間に供給される高周波電力のロスをさらに低減することが可能となる。
【００８４】
また、低抵抗部ＲＬ表面を含んで高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面全体が、絶縁体からなる絶縁被膜によって覆われてなることにより、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が酸化することを防止でき、配電体部分３における高周波抵抗の変動を抑制することが可能となり、高周波電力配電体３１，３２ａおよび接続板Ｃ３１に生じる高周波特性の経時変化に起因するプラズマ処理の変動要因を抑制し、再現性が高く安定したプラズマ処理をおこなうことができ、特に、複数回のプラズマ処理をおこなう際においても、それぞれのプラズマ処理結果を安定させることができるようになる。
なお、高周波電力配電体３１，３２ａおよび接続板Ｃ３１の表面全体にＡｕ，Ａｇおよびこれらを含む合金等のように低腐食性の材料からなる低抵抗部を設けた場合には、絶縁被膜を設けないこともできる。
【００８５】
さらに、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が、作動中に高周波特性が変化するような変形をしないこと、および、取り外しや組み立てを伴うメンテナンス前後で変形せず、かつ、取り付け時における取り付け位置の再現性を有すること、が可能な剛体とされていることにより、プラズマ処理進行に伴ったプラズマチャンバ７５，７６，７７の経時変化により発生する可能性があるプラズマ処理のばらつき、特に、高周波電力配電体３１，３２ａおよび接続板Ｃ３１に生じる変形によりこの部分の高周波特性が変化することに起因するプラズマ処理経時変化の変動要因を抑制し、時間的に均一で安定したプラズマ処理をおこなうことができ、特に、複数回のプラズマ処理をおこなう際、回を重ねるごとに、それぞれのプラズマ処理結果を安定させ、再現性の高いプラズマ処理をおこなうことが可能となる。
【００８６】
プラズマチャンバ７５，７６，７７のチャンバ壁１０に接続されるシャーシ（遮蔽導体）２１内部に、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が収容されている、つまり、高周波電源１から供給された高周波電流における電流経路の復路を構成しているシャーシ２１，マッチングボックス２内部に高周波電力配電体３１，３２ａおよび接続板Ｃ３１が収容されていることにより、プラズマチャンバ７５，７６，７７の外部への不要輻射を遮蔽でき、配電体部分３における高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限を低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスを低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力を増大することが可能となる。
【００８７】
本実施形態のプラズマ処理装置７１においては、複数のプラズマチャンバ７５，７６，７７のそれぞれにおいて 配電体部分３のインピーダンス、高周波抵抗等の電気的高周波的な特性を個別に設定することにより、これら複数のプラズマチャンバ７５，７６，７７間の電気的高周波的な機差を低減することが可能となり、個々のプラズマチャンバにおいて、プラズマ空間で消費される実効的な電力のロスを低減しつつその差を低減することができる。
その結果、複数のプラズマチャンバ７５，７６，７７に対して同一のプロセスレシピを適用して、略同一のプラズマ処理結果を得ること、つまり、複数のプラズマチャンバ７５，７６，７７において例えば成膜をおこなった際に、膜厚、絶縁耐圧、エッチングレート等、略均一な膜特性の膜を得ることが可能となる。具体的には、それぞれのプラズマチャンバ７５，７６，７７において、給電板３として、幅５０〜１００ｍｍ、厚さ０．５ｍｍ、長さ１００〜３００ｍｍの形状を有する銅板を用いた場合に比べて、プラズマ空間で消費される実効的な電力を５０％程度増大することができる。
【００８８】
さらに、高周波電力配電体３１，３２ａおよび接続板Ｃ３１が、作動中に高周波特性が変化するような変形しないこと、および、取り外しや組み立てを伴うメンテナンス前後で変形せず、かつ、取り付け時における取り付け位置の再現性を有すること、が可能な剛体とされていることにより、処理をおこなった基板の評価によりプラズマ処理装置７１の動作確認、動作の評価をおこない、配電体部分３の調整をおこなうという２段階のメンテナンスをおこなう必要がなく、新規設置時や調整・メンテナンス時において、各プラズマチャンバ７５，７６，７７ごとの機差を低減して処理のばらつきを実質的になくし同一のプロセスレシピにより略同一の処理結果を得るために必要な調整時間を、大幅に短縮することができる。その上、被処理基板１６への実際の成膜等による検査方法を採用した場合、別々におこなうしかなかった複数のプラズマチャンバ７５，７６，７７に対する結果をほぼ同時に実現することができる。また、このような被処理基板の評価によるプラズマ処理装置７１の動作確認調整に必要な検査用基板等の費用、この検査用基板の処理費用、および、調整作業に従事する作業員の人件費等、コストを大幅に削減することが可能となる。
【００８９】
なお、本実施形態においては、プラズマチャンバ７５，７６，７７において、サセプタ電極側８に基板１６を載置してプラズマ励起電極４に対する配電体部分３の高周波特性の設定をおこなうよう設定したが、ＲＩＥ（reactive ion etching）反応性スパッタエッチングに対応するようにカソード電極４側に基板１６を取り付けるよう対応することも可能である。
【００９０】
以下、本発明に係るプラズマ処理装置およびプラズマ処理システムの第２実施形態を、図面に基づいて説明する。
［第２実施形態］
図１６は本実施形態のプラズマ処理装置９１の概略構成を示す断面図である。
本実施形態のプラズマ処理装置９１は、図１６に示すように、略四角形の搬送室９２の周囲にロードロック室９３と熱処理室９９と処理室９５，９６とが設けられた構成とされている。この装置は基板移載用の搬送ロボットが設置されている搬送室９２を中央にして、各室の間が、ゲートｇ１，ｇ２，ｇ３，ｇ４で区切られている。搬送室（待機室）９２と加熱室９９とその他の処理室ユニット９５，９６はそれぞれ個別の高真空ポンプによって高真空度に排気されている。ロードロック室９３は低真空ポンプによって低真空度に排気されている。
【００９１】
本実施形態のプラズマ処理装置９１においては、その構成要素が図１〜図１５に示した第１実施形態のプラズマ処理装置７１に対応しており、それぞれ、搬送室７２に搬送室９２が、熱処理室７９に熱処理室９９が、ロードロック室９３がローダ室７３およびアンローダ室７４に対応しており、略同一の構成の部分に関しては説明を省略する。
【００９２】
プラズマ処理室ユニット（プラズマチャンバ）９５，９６は、図１〜図１５に示した第１実施形態のプラズマ処理室ユニット（プラズマチャンバ）７５，７６に対応して、それぞれ異なる種類の膜を成膜するような異なる処理をおこなうことも可能であり、また、同一のプロセスレシピにより同一の処理をおこなうこともできるものであるが、略同一の構成とされている。
そして、これらの複数のプラズマ処理室ユニット（プラズマチャンバ）９５，９６は、配電体部分３において、高周波電力配電体３１，３２ｂ〜３４ｂが複数本からなるとともに、高周波電力配電体３１，３２ｂ〜３４ｂが複数の接続体Ｃ３１〜Ｃ３３によって互いに接続され前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１から前記電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定された構成とされている。
ここではプラズマ処理室ユニット９５を例に挙げてその構成を説明する。
【００９３】
図１７は本実施形態のプラズマ処理室ユニット（プラズマチャンバ）の概略構成を示す断面図、図１８は図１７におけるプラズマ処理室ユニット（プラズマチャンバ）の配電体部分３を示す正面図、図１９は図１７の配電体部分３およびプラズマ励起電極４を示す平面図である。
【００９４】
本実施形態のプラズマ処理室ユニット（プラズマチャンバ）９５は、２周波数励起タイプのプラズマ処理室とされ、図１〜図１５に示した第１実施形態のプラズマ処理室７５と異なるのはサセプタ電極８側に電力を供給する点と、配電体部分３の構造に関する点である。それ以外の対応する構成要素には同一の符号を付してその説明を省略する。
本実施形態のプラズマチャンバ９５，９６は、配電体部分３において、高周波電力配電体３１，３２ｂ〜３４ｂが複数の接続体Ｃ３１〜Ｃ３３によって互いに接続され前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１から前記電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定された構成とされている。
【００９５】
本実施形態のプラズマチャンバ９５は、図１７〜図１９に示すように、サセプタ電極８の周囲にサセプタシールド１２が設けられ、ウエハサセプタ８およびサセプタシールド１２は、これらの隙間がシャフト１３の周囲の設けられた電気絶縁物からなる絶縁手段１２Ｃによって真空絶縁されるとともに電気的にも絶縁されている。また、ウエハサセプタ８およびサセプタシールド１２は、ベローズ１１により上下動可能に構成されている。この構成により、プラズマ励起電極４とサセプタ電極８との間の距離が調整可能となっている。また、サセプタ電極８は、シャフト１３下端に接続された給電板２８、および、導電体からなるサセプタ電極側マッチングボックス２６内部に収納された整合回路２５を介して第２の高周波電源２７と接続されている。
【００９６】
この給電板２８としては、例えば、幅５０〜１００ｍｍ、厚さ０．５ｍｍ、長さ１００〜３００ｍｍの形状を有する銅の表面に銀めっきを施したものが用いられており、この給電板２８は、後述する整合回路２５のチューニングコンデンサ３１の出力端子およびシャフト１３下端にそれぞれネジ止めなどの結合手段により着脱可能に取り付けられている。
給電板２８は、サセプタシールド１２の支持筒１２Ｂ下端に接続されたシャーシ２９に覆われるとともに、シャーシ２９は、同軸ケーブルとされる給電線２７Ａのシールド線によって接続されマッチングボックス２６とともにアースされている。これにより、サセプタシールド１２，シャーシ２９，マッチングボックス２９は直流的に同電位となっている。
【００９７】
ここで、整合回路２５は、第２の高周波電源２７とサセプタ電極８との間のインピーダンスの整合を図るものとされ、この整合回路２５としては、図１７に示すように、複数の受動素子として、第２の高周波電源２７と給電板２８との間に、チューニングコイル３０とチューニングコンデンサ３１とが直列に設けられ、これらと並列にロードコンデンサ３２が接続され、このロードコンデンサ３２の一端はマッチングボックス２６に接続されており、整合回路２Ａと略同様の構成とされている。マッチングボックス２６は給電線２７Ａのシールド線を介して接地電位に設定されており、同時に、ロードコンデンサ３２の一端がアースされている。なお、チューニングコイル３０と直列にチューニングコイルを接続することや、ロードコンデンサ３２と並列にロードコンデンサを設けることも可能である。
【００９８】
本実施形態のプラズマチャンバ９５においては、サセプタ電極８上に被処理基板１６を載置し、第１、第２の高周波電源１，２７からプラズマ励起電極４とサセプタ電極８の双方にそれぞれ高周波電力を印加するとともにガス導入管１７からシャワープレート６を介して反応ガスをチャンバ室６０内に供給してプラズマを発生させ、被処理基板１６に対して成膜等のプラズマ処理をおこなう。このとき、第１の高周波電源１から１３．５６ＭＨｚ程度以上の周波数の電力、具体的には、例えば１３．５６ＭＨｚ，２７．１２ＭＨｚ，４０．６８ＭＨｚ等の周波数の電力を投入する。そして、第２の高周波電源２７からも第１の高周波電源１からと同等か、異なる周波数の電力、例えば１．６ＭＨｚ程度の電力を投入することもできる。
【００９９】
配電体部分３としては、図１８に示すように、いずれも断面円形状で径寸法２〜１０ｍｍ、長さ寸法１００〜３００ｍｍの等しい形状を有する棒状の銅からなる高周波電力配電体３１，３２ｂ〜３４ｂが複数の接続板（接続体）Ｃ３１〜Ｃ３３によって互いに接続されている。これら高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３は剛体とされている。
ここでは、接続板Ｃ３１〜Ｃ３３は、いずれもプラズマ励起電極４より小さくいずれも同じ厚さでプラズマ励起電極４と相似状態の銅からなる円板とされ、かつ、いずれもプラズマ励起電極４と平行状態に対向して整合回路２Ａの出力端子ＰＲからプラズマ励起電極４までの間に、接続板Ｃ３１、接続板Ｃ３２、接続板Ｃ３３、の順に径方向寸法が大きくなるよう多段に設けられている。
ここで、接続板Ｃ３１〜Ｃ３３がプラズマ励起電極４と相似状態となるとは、電流伝播経路に沿った方向（ｉ軸方向）から見た接続板Ｃ３１〜Ｃ３の輪郭形状がそれぞれ相似になるということを意味している。
【０１００】
高周波電力配電体３１の一端は、整合回路２Ａの出力端子ＰＲとされるチューニングコンデンサ２４の出力端子にネジ止めなどの結合手段により着脱可能に取り付けられており、高周波電力配電体３１の他端は接続板（接続体）Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）に直交して接続されている。
【０１０１】
そして、接続板Ｃ３１の裏側面（プラズマ励起電極４側面）には複数の高周波電力配電体３２ｂが垂設され、これら高周波電力配電体３２ｂの他端が接続板Ｃ３２の表側面（整合回路２Ａの出力端子ＰＲ側面）に直交して接続されている。接続板Ｃ３２の裏側面（プラズマ励起電極４側面）には複数の高周波電力配電体３３ｂがその一端で接続されて垂設され、これら高周波電力配電体３３ｂの他端が接続板Ｃ３３の表側面（整合回路２Ａの出力端子ＰＲ側面）に直交して接続されている。接続板Ｃ３３の裏側面（プラズマ励起電極４側面）には複数の高周波電力配電体３４ｂがその一端で接続されて垂設され、これら高周波電力配電体３４ｂの他端がプラズマ励起電極４表面に直交して接続されている。これら高周波電力配電体３１，３２ｂ〜３４ｂは、いずれもプラズマ励起電極４と直交する方向とされる出力端子ＰＲからプラズマ励起電極４までの電流の伝播方向のｉ軸と平行に設けられている。
【０１０２】
本実施形態の高周波電力配電体３１，３２ｂ〜３４ｂにおいて、前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１からプラズマ励起電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定されてなる。言い換えると、チューニングコンデンサ２４の出力端子ＰＲに取り付けられた一本の高周波電力配電体３１の一端から、プラズマ励起電極４表面に接続された複数本の高周波電力配電体３４ｂの他端にむかって、高周波電力配電体３１，３４ｂにおける高周波電流の伝播する空間が広がり、実質的にインダクタンスが低減するとともに、高周波抵抗が減少するようになっている。
具体的には、配電体部分３の一段目においては、接続板Ｃ３１の表側面（出力端子ＰＲ）側が一本の高周波電力配電体３１、接続板Ｃ３１の裏側面（接続板Ｃ３２の表側面）側が３本の高周波電力配電体３２ｂとされて、高周波電流の伝播する空間が約３倍になっている。
また、配電体部分３の２段目においては、接続板Ｃ３２の表側面の高周波電力配電体３２ｂどうしの間隔よりも接続板Ｃ３２の裏側面（接続板Ｃ３３の表側面）における高周波電力配電体３３ｂどうしの間隔が大きく設定されて高周波電流の伝播する空間が広がっている。
さらに、配電体部分３の３段目においては、接続板Ｃ３３の表側面の高周波電力配電体３３ｂどうしの間隔よりも接続板Ｃ３３の裏側面（プラズマ励起電極４）における高周波電力配電体３４ｂどうしの間隔が大きく設定されて高周波電流の伝播する空間がさらに広がっている。
【０１０３】
ここで、１本の高周波電力配電体３１は、接続板Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）において、その中心Ｃ３０位置に接続されており、かつ電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌと平行状態、つまりこの軸線Ｌと一致して設けられている。
３本の高周波電力配電体３２ｂは、互いに平行状態とされて、かつ、円形のプラズマ励起電極４の中心４０に対して軸対称な状態で接続板Ｃ３１の裏側面（プラズマ励起電極４側面）および接続板Ｃ３２の表側面（整合回路２Ａの出力端子ＰＲ側面）に接続されている。ここで、軸対称とは、電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌに対して空間的に対称なこと、つまり、それぞれの高周波電力配電体３２ｂは、図１９に示すように、正三角形Ｔ１の頂点に位置し、この正三角形Ｔ１の中心，電極中心４０および，接続板Ｃ３１の中心Ｃ３０，接続板Ｃ３２の中心Ｃ３０，とがそれぞれ一致するように接続位置を設定している。
【０１０４】
また、３本の高周波電力配電体３３ｂは、互いに平行状態かつ、軸線Ｌに対して平行とされて、円形のプラズマ励起電極４の中心４０に対して軸対称な状態で接続板Ｃ３２の裏側面および接続板Ｃ３３の表側面に接続されている。ここで、軸対称とは、電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌに対して空間的に対称なこと、つまり、それぞれの高周波電力配電体３３ｂは、図１９に示すように、正三角形Ｔ２の頂点に位置し、この正三角形Ｔ２の中心，電極中心４０および，接続板Ｃ３２の中心Ｃ３０，接続板Ｃ３３の中心Ｃ３０，とがそれぞれ一致するように接続位置を設定している。
そして、３本の高周波電力配電体３４ｂは、互いに平行状態かつ、軸線Ｌに対して平行とされて、円形のプラズマ励起電極４の中心４０に対して軸対称な状態で接続板Ｃ３３の裏側面およびプラズマ励起電極４に接続されている。ここで、それぞれの高周波電力配電体３４ｂは、図１９に示すように、正三角形Ｔ３の頂点に位置し、この正三角形Ｔ３の中心，電極中心４０および，接続板Ｃ３３の中心Ｃ３０，とがそれぞれ一致するように接続位置を設定している。
【０１０５】
このように配電体部分３においては、それぞれの接続板Ｃ３１〜Ｃ３３の表面と裏面とで、それぞれ相似状態となるように前記複数の高周波電力配電体３２ｂ〜３４ｂが接続されている、つまり、それぞれの接続板Ｃ３１〜Ｃ３３における高周波電力配電体３２ｂ〜３４ｂの接続位置を示す正三角形Ｔ１〜Ｔ３が相似状態かつその方向も等しく（頂点の方向が一致した状態で）設けられている。
【０１０６】
ここで、接続板Ｃ３１の接続面、つまり同一の接続面に接続される複数の高周波電力配電体３２ｂにおける長さ寸法が等しく設定され、接続板Ｃ３２の接続面、つまり同一の接続面に接続される複数の高周波電力配電体３３ｂにおける長さ寸法が等しく設定され、接続板Ｃ３３の接続面、つまり同一の接続面に接続される複数の高周波電力配電体３４ｂにおける長さ寸法が等しく設定されることで、プラズマ励起電極４と接続板Ｃ３１〜Ｃ３３とのそれぞれ対向する接続面どうしを平行状態とすることができる。
【０１０７】
ここで、高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３が剛体からなり、作動中に高周波特性が変化するような変形をせず、取り外しおよび組み立てを伴うメンテナンス前後で変形せず、取り付け時における取り付け位置の再現性を有する。具体的には、上記の寸法の銅からなる棒状体または板状体とされ、ネジ等の結合手段によって上述の変形しない高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３が接続状態の正確性が再現性を有するように、相互に、および出力端子ＰＲ、プラズマ励起電極４と接続されているか、または、例えば溶接等により変形しないように接続されている。
【０１０８】
高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３の表面には、図５に示した第１実施形態の高周波電力配電体３１，３２ａおよび接続板Ｃ３１と同様に、Ｃｕからなる中心部に比べてＡｕ，Ａｇのような低抵抗材料からなる低抵抗部ＲＬが設けられ、この低抵抗部ＲＬの厚み寸法が、高周波電源１から供給される高周波電力周波数における表皮深さより大きく設定されている。
【０１０９】
さらに、高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３の表面には、第１実施形態の高周波電力配電体３１，３２ａおよび接続板Ｃ３１と同様に、絶縁体からなる絶縁被膜によって覆われてなる。
【０１１０】
上記構成のプラズマ処理装置９１は、ゲートｇ０を開放して被処理基板１６をロードロック室９３に搬入し、ゲートｇ０を閉塞してロードロック室９３を低真空ポンプによって排気する。ゲートｇ１，ｇ２を開放してロードロック室９３に搬入された基板１６を、搬送室９２の搬送ロボットの移載アームによって熱処理室９９に移動し、ゲートｇ１，ｇ２を閉塞して搬送室９２と熱処理室９９を高真空ポンプによって排気する。ついで基板１６を加熱処理し、終了後、ゲートｇ２，ｇ４を開放して熱処理された基板１６を、搬送室９２の搬送ロボットの移載アームによってプラズマチャンバ９５に移動する。プラズマチャンバ９５の基板１６を反応処理し、終了後ゲートｇ４，ｇ３を開放して処理された基板１６を、搬送室９２の搬送ロボットの移載アームによってプラズマチャンバ９６に移動する。プラズマチャンバ９６の基板１６を反応処理し、終了後ゲートｇ３，ｇ１を開放して基板１６を、搬送室９２の搬送ロボットの移載アームによってロードロック室９３に移動する。
【０１１１】
このとき、例えば各処理室における成膜条件等の処理条件や処理シーケンスをオペレータが設定する他は、各部の動作が制御部により制御されており、自動運転する構成になっている。したがって、このプラズマ処理装置９１を使用する際には、処理前の被処理基板１６をロードロック室９３のローダカセットにセットし、オペレータがスタートスイッチを操作すれば、基板搬送ロボットによりローダカセットから各処理室内に被処理基板１６が搬送され、各処理室で一連の処理が順次自動的に行われた後、基板搬送ロボットによりアンローダカセット（ローダカセット）に収容される。
【０１１２】
上記構成のプラズマチャンバ９５，９６においては、第１実施形態と同様に、サセプタ電極８上に被処理基板１６を載置し、高周波電源１，２７からそれぞれ高周波電極４とサセプタ電極８とに高周波電力を印加するとともにガス導入管１７からシャワープレート６を介して反応ガスをチャンバ室６０内に供給してプラズマを発生させ、被処理基板１６上にアモルファスシリコン膜、シリコン酸化膜、シリコン窒化膜等を成膜する。
【０１１３】
本実施形態のプラズマ処理装置９１においては、第１実施形態と同等の効果を奏することができるとともに、各プラズマチャンバ９５，９６の配電体部分（高周波電力配電体）３においては、接続板Ｃ３１〜Ｃ３３が多段に設けられて、出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電源１から供給される高周波電力の単位体積当たりの平均密度の最大値が粗になるよう設定されている、つまり、ｉ軸に垂直な板状の空間において、高周波電力配電体３１近傍における徴小な体積における高周波電力のエネルギー密度に比べて、高周波電力配電体３２ｂ近傍における徴小な体積における高周波電力のエネルギー密度が粗になっている。また、ｉ軸に垂直な板状の空間において、高周波電力配電体３２ｂ近傍における徴小な体積における高周波電力のエネルギー密度に比べて、高周波電力配電体３３ｂ近傍における微小な体積における高周波電力のエネルギー密度が粗になっている。さらに、ｉ軸に垂直な板状の空間において、高周波電力配電体３３ｂ近傍における徴小な体積における高周波電力のエネルギー密度に比べて、高周波電力配電体３４ｂ近傍における徴小な体積における高周波電力のエネルギー密度が粗になっている。
これにより、高周波電力配電体３における高周波電流の伝播する空間をより一層広げることができ、実質的にインダクタンスをさらに低減するとともに、高周波抵抗をさらに減少することができる。結果的に、配電体部分３における高周波電力の伝播する部分空間において、ｉ軸に垂直な板状の空間における徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分において接続板Ｃ３１一段の第１実施形態に比べて大きくなった３段の接続板Ｃ３１〜Ｃ３３の径方向寸法に対応してプラズマ励起電極４までの高周波電流に対する制限を低減することができる。同時に、高周波電力の伝播する部分空間において、微小な体積δＶにおけるエネルギー密度が減少することになり、接続板Ｃ３１一段の第１実施形態に比べて大きくなった３段の接続板Ｃ３１〜Ｃ３３の径方向寸法に対応してプラズマ励起電極４までの高周波抵抗が実質的に減少して、給電部分における電力ロスを低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力をより一層増大することが可能となる。
【０１１４】
その結果、本実施形態においては、同一周波数を供給した場合に、接続板Ｃ３１一段のプラズマ処理装置と比べてプラズマ空間で消費される実効的な電力の増大を図ることができ、膜の積層をおこなう際には、堆積速度の向上を図ることができるように、プラズマ処理結果の向上を図ることが可能となる。これにより、同一周波数を供給した場合に、接続板Ｃ３１が一段のプラズマ処理装置と比べてプラズマ空間で消費される実効的な電力のさらなる上昇を図ることができて、処理速度が一層向上する、例えば、プラズマＣＶＤ等により膜の積層をおこなう場合には堆積速度の向上をさらに図ることができる。また、プラズマ空間で消費される実効的な電力を変えずに、プラズマ励起周波数の高周波化により処理速度のさらなる向上を図ることができる。
【０１１５】
さらに、本実施形態においては、第１実施形態における接続板Ｃ３１一段の正三角形Ｔに対して、その寸法を大きく設定した正三角形Ｔ３の頂点に位置する高周波電力配電体３４ｂをプラズマ励起電極４に接続することで、接続板Ｃ３１一段の高周波電力配電体３２ａの間隔よりも広い高周波電力配電体３４ｂの間隔を有する給電点からプラズマ励起電極４に対して高周波電力を供給することができるため、より大きな径寸法を有するプラズマ励起電極４に対して、定在波が原因でプラズマ発生空間に発生するプラズマ密度に分布が生じてプラズマ処理に被処理基板面内方向への不均一が生じることが防止できて、より大きな径方向寸法を有する被処理基板１６に対して膜厚や膜質の基板面内での均一性が損なわれることを防止することができる。
【０１１６】
また、本実施形態においては、接続板Ｃ３１〜Ｃ３３の異なる接続面つまり表側面と裏側面とに接続される複数の高周波電力配電体３２ｂ〜３４ｂにおける径寸法および断面形状、長さ寸法もいずれも等しく設定されることにより、複数段に高周波電力配電体３１，３２ｂ〜３４ｂおよび接続板Ｃ３１〜Ｃ３３が接続される際に、各段における高周波特性の設定を容易にすることが可能となる。
【０１１７】
なお、本実施形態においては、各段における高周波電力配電体３２ｂ〜３４ｂを接続板Ｃ３１〜Ｃ３３に接続する際に、図１９に示すように正三角形Ｔ１〜Ｔ３をそれぞれ同一の方向に接続したが、図２０に示すように、正三角形Ｔ１＝Ｔ３の中心がいずれも電極中心４０と重なるようにかつ、それぞれの角度が一致しないように接続することも可能である。
また、２段目の接続板Ｃ３２の表側面に接続される高周波電力配電体３２ｂの接続状態と、３段目の接続板Ｃ３３の表側面とに接続される高周波電力配電体３３ｂの接続状態とを、異なるものにすることができる。例えば、図２１に示すように、高周波電力配電体３２ｂを正三角形Ｔ１の頂点に配置し、高周波電力配電体３３ｂを正六角形Ｓ２の頂点に配置することも可能である。
【０１１８】
さらに、平行平板型の電極４，８を有するタイプに変えて、ＩＣＰ（inductive coupled plasma）誘導結合プラズマ励起型、ＲＬＳＡ（radial line slot antenna）ラジアルラインスロットアンテナ型などのプラズマ処理装置や、ＲＩＥ（Riactive Ion Etching）反応性スパッタエッチング用の処理装置に適用することもできる。
なお、電極４，８に替えて、ターゲット材を取り付けることにより、プラズマ処理としてスパッタリングをおこなうことも可能である。
【０１１９】
以下、本発明に係るプラズマ処理装置およびプラズマ処理システムの第３実施形態を、図面に基づいて説明する。
［第３実施形態］
図２２は本実施形態のプラズマチャンバの概略構成を示す模式図である。
【０１２０】
本実施形態のプラズマ処理装置は、図１〜図１５に示した第１実施形態と略同等の構成とされ、図１〜図１５に示した第１実施形態と異なる点は、プラズマ処理室ユニット（プラズマチャンバ）におけるチャンバとマッチングボックスの位置関係、および、配電体部分３に関する点のみであり、プラズマ処理装置としての構成に関しては第１実施形態に準ずるものとされる。また、これ以外の第１実施形態と略同等の構成要素に関しては同一の符号を付してその説明を省略する。
【０１２１】
本実施形態においても、プラズマチャンバ７５を例に挙げてその構成を説明する。
プラズマチャンバ７５は、チャンバ室（プラズマ処理室）６０の上部位置に高周波電源１に接続されたプラズマ励起電極（電極）４およびシャワープレート５が設けられ、プラズマ励起電極４はチャンバ壁１０に接続されたシャーシ２１に覆われているが、整合回路２Ａおよび、整合回路２Ａの収容されるマッチングボックス２は、チャンバ室６０の上部位置から離間した位置に設けられている。
【０１２２】
プラズマ励起電極４と整合回路２Ａの出力端子ＰＲとは、配電体部分３で接続されるとともに、この配電体部分（高周波電力配電体）３は、出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電源１から供給される高周波電力の単位体積当たりの平均密度の最大値が粗になるよう設定されており、本実施形態における配電体部分３は、導体からなるハウジング（遮蔽導体）２１Ａの内部に収納されている、
【０１２３】
このハウジング２１Ａは、シャーシ（遮蔽導体）２１およびマッチングボックス（遮蔽導体）２に接続されるとともに、マッチングボックス２は同軸ケーブルとされる給電線１Ａのシールド線（外導体）に接続されており、このシールド線が直流的にアースされている。これにより、サセプタ電極８，シャフト１３，ベローズ１１，チャンバ底部１０Ａ，チャンバ壁１０，シャーシ２１，ハウジング２１Ａ，マッチングボックス２は接地電位に設定されることになり、同時に、ロードコンデンサ２２の一端も直流的にアースされた状態となる。
これら、チャンバ壁１０、ハウジング２１Ａ、シャーシ２１、マッチングボックス２、給電線１Ａのシールド線、はそれぞれ、高周波電源１から供給された高周波電流ｉが高周波電源１側に戻る経路、つまり、電流経路の復路を構成しているものである。
【０１２４】
このハウジング２１Ａは、特に配電体部分３から外部への不要輻射を遮断するように、配電体部分３を覆うように設けられるとともに、シャーシ２１およびマッチングボックス２に設けられた配電体部分３接続用の穴を覆うように設けられている。
【０１２５】
本実施形態のプラズマチャンバ７５は、配電体部分３において、高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”が複数の接続体Ｃ３１，Ｃ３２’によって互いに接続され前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１から前記電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定された構成とされている。
具体的に配電体部分３では、図２２に示すように、等しい断面円形状で経寸法２〜１０ｍｍ、および、異なる長さ寸法１００〜３００ｍｍの形状を有する棒状の銅からなる高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”が接続板（接続体）Ｃ３１に接続され、また、等しい断面円形状で経寸法２〜１０ｍｍ、および、異なる長さ寸法１００〜３００ｍｍの形状を有する棒状の銅からなる高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”が、接続体Ｃ３２’に接続されている。これら高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’は剛体とされている。
【０１２６】
接続板Ｃ３１は、プラズマ励起電極４より小さく相似状態の銅からなる円板とされ、かつ、接続板Ｃ３２’は、接続板Ｃ３１と同じ厚さの銅板でプラズマ励起電極４より小さくこのプラズマ励起電極４の輪郭を軸線Ｌに対して４５°の角度で交わる面に対して投射した射影図となる楕円形の輪郭と相似状態の輪郭形状を有するものとされる。また、接続板Ｃ３１は、プラズマ励起電極４と直交状態に配置され、接続板Ｃ３２’はプラズマ励起電極４および接続板Ｃ３１に対して４５°を為すように配置されている。これら接続体Ｃ３１，Ｃ３２’は整合回路２Ａの出力端子ＰＲ側からプラズマ励起電極４側までの間に、接続板Ｃ３１、接続板Ｃ３２’の順に輪郭形状の径方向寸法が大きくなるよう多段に設けられている。
【０１２７】
ここで、配電体部分３で出力端子ＰＲから電極４までの電流の伝播方向であるｉ軸としては、接続板Ｃ３２’よりも出力端子ＰＲ側では接続板Ｃ３１に垂直な方向に設定し、接続板Ｃ３２’よりもプラズマ励起電極４側ではプラズマ励起電極４に垂直な方向に設定する。これにより、接続板Ｃ３１，Ｃ３２’における電流伝播経路に沿った方向（ｉ軸方向）から見た輪郭形状がそれぞれプラズマ励起電極４と相似状態になる。
【０１２８】
高周波電力配電体３１の一端は、整合回路２Ａの出力端子ＰＲとされるチューニングコンデンサ２４の出力端子にネジ止めなどの結合手段により着脱可能に取り付けられており、高周波電力配電体３１の他端は接続板（接続体）Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）に直交しかつこの接続板Ｃ３１の中心Ｃ３０位置に接続されている。
【０１２９】
