JP3602717B2

JP3602717B2 - Multi-layer X-ray reflector

Info

Publication number: JP3602717B2
Application number: JP7833698A
Authority: JP
Inventors: 久貴竹中; 孝晏望月
Original assignee: NTT Advanced Technology Corp
Current assignee: NTT Advanced Technology Corp
Priority date: 1998-03-11
Filing date: 1998-03-11
Publication date: 2004-12-15
Anticipated expiration: 2018-03-11
Also published as: JPH11258396A

Description

【０００１】
【発明の属する技術分野】
本発明は半導体材料など各種の材料の化学状態、化学組成、不純物濃度なかでも軽元素を高感度で分析する装置に必要な軟Ｘ線を選択する分光素子や微細加工・Ｘ線顕微鏡・Ｘ線望遠鏡などに必要な高効率の多層膜Ｘ線反射鏡に関するものである。
【０００２】
【従来の技術】
様々な結像光学系において、波長が短くなると解像度が向上するために、使用光の短波長化が進められている。一方、光の波長が短くなると、特に波長が数１００ Å以下になると反射率が極端に低下しほとんど反射率は実質上零になってしまう。しかし、例えば第１図のように２種類の物質層を一定の厚みで交互に規則正しく積層させるとブラッグ回折を利用した高反射率の直入射反射鏡（多層膜反射鏡）が実現される。
【０００３】
特に波長が１３０ Åｎｍ近傍の軟Ｘ線に対してはＭｏ層とＳｉ層を数ｎｍずつ規則正しく交互に数１０層以上積層させたＭｏ／Ｓｉ多層膜では６０数％もの直入射反射率が得られるため、Ｘ線縮小露光やＸ線顕微鏡，天体望遠鏡などの反射鏡として広く利用されるようになってきた。またＸ線源としてはシンクロトロン放射光（ＳＲ）、レーザープラズマＸ線（ＬＰＸ）、ガスピンチプラズマ（ＧＰＰ）が用いられているがシンクロトロン放射光は加速器を用いた大がかりで且つ高価な装置を必要とし、ガスピンチプラズマは輝度が数桁低い光源であるため、輝度が１０^１２Ｗ／ｃｍ^２と大きく、比較的コンパクトなレーザプラズマＸ線が前記応用の実用光源として有望である。しかし、第２図に示すようにパルスレーザー光で励起されるレーザープラズマＸ線源ではターゲット材料の蒸気、微粒子の蒸発があるため、これがＸ線反射鏡を代表とするＸ線光学系に付着すればその性能を損なう。これを阻止するため反射鏡との間に機械的に同期するシャッターを挿入したり、バッファーガスを入れたり、又は反射鏡を距離的に遠くに配置したりして発生するＸ線を集光し利用に供している。しかしいずれにしても反射鏡は点源であるレーザープラズマＸ線源からは離れた場所に配置せざるを得ないため、Ｘ線の利用効率が悪いという欠点があり、その実用化が妨げられていた。一方これらの応用において更に解像度を向上させようとすると１３０ Å近傍より波長の短い軟Ｘ線を使用する必要があった。しかしながらＭｏ／Ｓｉ多層膜を波長１２４ Å以下（ＳｉのＬ吸収端以下）で使用すると直入射反射率が数〜１０数％と極端に低下し、実用上使用できなかった。そこでＭｏとＢ４Ｃなどの組み合わせの多層膜Ｘ線反射鏡の適用がはかられてきたがこれでも３０％程度の反射率しか得られず実用には適さなかった。最近、ＭｏとＢｅの層を交互に積層させた多層膜Ｘ線反射鏡が作製され、この多層膜Ｘ線反射鏡でＢｅの吸収端直上波長（１１１ Å直上）において６０％を越える直入射反射率が得られることが見出され、上記応用等において波長の短い軟Ｘ線でも高反射率を得ることにより解像度向上がはかられることが期待されるようになってきた。また最近、化学的に不活性な希ガス元素を低温にて液化又は固化した状態、又は液体に近い蒸気密度の低温ガス状態にして、これをレーザープラズマＸ線源（ＬＰＸ）のターゲット材として用い、反射鏡他のＸ線光子系へのターゲット粒子の付着を無くしたクライオターゲットが発明（特許第２６１４４５７号）されＬＰＸは実用化の道を歩み始めたと云える。
【０００４】
【発明が解決しようとしている問題】
通常、Ｘ線結像光学系では第１図のような多層膜反射鏡を複数枚使用するので一般に光学系全体ではＸ線集光・透過率が大幅に低下する。そのため反射鏡１枚当たりに少しでも高い反射率が求められている。
【０００５】
ＭｏとＢｅの組み合わせでは実際に成膜するとＭｏやＢｅが凝集するため各層の界面のあらさが大きくなり、この粗さの影響のため、理想構造での計算上の反射率に比べ２０％程度も低下する問題があった。また、Ｍｏ／Ｂｅの組み合わせでは、Ｂｅの融点が１２７０℃程度と低いため、Ｍｏ／Ｓｉ多層膜Ｘ線反射鏡と同様、高輝度の軟Ｘ線の使用や使用環境の高温化によって反射率が急激に低下し、安定に使用できないという耐熱性の問題も存在した。更にＭｏとＢｅの組み合わせの多層膜Ｘ線反射鏡では波長が１１１ Å以下になると極端に反射率が低下するため、この波長以下では使用できないという問題も存在した。一方、クライオターゲットとして典型的な例であるＸｅ（キセノン）クライオターゲットレーザープラズマＸ線源では波長１０８ Å付近にて発光スペクトル強度が最も強いことが本発明者の一人、望月により見いだされた^＊がこれらの波長で十分な反射率（５０％以上）を与える反射鏡は現在存在していない。またクライオターゲットを用いる最大の利点、即ちターゲット粒子の付着を避けられるため反射鏡を線源近傍に配置でき、大きな集光立体角を持つ集光光子系を形成出来るという利点を生かすには強力なＸ線やプラズマからの散乱レーザー光に曝されても安定に高反射率を保つ長寿命の反射鏡が必要であるが、従来の反射鏡ではこれらの要求を満たすものは無い。（^＊引用文献Ｔ．Ｍｏｃｈｉｚｕｋｉｅｔａｌ．，Ａｐｐｌ．Ｐｈｙｓ．Ｌｅｔｔ．（１９９８）Ｊａｎ．ｔｏｂｅｐｕｂｌｉｓｈｅｄ）
【０００６】
【課題を解決するための手段】
上記の目的を達成するために本発明は（１）一方の層の材料としてＲｕ、Ｒｈの一種を含む層を使用し、他の一方にＢｅ、Ｂ６Ｂｅを使用したこと、（２）一方の層の材料としてＲｕ、Ｒｈの一種を含む層を使用し、他の一方にＢｅと金属の化合物を使用したこと、（３）一方の層の材料としてＲｕあるいはＲｈと金属の化合物を含む層を使用し、他の一方にＢ、Ｂｅ、Ｂｅ化合物の一種を含む層を使用したことを特徴とする高効率、長寿命の多層膜Ｘ線反射鏡を要旨とするものである。
【０００７】
【作用】
本手段は反射率向上のためＭｏ／Ｂｅ多層膜においてＭｏの代わりにＲｈを使用した多層膜を作製し波長１１５ Åで反射率測定を行ったところ、反射率が４％向上したことに端を発する。このことはＭｏよりも光学定数が適した材料がある可能性を示していた。そこでＭｏよりもこの波長近傍では適した光学定数の材料であるＲｕ、更にＭｏとＲｕあるいはＲｈとの合金、ＲｕとＲｈの合金をＭｏの代わりに使用するとＸ線反射率は高まることになる。
【０００８】
更につけ加えると、反射率は光学定数に大きく依存するが多層膜の層界面の粗さが大きくなると得られる反射率は計算値に比べ低下する。一方、Ｂ、Ｃ、Ｏ、Ｎなどの元素を添加させた合金や金属は数ｎｍ〜数１０ｎｍの厚みの極薄層とすると通常非晶質層となり易く、非晶質になると合金や金属の単体層よりも層界面が滑らかになる。そこでこれらの元素を添加させた合金をＭｏの代わりに使用すると反射率向上の効果が出現することになる。このため一方の層にこのような物質を用い、かつ、他の一方の層にＢｅを用いた多層膜を、（１）Ｘ線・軟Ｘ線を利用した各種分析に適用した場合、多層膜の反射率がＢｅ層以外の層にＭｏ層を用いた多層膜よりも向上するため、感度や精度が向上し、（２）Ｘ線リソグラフィーに適用した場合、Ｂｅ層以外の層にＭｏを用いた多層膜よりも（１）と同様の理由でスループットの向上がはかれるようになる。