そして、接続板Ｃ３１の裏側面（プラズマ励起電極４側面）にはこの裏側面と直交するように複数の高周波電力配電体３２ｃ，３２ｃ’．３２ｃ”がその一端で接続され、これら高周波電力配電体３２ｃ，３２ｃ’．３２ｃ”の他端が接続板Ｃ３２’の表側面（整合回路２Ａの出力端子ＰＲ側面）に４５°を為して接続されている。接続板Ｃ３２’の裏側面（プラズマ励起電極４側面）には複数の高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”の一端が接続板Ｃ３２’の裏側面と４５°を為してかつ高周波電力配電体３２ｃ，３２ｃ’．３２ｃ”と直交して接続され、これら高周波電力配電体３３ｃ，３３ｃ’．３３ｃ”の他端がプラズマ励起電極４表面に直交して接続されている。これら高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”は、いずれもプラズマ励起電極４と直交する方向とされる出力端子ＰＲからプラズマ励起電極４までの電流の伝播方向のｉ軸と平行に設けられている。
【０１３０】
本実施形態の高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”において、前記出力端子ＰＲ側から前記電極４側に向かって前記高周波電源１からプラズマ励起電極４まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定されてなる。言い換えると、チューニングコンデンサ２４の出力端子ＰＲに取り付けられた一本の高周波電力配電体３１の一端から、プラズマ励起電極４表面に接続された複数本の高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”の他端にむかって、高周波電力配電体３１，３３ｃ，３３ｃ’，３３ｃ”における高周波電流の伝播する空間が広がり、実質的にインダクタンスが低減されるとともに、かつ、高周波抵抗が減少されるようになっている。
具体的には、配電体部分３の一段目においては、出力端子ＰＲ側が一本の高周波電力配電体３１、接続板Ｃ３１の裏側面側が３本の高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”とされて、高周波電流の伝播する空間が約３倍になっている。また、配電体部分３の２段目においては、接続板Ｃ３２’の表側面の高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”どうしの間隔よりも接続板Ｃ３２’の裏側面の高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”どうしの間隔が大きく設定されて高周波電流の伝播する空間が広がっている。
【０１３１】
ここで、１本の高周波電力配電体３１は、接続板Ｃ３１の表側面（整合回路２Ａの出力端子ＰＲ側面）において、その中心Ｃ３０位置に接続されており、かつこの中心Ｃ３０を通り接続板Ｃ３１の表側面に垂直な軸線Ｌ’と平行状態、つまりこの軸線Ｌ’と一致して設けられている。
３本の高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”は、互いに平行状態とされて、かつ、円形の接続板Ｃ３１の中心Ｃ３０に対して軸対称な状態で接続板Ｃ３１の裏側面（プラズマ励起電極４側面）および接続板Ｃ３２の表側面（整合回路２Ａの出力端子ＰＲ側面）に接続されている。ここで、軸対称とは、接続板Ｃ３１の中心Ｃ３０を通り、接続板Ｃ３１面に垂直な軸線Ｌ’に対して空間的に対称なこと、つまり、それぞれの高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”は、図１９に示した第２実施形態のように、接続板Ｃ３１における正三角形Ｔ１の頂点に位置し、この正三角形Ｔ１の中心，接続板Ｃ３１の中心Ｃ３０，接続板Ｃ３２の中心Ｃ３０，とがそれぞれ一致するように接続位置を設定している。
【０１３２】
また、３本の高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”は、互いに平行状態かつ、プラズマ励起電極４の中心４０を通りプラズマ励起電極４に垂直な軸線Ｌに対して平行とされて、円形のプラズマ励起電極４の中心４０に対して軸対称な状態で接続板Ｃ３２’の裏側面およびプラズマ励起電極４面に接続されている。ここで、軸対称とは、電極中心４０を通り、プラズマ励起電極４面に垂直な軸線Ｌに対して空間的に対称なこと、つまり、それぞれの高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”は、図１９に示した第２実施形態に対応して、プラズマ励起電極４における正三角形Ｔ２の頂点に位置し、この正三角形Ｔ２の中心，電極中心４０および，接続板Ｃ３２’の中心Ｃ３０がそれぞれ一致するように接続位置を設定している。
ここで、軸線Ｌと軸線Ｌ’とは、接続板Ｃ３２’の中心Ｃ３０で交わるとともに、互いに直交している。
【０１３３】
ここで、接続板Ｃ３２’の表面と裏面とで、それぞれ相似状態となるように高周波電力配電体３２ｃ，３２ｃ’，３２ｃ”と高周波電力配電体３３ｃ，３３ｃ’，３３ｃ”が接続されている、つまり、接続板Ｃ３１およびプラズマ励起電極４における高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”の接続位置を示す正三角形Ｔ１，Ｔ２が相似状態かつその方向も等しく（頂点の方向が一致した状態と）なるように設定されている。
【０１３４】
ここで、高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’が剛体からなり、作動中に高周波特性が変化するような変形をせず、取り外しおよび組み立てを伴うメンテナンス前後で変形せず、取り付け時における取り付け位置の再現性を有する。具体的には、上記の寸法の銅からなる棒状体または板状体とされ、ネジ等の結合手段によって上述の変形しない高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’が接続状態の正確性が再現性を有するように、相互に、および出力端子ＰＲ、プラズマ励起電極４と接続されているか、または、例えば溶接等により変形しないように接続されている。
【０１３５】
高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’の表面には、図５に示した第１実施形態の高周波電力配電体３１，３２ａおよび接続板Ｃ３１と同様に、Ｃｕからなる中心部に比べてＡｕ，Ａｇのような低抵抗材料からなる低抵抗部ＲＬが設けられ、この低抵抗部ＲＬの厚み寸法が、高周波電源１から供給される高周波電力周波数における表皮深さより大きく設定されている。
【０１３６】
さらに、高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’の表面には、第１実施形態の高周波電力配電体３１，３２ａおよび接続板Ｃ３１と同様に、絶縁体からなる絶縁被膜によって覆われてなる。
【０１３７】
本実施形態のプラズマ処理装置７１においては、第１，第２実施形態と同等の効果を奏するとともに、各プラズマチャンバ７５，７６，７７の配電体部分（高周波電力配電体）３においては、高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”および接続板Ｃ３１，Ｃ３２’が、チャンバ室６０のチャンバ壁１０に接続される遮蔽導体としてのハウジング２１Ａ，シャーシ２１およびマッチングボックス２に覆われてこれらの内部に収容されること、つまり、高周波電源１から供給された高周波電流経路の復路を構成している遮蔽導体内部に配電体部分３が位置することにより、整合回路２Ａの設置場所の自由度を損なうことなく、同軸ケーブルのように外部への不要輻射を遮断できて、配電体部分３における高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限を低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスを低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力を増大することが可能となる、つまり、整合回路２Ａとプラズマ励起電極４とチャンバ室６０との位置関係に関わりなく、給電部分の遮蔽をおこなうことが可能となる。
【０１３８】
なお、本実施形態の配電体部分３において、接続板Ｃ３１，Ｃ３２’が、２段からなるものとしたが、より多段にすること、および、接続板Ｃ３２’の一段のみで構成することも可能である。さらに、この配電体部分３が概略Ｌ字状とされる以外にもコ字状やそれ以外の形状に構成されることも可能である。
さらに、接続板Ｃ３２’と高周波電力配電体３１，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”とを４５°を為すように構成したがこれも任意の角度を為すようにすることができる。
【０１３９】
なお、本実施形態の配電体部分３を、図１７に示した第２実施形態における給電板２８に替えて適用することが可能である。
さらに、平行平板型の電極４，８を有するタイプに変えて、ＩＣＰ（inductive coupled plasma）誘導結合プラズマ励起型、ＲＬＳＡ（radial line slot antenna）ラジアルラインスロットアンテナ型などのプラズマ処理装置や、ＲＩＥ（Riactive Ion Etching）反応性スパッタエッチング用の処理装置に適用することもできる。
【０１４０】
さらに、上記の各実施形態におけるプラズマ処理装置においては、プラズマ処理室ユニット（プラズマチャンバ）を複数有する構成としたが単数からなる構成とすることも可能である。
【０１４１】
以下、本発明に係るプラズマ処理装置およびプラズマ処理システムの第４実施形態を、図面に基づいて説明する。
［第４実施形態］
図２３は本実施形態のプラズマ処理システムの概略構成を示す模式図である。
【０１４２】
本実施形態のプラズマ処理システムは、図１に示した第１，第３実施形態と略同等のプラズマ処理装置７１，７１’と、図１６に示した第２実施形態と略同等のプラズマ処理装置９１と、を組み合わせて概略構成されている。先に説明した第１ないし第４実施形態の構成要素に対応するものには同一の符号を付してその説明を省略する。
【０１４３】
本実施形態のプラズマ処理システムは、図２３に示すように、３つのプラズマ処理室ユニット（プラズマチャンバ）９５，９６，９７を有するプラズマ処理装置７１、２つのプラズマ処理室ユニット（プラズマチャンバ）９５，９６を有するプラズマ処理装置９１、および、３つのプラズマ処理室ユニット（プラズマチャンバ）９５，９６，９７を有するプラズマ処理装置７１’が製造ラインの一部を構成するものとされている。
ここで、図１に示したような第１，第３実施形態のプラズマ処理装置７１，７１’の部分において、プラズマ処理室ユニット（プラズマチャンバ）７５，７６，７７に替えて、図１６に示した第２実施形態における２周波数励起タイプのプラズマ処理室ユニット（プラズマチャンバ）９５と略同等のプラズマ処理室ユニットを３つ有する構成とされており、これらプラズマ処理室ユニット（プラズマチャンバ）９５，９６，９７は略同一の構造とされている。
【０１４４】
本実施形態のプラズマ処理システムは、図２３に示すように、各プラズマチャンバ９５，９６，９７に対するインピーダンス測定用端子がスイッチＳＷ３を介してインピーダンス測定器ＡＮに接続されている。スイッチＳＷ３は各プラズマチャンバ９５，９６，９７の測定時に測定対象のプラズマチャンバ９５，９６，９７とインピーダンス測定器ＡＮとのみを接続して、それ以外のプラズマチャンバ９５，９６，９７を切断するよう切り替えるスイッチとして設けられている。
【０１４５】
本実施形態において、複数のプラズマチャンバ９５，９６，９７のプラズマ励起電極４と整合回路２Ａの出力端子ＰＲとは、配電体部分３で接続されるとともに、この配電体部分（高周波電力配電体）３は、出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電源１から供給される高周波電力の単位体積当たりの平均密度の最大値が粗になるよう設定されており、本実施形態における配電体部分３は、導体からなるハウジング（遮蔽導体）２１Ａおよび／またはシャーシ２１、マッチングボックス２に覆われてこれらの内部に収容されている。
【０１４６】
本実施形態のプラズマ処理システムにおいては、例えば、プラズマ処理前処理をおこなった被処理基板１６に、プラズマ処理装置７１のプラズマチャンバ９５，９６，９７において成膜処理をおこない、ついで、熱処理室７９において加熱処理をおこない、その後、レーザーアニール室７８においてアニール処理をおこなう。次いで、この被処理基板１６をプラズマ処理装置７１から搬出し、図示しないプラズマ処理装置７１と同等の装置におけるプラズマ処理室において、被処理基板１６に順次第２，第３の成膜処理をおこなう。
次いで、このプラズマ処理装置から搬出した被処理基板１６に、図示しない別の処理装置において、フォトリソグラフィー工程によりフォトレジストの形成をおこなう。
そして、被処理基板１６をプラズマ処理装置９１に搬入し、プラズマチャンバ９５，９６においてプラズマエッチングをおこなう。
次いで、図示しないプラズマ処理装置から搬出された被処理基板１６に、図示しない他の処理装置において、レジストを剥離する。
最後に、プラズマ処理装置７１’のプラズマチャンバ９５、９６，９７において被処理基板１６に順次第１，第２，第３の成膜処理がおこなわれ、被処理基板１６をプラズマ処理後処理へと送り、製造ラインにおける本実施形態のプラズマ処理システムにおける工程は終了する。
【０１４７】
本実施形態のプラズマ処理システムにおいては、第１〜第３実施形態と同等の効果を奏するとともに、プラズマチャンバ９５，９６，９７のプラズマ励起電極４と整合回路２Ａの出力端子ＰＲとは、それぞれ配電体部分３で接続されるとともに、この配電体部分（高周波電力配電体）３は、出力端子ＰＲ側からプラズマ励起電極４側に向かって高周波電源１から供給される高周波電力の単位体積当たりの平均密度の最大値が粗になるよう設定されているため、各プラズマチャンバ９５，９６，９７において、高周波電力の伝播する部分空間におけるエネルギー密度をより減少し、実質的にインダクタンスを低減して、高周波抵抗がさらに減少し、高周波電源１からプラズマ励起電極４に至る給電部分における高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的にインダクタンスが低減して、給電部分における高周波電流に対する制限をいっそう低減することができる。同時に、高周波電力の伝播する部分空間において、徴小な体積δＶにおけるエネルギー密度が減少することになり、実質的に高周波抵抗が減少して、給電部分における電力ロスをさらに低減することができる。
その結果、プラズマ発生空間で消費される実効的な高周波電力を増大することが可能となるとともに、複数のプラズマチャンバ９５，９６，９７において高周波電力のロスを低減できることにより、プラズマ処理システム全体としての高周波電力のロスをより一層低減することが可能となる。
【０１４８】
また、それぞれのプラズマチャンバ９５，９６，９７に対する電気的高周波的な特性の機差を低減することが可能となり、これにより、プラズマ処理システム全体においてインピーダンス特性を指標とする一定の管理幅内に複数のプラズマチャンバ９５，９６，９７の状態を設定することが可能となるので、個々のプラズマチャンバ９５，９６，９７において、発生するプラズマ密度等をそれぞれ略均一にすることができる。これにより、プラズマ処理システム全体において複数のプラズマチャンバ９５，９６，９７に対して同一のプロセスレシピを適用して、略同一のプラズマ処理結果を得ること、つまり、複数のプラズマチャンバ９５，９６，９７において例えば成膜をおこなった際に、膜厚、絶縁耐圧、エッチングレート等、略均一な膜特性の膜を得ることが可能となる。そのため、プラズマ処理システムの全般的な電気的高周波的特性を設定することにより、個々のプラズマチャンバ９５，９６，９７におけるプラズマ発生の安定性を期待することができる。その結果、動作安定性が高く、各プラズマチャンバ９５，９６，９７で均一な動作が期待できるプラズマ処理システムを提供することが可能となる。
【０１４９】
また、同一周波数を供給した場合に、従来のプラズマ処理システムと比べてプラズマ空間で消費される実効的な電力の向上を図ることができるため、プラズマ処理システム全体として電力の消費効率を向上し、同等の処理速度もしくは膜特性を得るために、従来より少ない投入電力ですむようにできる。しかも、これらを、複数のプラズマチャンバ９５，９６，９７において実現することができる。したがって、プラズマ処理システム全体の電力損失の低減を図ること、ランニングコストの削減を図ること、生産性の向上を図ることがより一層可能になる。同時に、処理時間をより短縮することが可能となるため、プラズマ処理に要する電力消費を減らせることから環境負荷となる二酸化炭素の総量をより削減することが可能となる。
【０１５０】
さらに、平行平板型の電極４，８を有するタイプに変えて、ＩＣＰ（inductive coupled plasma）誘導結合プラズマ励起型、ＲＬＳＡ（radial line slot antenna）ラジアルラインスロットアンテナ型などのプラズマ処理装置や、ＲＩＥ（Riactive Ion Etching）反応性スパッタエッチング用の処理装置に適用することもできる。
【０１５１】
【発明の効果】
本発明のプラズマ処理装置およびプラズマ処理システムによれば、前記高周波電力配電体において、前記出力端子側から前記電極側に向かって前記高周波電源から前記電極まで供給される高周波電力の単位体積当たりの平均密度が粗になるよう設定されてなることにより、高周波電力配電体における高周波電流の伝播する空間が広がり、実質的に高周波抵抗を減少するとともにインダクタンスを低減して、プラズマ発生空間に供給される高周波電力のロスを低減することが可能となるという効果を奏することができる。
【図面の簡単な説明】
【図１】 本発明に係るプラズマ処理装置の第１実施形態における概略構成を示す図である。
【図２】 本発明に係るプラズマ処理装置の第１実施形態におけるプラズマ処理室ユニット（プラズマチャンバ）の概略構成を示す断面図である。
【図３】 図２におけるプラズマ処理室ユニット（プラズマチャンバ）の配電体部分３を示す斜視図である。
【図４】 図２の配電体部分３およびプラズマ励起電極４を示す平面図である。
【図５】 高周波電力配電体３１，３２ａおよび接続板Ｃ３１の低抵抗部ＲＬおよび表皮深さδを説明するための断面図である。
【図６】 図１におけるレーザアニール室を示す縦断面図である。
【図７】 図１における熱処理室を示す縦断面図である。
【図８】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図９】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１０】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１１】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１２】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１３】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１４】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１５】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図１６】 本発明に係るプラズマ処理装置の第２実施形態を示す概略構成図である。
【図１７】 本発明に係るプラズマ処理装置の第２実施形態におけるプラズマ処理室ユニット（プラズマチャンバ）の概略構成を示す断面図である。
【図１８】 図１７におけるプラズマ処理室ユニット（プラズマチャンバ）の配電体部分３を示す正面図である。
【図１９】 図１７の配電体部分３およびプラズマ励起電極４を示す平面図である。
【図２０】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図２１】 本発明にかかる高周波電力配電体および接続板の他の実施形態を示す平面図である。
【図２２】 本発明に係るプラズマ処理装置の第３実施形態におけるプラズマ処理室ユニット（プラズマチャンバ）の概略構成を示す断面図である。
【図２３】 本発明に係るプラズマ処理システムの第４実施形態における概略構成を示す模式図である。
【図２４】 本発明における高周波電力の伝播状態を説明するための斜視図および電力エネルギー密度を示す模式グラフである。
【図２５】 本発明における高周波電力の伝播状態を説明するための斜視図および電力エネルギー密度を示す模式グラフである。
【図２６】 従来のプラズマ処理装置の一例を示す模式図である。
【図２７】 従来のプラズマ処理装置の他の例を示す模式図である。
【図２８】 本発明にかかる実施形態において配電体部分における低抵抗部を部分的に設けた構成を示す正面図である。
【図２９】 本発明にかかる実施形態において配電体部分における低抵抗部を部分的に設けた構成を示す正面図である。
【符号の説明】
１…高周波電源
１Ａ，２７Ａ…給電線（高周波電力給電体）
２…マッチングボックス（遮蔽導体）
２Ａ，２５…整合回路
３…配電体部分（高周波電力配電体）
Ｃ３１〜Ｃ３３，Ｃ３２’…接続板（接続体）
４…プラズマ励起電極（カソード電極）
５…シャワープレート
６…空間
７…孔
８…ウエハサセプタ（サセプタ電極）
９…絶縁体
１０…チャンバ壁
１０Ａ…チャンバ底部
１１…ベローズ
１２…サセプタシールド
１２Ａ…シールド支持板
１２Ｂ…支持筒
１３…シャフト
１６…基板（被処理基板）
１７…ガス導入管
１７ａ…絶縁体
２１…シャーシ（遮蔽導体）
２１Ａ…ハウジング（遮蔽導体）
２２，３２…ロードコンデンサ
２３，３０…チューニングコイル
２４，３１…チューニングコンデンサ
２６…マッチングボックス
２７…第２の高周波電源
２８…給電板（高周波電力配電体）
２９…シャーシ
３１，３２ａ，３２ｂ〜３４ｂ，３２ｃ，３２ｃ’，３２ｃ”，３３ｃ，３３ｃ’，３３ｃ”…高周波電力配電体
６０…チャンバ室（プラズマ処理室）
７１，９１…プラズマ処理装置
７２，９２…搬送室
７３…ローダ室
７４…アンローダ室
７５、７６，７７，９５，９６，９７…プラズマチャンバ（プラズマ処理室ユニット）
７８…レーザアニール室
７９，９９…熱処理室
８０，８４…チャンバ
８１…レーザ光源
８２…ステージ
８３…レーザ光
８５…ヒータ
８６…ゲートバルブ
８７…基板搬送ロボット（搬送手段）
８８…アーム
９３…ロードロック室[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plasma processing apparatus and a plasma processing system, and more particularly to a technique suitable for use in reducing power loss in response to high-frequency power supply.
[0002]
[Prior art]
As an example of a plasma processing apparatus for performing plasma processing such as chemical vapor deposition (CVD), sputtering, dry etching, and ashing, a so-called two-frequency excitation type as shown in FIG. 27 is conventionally known.
In the plasma processing apparatus shown in FIG. 27, a matching circuit 2 </ b> A is interposed between the high-frequency power source 1 and the plasma excitation electrode 4. The matching circuit 2A is provided as a circuit for obtaining impedance matching between the high frequency power source 1 and the plasma excitation electrode 4.
[0003]
The high frequency power from the high frequency power source 1 is supplied to the plasma excitation electrode 4 by the power supply plate (distributor) 3 through the matching circuit 2A. The matching circuit 2A is housed in a matching box 2 formed by a housing made of a conductor, and the plasma excitation electrode 4 and the power feeding plate 3 are covered with a chassis 21 made of a conductor. An annular convex portion 4a is provided below the plasma excitation electrode (cathode electrode) 4, and a shower plate 5 in which a large number of holes 7 are formed is provided in contact with the convex portion 4a. A space 6 is formed between the plasma excitation electrode 4 and the shower plate 5. A gas introduction pipe 17 is connected to the space 6, and an insulator 17 a is inserted in the middle of the gas introduction pipe 17 made of a conductor to insulate the plasma excitation electrode 4 side from the gas supply source side.
[0004]
The gas introduced from the gas introduction pipe 17 is supplied into the chamber chamber 60 formed by the chamber wall 10 through the hole 7 of the shower plate 5. Reference numeral 9 denotes an insulator that insulates the chamber wall 10 from the plasma excitation electrode (cathode electrode) 4. The exhaust system is not shown.
On the other hand, a wafer susceptor (susceptor electrode) 8 on which a substrate 16 is placed and also serves as a plasma excitation electrode is provided in the chamber chamber 60, and a susceptor shield 12 is provided around the wafer susceptor.
[0005]
The susceptor shield 12 includes a shield support plate 12A that receives the susceptor electrode 8, and a cylindrical support tube 12B that is suspended from the center of the shield support plate 12A. The support tube 12B is provided through the chamber bottom 10A. In addition, the lower end portion of the support cylinder 12B and the chamber bottom portion 10A are hermetically connected by the bellows 11.
The wafer susceptor 8 and the susceptor shield 12 are vacuum-insulated and electrically insulated by an insulating means 12 </ b> C made of an electrical insulator provided around the shaft 13. Further, the wafer susceptor 8 and the susceptor shield 12 can be moved up and down by the bellows 11, and the distance between the plasma excitation electrodes 4 and 8 can be adjusted.
A second high frequency power supply 15 is connected to the wafer susceptor 8 via a matching circuit housed in the shaft 13 and the matching box 14. The chamber wall 10 and the susceptor shield 12 are at the same potential in terms of DC.
[0006]
FIG. 26 shows another example of a conventional plasma processing apparatus. Unlike the plasma processing apparatus shown in FIG. 27, the plasma processing apparatus shown in FIG. 26 is a one-frequency excitation type plasma processing apparatus. That is, high-frequency power is supplied only to the cathode electrode 4, and the susceptor electrode 8 is grounded. The high frequency power supply 15 and the matching box 14 shown in FIG. 27 are omitted. Further, the susceptor electrode 8 and the chamber wall 10 are at the same potential in terms of DC.
[0007]
In the above plasma processing apparatus, generally, electric power having a frequency of about 13.56 MHz is applied to generate plasma between both electrodes 4 and 8, and by this plasma, CVD (chemical vapor deposition), sputtering, Plasma processing such as dry etching and ashing is performed.
[0008]
[Problems to be solved by the invention]
However, in the conventional plasma processing apparatus, the inductance in the power distribution portion near the power supply plate 3 is large, and this restricts the high-frequency current flowing into the plasma generation space between the electrodes 4 and 8, so that it is input to the plasma space. There has been a problem that the generated plasma density may be reduced by reducing the generated power.
In addition, there is a problem that the power supply loss in the high frequency resistance component of the power supply plate 3 is large and the high frequency power that is effectively consumed in the plasma generation space is small.
Furthermore, the power supply plate 3 is not necessarily connected to the center of the electrode 4, which may cause a drift in the high-frequency current, resulting in a density distribution in the direction of the electrode surface of the plasma generation density, and the result of plasma processing on the substrate There is a problem that the film thickness and other film characteristics may vary in the in-plane direction.