【０００９】
また、Ｂｅも含め金属にＢ、Ｃ、Ｏ、Ｎなど他元素を添加あるいは化合させた物質は一般に金属単体よりも融点が高くなることが多く、かつ、層間の拡散も抑制される。このためこれらの物質を多層膜の構成材料として用いると耐熱性が向上するのでこれらの物質を利用した多層膜を（１）Ｘ線・軟Ｘ線を利用した各種分析に適用した場合、耐熱性が従来の多層膜反射鏡よりも向上するため、使用中での反射率の変化が従来の反射鏡よりも少なくなり、精度や確度が向上する、（２）Ｘ線リソグラフィーに適用した場合は、（１）と同様の理由で適性露光時間を正確に決められるようになる、更に（３）多層膜自身の寿命が延びるなどの作用を有することになる。
【００１０】
さらに、本発明の反射鏡では１０８ Å近辺でも充分高い反射率（５０％）を得ることができるので、特にクライオターゲットを用いたレーザープラズマＸ線源用の高効率で且つ寿命の長い集光光学系が実現できるなどの作用がある。特に縮小投影リソグラフィーのスループットを実用レベルにまで向上させるなどの作用がある。またＸ線加工の速度を早くするなどの作用もある。
【００１１】
【発明の実施の形態】
以下、実施例に沿って発明の実施の形態例を説明する。
【００１２】
【参考例１】
複数個の原料ターゲットを備えたＲＦマグネトロンスパッタ装置を用い、成膜室を１０^-8Ｔｏｒｒ台に排気後、Ａｒガスを成膜室に導入して成膜室内を３×１０^-3Ｔｏｒｒの圧力のＡｒ雰囲気にした後、放電を起こし、Ｍｏ層とＢｅ層を繰り返し積層させた多層膜を作製した。Ｍｏ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。Ｍｏ層とＢｅ層の一層ずつの厚みを加えた厚み（周期長Ｄ）に対するＭｏの厚みｄＭｏを１０〜９０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を放射光利用の反射率計を用いて測定した結果を表１に示す。Ｍｏ層の厚みが周期長の５０％のとき最大の反射率を示しその値は６２％であった。また、Ｍｏ層の厚みが周期長の２０％から７０％の範囲で反射率が４０％以上と高い値を示した。
【００１３】
【表１】
【００１４】
【参考例２】
参考例１と同様にしてＮを５ａｔ．％添加したＭｏ−Ｎ層とＮを５ａｔ．％添加したＢｅ−Ｎ層を繰り返し積層させた多層膜を作製した。Ｍｏ−Ｎ層とＢｅ−Ｎ層のペアの数は４０で周期長６ｎｍのものとペアの数が８０で周期長５．６ｎｍのものを作製した。Ｍｏ−Ｎ層とＢｅ−Ｎ層の一層ずつの厚みを加えた厚みＤに対するＭｏの厚みｄＭｏ−Ｎを１０〜９０％の範囲の中で変化させた。参考例１と同様この多層膜の波長と反射率との関係を反射率計を用いて測定したところ、周期長６ｎｍのものは波長１１４Åの軟Ｘ線に対しＭｏ−Ｎ層の厚みが周期長の５０％のとき反射率６９％を示し、また、参考例１と同様、Ｍｏ−Ｎ層の厚みが周期長の２０％から７０％の範囲で反射率が４５％以上と高い値を示した。更に、周期長６ｎｍのものは波長１０８Åの軟Ｘ線に対しＭｏ−Ｎ層の厚みが周期長の５５％のとき反射率がほぼ５１％を示し、また、参考例１と同様、Ｍｏ−Ｎ層の厚みが周期長の４５％から７０％の範囲で反射率が４５％以上と１１０Å以下の波長に対しては従来に無い高い値を示した。
【００１５】
【参考例３】
参考例１と同様、スパッタ法により一つの層にＲｈを用い、他の一つの層にＢｅを使用し、これらの層構成を繰り返した多層膜を作製した。Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。Ｒｈ層とＢｅ層の一層ずつの厚みを加えた厚み（周期長Ｄ）に対するＲｈの厚みｄＲｈを１０〜６０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を放射光利用の反射率計を用いて調べた結果を表１に示す。Ｒｈ層の厚みが周期長の３０％のとき最大の反射率を示し、その値は６５％であった。また、Ｒｈ層の厚みが周期長の２０％から７０％の範囲で反射率が３０％以上と比較的高い値を示し、Ｒｈ層の厚みが周期長の２０％から４０％の範囲で反射率が５５％以上と極めて高い値を示した。