Further, when the size of the electrode 4 (here, the longest distance from the feeding center to the periphery of the electrode) is larger than the quarter wavelength of the plasma excitation frequency, the standing wave becomes a problem. That is, there is a problem that the plasma density is distributed and the uniformity of the film thickness and film quality within the substrate surface is impaired.
[0009]
In particular, the above-described variation in plasma treatment in the in-plane direction is notable and cannot be ignored when the input power is about 150 MHz and the diameters of the electrodes 4 and 8 are about 60 cm, that is, the substrate to be processed has a diameter of about 50 cm. There was a problem.
In particular, in an apparatus that performs a process for a liquid crystal display substrate, the size of the substrate is increasing, and this problem is more conspicuous as compared with a semiconductor manufacturing apparatus.
[0010]
In addition, the above-described variations in plasma processing may also occur due to changes in the plasma processing apparatus over time as the processing progresses. In particular, the fluctuation factors of changes in plasma processing over time caused by the power supply plate 3 are suppressed. However, there has been a demand to perform uniform and stable plasma processing over time. In particular, when performing plasma processing a plurality of times, there is a problem that the high frequency characteristics of the power feeding portion change each time the plasma processing is repeated, and the respective plasma processing results are not stable.
This is because, for example, when the power supply plate 3 made of a copper plate is connected to the tuning capacitor output terminal of the matching circuit 2A and the electrode 4, the shape thereof can be changed, that is, deformation before and after the plasma treatment, This was conspicuous when deformation before and after maintenance was possible, or when the power supply plate 3 was oxidized.
[0011]
Furthermore, for plasma processing systems having a plurality of plasma processing apparatuses as described above, there is also a demand for reducing the difference in plasma processing between the individual plasma chambers in each plasma processing apparatus. It was.
Furthermore, since there are few installation position freedom degrees of the electric power feeding part from the matching circuit 2 to the electrode 4, there existed a request | requirement of improving this, without reducing a high frequency characteristic.
[0012]
The present invention has been made in view of the above circumstances, and intends to achieve the following object.
1. To reduce inductance in the power feeding part.
2. Reduce high frequency resistance.
3. Reduce power supply loss.
4). Prevent the drift of high-frequency current.
5). To reduce variations in the in-plane direction of plasma treatment.
6). Suppress changes in inductance over time in the power feeding section.
7). Suppress fluctuations in high-frequency resistance in the power feeding section.
8). To improve the uniformity of power supply to the plasma generation space.
9. To improve the stability of the plasma generation state.
10. To improve stability in multiple plasma treatments.
11. Improve the degree of freedom of installation of the matching circuit.
[0013]
[Means for Solving the Problems]
  The plasma processing apparatus of the present invention includes a plasma processing chamber having an electrode for exciting plasma,
  A high frequency power source for supplying high frequency power to the electrode;
  An input terminal and an output terminal, the high-frequency power source is connected to the input terminal via a high-frequency power feeder, and the electrode is connected to the output terminal via a high-frequency power distributor; A plasma processing chamber unit having a matching circuit for obtaining impedance matching with a high-frequency power source,
  In the high frequency power distribution body, the average density per unit volume of the high frequency power supplied from the high frequency power source to the electrode from the output terminal side toward the electrode side is set to be coarse.,
The high-frequency power distribution body consists of a plurality of wires,
The plurality of high-frequency power distribution bodies are provided in parallel with each other,
The plurality of high-frequency power distribution bodies are connected to the electrodes in an axially symmetric state with respect to the center of the electrodes;
The plurality of high-frequency power distribution bodies are connected to each other by a connection body,
The connection body is provided with a surface substantially parallel to the electrode.The above-mentioned problem was solved by becoming.
Further, the connection body may be a plate-like body having a shape similar to that of the electrode.
  Further, the plurality of high-frequency power distribution bodies can be connected to the connection body in an axially symmetric state with respect to the center of the connection body.
  In the present invention, it is preferable that the plurality of high-frequency power distribution bodies are connected so that the front surface and the back surface of the connection body are in a similar state.
  In the present invention, a plurality of the connection bodies may be provided from the output terminal side to the electrodes.
  In the present invention, in the plurality of high-frequency power distribution bodies, the high-frequency characteristics of the high-frequency power distribution bodies can be set to be equal to each other.
  In the present invention, it is more preferable that a low resistance portion made of a low resistance material is provided on the surface of the high frequency power distribution body as compared with the central portion.
  In the present invention, the surface of the connection body may be provided with a low resistance portion made of a low resistance material compared to the center portion.
  In the present invention, it is also possible to adopt means in which the thickness dimension of the low resistance portion is set larger than the skin depth at the high frequency power frequency supplied from the high frequency power source.
  Further, the surface of the high-frequency power distributor may be covered with an insulating film made of an insulator.
  In the present invention, the surface of the connection body may be covered with an insulating film made of an insulator.
  Furthermore, the high frequency power distribution body may be made of a rigid body.
  Moreover, it is desirable that the connection body is made of a rigid body.
  In the present invention, the high-frequency power distributor can be accommodated in a shielding conductor connected to a chamber wall of the plasma processing chamber.
  In the present invention, the connection body may be accommodated in a shielding conductor connected to a chamber wall of the plasma processing chamber.
  In the plasma processing apparatus of the present invention, in each of the plasma processing apparatuses described above,
  It is preferable that a plurality of the plasma processing chamber units are provided.
  In the plasma processing system of the present invention, a means in which a plurality of the plasma processing apparatuses described above are provided may be employed.
In the present invention, the plurality of connectors are radially dimensioned from the output terminal side toward the electrode side. It is possible to be provided in multiple stages so that the law becomes large.
The present invention provides the plurality of connectors,The plurality of high frequency power distribution bodiesCan be provided in multiple stages so that the area of the polygon with the apex increases from the output terminal side toward the electrode side.
In the present invention, the current propagation direction in the high-frequency power distribution part connected to the electrode is set in a direction perpendicular to the current propagation direction in the high-frequency power distribution part connected to the output terminal. It is possible.
[0014]
In the plasma processing apparatus of the present invention, in the high frequency power distribution body, an average density per unit volume of the high frequency power supplied from the high frequency power source to the electrode from the output terminal side toward the electrode side becomes rough. With this setting, the space in which the high-frequency current is propagated in the high-frequency power distribution body is expanded, the high-frequency resistance is substantially reduced, and the inductance is reduced. As a result, it is possible to reduce the limitation on the high-frequency current in the power distribution part from the output terminal to the electrode, for example, from the matching circuit output terminal that is about one bolt thick as the output terminal of the tuning capacitor. The high frequency resistance up to an electrode having a diameter of about 100 cm can be reduced. As a result, it is possible to reduce the loss of high-frequency power supplied to the plasma generation space.
As a result, when the same frequency is supplied, the effective power consumed in the plasma space can be increased as compared with the conventional plasma processing apparatus, and the deposition rate is improved when the films are stacked. Can be achieved.
[0015]
24 and 25 are a perspective view for explaining the propagation state of the high-frequency power and a schematic graph showing the power energy density.
Here, “average density of power” is different from “current density” in the narrow sense, so to speak, “including the high-frequency power distribution body and the space around the high-frequency power distribution body” This means an “average value of energy per small volume in a plate-like space corresponding to the small length δi”.
That is, “in the high-frequency power distribution body, the average density per unit volume of the high-frequency power supplied from the high-frequency power source to the electrode from the output terminal side toward the electrode side is set to be rough.” Does not simply mean that the surface area of the high-frequency power distribution body through which the high-frequency current propagates is simply increased from the high-frequency power supply side toward the electrode side, as shown in FIGS. For example, the i axis is set with respect to the current propagation direction from the output terminal PR of the matching circuit, which is the output terminal of the tuning capacitor, to the electrode 4, and i corresponding to the small length δi on the i axis. In a plate-like space ΔV perpendicular to the axis, the energy density in a small volume δV therein tends to decrease from the output terminal PR side of the matching circuit toward the electrode 4 side along the i-axis. Than it is.
Specifically, as described later, from the output terminal PR side toward the electrode 4 side, “the number of high-frequency power distribution bodies increases”, “the cross-sectional area in a plane orthogonal to the i-axis of the high-frequency power distribution bodies increases” This means that the surface area of the high-frequency power distribution body as the high-frequency current transmission path is increased.
[0016]
In the present invention, the high-frequency power distribution body includes a plurality of high-frequency power distribution bodies, so that the high-frequency power distribution body supplies high-frequency power from the high-frequency power source to the electrodes as compared to a single high-frequency power distribution body. The average density per unit volume can be set to be coarse.
Here, as shown in FIG. 25, for example, in the case where three high-frequency power distribution bodies 3a are provided, in a plate-like space ΔV perpendicular to the i-axis, characteristics in the vicinity of the high-frequency power distribution body 3a therein. In the plate-like space ΔV1 perpendicular to the i-axis in the case where the energy density of the propagating high-frequency power in a small volume δV and a single high-frequency power distribution body 3 ′ shown in FIG. The energy density of the propagating high-frequency power in the small volume δV1 in the vicinity of the body 3 ′ is compared.
Then, in the plate-like space ΔV (ΔV1) perpendicular to the i-axis, for example, the partial space in which high-frequency power propagates in the case of three shown in FIG. 25 propagates high-frequency power in the case of one shown in FIG. Compared to the surface of the high-frequency power distribution body 3 ′ and the partial space around the high-frequency power distribution body 3 ′, the size is about three times as large as the number of high-frequency power distribution bodies 3a shown in FIG. For this reason, it can be said that the space for high-frequency power propagation is large in the plate-like space ΔV (ΔV1) perpendicular to the i-axis, corresponding to the number of high-frequency power distribution bodies.
[0017]
As a result, the plurality of high-frequency power distributors reduce the energy density in the small volume δV in the partial space in which the high-frequency power propagates, and the inductance is substantially reduced. The restriction on the high-frequency current in the part can be reduced. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be reduced.
As a result, it is possible to increase the effective high frequency power consumed in the plasma generation space.
Furthermore, by connecting a plurality of high-frequency power distribution bodies to the electrodes, it is possible to supply high-frequency power from a plurality of points to the electrodes, which is a problem when supplying power to the electrodes from a single feeding position. The plasma excitation electrode has a distribution in the plasma density due to the standing wave when the size of the plasma excitation electrode (the longest distance from the feeding position to the periphery of the electrode) is larger than the quarter wavelength of the plasma excitation frequency (high frequency power frequency), It is possible to prevent the uniformity of the film thickness and film quality within the substrate surface from being impaired.
[0018]
In the present invention, it is sufficient that the high-frequency power distribution body has a plurality of portions, and the case where there is a single-path connection portion in the current path (distribution body portion) from the output terminal of the matching circuit to the electrode is also included. Shall. For example, when a plurality of high-frequency power distribution bodies are connected to the plasma excitation electrode from the output terminal PR of the matching circuit, which is the output terminal of the tuning capacitor, a plurality of the high-frequency power distribution bodies are connected via the single path portion connected to the output terminal PR. Connecting a high-frequency power distribution body of a book, for example, it is possible to connect the apex portion of a conical high-frequency power distribution body (cone) to an output terminal and connect a plurality of high-frequency power distribution bodies to the bottom. It is. In other words, it means “having at least a portion composed of a plurality of high-frequency power distribution bodies”.
[0019]
In the present invention, the plurality of high-frequency power distribution bodies are provided in parallel to each other, so that a high-frequency current propagating on the surfaces of the plurality of high-frequency power distribution bodies is created in a space between the plurality of high-frequency power distribution bodies. The magnetic fields cancel each other, and the cancellation can be set to be equal in the range where the distances between the plurality of high-frequency power distribution bodies in the propagation direction are equal, and the cancellation is equal to the extending direction of the high-frequency power distribution bodies Therefore, it is possible to reduce the inductance in the power distribution part, and thereby it is possible to further increase the effective high-frequency power consumed in the plasma generation space.
[0020]
Further, in the present invention, a means in which the plurality of high frequency power distribution bodies are connected to the electrode in an axially symmetric state with respect to the center of the electrode, specifically, two high frequency powers are used. Distributing the distances to the corresponding points of the power distribution bodies equal to each other, or connecting the distances between the three or more high-frequency power distribution bodies equal to each other to the electrodes, or perpendicular to the i-axis When three or more high-frequency power distribution bodies are located in a flat plate-like space ΔV, the magnetic fields created by the plurality of high-frequency power distribution bodies are arranged by equally arranging the distances between the three or more high-frequency power distribution bodies. Are set so as to cancel each other, and the inductance in the power distribution portion can be further reduced. At the same time, a plurality of high-frequency power distribution bodies are connected to the electrode in an axially symmetric state with respect to the center of the electrode, thereby preventing the occurrence of drift in the electrode and generating a distribution in plasma density. It is possible to prevent the uniformity of the thickness and film quality within the substrate surface from being impaired.
[0021]
Here, the electrode center corresponds to the center position in the electrode surface direction of the plasma generation space. For example, when the planar shape of the electrode is a circle, the center of the electrode is the center point, and when the electrode is a rectangle, the center of the electrode is the intersection of two diagonal lines. Is done.
Axisymmetric means that it is spatially symmetrical with respect to an axis that passes through the electrode center and is perpendicular to the electrode surface, that is, the connection position and connection angle (electrodes) of the respective high-frequency power distribution bodies with respect to the electrode center. This means that the conditions such as the angle between the axis passing through the center and perpendicular to the electrode surface and the axial direction of the high-frequency power distribution body are equal. That is, the positions at which a plurality of high-frequency power distribution bodies are attached to the electrodes are axisymmetric, and the attachment state of each high-frequency power distribution body to the electrodes, that is, the distance from the electrode center even at positions away from the electrode surface Axisymmetric with respect to each other. Furthermore, when the cross-sectional shape in the direction orthogonal to the i-axis is not a shape that does not depend on the mounting angle, such as a circle, the high-frequency power distribution body is set with respect to a straight line that passes through the mounting position and the electrode center on the electrode surface The attached mounting angles are all set equal.
[0022]
Further, since the plurality of high-frequency power distribution bodies are connected to each other by a connection body, the high-frequency power supplied in the distribution body portion from the output terminal to the electrode of the matching circuit is compared with the case where no connection body is provided. When the average density per unit volume is roughened, the interval between the high-frequency power distribution bodies connected to the electrodes can be set large, so that the energy density in the partial space where the high-frequency power propagates is further reduced. In particular, the inductance can be reduced, and the restriction on the high-frequency current in the feeding portion can be further reduced. At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced.
As a result, the effective high frequency power supplied to the plasma generation space can be further increased.
Further, since the interval between the high-frequency power distribution bodies connected to the electrodes can be set large, the size of the plasma excitation electrode 4 (from the feeding point) that has been a problem when power is supplied to the electrodes from a single point. The distribution of the plasma density is caused by the standing wave when the longest distance to the periphery of the electrode is larger than the 1/4 wavelength of the plasma excitation frequency (high frequency power frequency), and the film thickness and film quality are uniform within the substrate surface. This can be more effectively prevented when high-frequency power is supplied from a plurality of points to the electrode.
[0023]
In the present invention, the connection body is provided with a surface substantially parallel to the electrode, so that a plurality of high-frequency power distribution bodies are symmetrical with respect to the center axis of the electrode center. Since a surface that can be connected to the connection body and is orthogonal to the propagation direction of the high-frequency current is provided, a plurality of high-frequency power distribution bodies having the same length are provided, and the high-frequency power distribution body can easily have the same high-frequency impedance. It is possible to equalize the current flowing through each high-frequency power distribution body, which is more effective in preventing drift. Here, when the high-frequency power distribution bodies are arranged in non-parallel, the lengths are different when equalizing the high-frequency impedances in the high-frequency power distribution bodies, so it is necessary to consider the respective thicknesses. In addition, by using such a high-frequency power distribution body, it is possible to prevent drift, further reduce the energy density in the partial space where the high-frequency power propagates between the connection body and the electrode, and substantially reduce the inductance. Further, the restriction on the high-frequency current in the power feeding portion can be further reduced. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced. As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
[0024]
Further, by connecting the plurality of high-frequency power distribution bodies to the connection body in an axially symmetric state with respect to the center of the connection body, by connecting symmetrically with respect to the central axis of the connection body center, In the subspace where the high frequency power propagates, it is possible to prevent the drift between the connection body and the electrode, and to prevent the distribution of the plasma density from occurring and the film thickness and film quality from being impaired in the substrate surface. The energy density can be further reduced, the inductance can be substantially reduced, and the restriction on the high-frequency current in the feeding part can be further reduced. At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced. As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
[0025]
In addition, since the connection body is a plate-like body having a shape similar to that of the electrode, when the high-frequency power distribution body is connected to both side surfaces of the connection body that is a plate-like body, the matching circuit of the connection body By setting the connection state of the high-frequency power distribution body on the side of the output terminal and the side of the electrode so that the average density per unit volume of the supplied high-frequency power is coarse, the space where the high-frequency power propagates is similar to the electrode Can be as big as As a result, when the space in which high-frequency power propagates from the output terminal side to the electrode side of the matching circuit is increased, the drift is prevented and the plasma density is distributed, and the film thickness and film quality are uniform within the substrate surface. Can be prevented, and the energy density in the subspace where the high-frequency power propagates can be further reduced, the inductance can be substantially reduced, and the restriction on the high-frequency current in the power feeding portion can be further reduced. . At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced.
As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
Here, the connection state being in a similar state means that the contour shapes of the connection body and the electrode as seen from the direction along the current propagation path (i-axis direction) are similar to each other. Is provided in a state that is not orthogonal to the i-axis, it means that the contour shape projected onto the surface orthogonal to the i-axis is similar.
[0026]
In the present invention, the plurality of high-frequency power distribution bodies are connected so as to be in a similar state on the front surface and the back surface of the connection body, respectively, from the output terminal side of the matching circuit toward the electrode side, When setting the average density per unit volume of the supplied high-frequency power to be coarse, the space in which the high-frequency power propagates on both sides of the connection body in the propagation direction can be enlarged as a similar shape, When increasing the space in which high-frequency power propagates from the output terminal side to the electrode side of the matching circuit, uneven flow is prevented and the plasma density is distributed, and the uniformity of film thickness and film quality within the substrate surface is impaired. In addition, the energy density in the partial space where high-frequency power propagates is further reduced, and the inductance is substantially reduced. It is possible to further reduce the limit for current. At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced.
As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
Here, the high-frequency power distribution body being connected in a similar state means that the connection positions viewed from the direction along the current propagation path are similar to each other, and the connection positions of the high-frequency power distribution bodies are similar to each other. This means that the conditions such as the spacing ratio and angle (positional relationship), and the connection angle (angle between the connection surface of the connection body and the axial direction of the high-frequency power distribution body) are equal.
[0027]
In the present invention, a plurality of the connection bodies are provided from the output terminal side to the electrode, so that a space in which high-frequency power propagates from the output terminal side of the matching circuit to the electrode is increased and supplied. It is possible to set the average density per unit volume of the high-frequency power to be coarsened in multiple stages, whereby the electrode having a diameter of about 60 cm while the high-frequency power distribution body satisfies the parallel and axially symmetric conditions. Even when the plasma processing is performed on the substrate to be processed having a diameter of about 50 cm, that is, even when it is necessary to increase the diameter of the substrate to be processed and to increase the diameter of the electrode necessary for the plasma processing. In such a case, since the distance from the feeding point to the electrode edge increases, drift tends to occur and the high frequency resistance tends to increase. It is possible to prevent the distribution of the density from occurring and to prevent the uniformity of the processing result within the substrate surface, for example, the uniformity of the film thickness and film quality within the substrate surface, and the partial space in which the high-frequency power propagates. The energy density at can be further reduced, the inductance is substantially reduced, and the restriction on the high-frequency current in the power feeding portion can be further reduced. At the same time, the energy density in the small volume δV is reduced in the partial space where the high-frequency power propagates, and the high-frequency resistance is substantially reduced, so that the power loss in the power feeding portion can be further reduced. As a result, it is possible to further increase the effective high-frequency power consumed in the plasma generation space.
[0028]
In the present invention, in the plurality of high-frequency power distribution bodies, the high-frequency characteristics of the high-frequency power distribution body are set to be equal to each other, that is, the diameter dimension, the cross-sectional shape, the length dimension in the plurality of high-frequency power distribution bodies, Etc. are set as equal as possible to equalize the high-frequency resistance and inductance of multiple high-frequency power distribution bodies as current propagation paths, prevent the occurrence of drift, and cause a distribution in plasma density. The uniformity of the processing result within the substrate surface, for example, the uniformity of the film thickness and film quality within the substrate surface can be prevented from being impaired. Here, the diameter dimension and the cross-sectional shape of the electrode surface or the connection surface of the connection body, that is, the plurality of high-frequency power distribution bodies connected to the same connection surface are all set equal, and the length of the plurality of high-frequency power distribution bodies When the dimension is also set equal, the connection surface between the electrode surface and the connection body can be in a parallel state. In addition, it is preferable that the diameter dimension, the cross-sectional shape, and the length dimension of the plurality of high-frequency power distribution bodies connected to different connection surfaces are set to be equal at the connection surface of the electrode or the connection body. When a high-frequency power distribution body and / or a connection body are connected to each other, it is possible to easily set high-frequency characteristics at each stage.
[0029]
In the present invention, the surface of the high-frequency power distribution body and / or the connection body is provided with a low resistance portion made of a low resistance material compared to the center portion, so that it flows only near the conductor surface due to the skin effect. With respect to the high-frequency current, the high-frequency resistance in the portion where the high-frequency current propagates can be further reduced. As a result, the high-frequency resistance can be reduced without depending on the shape such as the thickness and length of the high-frequency power distribution body and / or the connection body, and the power loss in the power feeding portion can be reduced. In addition, it is possible to reduce the loss of high-frequency power supplied to the plasma generation space.
This low resistance portion is, for example, Au, Ag, Cu and these as low resistance materials for the base material (center portion) of the high frequency power distribution body and / or connection body made of Al, stainless steel, Cu or the like. Alloys containing can be applied. Further, the low resistance portion can be provided only on the entire surface of the high-frequency power distribution body, the entire front and back surfaces of the connection body, or a part thereof, for example, a preferable place when set as a high-frequency current propagation path. .
FIG. 28 and FIG. 29 are examples of a configuration in which a low resistance portion is provided.
As an example of such a configuration, as shown in FIG. 28, the high-frequency power distribution bodies 31 and 32a are provided with a low resistance portion on the entire surface, although not shown, and at the same time, in the connection body C31, the high-frequency power distribution body 31 A low resistance portion RL is provided on the entire surface of the high frequency power supply side (output terminal PR side described later) and the side surface to be connected, and each high frequency is provided on the electrode side surface to which the high frequency power distribution body 32a is connected. The low resistance portion RL may not be provided on the center C30 side from the position where the power distribution body 32a is connected, and the low resistance portion RL may be provided on the outer side, that is, on the edge side, from the position where each high frequency power distribution body 32a is connected. As a result, when the high frequency current flows along the skin effect, the low resistance portion is provided only on the surface portion having a large influence on the high frequency current.
As another example, as shown in FIG. 29, although not shown in the high-frequency power distribution bodies 32b and 34b, a low resistance portion is provided on the entire surface, and at the same time, in the connection body C32, the connection of the high-frequency power distribution body 32b is performed. The high-frequency power distribution side is not provided with a low resistance portion RL on the side of the center C30 from the position where each high-frequency power distribution body 32b is connected to the surface and side surfaces of the high-frequency power supply side (output terminal PR side described later). The low resistance portion RL is provided on the outer side, that is, on the edge side of the position where the high frequency power distribution body 34b is connected, and the center C30 is provided on the electrode side surface where the high frequency power distribution body 34b is connected. The low resistance portion RL is not provided on the side, and the low resistance portion RL can be provided on the outer side, that is, on the edge side, from the position where each high frequency power distribution body 34b is connected. As a result, when the high-frequency current flows along the skin effect, the low resistance portion is provided only on the outer portion of the surface having a large influence on the high-frequency current i.
As examples of the above, all are regular triangle T shown in FIG. 4 to be described later, regular triangles T1 to T3 shown in FIG. 19, square Q as shown in FIGS. 9 and 10, and regular pentagon as shown in FIG. It is possible not to provide a low resistance portion on the inner side of the polygon to which the high frequency power distribution body formed by the vertices of QU or a regular hexagon,.
[0030]
At the same time, when Au, Ag, and an alloy containing these are applied as the low resistance portion, the surface of the base material of the high frequency power distribution body and / or the connection body generates heat, corrosion, Suppresses the occurrence of changes over time such as resistance increase due to oxidation and other alterations, protects the base material of the high-frequency power distribution body and / or connection body, prevents the high-frequency resistance from changing over time, It is possible to stably perform plasma processing with high reproducibility.
[0031]
Further, in the present invention, by adopting a means in which the thickness dimension of the low resistance portion is set to be larger than the skin depth at the high frequency power frequency supplied from the high frequency power source, the high frequency current can be effectively increased by the skin effect. Since the resistance value of the flowing portion can be reduced, the high frequency power supplied to the plasma generation space is reduced without affecting the strength of the high frequency power distribution body and / or the base of the connection body. It is possible to further reduce the loss.
Here, the skin effect is, as shown in FIG. 5, when an alternating current flows through a conductor, the circumferential magnetic field generated by this current also changes with time, and this electromagnetic induction prevents changes in current. A counter electromotive force is generated in the direction, but at this time, since the number of magnetic flux linkages is larger as the current at the center of the conductor cross section, the back electromotive force also increases, so the current density at the center of the conductor cross section is reduced and the current is reduced. This means that the current flows through the periphery. At this time, the depth at which the current penetrates from the conductor surface into the conductor is defined as the skin depth. This skin depth is defined by the following formula (1).
[Expression 1]

here,
δ: skin depth
ω: High-frequency frequency supplied from a high-frequency power source
μ: Permeability (= μ₀ Vacuum permeability)
σ: Conductivity of low resistance member
It is.
[0032]
Further, in the present invention, the surface of the high-frequency power distribution body and / or the connection body is covered with an insulating film made of an insulator, whereby the high-frequency power distribution body and / or the connection body is subjected to oxidation or the like over time. It is possible to prevent the change, and to suppress the fluctuation of the high frequency resistance in the power distribution part, and to suppress the fluctuation factor of the plasma processing due to the time-dependent change of the high frequency characteristics generated in the high frequency power distribution body and / or the connection body. In addition, it is possible to perform a stable plasma process with high reproducibility, and in particular, it is possible to stabilize each plasma process result even when performing a plurality of plasma processes.
[0033]
Further, in the present invention, the high-frequency power distribution body and / or the connection body is made of a rigid body, so that variations in plasma processing that may occur due to changes in the plasma processing apparatus with the progress of plasma processing, particularly high-frequency It is possible to suppress the variation factors of the plasma processing aging due to the change in the high frequency characteristics of this part due to the deformation in the power distribution body and / or the connection body, and to perform a uniform and stable plasma processing in time, In particular, when performing plasma processing a plurality of times, each time the plasma processing is repeated, the respective plasma processing results can be stabilized.
Here, “rigid body” means that the high-frequency power distribution body and / or the connection body does not deform during plasma processing, that is, “the high-frequency characteristics do not change during operation”, and is accompanied by removal and assembly. It means “not deformed before and after maintenance” and “with reproducibility of the mounting position at the time of mounting”. As a result, the high-frequency characteristics set before the plasma treatment can be maintained after the plasma treatment and after the subsequent maintenance including disassembly and reassembly, so that it is possible to stably perform the plasma treatment with high reproducibility. .
[0034]
Furthermore, the high-frequency power distributor and / or the connection body is housed inside a shielding conductor connected to the chamber wall of the plasma processing chamber, without impairing the degree of freedom of the installation location of the matching circuit, It is possible to further reduce the energy density in the partial space where the high-frequency power propagates in the power distribution body part, substantially reduce the inductance, and further reduce the restriction on the high-frequency current in the power feeding part. At the same time, the energy density in the small volume δV is reduced in the partial space where the high-frequency power propagates, and the high-frequency resistance is substantially reduced, so that the power loss in the power feeding portion can be further reduced. As a result, it is possible to further increase the effective high-frequency power consumed in the plasma generation space.
Moreover, unnecessary radiation to the outside can be blocked.
Here, the shield conductor is composed of a matching box in which the matching circuit is housed and a chassis connected to the matching box, and the matching circuit and the chamber in which the plasma excitation electrode is provided are separated from each other. In the case where the shield conductor is installed, the shielding conductor includes a matching box, a chassis, and a housing portion that connects the chassis and the chamber and accommodates a power distribution portion. This makes it possible to shield the power feeding portion regardless of the positional relationship among the matching circuit, the electrode, and the chamber.
Here, for example, the matching box is connected to the outer conductor of a power supply line that is a coaxial cable from a high-frequency power source and is at a ground potential, and the chassis or housing is connected to the chamber wall and the matching box. These chamber wall, housing, chassis, matching box, and outer conductor each constitute a path for returning the high-frequency current supplied from the high-frequency power source to the power source side, that is, a return path of the current path.
[0035]
In the plasma processing apparatus of the present invention, in each of the plasma processing apparatuses described above, a plurality of the plasma processing chamber units are provided, so that the high frequency of the power distribution unit portion with respect to the plurality of plasma chambers (plasma processing chamber units). It is possible to reduce the difference in electrical high frequency characteristics such as resistance, and to reduce the difference in effective power consumed in the plasma space in each plasma chamber.
As a result, the same process recipe is applied to a plurality of plasma chambers to reduce variations in plasma processing results, that is, when film formation is performed in a plurality of plasma chambers, for example, film thickness, dielectric strength It is possible to prevent a difference in film characteristics such as etching rate.
[0036]
In the plasma processing system of the present invention, it is possible to provide a plasma processing system capable of producing the same effects as the above-described plasma processing apparatus by employing means in which a plurality of the above-described plasma processing apparatuses are provided. It becomes possible.
[0037]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plasma processing apparatus and a plasma processing system according to a first embodiment of the present invention will be described with reference to the drawings.
[First Embodiment]
FIG. 1 is a diagram showing a schematic configuration of a plasma processing apparatus 71 of the present embodiment. The plasma processing apparatus 71 of the present embodiment can perform integrated processing from the formation of polycrystalline silicon, which forms a semiconductor active film of a top gate TFT, to the formation of a gate insulating film, for example. The apparatus has a chamber unit.
[0038]
In the plasma processing apparatus 71 of the present embodiment, as shown in FIG. 1, five processing chamber units, one loader chamber 73 and one unloader chamber 74 are connected around a substantially heptagon shaped transfer chamber 72. It is installed. The five processing chamber units include a first film formation chamber for forming an amorphous silicon film, a second film formation chamber for forming a silicon oxide film, and a third film formation for forming a silicon nitride film. Plasma processing chamber units (plasma chambers) 75, 76, 77 composed of chambers, a laser annealing chamber 78 for performing an annealing treatment of a substrate to be processed after film formation, and a heat treatment chamber 79 for performing a heat treatment of the substrate to be processed after film formation. is there.
[0039]
The first film forming chamber 75, the second film forming chamber 76, and the third film forming chamber 77, which are plasma processing chamber units (plasma chambers), can also perform different processes such as forming different types of films. In addition, although the same process can be performed by the same process recipe, the configuration is substantially the same. In the plurality of plasma chambers 75, 76, 77, as will be described later, in the power distribution section 3, the high-frequency power distribution bodies 31, 32 a are composed of a plurality of pieces, and the high-frequency power distribution bodies 31, 32 a are connected. Setting is made so that the average density per unit volume of the high frequency power supplied from the high frequency power supply 1 to the electrode 4 from the output terminal PR side to the electrode 4 side is coarsened by being connected to each other by a plate (connector) C31. It is set as the structure.
Here, the configuration of the first film formation chamber 75 will be described as an example.
[0040]
2 is a cross-sectional view showing a schematic configuration of the plasma processing chamber unit (plasma chamber) of the present embodiment, FIG. 3 is a perspective view showing a power distribution portion 3 of the plasma processing chamber unit (plasma chamber) in FIG. 2, and FIG. It is a top view which shows the electrical power distribution part 3 and the plasma excitation electrode 4 of FIG.
[0041]
The plasma chamber (first film forming chamber) 75 is a one-frequency excitation type plasma processing chamber unit capable of plasma processing such as CVD (chemical vapor deposition), sputtering, dry etching, ashing, etc., as shown in FIG. Parallel plate electrodes 4 and 8 for exciting plasma are provided, and impedance matching between the high-frequency power source 1 connected to the electrodes 4 via the power distribution part 3 and the plasma chamber 75 and the high-frequency power source 1 is provided. And a matching circuit 2A for obtaining the above.
[0042]
More specifically, as shown in FIGS. 2 and 3, the plasma chamber 75 includes a plasma excitation electrode (electrode) 4 connected to the high-frequency power source 1 and a shower at an upper position of the chamber chamber (plasma processing chamber) 60. A plate 5 is provided, and a susceptor electrode (counter electrode) 8 on which the substrate 16 to be processed is placed is provided below the chamber chamber 60 so as to face the shower plate 5. The plasma excitation electrode 4 is connected to the first high-frequency power source 1 via the power distribution part 3 and the matching circuit 2A. The plasma excitation electrode 4 and the power distribution part 3 are covered with a chassis 21 and the matching circuit 2A is housed in a matching box 2 made of a conductor. The chassis (shielding conductor) 21 and the matching box (shielding conductor) 2 are connected to each other. As will be described later, the matching box 2 is connected to the shield line (outer conductor) of the feeder 1A that is a coaxial cable. Yes.
[0043]
The plasma excitation electrode (cathode electrode) 4 has a circular outline with a diameter of about 30 cm corresponding to the plasma chamber 60 whose cross section in the direction of the plasma excitation electrode 4 is circular. Further, an annular convex portion 4 a is provided below the plasma excitation electrode (electrode) 4, and a shower plate 5 in which a large number of holes 7 are formed below the plasma excitation electrode (cathode electrode) 4. Is provided in contact with the convex portion 4a. A space 6 is formed between the plasma excitation electrode 4 and the shower plate 5. A gas introduction pipe 17 is connected to the space 6 through the side wall of the chassis 21 and through the plasma excitation electrode (cathode electrode) 4.
[0044]
The gas introduction pipe 17 is made of a conductor, and an insulator 17a is inserted in the middle of the gas introduction pipe 17 at a position inside the chassis 21 so that the plasma excitation electrode 4 side and the gas supply source side are insulated.
The gas introduced from the gas introduction pipe 17 is supplied into the chamber chamber 60 formed by the chamber wall 10 through the numerous holes 7 and 7 of the shower plate 5. The chamber wall 10 and the plasma excitation electrode (cathode electrode) 4 are insulated from each other by an insulator 9. In FIG. 2, the exhaust system to be connected to the chamber chamber 60 is not shown.
On the other hand, a disk-shaped wafer susceptor (susceptor electrode) 8 on which the substrate 16 is placed and also serves as a plasma excitation electrode is provided in the chamber chamber 60.
[0045]
A shaft 13 is connected to the center of the lower portion of the susceptor electrode (counter electrode) 8. The shaft 13 is provided through the chamber bottom 10 </ b> A, and the lower end of the shaft 13 and the center of the chamber bottom 10 </ b> A are connected by the bellows 11. Sealed connection. The wafer susceptor 8 and the shaft 13 can be moved up and down by the bellows 11, and the distance between the plasma excitation electrodes 4 and 8 can be adjusted.
Since the susceptor electrode 8 and the shaft 13 are connected, the susceptor electrode 8, the shaft 13, the bellows 11, the chamber bottom 10A, and the chamber wall 10 have the same potential in terms of DC. Furthermore, since the chamber wall 10 and the chassis 21 are connected, the chamber wall 10, the chassis 21, and the matching box 2 are all at the same potential in terms of DC.
[0046]
Here, the matching circuit 2 </ b> A is configured to include a plurality of passive elements in order to adjust the impedance in response to a change in the plasma state or the like in the chamber chamber 60. Specifically, as shown in FIG. 2, the matching circuit 2A is provided as a plurality of passive elements between the high frequency power source 1 and the power feeding plate 3, and includes an inductance coil 23, a tuning capacitor 24 made of an air variable condenser, And a load capacitor 22 made of a vacuum variable capacitor.
Among these, the inductance coil 23 and the tuning capacitor 24 are connected in series from the input terminal side to the output terminal PR side of the matching circuit 2A, and the load capacitor 22 is connected in parallel with the branch point between the inductance coils 23. It is connected. The inductance coil 23 and the tuning capacitor 24 are directly connected without a conductor, and one end of the load capacitor 22 is connected to the matching box (ground potential portion) 2 via the conductor.
Here, the tuning capacitor 24 is the final end of the passive elements of the matching circuit 2A, the output terminal of the tuning capacitor 24 is the output terminal PR of the matching circuit 2A, and the tuning capacitor 24 is the distribution part (high frequency power). It is connected to the plasma excitation electrode 4 via a power distribution body 3.
[0047]
The matching box 2 is connected to a shield line of a feeder line (high-frequency power feeder) 1A that is a coaxial cable, and this shield line is grounded in a DC manner. As a result, the susceptor electrode 8, the shaft 13, the bellows 11, the chamber bottom 10A, the chamber wall 10, the chassis 21, and the matching box 2 are set to the ground potential, and at the same time, one end of the load capacitor 22 is also grounded in a DC manner. It will be in the state.
[0048]
As shown in FIG. 3, as the power distribution portion 3 connected to the output terminal PR and the plasma excitation electrode 4, all of them have a circular cross-sectional shape with a diameter of 2 to 10 mm and a length of 100 to 300 mm. A rod-shaped copper-made rigid high-frequency power distribution body 31, 32a is connected to each other by a connection plate (connection body) C31. One end of the high-frequency power distribution body 31 is connected to the matching circuit 2A. The output terminal PR is detachably attached to the output terminal of the tuning capacitor 24 by a coupling means such as a screw, and the other end of the high-frequency power distribution body 31 is the front side (matching circuit) of the connection plate (connection body) C31. 2A output terminal PR side surface) and is connected orthogonally.
[0049]
The connection plate C31 has a contour shape smaller than that of the plasma excitation electrode 4 and is a circular plate having a diameter of about 20 cm, which is similar to the plasma excitation electrode 4, and is, for example, a rigid copper plate having a thickness of about 2 mm. Has been. The connection plate C31 is provided between the plasma excitation electrode 4 and the output terminal PR of the matching circuit 2A so that the back side surface thereof faces the plasma excitation electrode 4 in a parallel state.
Here, the connection plate C31 being in a similar state to the plasma excitation electrode 4 means that the contour shape of the connection plate C31 viewed from the direction along the current propagation path (i-axis direction) is similar to each other. Yes.
[0050]
A plurality of high-frequency power distribution bodies 32a are vertically suspended from the back side surface (side surface of the plasma excitation electrode 4) of the connection plate (connection body) C31, and the other end of these high-frequency power distribution bodies 32a is connected to the plasma. The excitation electrode 4 is connected orthogonally to the surface. That is, the high-frequency power distributor 32 a is provided in parallel with the i-axis, which is the current propagation direction from the output terminal PR to the plasma excitation electrode 4, which is orthogonal to the plasma excitation electrode 4.
[0051]
In the high frequency power distribution bodies 31 and 32a of the present embodiment, the average density per unit volume of the high frequency power supplied from the high frequency power source 1 to the plasma excitation electrode 4 from the output terminal PR side toward the electrode 4 side is rough. It is set to become. In other words, from one end of one high-frequency power distribution body 31 attached to the output terminal PR of the tuning capacitor 24 to the other end of the plurality of high-frequency power distribution bodies 32a connected to the surface of the plasma excitation electrode 4, The space in which the high-frequency current is propagated in the high-frequency power distribution bodies 31 and 32a is widened so that the high-frequency resistance is substantially reduced and the inductance is reduced.
Specifically, the output terminal PR side is a single high-frequency power distribution body 31, and the plasma excitation electrode 4 side is the three high-frequency power distribution bodies 32a. About 3 times.
[0052]
Here, for example, a plurality of high-frequency power distribution bodies 32a, which are three, are connected to the plasma excitation electrode 4 in parallel with each other and in an axially symmetric state with respect to the center 40 of the circular plasma excitation electrode 4. Has been. Here, the axial symmetry means that it is spatially symmetrical with respect to an axis L that passes through the electrode center 40 and is perpendicular to the surface of the plasma excitation electrode 4, that is, each high-frequency power distributor 32a is as shown in FIG. In addition, the connection position is set so that the center of the regular triangle T coincides with the electrode center 40 at the vertex of the regular triangle T.
Similarly, the plurality of high-frequency power distribution bodies 32a are located at the apex of the regular triangle T on the back side surface (side surface of the plasma excitation electrode 4) of the connection plate (connection body) C31. The connection position is set so that the center C30 of the connection plate C31 coincides.
The high-frequency power distribution body 31 is connected to the center C30 position on the front side surface (side surface of the output terminal PR of the matching circuit 2A) of the connection plate C31, and passes through the electrode center 40 to the plasma excitation electrode 4 surface. They are provided in equilibrium with the vertical axis L, that is, coincident with this axis L.
Here, the lengths of the plasma excitation electrode 4 and the connection plate C31, that is, the lengths of the plurality of high-frequency power distribution bodies 32a connected to the same connection surface are set equal to each other. The connection surfaces facing C31 can be in a parallel state.
[0053]
Here, the high-frequency power distribution bodies 31 and 32a and the connection plate C31 are made of rigid bodies so that the high-frequency power distribution bodies 31 and 32a and the connection plate C31 are not deformed so that the high-frequency characteristics are changed during operation. It is supposed to be made of Cu having the dimensions as follows. At the same time, this rigid body means “not deformed before and after maintenance” accompanied by removal and assembly and “having reproducibility of the mounting position at the time of mounting”. Specifically, the high-frequency power distribution bodies 31 and 32a that are not deformed and the connection plate C31 are connected to each other by a coupling means such as a screw, and these are connected to the output terminal PR and the plasma excitation electrode 4. However, in this case, the accuracy of the connection state is assumed to have reproducibility, or the connection state is assumed to be not deformed by, for example, welding.
[0054]
On the surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31, a low resistance portion RL made of a low resistance material such as Au or Ag is provided compared to the central portion made of Cu. Here, the thickness dimension of the low resistance portion RL is set larger than the skin depth at the high frequency power frequency supplied from the high frequency power source 1.
FIG. 5 is a cross-sectional view for explaining the low resistance portion RL and the skin depth δ of the high frequency power distribution bodies 31 and 32a and the connection plate C31.
Here, as shown in FIG. 5, when the alternating current i is flowing through the high-frequency power distribution bodies 31 and 32a made of copper, for example, the skin depth is also the circumferential magnetic field generated by the current i. The counter electromotive force is generated in the direction that changes with time and prevents the change of current due to this electromagnetic induction.At this time, the number of magnetic flux linkages is larger as the current is at the center of the conductor cross section, so the counter electromotive force is also larger. The depth at which the current i penetrates from the surface of the high-frequency power distribution bodies 31 and 32a into the high-frequency power distribution bodies 31 and 32a when the density decreases and as a result, the current flows near the surface. (2).
[Expression 2]

here,
δ: skin depth
f: High frequency supplied from the high frequency power source
μ: Permeability (= μ₀ Vacuum permeability)
σ: conductivity
It is.
[0055]
For example, when power of a frequency f of about 13.56 MHz is supplied from a high-frequency power source, the skin depth in the low resistance portion RL of the high-frequency power distribution bodies 31 and 32a to be Ag is:
Conductivity σ = 1.10 × 10⁸S / m, permeability μ = μ₀Then,
The skin depth δ = 1.30 × 10 μm,
The thickness of the low resistance portion RL is provided on the surfaces of the high frequency power distribution bodies 31 and 32a and the connection plate C31 by, for example, plating so that δ = 1.30 × 10 μm.
Further, the low resistance portion RL can be similarly provided (silver-plated) on the side surface of the connection plate C31 of the electrode 4 made of Al, Cu, stainless steel or the like to which the high frequency power distribution body 32a is connected. It becomes possible to reduce the high-frequency resistance of the power feeding portion.
[0056]
The surfaces of the high-frequency power distributors 31, 32a and the connection plate C31 are covered with an insulating coating PC made of an insulator. Here, the surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31 mean the entire surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31, and when the low resistance portion RL is provided, The surface of the low resistance part RL is covered.
Here, as the insulating coating PC, polyimide, PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), PTFE (polytetrafluoroethylene), ETFE (tetrafluoroethylene-ethylene copolymer), etc. are applied. . Here, when polyimide, PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), or PTFE (polytetrafluoroethylene) is used as the insulating coating PC, it is possible to take advantage of the excellent heat resistance, and ETFE When (tetrafluoroethylene-ethylene copolymer) is employed, it is possible to take advantage of the property of being excellent in wear resistance.
[0057]
In the plasma chamber 75 of the present embodiment, the power of the frequency of about 13.56 MHz or more, specifically, the power of the frequency of 13.56 MHz, 27.12 MHz, 40.68 MHz or the like, for example, is applied, and both electrodes 4 , 8 is generated, and plasma processing such as CVD (chemical vapor deposition), dry etching, and ashing can be performed on the substrate 16 placed on the susceptor electrode 8 by this plasma.
[0058]
At this time, the high-frequency power is supplied from the high-frequency power source 1 as a power feeding portion to the coaxial cable of the feeder line 1A, the matching circuit 2A, the high-frequency power distributor 31, the connection plate C31, the high-frequency power distributor 32a, the plasma excitation electrode (cathode electrode) 4 is supplied. On the other hand, when considering the path of the high-frequency current, the current passes through the plasma space (chamber chamber 60) through these power feeding portions, and then the other electrode (susceptor electrode) 8, shaft 13, susceptor shield 12, bellows. 11, passes through the chamber bottom 10 </ b> A and the chamber wall 10, then passes through the chassis 21, the matching box 2, and the shield wire of the feeder 1 </ b> A to return to the ground of the high-frequency power source 1.
The shaft 13, the susceptor shield 12, the bellows 11, the chamber bottom 10A, the chamber wall 10, the chassis 21, the matching box 2, and the shield line of the feeder line 1A are each supplied with a high-frequency current supplied from the high-frequency power source 1. The path returning to the ground side of the current path, that is, the return path of the current path is configured.
[0059]
When forming an amorphous silicon film, a silicon oxide film, a silicon nitride film or the like in any of the processing chambers 75, 76, 77 having the above-described configuration, the substrate 16 to be processed is placed on the susceptor electrode 8, and a high frequency A high-frequency power is applied from the power source 1 to the high-frequency electrode 4 and a reaction gas is supplied from the gas introduction tube 17 through the shower plate 6 into the chamber chamber 60 to generate plasma, and an amorphous silicon film, A silicon oxide film, a silicon nitride film, or the like is formed.
[0060]
As shown in FIG. 6, the laser annealing chamber 78 is provided with a laser light source 81 at the upper part of the chamber 80, while the stage 82 for placing the substrate to be processed 16 is orthogonal to the lower part of the chamber 80 in the X direction. , Y direction can be horizontally moved. A spot-like laser beam 83 (indicated by a one-dot chain line) is emitted from the emitting portion 81a of the laser light source 81, and at the same time, the stage 82 supporting the substrate 16 to be moved horizontally in the X and Y directions. Thus, the laser beam 83 can scan the entire surface of the substrate 16 to be processed. For the laser light source 81, for example, a gas laser using a halogen gas such as XeCl, ArF, ArCl, or XeF can be used.
The laser annealing chamber 78 may have various configurations as long as the laser annealing chamber 78 includes a laser light source that emits laser light and the spot-like laser light emitted from the laser light source can scan the entire surface of the substrate to be processed. The apparatus of the structure of this can be used. In this case, a gas laser using a halogen gas such as XeCl, ArF, ArCl, or XeF can be used as the laser light source. Depending on the type of film, another laser light source such as a YAG laser can be used, and pulsed laser annealing or continuous wave laser annealing can be used as a form of laser light irradiation. In addition, for example, a multi-stage electric furnace type apparatus can be used for the configuration of the heat treatment chamber.
[0061]
As shown in FIG. 7, the heat treatment chamber 79 is of a multistage electric furnace type, and is configured such that the substrate to be processed 16 is placed on each of the heaters 85 provided in multiple stages in the chamber 84. . The plurality of substrates to be processed 16 are heated by energization of the heater 85. A gate valve 86 is provided between the heat treatment chamber 79 and the transfer chamber 72.
[0062]
A loader cassette and an unloader cassette are detachably provided in the loader chamber 73 and the unloader chamber 74 shown in FIG. These two cassettes can accommodate a plurality of substrates 16 to be processed, the substrate 16 to be processed before film formation is stored in the loader cassette, and the substrate 16 to be processed after film formation is stored in the unloader cassette. Is done. A substrate transfer robot (transfer means) 87 is installed in a transfer chamber 72 located in the center of the processing chamber unit, the loader chamber 73 and the unloader chamber 74. The substrate transfer robot 87 has an arm 88 having an expandable / contractible link mechanism at an upper portion thereof. The arm 88 is rotatable and can be moved up and down, and supports and transfers the substrate 16 to be processed at the tip of the arm 88. It has become.
[0063]
In the plasma processing apparatus 71 configured as described above, the operation of each unit is controlled by the control unit except that the operator sets various processing conditions and processing sequences such as film forming conditions, annealing conditions, and heat treatment conditions in each processing chamber unit. It is configured to operate automatically. Therefore, when using the plasma processing apparatus 71, the substrate 16 to be processed before being set is set in the loader cassette, and if the operator operates the start switch, the substrate transfer robot 87 causes the substrate cassette to move into the processing chambers from the loader cassette. After the processing substrate 16 is transported and a series of processing is automatically performed sequentially in each processing chamber, it is accommodated in the unloader cassette by the substrate transport robot 87.
[0064]
Here, the high frequency characteristic of the power distribution body part 3 in the plasma chamber 75 of the plasma processing apparatus 71 of the present embodiment will be described.
[0065]
In the power distribution part (high frequency power distribution body) 3 of the plasma chamber 75 of the present embodiment, the average density per unit volume of the high frequency power supplied from the high frequency power source 1 from the output terminal PR side toward the plasma excitation electrode 4 side. The maximum value of is set to be coarse.
Here, the “average density of electric power” means “a plate-like shape corresponding to a length δi that is small in the propagation direction of energy propagating in the space including the high-frequency power distribution bodies 31 and 32a and the surrounding space”. Mean value of energy per unit volume in space ”means that the average density of power becomes rough, as shown in FIG. 3, the output of the matching circuit that is the output terminal of the tuning capacitor 24 In the plate-like space ΔV perpendicular to the i-axis corresponding to the small length δi on the i-axis, the i-axis is set with respect to the current propagation direction from the terminal PR to the plasma excitation electrode 4. This means that the energy density in the small volume δV in the vicinity of the high-frequency power distribution bodies 31 and 32a decreases from the output terminal PR side of the matching circuit toward the plasma excitation electrode 4 side along the i-axis. Specifically, from the output terminal PR side toward the plasma excitation electrode 4 side, the number of current flowing portions increases from one single high frequency power distribution body 31 to three high frequency power distribution bodies 32a. Even if it says simply, this has implement | achieved by this state, The cross-sectional area of the high frequency electric power distribution body 31 and 32a in the surface orthogonal to an i-axis has expanded, and the high frequency electric power distribution body 31 and 32a as a high frequency electric current transmission path | route has spread. It can also be seen from the fact that the surface area of the is widened.
[0066]
As a result, a space in which the high-frequency current is propagated in the high-frequency power distribution body 3 is expanded, the inductance is substantially reduced, and the high-frequency resistance is reduced. That is, when the high-frequency power distribution body 3 is composed of a plurality of pieces, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power is propagated. The restriction on the high-frequency current in the portion 3 can be reduced. At the same time, in the power distribution section 3, the space in which high-frequency power propagates from the matching circuit 2 </ b> A output terminal PR, which is an output terminal of the tuning capacitor 24, for example, about one bolt thick, to the plasma excitation electrode 4 is expanded. In the partial space where the power propagates, the energy density in the small volume δV is reduced, the high frequency resistance is substantially reduced, and the power loss in the power feeding portion can be reduced.
As a result, it is possible to increase the effective high frequency power consumed in the plasma generation space. In other words, when the same frequency is supplied, the effective power consumed in the plasma space can be increased as compared with the conventional plasma processing apparatus, and the deposition rate is improved when the films are stacked. As a result, the plasma processing result can be improved.
[0067]
In the power distribution portion (high frequency power distribution body) 3 of the plasma chamber 75 of the present embodiment, the high frequency power distribution body 31 is composed of a plurality of high frequency power distribution bodies 32a on the plasma excitation electrode 4 side. Compared to the portion, in the power distribution portion 3, particularly in the high frequency power distribution body 32a, the average density per unit volume of the high frequency power supplied from the high frequency power source to the plasma excitation electrode 4 can be set to be rough.
Here, as shown in FIG. 3, when the number of the high-frequency power distribution bodies 32a is set to 3, the energy density of the propagating high-frequency power per unit volume δV2 in the plate-like space ΔV2 perpendicular to the i-axis. ”And“ energy density of high-frequency power propagating ”per unit volume δV1 in the plate-like space ΔV1 perpendicular to the i-axis when the single high-frequency power distribution body 31 is formed. Then, the partial space in which the high-frequency power propagates in the plate-like space ΔV2 perpendicular to the i-axis corresponds to the surface of the high-frequency power distributor 31 and the partial space around the high-frequency power distributor 31 in ΔV1. The size is three times as large as the number of the high-frequency power distribution bodies 32a. For this reason, it can be said that the space for propagation of the high-frequency current supplied from the high-frequency power source 1 is increased in the plate-like space ΔV2 perpendicular to the i-axis, corresponding to the number of the high-frequency power distribution bodies 32a.
[0068]
As a result, the plurality of high-frequency power distribution bodies 32a includes a plurality of high-frequency power distribution bodies 32a, thereby reducing the energy density in the partial space where the high-frequency power propagates, substantially reducing the inductance, and reducing the high-frequency resistance. The energy density in the partial space where the high frequency power propagates from the high frequency power source 1 to the plasma excitation electrode 4 is further reduced, the inductance is substantially reduced, and the restriction on the high frequency current in the power supply portion is further reduced. At the same time, the energy density in the small volume δV is reduced in the partial space where the high-frequency power propagates, and the high-frequency resistance is substantially reduced, thereby further reducing the power loss in the feeding portion. it can. As a result, the effective high frequency power supplied to the plasma generation space can be further increased. The restriction on the high-frequency current can be reduced, and further, the loss of the high-frequency power supplied to the plasma generation space can be reduced.
Thereby, when the same frequency is supplied, the effective power consumed in the plasma space can be increased as compared with the conventional plasma processing apparatus, and the processing speed is improved. For example, the film is formed by plasma CVD or the like. In the case of stacking, the deposition rate can be improved. Further, the processing speed can be improved by increasing the plasma excitation frequency without changing the effective power consumed in the plasma space.
[0069]
Furthermore, by connecting a plurality of high-frequency power distribution bodies 32a to the plasma excitation electrode 4, it is possible to supply high-frequency power to the plasma excitation electrode 4 from a plurality of points that are the vertices of the equilateral triangle T shown in FIG. Therefore, the size of the plasma excitation electrode 4 (the longest distance from the feeding position to the periphery of the electrode), which has been a problem when supplying high-frequency power from a single point, is ¼ wavelength of the plasma excitation frequency (high-frequency power frequency). If it is larger than that, the standing wave will cause a distribution in the plasma density generated in the plasma generation space, resulting in non-uniformity in the in-plane direction of the substrate to be processed, and the film thickness and film quality within the substrate surface. It is possible to prevent the uniformity in the case from being impaired.
[0070]
In addition to the regular triangle T shown in FIG. 4 with respect to the plasma excitation electrode 4, a plurality of high frequency power distribution bodies 32 a are connected to the plasma excitation electrode 4, as shown in FIG. Two symmetrical points, or a polygon that is symmetrical with respect to the electrode center, for example, a square Q as shown in FIGS. 9 and 10, a regular pentagon QU as shown in FIG. 12, or , Regular hexagons,..., High frequency power can be supplied from a plurality of points.
[0071]
A plurality of high-frequency power distribution bodies 32a are provided in parallel to each other, so that a high-frequency current propagating on the surface of the plurality of high-frequency power distribution bodies 32a creates in a space between the plurality of high-frequency power distribution bodies 32a, In other words, when viewed in a plane orthogonal to the i-axis, the magnetic fields generated in the space inside the equilateral triangle T cancel each other, and this cancellation is a distance between the plurality of high-frequency power distribution bodies 32a in the propagation direction (i-axis direction). Can be set to be equal in the same range, that is, in the range between the connection plate C31 and the plasma excitation electrode 4 in the i-axis direction, the inductance in the power distribution portion 3 can be reduced, thereby further increasing the plasma. It is possible to reduce the loss of high-frequency power supplied to the generation space.
As a result, when the same frequency is supplied, the effective power consumed in the plasma space can be increased as compared with the conventional plasma processing apparatus, and the processing speed is improved. For example, when films are stacked by plasma CVD or the like, the deposition rate can be improved. Further, the processing speed can be improved by increasing the plasma excitation frequency without changing the effective power consumed in the plasma space.
[0072]
In addition, the plurality of high-frequency power distribution bodies 32a are axially symmetric with respect to the center of the plasma excitation electrode 4, that is, the distances between the three high-frequency power distribution bodies 32a are arranged equally and connected to the plasma excitation electrode 4. Therefore, the magnetic fields generated in the plate-like space ΔV2 perpendicular to the i-axis by the plurality of high-frequency power distribution bodies 32a can be canceled with each other, and the inductance in the distribution section 3 can be further reduced. . At the same time, the plurality of high-frequency power distribution bodies 32a are connected to the plasma excitation electrode 4 in an axially symmetric state with respect to the center of the plasma excitation electrode 4, thereby preventing the occurrence of drift in the plasma excitation electrode 4. It is possible to prevent the plasma density in the plasma generation space from being distributed and the uniformity of the film thickness and film quality within the substrate surface from being impaired.
[0073]
Since the plurality of high frequency power distribution bodies 32a are connected to each other by the connection plate C31 and this connection plate C31 is connected to the high frequency power distribution body 31, the 2A output of the matching circuit is obtained compared to the case where the connection plate C31 is not provided. When the average density per unit volume of the high-frequency power supplied from the terminal PR to the plasma excitation electrode 4 is roughened, the interval between the high-frequency power distribution bodies 32a connected to the plasma excitation electrode 4 is set. Since it can be set large, the energy density in the partial space where the high-frequency power propagates is further reduced, the inductance is further reduced, and the high-frequency resistance is reduced. As a result, the high-frequency power source 1 to the plasma excitation electrode 4 In the partial space where the high-frequency power propagates in the power supply part leading to, the energy density in a small volume δV is Will be small, to reduce substantially inductance, it is possible to reduce the restrictions on the high-frequency current at the feeding portion. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be reduced.
As a result, it is possible to increase the effective high frequency power consumed in the plasma generation space.
As a result, since the interval between the high-frequency power distribution bodies 32a connected to the plasma excitation electrode 4 can be set large, high-frequency power is supplied to the plasma excitation electrode 4 from a plurality of points, and plasma excitation is performed from the power supply position. Even if the plasma excitation electrode 4 is large enough to have a location where the size of the electrode 4 is larger than a quarter wavelength of the plasma excitation frequency (high frequency power frequency), the distribution of the plasma density is caused by the standing wave. It becomes possible to more effectively prevent the uniformity of the film thickness and film quality within the substrate surface from being impaired.
[0074]
Since the connection plate C31 is provided with a plane substantially parallel to the plasma excitation electrode 4, a plurality of high-frequency power distribution bodies 32a are symmetrical with respect to the central axis L of the electrode center 40 with respect to this plane. Since a surface that can be connected to the connection plate C31 and is orthogonal to the propagation direction (i-axis direction) of the high-frequency current is provided, a plurality of high-frequency power distribution bodies 32a having the same length are provided, and the high-frequency power distribution body 32a is provided. The high-frequency impedances of the high-frequency power distribution bodies 32a can be equalized easily, and the currents flowing through the high-frequency power distribution bodies 32a can be equalized. Further, by using such a high-frequency power distribution body, it is possible to prevent drift, and to further reduce the energy density in the partial space where the high-frequency power propagates between the connection body C31 and the plasma excitation electrode 4, thereby substantially reducing the inductance. Can be reduced, and the restriction on the high-frequency current in the power feeding portion can be further reduced. At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced. As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
[0075]
Further, a plurality of high-frequency power distribution bodies 32a are connected to the connection plate C31 in an axially symmetric state with respect to the center C30 of the connection plate C31, so that the center axis L passing through the center C30 of the connection plate C31. By connecting symmetrically, the drift in the high-frequency current flowing from the connection plate C31 to the high-frequency power distribution body 32a is prevented, the plasma density is distributed, and the uniformity of film thickness and film quality within the surface of the substrate to be processed is impaired. This can be prevented and the loss of the high frequency power supplied to the plasma generation space can be further reduced by reducing the inductance.
[0076]
By connecting the connection plate C31 to a plate-like body similar to the plasma excitation electrode 4, when the high-frequency power distribution body 32a is connected to both side surfaces of the connection plate C31 that is a plate-like body, By setting the connection state of the high-frequency power distribution body on the side surface of the output terminal PR and the side surface of the plasma excitation electrode 4 so that the average density per unit volume of the supplied high-frequency power becomes coarse, a space in which the high-frequency power propagates is set. It can be enlarged as a similar shape to the electrode. As a result, when the space in which high-frequency power propagates from the output terminal PR side to the plasma excitation electrode 4 side of the matching circuit 2A is increased, the drift is prevented and the plasma density is distributed, and the film thickness and film quality are to be processed. It is possible to prevent the uniformity in the substrate plane from being impaired, and the energy density in the small volume δV is reduced in the partial space where the high-frequency power of the power feeding portion propagates, so that the inductance is substantially reduced. This can reduce the restriction on the high-frequency current in the power feeding portion. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced.
As a result, the effective high-frequency power consumed in the plasma generation space can be further increased.
[0077]
A shape such as a diameter dimension, a cross-sectional shape, and a length dimension in the plurality of high-frequency power distribution bodies 32a are set to be equal, and the high-frequency characteristics in these high-frequency power distribution bodies 32a are set to be equal to each other. The high frequency resistances and inductances of the plurality of high frequency power distribution bodies 32a are made equal to prevent the occurrence of drift, and the distribution of plasma density is prevented and the uniformity of film thickness and film quality within the substrate surface is prevented. can do.
[0078]
In addition, in this embodiment, although the cross-sectional shape of the high frequency electric power distribution body 32a was circular, in addition to this, the square shown in FIG. 9, the cross-sectional rectangle shown in FIG. 15, the regular triangle shown in FIG. A polygonal section such as a regular pentagon, or a plate-like body having an L-shaped section shown in FIGS. 10 and 13 so as to be the above-mentioned rigid body, or a plate-like body having a T-shaped section shown in FIG. It is also possible to set as In this case, as shown in FIG. 15, the ratio of the connection positions of the high-frequency power distribution bodies 32a and the connection angle (connection plate C31 or plasma) so that the connection states viewed from the direction along the current propagation path are similar to each other. Conditions such as the angle between the connection surface of the excitation electrode 4 and the direction of the axis L of the high-frequency power distribution body 32a) are set to be equal.
Specifically, as shown in FIG. 13, when the high frequency power distribution body 32a is provided so that one end of the high frequency power distribution body 32a faces the electrode center 40, the high frequency power distribution body 32a The other ends of the L-shape are set so as to be connected so as to face the same circumferential direction as the outline of the electrode 4. Moreover, as shown in FIG. 14, the T-shaped one ends of the high-frequency power distribution bodies 32a have the same angle with respect to a straight line from the electrode center 40 indicated by the broken line to the connection position of each high-frequency power distribution body 32a. -In this case, it is set to be connected in parallel.
[0079]
In addition, the high-frequency power distribution body 31 and the high-frequency power distribution body 32a are set to have the same diameter, cross-sectional shape, length, and the like, and the high-frequency power distribution bodies 31 and 32a are set to have the same high-frequency characteristics. As a result, the inductance and the high-frequency resistance of the individual high-frequency power distribution bodies 31 and 32a can be set to be equal to each other, and the currents flowing individually can be equalized. , 32a efficiently cancels the induced magnetic field at the position of the internal space, and the inductance in the power distribution section 3 can be reduced. At the same time, by equalizing the currents flowing individually, it is possible to prevent the drift of the high-frequency current to the plasma excitation electrode 4, improve the distribution of the plasma generated in the plasma generation space, and the in-plane direction of the substrate to be processed in the plasma processing It is possible to prevent the distribution of processing in.
Further, since the high-frequency power distribution body 31 and the high-frequency power distribution body 32a are rigid bodies whose shapes are set so as to maintain rigidity, inductance, high-frequency resistance, etc. in these high-frequency power distribution bodies 31, 32a, etc. Each of the high frequency characteristics can be stabilized. This prevents variations in plasma processing that may occur due to changes in the plasma processing apparatus over time as the plasma processing progresses, and makes it possible to perform uniform and stable plasma processing over time. When plasma processing is performed, each time the plasma processing is repeated, each plasma processing result can be stabilized.
Further, by making the arrangement of the high-frequency power distribution body 31 and the high-frequency power distribution body 32a symmetrical with respect to the electrode center 40 as described above, the occurrence of drift in the high-frequency current can be prevented, and the plasma generated in the plasma generation space can be prevented. The distribution of the processing can be improved and the distribution of the processing in the in-plane direction of the substrate in the plasma processing can be prevented.
[0080]
The surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31 are provided with a low resistance portion RL made of a low-resistance material compared to the center portion, so that the high-frequency power distribution bodies 31 and 32a and the connection are connected due to the skin effect. With respect to the high-frequency current flowing only in the vicinity of the surface of the plate C31, it is possible to further reduce the high-frequency resistance in the portion where the high-frequency current propagates. As a result, the high-frequency resistance can be minimized without depending on the shapes such as the thickness and length of the high-frequency power distributors 31 and 32a and the connection plate C31, and the loss of the high-frequency power supplied to the plasma generation space is further reduced. It becomes possible.
[0081]
The low resistance portion RL is a low resistance material such as Au, Ag, Cu when the base material (center portion) of the high frequency power distribution bodies 31, 32a and the connection plate C31 is made of Al, stainless steel, or the like. And alloys containing these can be applied. Further, the low resistance portion RL is provided only on the entire surface of the high-frequency power distribution bodies 31 and 32a, the entire front and back surfaces of the connection plate C31, or a part thereof, for example, a preferable location when set as a high-frequency current propagation path. It is also possible.
As an example of such a configuration, as shown in FIG. 28, the high-frequency power distribution bodies 31 and 32a are provided with a low resistance portion on the entire surface, although not shown, and at the same time, in the connection body C31, the high-frequency power distribution body 31 A low resistance portion RL is provided on the entire surface of the high frequency power supply side (output terminal PR side described later) and the side surface to be connected, and each high frequency is provided on the electrode side surface to which the high frequency power distribution body 32a is connected. The low resistance portion RL may not be provided on the center C30 side from the position where the power distribution body 32a is connected, and the low resistance portion RL may be provided on the outer side, that is, on the edge side, from the position where each high frequency power distribution body 32a is connected. As a result, when the high frequency current flows along the skin effect, the low resistance portion is provided only on the surface portion having a large influence on the high frequency current.
As examples of the above, as described later, the equilateral triangle T shown in FIG. 4, the equilateral triangles T1 to T3 shown in FIG. 19, the square Q as shown in FIG. 9, the regular pentagon QUA as shown in FIG. Alternatively, the low resistance portion is not provided on the inner side of the polygon formed by connecting the connecting positions of the high frequency power distribution bodies 32a formed at the apexes of the regular hexagon,. It is possible.
[0082]
In addition, when a low resistance portion made of a low corrosive material such as Au, Ag, or an alloy containing these is provided on the entire surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31, the plasma processing is performed. Suppressing the occurrence of changes over time such as resistance increase and other alterations due to heat generation, corrosion, oxidation, etc. due to high frequency current, and the base material and the low resistance portion of the high frequency power distribution bodies 31 and 32a and the connection plate C31. It is possible to protect, prevent a change in high frequency resistance, and stably perform plasma processing with high reproducibility.
[0083]
By setting the thickness dimension of the low resistance portion RL to be larger than the skin depth δ defined by the expression (2) with respect to the high frequency power frequency f supplied from the high frequency power source 1, Since the resistance value can be reduced, the high-frequency power supplied to the plasma generation space can be reduced by reducing the high-frequency resistance without affecting the strength of the bases of the high-frequency power distribution bodies 31 and 32a and the connection plate C31. Loss can be further reduced.
[0084]
Further, the entire surfaces of the high-frequency power distribution bodies 31 and 32a and the connection plate C31 including the surface of the low resistance portion RL are covered with an insulating coating made of an insulator, so that the high-frequency power distribution bodies 31 and 32a and the connection plate are covered. C31 can be prevented from being oxidized, and fluctuations in high-frequency resistance in the power distribution section 3 can be suppressed, and plasma processing caused by changes in high-frequency characteristics occurring in the high-frequency power distribution bodies 31 and 32a and the connection plate C31 can be prevented. It is possible to suppress fluctuation factors and perform stable plasma processing with high reproducibility. In particular, each plasma processing result can be stabilized even when performing plasma processing a plurality of times.
In the case where a low resistance portion made of a low corrosive material such as Au, Ag, or an alloy containing these is provided on the entire surfaces of the high-frequency power distribution bodies 31, 32a and the connection plate C31, an insulating coating is provided. You can not.
[0085]
Furthermore, the high-frequency power distribution bodies 31, 32a and the connection plate C31 are not deformed so that the high-frequency characteristics are changed during operation, and are not deformed before and after maintenance involving removal and assembly, and are attached at the time of attachment. Due to the fact that the position is reproducible, it is a rigid body that can cause variations in plasma processing that may occur with the passage of time in the plasma chamber 75, 76, 77 as the plasma processing progresses, particularly high frequency. It is possible to suppress the variation factor of the time-dependent change of the plasma processing due to the change in the high frequency characteristics of the power distribution bodies 31 and 32a and the connection plate C31, and to perform a uniform and stable plasma processing in time. In particular, when performing multiple plasma treatments, the plasma is Physical results to stabilize, it is possible to perform highly reproducible plasma treatment.
[0086]
The high frequency power distribution bodies 31 and 32a and the connection plate C31 are accommodated in the chassis (shielding conductor) 21 connected to the chamber wall 10 of the plasma chambers 75, 76, and 77, that is, supplied from the high frequency power source 1. Since the high frequency power distribution bodies 31 and 32a and the connection plate C31 are accommodated in the chassis 21 and the matching box 2 constituting the return path of the current path in the high frequency current, the plasma chambers 75, 76, and 77 are connected to the outside. Unnecessary radiation can be shielded, and the energy density in the small volume δV is reduced in the partial space where the high-frequency power propagates in the power distribution portion 3, so that the inductance is substantially reduced and the high-frequency current in the power feeding portion is reduced. Limits can be reduced. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be reduced.
As a result, it is possible to increase the effective high frequency power consumed in the plasma generation space.
[0087]
In the plasma processing apparatus 71 of the present embodiment, each of the plurality of plasma chambers 75, 76, 77 is configured by individually setting the electrical high frequency characteristics such as the impedance and the high frequency resistance of the power distribution body portion 3. It is possible to reduce the electrical high-frequency machine difference between the plasma chambers 75, 76, 77 of each of the plasma chambers, and to reduce the difference between the individual plasma chambers while reducing the loss of effective power consumed in the plasma space. Can be reduced.
As a result, the same process recipe is applied to the plurality of plasma chambers 75, 76, 77 to obtain substantially the same plasma processing result, that is, for example, film formation is performed in the plurality of plasma chambers 75, 76, 77. When this is done, it is possible to obtain a film having substantially uniform film characteristics such as film thickness, withstand voltage, and etching rate. Specifically, in each plasma chamber 75, 76, 77, as compared with the case where a copper plate having a shape of width 50 to 100 mm, thickness 0.5 mm, and length 100 to 300 mm is used as the power feeding plate 3, The effective power consumed in the plasma space can be increased by about 50%.
[0088]
Furthermore, the high-frequency power distribution bodies 31 and 32a and the connection plate C31 are not deformed so that the high-frequency characteristics are changed during operation, and are not deformed before and after maintenance involving removal and assembly, and are attached at the time of attachment. Therefore, the operation of the plasma processing apparatus 71 is confirmed by evaluating the substrate that has been processed, the operation is evaluated, and the power distribution unit 3 is adjusted. There is no need to perform step-by-step maintenance, and in the case of new installation or adjustment / maintenance, machine differences for each plasma chamber 75, 76, 77 are reduced, process variations are substantially eliminated, and the same process recipe is used. The adjustment time required to obtain the processing result can be greatly shortened. In addition, when an inspection method based on actual film formation on the substrate 16 to be processed is employed, results for a plurality of plasma chambers 75, 76, 77 that had to be performed separately can be realized almost simultaneously. In addition, the cost of the inspection substrate necessary for the operation confirmation adjustment of the plasma processing apparatus 71 based on the evaluation of the substrate to be processed, the processing cost of the inspection substrate, the labor cost of the workers engaged in the adjustment work, etc. Costs can be significantly reduced.
[0089]
In the present embodiment, in the plasma chambers 75, 76, and 77, the substrate 16 is placed on the susceptor electrode side 8 to set the high frequency characteristics of the power distribution body portion 3 with respect to the plasma excitation electrode 4. It is also possible to accommodate the substrate 16 on the cathode electrode 4 side so as to correspond to RIE (reactive ion etching) reactive sputter etching.
[0090]
Hereinafter, a second embodiment of a plasma processing apparatus and a plasma processing system according to the present invention will be described with reference to the drawings.
[Second Embodiment]
FIG. 16 is a cross-sectional view showing a schematic configuration of the plasma processing apparatus 91 of the present embodiment.
As shown in FIG. 16, the plasma processing apparatus 91 of the present embodiment has a configuration in which a load lock chamber 93, a heat treatment chamber 99, and treatment chambers 95 and 96 are provided around a substantially rectangular transfer chamber 92. . In this apparatus, each chamber is divided by gates g1, g2, g3, and g4 with a transfer chamber 92 in which a transfer robot for transferring a substrate is installed at the center. The transfer chamber (standby chamber) 92, the heating chamber 99, and the other processing chamber units 95 and 96 are each evacuated to a high vacuum level by individual high vacuum pumps. The load lock chamber 93 is evacuated to a low vacuum level by a low vacuum pump.
[0091]
In the plasma processing apparatus 91 of the present embodiment, the constituent elements correspond to the plasma processing apparatus 71 of the first embodiment shown in FIGS. 1 to 15. The heat treatment chamber 99 corresponds to the chamber 79, the load lock chamber 93 corresponds to the loader chamber 73 and the unloader chamber 74, and the description of the portions having substantially the same configuration is omitted.
[0092]
The plasma processing chamber units (plasma chambers) 95 and 96 form different types of films corresponding to the plasma processing chamber units (plasma chambers) 75 and 76 of the first embodiment shown in FIGS. It is possible to perform such different processes, and it is also possible to perform the same process by the same process recipe, but the configuration is substantially the same.
The plurality of plasma processing chamber units (plasma chambers) 95 and 96 include a plurality of high-frequency power distribution bodies 31 and 32b to 34b in the distribution body portion 3, and the high-frequency power distribution bodies 31 and 32b to 34b. Are connected to each other by a plurality of connectors C31 to C33, and the average density per unit volume of the high-frequency power supplied from the high-frequency power source 1 to the electrode 4 from the output terminal PR side toward the electrode 4 side becomes coarse. It is set as such.
Here, the configuration of the plasma processing chamber unit 95 will be described as an example.
[0093]
17 is a cross-sectional view showing a schematic configuration of the plasma processing chamber unit (plasma chamber) of the present embodiment, FIG. 18 is a front view showing the power distribution part 3 of the plasma processing chamber unit (plasma chamber) in FIG. 17, and FIG. It is a top view which shows the electric power distribution body part 3 and the plasma excitation electrode 4 of FIG.
[0094]
The plasma processing chamber unit (plasma chamber) 95 of this embodiment is a two-frequency excitation type plasma processing chamber, and is different from the plasma processing chamber 75 of the first embodiment shown in FIGS. This is a point that supplies power to the side and a point related to the structure of the power distribution body portion 3. Other corresponding components are denoted by the same reference numerals and description thereof is omitted.
In the plasma chambers 95 and 96 of the present embodiment, in the power distribution section 3, the high-frequency power distribution bodies 31, 32 b to 34 b are connected to each other by a plurality of connection bodies C 31 to C 33, and are directed from the output terminal PR side to the electrode 4 side. Thus, the average density per unit volume of the high-frequency power supplied from the high-frequency power source 1 to the electrode 4 is set to be coarse.
[0095]
In the plasma chamber 95 of this embodiment, as shown in FIGS. 17 to 19, a susceptor shield 12 is provided around the susceptor electrode 8, and the gap between the wafer susceptor 8 and the susceptor shield 12 is around the shaft 13. The insulating means 12C made of an electrical insulator is vacuum-insulated and electrically insulated. Further, the wafer susceptor 8 and the susceptor shield 12 are configured to be movable up and down by a bellows 11. With this configuration, the distance between the plasma excitation electrode 4 and the susceptor electrode 8 can be adjusted. The susceptor electrode 8 is connected to a second high-frequency power source 27 via a power feeding plate 28 connected to the lower end of the shaft 13 and a matching circuit 25 housed in a susceptor electrode-side matching box 26 made of a conductor. ing.
[0096]
As this electric power feeding board 28, what gave the silver surface to the copper surface which has the shape of width 50-100mm, thickness 0.5mm, and length 100-300mm is used, for example, this electric power feeding board 28 is The output terminal of the tuning capacitor 31 of the matching circuit 25 to be described later and the lower end of the shaft 13 are detachably attached by connecting means such as screws.
The power feeding plate 28 is covered with a chassis 29 connected to the lower end of the support cylinder 12B of the susceptor shield 12, and the chassis 29 is connected to a shield line of a power feeding line 27 </ b> A that is a coaxial cable and is grounded together with the matching box 26. . Thereby, the susceptor shield 12, the chassis 29, and the matching box 29 are at the same potential in terms of DC.
[0097]
Here, the matching circuit 25 is intended to match the impedance between the second high-frequency power source 27 and the susceptor electrode 8, and the matching circuit 25 includes a plurality of passive elements as shown in FIG. A tuning coil 30 and a tuning capacitor 31 are provided in series between the second high-frequency power source 27 and the power supply plate 28, and a load capacitor 32 is connected in parallel with these, and one end of the load capacitor 32 is a matching box. 26, and has substantially the same configuration as the matching circuit 2A. The matching box 26 is set to the ground potential via the shield line of the feeder line 27A, and at the same time, one end of the load capacitor 32 is grounded. It is also possible to connect a tuning coil in series with the tuning coil 30 or to provide a load capacitor in parallel with the load capacitor 32.
[0098]
In the plasma chamber 95 of this embodiment, the substrate 16 is placed on the susceptor electrode 8, and high-frequency power is supplied from the first and second high-frequency power sources 1 and 27 to both the plasma excitation electrode 4 and the susceptor electrode 8. And a reactive gas is supplied from the gas introduction pipe 17 through the shower plate 6 into the chamber chamber 60 to generate plasma, and the substrate 16 to be processed is subjected to plasma processing such as film formation. At this time, power having a frequency of about 13.56 MHz or more, specifically, power having a frequency of 13.56 MHz, 27.12 MHz, 40.68 MHz, or the like is input from the first high-frequency power supply 1. The second high frequency power supply 27 can also be supplied with power having the same or different frequency from the first high frequency power supply 1, for example, about 1.6 MHz.
[0099]
As shown in FIG. 18, as the power distribution part 3, high-frequency power distribution bodies 31, 32 b ˜ made of rod-shaped copper each having a circular cross section and an equal shape with a diameter of 2 to 10 mm and a length of 100 to 300 mm are used. 34b is mutually connected by the some connection board (connection body) C31-C33. These high frequency power distribution bodies 31, 32b to 34b and connection plates C31 to C33 are rigid bodies.
Here, each of the connection plates C31 to C33 is a disk made of copper having a thickness smaller than that of the plasma excitation electrode 4 and the same thickness as that of the plasma excitation electrode 4, and is parallel to the plasma excitation electrode 4. Opposite the state, between the output terminal PR of the matching circuit 2A and the plasma excitation electrode 4, the connection plate C31, the connection plate C32, and the connection plate C33 are provided in multiple stages so that the radial dimension increases in this order.
Here, that the connection plates C31 to C33 are similar to the plasma excitation electrode 4 means that the contour shapes of the connection plates C31 to C3 are similar to each other when viewed from the direction along the current propagation path (i-axis direction). Means.
[0100]
One end of the high-frequency power distribution body 31 is detachably attached to the output terminal of the tuning capacitor 24, which is the output terminal PR of the matching circuit 2A, by a coupling means such as screwing. The other end of the high-frequency power distribution body 31 is The connection plate (connector) C31 is connected orthogonally to the front side surface (side surface of the output terminal PR of the matching circuit 2A).
[0101]
A plurality of high-frequency power distribution bodies 32b are suspended from the back side surface (side surface of the plasma excitation electrode 4) of the connection plate C31, and the other end of the high-frequency power distribution body 32b is the front side surface of the connection plate C32 (of the matching circuit 2A). It is orthogonally connected to the output terminal PR side surface. A plurality of high-frequency power distribution bodies 33b are vertically connected to one end of the back side surface (plasma excitation electrode 4 side surface) of the connection plate C32, and the other end of these high-frequency power distribution bodies 33b is the front side surface of the connection plate C33 ( It is orthogonally connected to the output terminal PR side surface of the matching circuit 2A. A plurality of high-frequency power distribution bodies 34b are vertically connected to one end of the back side surface (side surface of the plasma excitation electrode 4) of the connection plate C33, and the other end of these high-frequency power distribution bodies 34b is orthogonal to the surface of the plasma excitation electrode 4 Connected. These high-frequency power distribution bodies 31, 32 b to 34 b are provided in parallel with the i-axis in the current propagation direction from the output terminal PR to the plasma excitation electrode 4, which is orthogonal to the plasma excitation electrode 4.
[0102]
In the high frequency power distribution bodies 31, 32b to 34b of the present embodiment, the average density per unit volume of the high frequency power supplied from the high frequency power source 1 to the plasma excitation electrode 4 from the output terminal PR side toward the electrode 4 side. Is set to be coarse. In other words, from one end of one high-frequency power distribution body 31 attached to the output terminal PR of the tuning capacitor 24 to the other end of a plurality of high-frequency power distribution bodies 34b connected to the surface of the plasma excitation electrode 4, The space where the high-frequency current is propagated in the high-frequency power distribution bodies 31 and 34b is widened so that the inductance is substantially reduced and the high-frequency resistance is reduced.
Specifically, in the first stage of the power distribution section 3, the front side surface (output terminal PR) side of the connection plate C31 is a single high-frequency power distribution body 31, and the back side surface of the connection plate C31 (front side surface of the connection plate C32). The side is made up of three high-frequency power distribution bodies 32b, and the space in which high-frequency current propagates is approximately tripled.
Further, in the second stage of the power distribution body portion 3, the high frequency power distribution body 33b on the back side surface of the connection plate C32 (the front side surface of the connection plate C33) rather than the interval between the high frequency power distribution bodies 32b on the front side surface of the connection plate C32. The space between which the high frequency current propagates is widened by setting the interval between them large.
Further, in the third stage of the power distribution part 3, the high-frequency power distribution bodies 34 b on the back side surface (plasma excitation electrode 4) of the connection plate C 33 are closer than the distance between the high-frequency power distribution bodies 33 b on the front side surface of the connection plate C 33. The space in which the high frequency current propagates is further widened by setting the interval large.
[0103]
Here, one high-frequency power distribution body 31 is connected to the center C30 position on the front side surface of the connection plate C31 (side surface of the output terminal PR of the matching circuit 2A), passes through the electrode center 40, and is plasma-excited. The electrode 4 is provided in a state parallel to the axis L perpendicular to the surface of the electrode 4, that is, coincident with the axis L.
The three high-frequency power distribution bodies 32b are parallel to each other and are symmetrical with respect to the center 40 of the circular plasma excitation electrode 4 and the back side surface (side surface of the plasma excitation electrode 4) of the connection plate C31. The connection plate C32 is connected to the front side surface (side surface of the output terminal PR of the matching circuit 2A). Here, axial symmetry means spatial symmetry with respect to an axis L that passes through the electrode center 40 and is perpendicular to the surface of the plasma excitation electrode 4, that is, each high-frequency power distributor 32b is as shown in FIG. The connection position is set so that the center of the regular triangle T1, the center of the electrode 40, the center C30 of the connection plate C31, and the center C30 of the connection plate C32 coincide with each other. Yes.
[0104]
Further, the three high-frequency power distribution bodies 33b are parallel to each other and parallel to the axis L, and are symmetrical with respect to the center 40 of the circular plasma excitation electrode 4. And it is connected to the front side surface of the connection plate C33. Here, the axial symmetry means that it is spatially symmetrical with respect to the axis L passing through the electrode center 40 and perpendicular to the surface of the plasma excitation electrode 4, that is, each high-frequency power distributor 33b is as shown in FIG. Next, the connection position is set so that the center of the regular triangle T2, the center of the electrode T40, the center C30 of the connection plate C32, and the center C30 of the connection plate C33 coincide with each other. Yes.
The three high-frequency power distribution bodies 34b are parallel to each other and parallel to the axis L, and are symmetrical with respect to the center 40 of the circular plasma excitation electrode 4 in the back side surface of the connection plate C33. And connected to the plasma excitation electrode 4. Here, as shown in FIG. 19, each high-frequency power distributor 34b is located at the apex of the regular triangle T3, and the center of the regular triangle T3, the electrode center 40, and the center C30 of the connection plate C33 are respectively connected. The connection position is set to match.
[0105]
Thus, in the power distribution body part 3, the plurality of high frequency power power distribution bodies 32b to 34b are connected so that the front and back surfaces of the connection plates C31 to C33 are in a similar state, that is, respectively. The equilateral triangles T1 to T3 indicating the connection positions of the high-frequency power distribution bodies 32b to 34b in the connection plates C31 to C33 are provided in a similar state and in the same direction (with the apex directions coincident).
[0106]
Here, the length dimension in the connection surface of the connection plate C31, that is, the plurality of high-frequency power distribution bodies 32b connected to the same connection surface is set equal, and the connection surface of the connection plate C32, that is, the same connection surface is connected. The length dimensions of the plurality of high-frequency power distribution bodies 33b are set to be equal, and the length dimensions of the connection surfaces of the connection plate C33, that is, the plurality of high-frequency power distribution bodies 34b connected to the same connection surface, are set equal. Thus, the connection surfaces facing each other of the plasma excitation electrode 4 and the connection plates C31 to C33 can be in a parallel state.
[0107]
Here, the high-frequency power distribution bodies 31, 32b to 34b and the connection plates C31 to C33 are made of a rigid body, do not deform so that the high-frequency characteristics change during operation, do not deform before and after maintenance involving removal and assembly, Reproducibility of the mounting position at the time of mounting. Specifically, it is a rod-like body or plate-like body made of copper having the above dimensions, and the above-described high-frequency power distribution bodies 31, 32b to 34b and the connection plates C31 to C33 that are not deformed by a coupling means such as screws are connected. In order for the accuracy to be reproducible, they are connected to each other and to the output terminal PR and the plasma excitation electrode 4, or are connected so as not to be deformed, for example, by welding.
[0108]
On the surfaces of the high-frequency power distribution bodies 31, 32b to 34b and the connection plates C31 to C33, a central portion made of Cu is formed, similarly to the high-frequency power distribution bodies 31, 32a and the connection plate C31 of the first embodiment shown in FIG. In contrast, a low resistance portion RL made of a low resistance material such as Au or Ag is provided, and the thickness dimension of the low resistance portion RL is set larger than the skin depth at the high frequency power frequency supplied from the high frequency power source 1. Yes.
[0109]
Further, the surfaces of the high-frequency power distribution bodies 31, 32b to 34b and the connection plates C31 to C33 are covered with an insulating film made of an insulator, similarly to the high-frequency power distribution bodies 31, 32a and the connection plate C31 of the first embodiment. It will be broken.
[0110]
The plasma processing apparatus 91 having the above configuration opens the gate g0 and carries the substrate 16 into the load lock chamber 93, closes the gate g0, and exhausts the load lock chamber 93 with a low vacuum pump. The substrate 16 loaded into the load lock chamber 93 with the gates g1 and g2 opened is moved to the heat treatment chamber 99 by the transfer arm of the transfer robot in the transfer chamber 92, the gates g1 and g2 are closed, and the transfer chamber 92 and The heat treatment chamber 99 is evacuated by a high vacuum pump. Next, the substrate 16 is heat-treated, and after completion, the gates g2 and g4 are opened and the heat-treated substrate 16 is moved to the plasma chamber 95 by the transfer arm of the transfer robot in the transfer chamber 92. The substrate 16 in the plasma chamber 95 is subjected to a reaction process, and after completion, the gates g4 and g3 are opened, and the processed substrate 16 is moved to the plasma chamber 96 by the transfer arm of the transfer robot in the transfer chamber 92. The substrate 16 in the plasma chamber 96 is subjected to a reaction process. After completion, the gates g3 and g1 are opened, and the substrate 16 is moved to the load lock chamber 93 by the transfer arm of the transfer robot in the transfer chamber 92.
[0111]
At this time, for example, the operation of each part is controlled by the control part except that the operator sets the processing conditions such as the film forming conditions in each processing chamber and the processing sequence, and the system is configured to automatically operate. Therefore, when the plasma processing apparatus 91 is used, the substrate 16 to be processed is set in the loader cassette of the load lock chamber 93 and the operator operates the start switch. The substrate 16 to be processed is transported into the processing chamber, and after a series of processes are automatically performed in each processing chamber, they are accommodated in an unloader cassette (loader cassette) by the substrate transport robot.
[0112]
In the plasma chambers 95 and 96 having the above-described configuration, the substrate to be processed 16 is placed on the susceptor electrode 8 as in the first embodiment, and high-frequency electrodes 4 and susceptor electrode 8 are respectively provided with high-frequency power from the high-frequency power sources 1 and 27. While applying power and supplying a reaction gas from the gas introduction pipe 17 through the shower plate 6 into the chamber chamber 60 to generate plasma, an amorphous silicon film, a silicon oxide film, a silicon nitride film, etc. are formed on the substrate 16 to be processed. Is deposited.
[0113]
In the plasma processing apparatus 91 of the present embodiment, the same effect as that of the first embodiment can be obtained, and in the distribution body portion (high-frequency power distribution body) 3 of each plasma chamber 95, 96, the connection plates C31 to C31. C33 is provided in multiple stages, and is set so that the maximum value of the average density per unit volume of the high-frequency power supplied from the high-frequency power source 1 from the output terminal PR side to the plasma excitation electrode 4 side becomes coarse. That is, in the plate-like space perpendicular to the i-axis, the energy of the high-frequency power in the small volume near the high-frequency power distribution body 32b is higher than the energy density of the high-frequency power in the small volume near the high-frequency power distribution body 31. The density is coarse. In addition, in the plate-like space perpendicular to the i-axis, the energy density of the high-frequency power in the minute volume near the high-frequency power distribution body 33b as compared to the energy density of the high-frequency power in the small volume near the high-frequency power distribution body 32b. Is rough. Further, in the plate-like space perpendicular to the i-axis, the energy of the high-frequency power in the small volume near the high-frequency power distribution body 34b as compared to the energy density of the high-frequency power in the small volume near the high-frequency power distribution body 33b. The density is coarse.
Thereby, the space where the high-frequency current is propagated in the high-frequency power distribution body 3 can be further expanded, and the inductance can be further reduced and the high-frequency resistance can be further reduced. As a result, the energy density in the small volume δV in the plate-like space perpendicular to the i-axis is reduced in the partial space where the high-frequency power propagates in the power distribution portion 3, and the inductance is substantially reduced. Thus, the restriction on the high-frequency current to the plasma excitation electrode 4 is reduced corresponding to the radial dimension of the three-stage connection plates C31 to C33 which are larger than the first embodiment of the connection plate C31 in the power supply portion. Can do. At the same time, in the partial space where the high frequency power propagates, the energy density in the minute volume δV is reduced, and the diameters of the three-stage connection plates C31 to C33 which are larger than those of the first embodiment of the connection plate C31. Corresponding to the direction dimension, the high frequency resistance to the plasma excitation electrode 4 is substantially reduced, and the power loss in the power feeding portion can be reduced.
As a result, the effective high frequency power consumed in the plasma generation space can be further increased.
[0114]
As a result, in this embodiment, when the same frequency is supplied, it is possible to increase the effective power consumed in the plasma space as compared with the plasma processing apparatus of one stage of the connection plate C31. When performing, it is possible to improve the plasma processing result so that the deposition rate can be improved. Thereby, when the same frequency is supplied, the connection plate C31 can further increase the effective power consumed in the plasma space as compared with the one-stage plasma processing apparatus, and the processing speed is further improved. For example, when films are stacked by plasma CVD or the like, the deposition rate can be further improved. Further, the processing speed can be further improved by increasing the plasma excitation frequency without changing the effective power consumed in the plasma space.
[0115]
Further, in the present embodiment, the plasma excitation electrode 4 includes the high-frequency power distributor 34b positioned at the apex of the equilateral triangle T3 having a large dimension with respect to the equilateral triangle T of the connecting plate C31 in the first embodiment. By connecting, high-frequency power can be supplied to the plasma excitation electrode 4 from a feeding point having a larger interval between the high-frequency power distribution bodies 34b than the interval between the one-stage high-frequency power distribution bodies 32a. For the plasma excitation electrode 4 having a large diameter, it is prevented that the plasma density is distributed in the plasma generation space due to the standing wave and the plasma processing is not uneven in the in-plane direction of the substrate to be processed. It is possible to prevent the uniformity of the film thickness and film quality within the substrate surface with respect to the substrate 16 to be processed having a larger radial dimension. That.
[0116]
Moreover, in this embodiment, the diameter dimensions, the cross-sectional shapes, and the length dimensions of the plurality of high-frequency power distribution bodies 32b to 34b connected to different connection surfaces, that is, the front side surface and the back side surface of the connection plates C31 to C33 are all. By setting them equally, it is possible to easily set the high-frequency characteristics at each stage when the high-frequency power distribution bodies 31, 32b to 34b and the connection plates C31 to C33 are connected to a plurality of stages.
[0117]
In the present embodiment, when the high-frequency power distribution bodies 32b to 34b in each stage are connected to the connection plates C31 to C33, the regular triangles T1 to T3 are connected in the same direction as shown in FIG. As shown in FIG. 20, it is possible to connect so that the centers of the equilateral triangles T1 = T3 overlap with the electrode center 40 and the angles do not coincide with each other.
The connection state of the high-frequency power distribution body 32b connected to the front side surface of the second-stage connection plate C32 and the connection state of the high-frequency power distribution body 33b connected to the front side surface of the third-stage connection plate C33 Can be different. For example, as shown in FIG. 21, it is also possible to arrange the high frequency power distribution body 32b at the apex of the regular triangle T1, and arrange the high frequency power distribution body 33b at the apex of the regular hexagon S2.
[0118]
Further, instead of the type having parallel plate type electrodes 4 and 8, plasma processing apparatuses such as ICP (inductive coupled plasma) inductively coupled plasma excitation type, RLSA (radial line slot antenna) radial line slot antenna type, RIE ( It can also be applied to a processing apparatus for reactive sputter etching.
In addition, it is also possible to perform sputtering as plasma processing by attaching a target material instead of the electrodes 4 and 8.
[0119]
Hereinafter, a third embodiment of a plasma processing apparatus and a plasma processing system according to the present invention will be described with reference to the drawings.
[Third Embodiment]
FIG. 22 is a schematic diagram showing a schematic configuration of the plasma chamber of the present embodiment.
[0120]
The plasma processing apparatus of the present embodiment has substantially the same configuration as that of the first embodiment shown in FIGS. 1 to 15 and differs from the first embodiment shown in FIGS. 1 to 15 in that a plasma processing chamber unit. This is only the positional relationship between the chamber and the matching box in the (plasma chamber) and the point relating to the power distribution part 3, and the configuration as the plasma processing apparatus is the same as in the first embodiment. In addition, substantially the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.
[0121]
Also in the present embodiment, the configuration of the plasma chamber 75 will be described as an example.
The plasma chamber 75 is provided with a plasma excitation electrode (electrode) 4 and a shower plate 5 connected to the high frequency power source 1 at an upper position of a chamber chamber (plasma processing chamber) 60, and the plasma excitation electrode 4 is connected to the chamber wall 10. Although being covered by the chassis 21, the matching circuit 2 </ b> A and the matching box 2 in which the matching circuit 2 </ b> A is accommodated are provided at positions separated from the upper position of the chamber chamber 60.
[0122]
The plasma excitation electrode 4 and the output terminal PR of the matching circuit 2A are connected by the power distribution part 3, and the power distribution part (high frequency power distribution body) 3 is directed from the output terminal PR side to the plasma excitation electrode 4 side. The maximum value of the average density per unit volume of the high-frequency power supplied from the high-frequency power source 1 is set to be coarse, and the power distribution body portion 3 in this embodiment is a housing (shielding conductor) 21A made of a conductor. Housed inside,
[0123]
The housing 21A is connected to the chassis (shielding conductor) 21 and the matching box (shielding conductor) 2, and the matching box 2 is connected to the shield line (outer conductor) of the feeder 1A that is a coaxial cable. This shielded wire is grounded in a DC manner. As a result, the susceptor electrode 8, the shaft 13, the bellows 11, the chamber bottom 10A, the chamber wall 10, the chassis 21, the housing 21A, and the matching box 2 are set to the ground potential, and at the same time, one end of the load capacitor 22 is also DC. Will be grounded.
The chamber wall 10, the housing 21A, the chassis 21, the matching box 2, and the shield wire of the feeder line 1A are respectively paths through which the high-frequency current i supplied from the high-frequency power source 1 returns to the high-frequency power source 1 side. It constitutes the return path.
[0124]
The housing 21A is provided so as to cover the power distribution body portion 3 so as to block unnecessary radiation from the power distribution body portion 3 to the outside, and for connecting the power distribution body portion 3 provided in the chassis 21 and the matching box 2. It is provided so as to cover the hole.
[0125]
In the plasma chamber 75 of the present embodiment, the high-frequency power distributors 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ are connected to each other by a plurality of connectors C31, C32 ′ in the distributor part 3. The average density per unit volume of the high frequency power supplied from the high frequency power source 1 to the electrode 4 from the output terminal PR side toward the electrode 4 side is set to be coarse.
Specifically, in the power distribution part 3, as shown in FIG. 22, the high-frequency power power distribution body 31 made of rod-like copper having a circular shape with an equal cross-section and a warp dimension of 2 to 10 mm and a different length dimension of 100 to 300 mm. , 32c, 32c ′, 32c ″ are connected to a connecting plate (connector) C31, and are made of rod-shaped copper having an equal cross-sectional circular shape with warp dimensions of 2 to 10 mm and different length dimensions of 100 to 300 mm. The high frequency power distribution bodies 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ are connected to the connection body C32 ′. These high frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ', 33c' and the connection plates C31, C32 'are rigid bodies.
[0126]
The connection plate C31 is a disk made of copper which is smaller than the plasma excitation electrode 4 and is in a similar state, and the connection plate C32 ′ is a copper plate having the same thickness as the connection plate C31 and is smaller than the plasma excitation electrode 4 and this plasma excitation electrode. 4 has an outline shape similar to an elliptical outline which is a projection figure projected onto a plane intersecting the axis L at an angle of 45 °. Further, the connection plate C31 is disposed in a state orthogonal to the plasma excitation electrode 4, and the connection plate C32 'is disposed so as to form 45 ° with respect to the plasma excitation electrode 4 and the connection plate C31. These connection bodies C31 and C32 ′ are provided in multiple stages between the output terminal PR side of the matching circuit 2A and the plasma excitation electrode 4 side so that the radial dimension of the contour shape increases in the order of the connection plate C31 and connection plate C32 ′. It has been.
[0127]
Here, the i-axis that is the propagation direction of the current from the output terminal PR to the electrode 4 in the power distribution section 3 is set in a direction perpendicular to the connection plate C31 on the output terminal PR side of the connection plate C32 ′. The direction perpendicular to the plasma excitation electrode 4 is set closer to the plasma excitation electrode 4 than the plate C32 ′. As a result, the contour shapes viewed from the direction along the current propagation path (i-axis direction) in the connection plates C31 and C32 'are similar to the plasma excitation electrode 4, respectively.
[0128]
One end of the high-frequency power distribution body 31 is detachably attached to the output terminal of the tuning capacitor 24, which is the output terminal PR of the matching circuit 2A, by a coupling means such as screwing. The other end of the high-frequency power distribution body 31 is The connection plate (connection body) C31 is orthogonal to the front side surface (side surface of the output terminal PR of the matching circuit 2A) and is connected to the center C30 position of the connection plate C31.
[0129]
A plurality of high frequency power distribution bodies 32c, 32c '.. Are arranged on the back side surface (side surface of the plasma excitation electrode 4) of the connection plate C31 so as to be orthogonal to the back side surface. 32c ″ is connected at one end, and the other ends of these high-frequency power distribution bodies 32c, 32c′.32c ″ are connected to the front side surface of the connection plate C32 ′ (side surface of the output terminal PR of the matching circuit 2A) by 45 °. Has been. One end of a plurality of high-frequency power distribution bodies 33c, 33c ′, 33c ″ forms a 45 ° angle with the back side surface of the connection plate C32 ′ on the back side surface (side surface of the plasma excitation electrode 4) of the connection plate C32 ′. The body 32c, 32c'.32c "is orthogonally connected to the high frequency power distribution bodies 33c, 33c '. The other end of 33c ″ is connected orthogonally to the surface of the plasma excitation electrode 4. These high frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ are all plasma excitation electrode 4. Is provided in parallel with the i-axis in the direction of current propagation from the output terminal PR to the plasma excitation electrode 4, which is in a direction orthogonal to the direction of the current.
[0130]
In the high frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ of the present embodiment, from the high frequency power source 1 to the plasma excitation electrode 4 from the output terminal PR side toward the electrode 4 side. The average density per unit volume of the high-frequency power supplied is set to be coarse. In other words, from one end of one high-frequency power distribution body 31 attached to the output terminal PR of the tuning capacitor 24, a plurality of high-frequency power distribution bodies 33c, 33c ′, 33c ″ connected to the surface of the plasma excitation electrode 4 Toward the other end, the space in which the high-frequency power distribution bodies 31, 33c, 33c ', 33c "propagate high-frequency currents is expanded, the inductance is substantially reduced, and the high-frequency resistance is reduced. ing.
Specifically, in the first stage of the power distribution section 3, the output terminal PR side has one high-frequency power distribution body 31, and the back side of the connection plate C31 has three high-frequency power distribution bodies 32c, 32c ′, 32c ″. Thus, the space in which the high-frequency current propagates is about three times. In addition, in the second stage of the power distribution portion 3, the high-frequency power distribution bodies 32c, 32c ′, 32c ″ on the front side surface of the connection plate C32 ′. The space between the high-frequency power distribution bodies 33c, 33c ', 33c "on the back side surface of the connection plate C32' is set larger than the space between them, and the space in which the high-frequency current propagates is expanded.
[0131]
Here, one high frequency power distribution body 31 is connected to the center C30 position on the front side surface (side surface of the output terminal PR of the matching circuit 2A) of the connection plate C31, and passes through the center C30 to connect the connection plate C31. Are provided in parallel with an axis L ′ perpendicular to the front side surface, that is, coincident with this axis L ′.
The three high-frequency power distribution bodies 32c, 32c ′, 32c ″ are parallel to each other and are symmetrical with respect to the center C30 of the circular connection plate C31. The electrode 4 side surface) and the front side surface of the connection plate C32 (side surface of the output terminal PR of the matching circuit 2A) are connected to each other, and the axis symmetry means that it passes through the center C30 of the connection plate C31 and is perpendicular to the surface of the connection plate C31. Spatial symmetry with respect to the axis L ′, that is, the respective high-frequency power distribution bodies 32c, 32c ′, 32c ″ are equilateral triangles in the connection plate C31 as in the second embodiment shown in FIG. The connection position is set so that the center of the regular triangle T1, the center C30 of the connection plate C31, and the center C30 of the connection plate C32 coincide with each other at the vertex of T1.
[0132]
Further, the three high-frequency power distributors 33c, 33c ′, 33c ″ are parallel to each other and parallel to the axis L passing through the center 40 of the plasma excitation electrode 4 and perpendicular to the plasma excitation electrode 4. Are connected to the back side surface of the connection plate C32 ′ and the surface of the plasma excitation electrode 4 in an axially symmetric state with respect to the center 40 of the plasma excitation electrode 4. Here, the axial symmetry means that the plasma passes through the electrode center 40 and the plasma. Spatial symmetry with respect to the axis L perpendicular to the surface of the excitation electrode 4, that is, the high-frequency power distributors 33c, 33c ′, 33c ″ correspond to the second embodiment shown in FIG. The connection position is set so that the center of the regular triangle T2, the electrode center 40, and the center C30 of the connection plate C32 ′ coincide with each other at the apex of the regular triangle T2 in the plasma excitation electrode 4.
Here, the axis L and the axis L ′ intersect at the center C30 of the connection plate C32 ′ and are orthogonal to each other.
[0133]
Here, the high frequency power distribution bodies 32c, 32c ′, 32c ″ and the high frequency power distribution bodies 33c, 33c ′, 33c ″ are connected so that the front surface and the back surface of the connection plate C32 ′ are similar to each other. That is, the equilateral triangles T1 and T2 indicating the connection positions of the high-frequency power distributors 31, 32c, 32c ′, 32c ″, 33c, 33c ′, and 33c ″ on the connection plate C31 and the plasma excitation electrode 4 are in a similar state and in the same direction. (It is set so that the directions of the vertices match.)
[0134]
Here, the high frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ and the connection plates C31, C32 ′ are made of a rigid body, and are not deformed so that the high frequency characteristics change during operation. It does not deform before and after maintenance involving removal and assembly, and has reproducibility of the mounting position at the time of mounting. Specifically, it is a rod-like body or plate-like body made of copper having the above dimensions, and is not deformed by the above-described high-frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ and the connection plates C31 and C32 ′ are connected to each other and to the output terminal PR and the plasma excitation electrode 4 so that the accuracy of the connection state is reproducible or not deformed by welding or the like, for example. It is connected to the.
[0135]
The high-frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ and the connection plates C31, C32 ′ have high-frequency power distribution bodies 31, 32a according to the first embodiment shown in FIG. Similarly to the connection plate C31, a low resistance portion RL made of a low resistance material such as Au or Ag is provided compared to the central portion made of Cu, and the thickness dimension of the low resistance portion RL is supplied from the high frequency power source 1. It is set to be larger than the skin depth at the high frequency power frequency.
[0136]
Furthermore, the high frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ and the connection plates C31, C32 ′ and the connection plates C31, C32 ′ of the first embodiment are connected to the high frequency power distribution bodies 31, 32c, 32c ′, 32c ″. Like C31, it is covered with an insulating film made of an insulator.
[0137]
The plasma processing apparatus 71 of this embodiment has the same effects as those of the first and second embodiments, and the power distribution portion (high frequency power distribution body) 3 of each plasma chamber 75, 76, 77 has a high frequency power. The power distribution bodies 31, 32 c, 32 c ′, 32 c ″, 33 c, 33 c ′, 33 c ″ and the connection plates C 31, C 32 ′ are the housing 21 A as the shielding conductor connected to the chamber wall 10 of the chamber chamber 60, the chassis 21 and the matching. The matching circuit is formed by being covered with the box 2 and being housed therein, that is, the distribution body portion 3 is located inside the shielding conductor constituting the return path of the high-frequency current path supplied from the high-frequency power source 1. Without damaging the flexibility of the installation location of 2A, it can block unnecessary radiation to the outside like a coaxial cable, In subspace propagation of high-frequency power, it can result in a reduction in the energy density of symptom small volume .DELTA.V, to reduce substantially inductance reduces the restrictions on the high-frequency current at the feeding portion. At the same time, the energy density in the small volume δV is reduced in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be reduced.
As a result, the effective high-frequency power consumed in the plasma generation space can be increased, that is, the power supply portion is shielded regardless of the positional relationship among the matching circuit 2A, the plasma excitation electrode 4 and the chamber chamber 60. Can be performed.
[0138]
In addition, in the power distribution part 3 of the present embodiment, the connection plates C31 and C32 ′ are composed of two stages. However, the connection plates C31 and C32 ′ can be multi-staged and can be configured with only one stage of the connection plate C32 ′. It is. Further, the power distribution body portion 3 can be formed in a U shape or other shapes besides the generally L shape.
Further, the connection plate C32 ′ and the high-frequency power distribution bodies 31, 32c, 32c ′, 32c ″, 33c, 33c ′, 33c ″ are configured to make 45 °, but this also makes an arbitrary angle. Can do.
[0139]
In addition, it is possible to apply the power distribution part 3 of this embodiment in place of the power feeding plate 28 in the second embodiment shown in FIG.
Further, instead of the type having parallel plate type electrodes 4 and 8, plasma processing apparatuses such as ICP (inductive coupled plasma) inductively coupled plasma excitation type, RLSA (radial line slot antenna) radial line slot antenna type, RIE ( It can also be applied to a processing apparatus for reactive sputter etching.
[0140]
Furthermore, although the plasma processing apparatus in each of the above embodiments has a configuration having a plurality of plasma processing chamber units (plasma chambers), it may be configured by a single unit.
[0141]
Hereinafter, a fourth embodiment of a plasma processing apparatus and a plasma processing system according to the present invention will be described with reference to the drawings.
[Fourth Embodiment]
FIG. 23 is a schematic diagram showing a schematic configuration of the plasma processing system of the present embodiment.
[0142]
The plasma processing system of the present embodiment includes plasma processing apparatuses 71 and 71 ′ substantially equivalent to the first and third embodiments shown in FIG. 1, and a plasma processing apparatus substantially equivalent to the second embodiment shown in FIG. 91 and a schematic configuration. Components corresponding to those of the first to fourth embodiments described above are denoted by the same reference numerals, and description thereof is omitted.
[0143]
As shown in FIG. 23, the plasma processing system of the present embodiment includes a plasma processing apparatus 71 having three plasma processing chamber units (plasma chambers) 95, 96, and 97, two plasma processing chamber units (plasma chambers) 95, A plasma processing apparatus 91 having 96 and a plasma processing apparatus 71 ′ having three plasma processing chamber units (plasma chambers) 95, 96, 97 constitute a part of the production line.
Here, in the portions of the plasma processing apparatuses 71 and 71 ′ of the first and third embodiments as shown in FIG. 1, instead of the plasma processing chamber units (plasma chambers) 75, 76 and 77, shown in FIG. In the second embodiment, three plasma processing chamber units (plasma chambers) 95 and 96 that are substantially the same as the two-frequency excitation type plasma processing chamber unit (plasma chamber) 95 are provided. 97 have substantially the same structure.
[0144]
In the plasma processing system of this embodiment, as shown in FIG. 23, the impedance measurement terminals for the plasma chambers 95, 96, and 97 are connected to the impedance measuring instrument AN via the switch SW3. The switch SW3 connects only the plasma chambers 95, 96, 97 to be measured and the impedance measuring instrument AN when measuring the plasma chambers 95, 96, 97, and disconnects the other plasma chambers 95, 96, 97. It is provided as a switch for switching.
[0145]
In the present embodiment, the plasma excitation electrodes 4 of the plurality of plasma chambers 95, 96, and 97 and the output terminal PR of the matching circuit 2A are connected by the power distribution portion 3 and this power distribution portion (high-frequency power distribution body). 3 is set so that the maximum value of the average density per unit volume of the high-frequency power supplied from the high-frequency power source 1 from the output terminal PR side toward the plasma excitation electrode 4 side becomes coarse. The body part 3 is covered with a housing (shielding conductor) 21A and / or a chassis 21 and a matching box 2 made of a conductor, and is housed inside these.
[0146]
In the plasma processing system of the present embodiment, for example, film formation is performed in the plasma chambers 95, 96, and 97 of the plasma processing apparatus 71 on the substrate 16 that has been subjected to the plasma processing pre-processing, and then in the heat treatment chamber 79. Heat treatment is performed, and then annealing treatment is performed in the laser annealing chamber 78. Next, the substrate 16 to be processed is unloaded from the plasma processing apparatus 71, and second and third film forming processes are sequentially performed on the substrate 16 to be processed in a plasma processing chamber in an apparatus equivalent to the plasma processing apparatus 71 (not shown).
Next, a photoresist is formed on the substrate 16 to be processed unloaded from the plasma processing apparatus by a photolithography process in another processing apparatus (not shown).
Then, the substrate 16 to be processed is carried into the plasma processing apparatus 91 and plasma etching is performed in the plasma chambers 95 and 96.
Next, the resist is peeled off from the processing target substrate 16 unloaded from the plasma processing apparatus (not shown) in another processing apparatus (not shown).
Finally, first, second, and third film forming processes are sequentially performed on the target substrate 16 in the plasma chambers 95, 96, and 97 of the plasma processing apparatus 71 ′, and the target substrate 16 is subjected to a post-plasma processing process. The process in the plasma processing system of the present embodiment in the production line is completed.
[0147]
In the plasma processing system of the present embodiment, the same effects as those of the first to third embodiments can be obtained, and the plasma excitation electrode 4 of the plasma chambers 95, 96, and 97 and the output terminal PR of the matching circuit 2A are each distributed. The power distribution part (high-frequency power distribution body) 3 is connected by the body part 3 and is an average per unit volume of the high-frequency power supplied from the high-frequency power source 1 from the output terminal PR side toward the plasma excitation electrode 4 side. Since the maximum value of the density is set to be coarse, in each plasma chamber 95, 96, 97, the energy density in the partial space in which the high frequency power propagates is further reduced, the inductance is substantially reduced, and the high frequency is reduced. In the partial space where the high frequency power propagates in the power feeding portion from the high frequency power source 1 to the plasma excitation electrode 4, the resistance further decreases. There are, results in a reduction in the energy density of symptom small volume .DELTA.V, to reduce substantially inductance, it is possible to further reduce the limit for high-frequency current at the feeding portion. At the same time, the energy density in the small volume δV decreases in the partial space in which the high-frequency power propagates, so that the high-frequency resistance is substantially reduced and the power loss in the power feeding portion can be further reduced.
As a result, it is possible to increase the effective high-frequency power consumed in the plasma generation space, and reduce the loss of high-frequency power in the plurality of plasma chambers 95, 96, 97, so that the plasma processing system as a whole can be reduced. It becomes possible to further reduce the loss of high-frequency power.
[0148]
In addition, it is possible to reduce the difference in electrical and high-frequency characteristics for the plasma chambers 95, 96, and 97, so that the plasma processing system as a whole can have a plurality of differences within a certain management range using the impedance characteristics as an index. It is possible to set the state of the plasma chambers 95, 96, and 97, so that the plasma density generated in the individual plasma chambers 95, 96, and 97 can be made substantially uniform. Thus, the same process recipe is applied to the plurality of plasma chambers 95, 96, 97 in the entire plasma processing system to obtain substantially the same plasma processing result, that is, the plurality of plasma chambers 95, 96, 97 are obtained. For example, when film formation is performed, it is possible to obtain a film having substantially uniform film characteristics such as film thickness, withstand voltage, and etching rate. Therefore, the stability of plasma generation in the individual plasma chambers 95, 96, and 97 can be expected by setting the general electrical and high frequency characteristics of the plasma processing system. As a result, it is possible to provide a plasma processing system that has high operational stability and can be expected to operate uniformly in each of the plasma chambers 95, 96, and 97.
[0149]
In addition, when the same frequency is supplied, it is possible to improve the effective power consumed in the plasma space as compared with the conventional plasma processing system, so the power consumption efficiency of the plasma processing system as a whole is improved. In order to obtain the same processing speed or film characteristics, less input power can be used than before. In addition, these can be realized in a plurality of plasma chambers 95, 96, 97. Therefore, it becomes possible to further reduce the power loss of the entire plasma processing system, reduce the running cost, and improve the productivity. At the same time, since the processing time can be further shortened, the power consumption required for the plasma processing can be reduced, so that the total amount of carbon dioxide that is an environmental load can be further reduced.
[0150]
Further, instead of the type having parallel plate type electrodes 4 and 8, plasma processing apparatuses such as ICP (inductive coupled plasma) inductively coupled plasma excitation type, RLSA (radial line slot antenna) radial line slot antenna type, RIE ( It can also be applied to a processing apparatus for reactive sputter etching.
[0151]
【The invention's effect】
According to the plasma processing apparatus and the plasma processing system of the present invention, in the high-frequency power distribution body, an average per unit volume of the high-frequency power supplied from the high-frequency power source to the electrode from the output terminal side toward the electrode side By setting the density to be coarse, the space in which the high-frequency current propagates in the high-frequency power distribution body is expanded, and the high-frequency power supplied to the plasma generation space is substantially reduced by reducing the high-frequency resistance and inductance. The effect that it becomes possible to reduce the loss of electric power can be produced.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration in a first embodiment of a plasma processing apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing a schematic configuration of a plasma processing chamber unit (plasma chamber) in the first embodiment of the plasma processing apparatus according to the present invention.
3 is a perspective view showing a power distribution portion 3 of the plasma processing chamber unit (plasma chamber) in FIG. 2. FIG.
4 is a plan view showing a power distribution section 3 and a plasma excitation electrode 4 of FIG.
FIG. 5 is a cross-sectional view for explaining a low resistance portion RL and a skin depth δ of the high frequency power distributors 31 and 32a and the connection plate C31.
6 is a longitudinal sectional view showing a laser annealing chamber in FIG. 1. FIG.
7 is a longitudinal sectional view showing a heat treatment chamber in FIG. 1. FIG.
FIG. 8 is a plan view showing another embodiment of the high-frequency power distributor and connecting plate according to the present invention.
FIG. 9 is a plan view showing another embodiment of the high-frequency power distributor and connecting plate according to the present invention.
FIG. 10 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 11 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 12 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 13 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 14 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 15 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 16 is a schematic block diagram showing a second embodiment of the plasma processing apparatus according to the present invention.
FIG. 17 is a cross-sectional view showing a schematic configuration of a plasma processing chamber unit (plasma chamber) in the second embodiment of the plasma processing apparatus according to the present invention.
18 is a front view showing a power distribution portion 3 of the plasma processing chamber unit (plasma chamber) in FIG. 17. FIG.
19 is a plan view showing a power distribution portion 3 and a plasma excitation electrode 4 in FIG.
FIG. 20 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 21 is a plan view showing another embodiment of the high-frequency power distributor and the connecting plate according to the present invention.
FIG. 22 is a cross-sectional view showing a schematic configuration of a plasma processing chamber unit (plasma chamber) in the third embodiment of the plasma processing apparatus according to the present invention.
FIG. 23 is a schematic diagram showing a schematic configuration in a fourth embodiment of a plasma processing system according to the present invention.
FIG. 24 is a perspective view for explaining the propagation state of high-frequency power in the present invention and a schematic graph showing power energy density.
FIG. 25 is a perspective view for explaining the propagation state of high-frequency power in the present invention and a schematic graph showing power energy density.
FIG. 26 is a schematic view showing an example of a conventional plasma processing apparatus.
FIG. 27 is a schematic view showing another example of a conventional plasma processing apparatus.
FIG. 28 is a front view showing a configuration in which a low resistance portion in the power distribution portion is partially provided in the embodiment according to the invention.
FIG. 29 is a front view showing a configuration in which a low resistance portion in the power distribution portion is partially provided in the embodiment according to the invention.
[Explanation of symbols]
1 ... High frequency power supply
1A, 27A ... feeder line (high frequency power feeder)
2. Matching box (shielding conductor)
2A, 25 ... matching circuit
3. Distribution part (high frequency power distribution body)
C31-C33, C32 '... connection plate (connector)
4 ... Plasma excitation electrode (cathode electrode)
5 ... Shower plate
6 ... space
7 ... hole
8 ... Wafer susceptor (susceptor electrode)
9: Insulator
10 ... Chamber wall
10A ... bottom of chamber
11 ... Bellows
12 ... susceptor shield
12A ... Shield support plate
12B ... support cylinder
13 ... Shaft
16 ... Substrate (substrate to be processed)
17 ... Gas introduction pipe
17a ... insulator
21 ... Chassis (shielding conductor)
21A ... Housing (shielding conductor)
22, 32 ... Load capacitors
23, 30 ... Tuning coil
24, 31 ... tuning capacitors
26 ... Matching box
27. Second high frequency power supply
28 ... Feed plate (high frequency power distribution body)
29 ... Chassis
31, 32a, 32b to 34b, 32c, 32c ', 32c ", 33c, 33c', 33c" ... high frequency power distribution body
60 ... Chamber room (plasma processing room)
71, 91 ... Plasma processing apparatus
72, 92 ... transfer chamber
73 ... Loader room
74 ... Unloader room
75, 76, 77, 95, 96, 97 ... Plasma chamber (plasma processing chamber unit)
78 ... Laser annealing chamber
79,99 ... Heat treatment room
80, 84 ... chamber
81 ... Laser light source
82 ... Stage
83 ... Laser light
85 ... Heater
86 ... Gate valve
87. Substrate transfer robot (transfer means)
88 ... arm
93 ... Load lock room

Claims (20)

A plasma processing chamber having electrodes for exciting the plasma;
A high frequency power source for supplying high frequency power to the electrode;
An input terminal and an output terminal, the high-frequency power source is connected to the input terminal via a high-frequency power feeder, and the electrode is connected to the output terminal via a high-frequency power distributor; A plasma processing chamber unit having a matching circuit for obtaining impedance matching with a high-frequency power source,
In the high-frequency power distribution body, the average density per unit volume of the high-frequency power supplied from the high-frequency power source to the electrode from the output terminal side toward the electrode side is set to be rough ,
The high-frequency power distribution body consists of a plurality of wires,
The plurality of high-frequency power distribution bodies are provided in parallel with each other,
The plurality of high-frequency power distribution bodies are connected to the electrodes in an axially symmetric state with respect to the center of the electrodes;
The plurality of high-frequency power distribution bodies are connected to each other by a connection body,
The plasma processing apparatus , wherein the connection body is provided with a surface substantially parallel to the electrode . It said connection body is a plasma processing apparatus according to claim 1, characterized by being formed in a plate-like body of the electrode with similar shape. Wherein the plurality of RF feeder is the connection body center plasma processing apparatus according to claim 1 or 2, characterized in that connected to the connecting body axisymmetric state with respect to the. The plasma processing apparatus according to any one of claims 1 to 3 , wherein the plurality of high-frequency power distribution bodies are connected so that the front surface and the back surface of the connection body are in a similar state. It said connection body is a plasma processing apparatus according to any one of 4 from claim 1 characterized by comprising provided with a plurality of the output terminal side to the electrode. Wherein the plurality of the RF feeder, the plasma processing apparatus according to claim 1, wherein the high frequency characteristics of the RF feeder is set to be equal to each other.   2. The plasma processing apparatus according to claim 1, wherein a surface of the high-frequency power distribution body is provided with a low-resistance portion made of a low-resistance material compared to the center portion. Wherein the surface of the connection member, the plasma processing apparatus according to claim 1, characterized in that the low-resistance portion made of a low resistance material is provided as compared with the center. The thickness of the low resistance portion, the plasma processing apparatus according to claim 7 or 8, wherein the composed set to be larger than the skin depth in the high-frequency power frequency supplied from the high frequency power source.   The plasma processing apparatus according to claim 1, wherein a surface of the high-frequency power distributor is covered with an insulating film made of an insulator. The surface of the connecting body, a plasma processing apparatus according to claim 1, characterized by being covered with an insulating film made of an insulating material.   The plasma processing apparatus according to claim 1, wherein the high-frequency power distribution body is made of a rigid body. The plasma processing apparatus according to claim 1, wherein said connecting member is made of a rigid body.   The plasma processing apparatus according to claim 1, wherein the high-frequency power distributor is accommodated in a shielding conductor connected to a chamber wall of the plasma processing chamber. The plasma processing apparatus according to claim 1, wherein said connecting member is housed within the shield conductor connected to the chamber wall of the plasma processing chamber. In the plasma processing apparatus in any one of Claim 1 to 15 ,
A plasma processing apparatus comprising a plurality of the plasma processing chamber units. Plasma processing system, wherein the plasma processing apparatus according to any of claims 1 to 16 is provided with a plurality.   The plasma processing apparatus according to claim 5, wherein the plurality of connecting bodies are provided in multiple stages so that a radial dimension increases from the output terminal side toward the electrode side. The plurality of connection bodies are provided in multiple stages such that a polygonal area having the plurality of high-frequency power distribution bodies as apexes increases from the output terminal side toward the electrode side. Item 6. The plasma processing apparatus according to Item 5.   The current propagation direction in the high-frequency power distribution part connected to the electrode is set in a direction perpendicular to the current propagation direction in the high-frequency power distribution part connected to the output terminal. The plasma processing apparatus according to claim 5.

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