【００１６】
【表２】
【００１７】
【参考例４】
参考例１と同様にしてスパッタ法により一つの層にＲｕを用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｒｕ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。Ｒｕ層とＢｅ層の一層ずつの厚みを加えた厚み（周期長Ｄ）に対するＲｕの厚みｄＲｕを１０〜９０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を放射光利用の反射率計を用いて調べた結果を表１に示す。Ｒｕ層の厚みが周期長の５０％のとき最大の反射率を示し、その値は６７％であった。また、Ｒｕ層の厚みが周期長の３０％から７０％の範囲で反射率が５０％以上と高い値を示し、Ｒｕ層の厚みが周期長の３０％から６０％の範囲で反射率が５５％以上と極めて高い値を示した。
【００１８】
【表３】
【００１９】
【参考例５】
参考例１と同様にしてスパッタ法により一つの層にＭｏ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、これらを繰り返した多層膜を作製した。Ｍｏ−Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＭｏ−Ｒｈの厚みを１０〜９０％の範囲の中で変化させ、ＭｏとＲｈの組成比を１０〜９０％まで変化させたものをそれぞれ作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｍｏ−Ｒｈ合金においてＲｈの組成比が３０％から７０％の範囲で、ｄＭｏ−Ｒｈ／Ｄが３０〜７０％の範囲の多層膜が直入射角（多層膜の放線からの傾き角）３゜、ピーク波長１１４Å近傍で反射率６０％を越える極めて高い値を示した。特にＭｏ−Ｒｈ合金においてＲｈの組成比が５０％でｄＭｏ−Ｒｈ／Ｄが４５％の場合、上記反射率が７２％という高い値を示した。
【００２０】
【参考例６】
参考例１と同様にしてスパッタ法により一つの層にＭｏ−Ｒｕ合金を用い、他の一つの層にＢｅを使用し、これらの繰り返し多層膜を作製した。Ｍｏ−Ｒｕ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＭｏ−Ｒｕの厚みを１０〜９０％の範囲の中で変化させ、ＭｏとＲｕの組成比を１０〜９０％まで変化させたものをそれぞれ作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｍｏ−Ｒｕ合金においてＲｕの組成比が３０％から７０％の範囲で，ｄＭｏ−Ｒｕ／Ｄが３０〜７０％の範囲の多層膜が直入射角（多層膜の放線からの傾き角）３゜、ピーク波長１１２Å近傍から１１７Å近傍の広い範囲で反射率６０％を越える極めて高い値を示した。特にＭｏ−Ｒｕ合金においてＲｕの組成比が５０％でｄＭｏ−Ｒｕ／Ｄが４０％の場合、上記反射率が７２％という高い値を示した。
【００２１】
【参考例７】
参考例１と同様にしてスパッタ法により一つの層にＲｕ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｒｕ−Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＲｕ−Ｒｈの厚みを１０〜９０％の範囲の中で変化させ、ＲｕとＲｈの組成比を１０〜９０％まで変化させたものをそれぞれ作製した。これら多層膜の波長と反射率との関係を参考例１と同様にして調べたところ、Ｒｕ−Ｒｈ合金においてＲｈの組成比が３０％から７０％の範囲で、ｄＲｕ−Ｒｈ／Ｄが１０〜６０％の範囲の多層膜が、直入射角３゜、ピーク波長１１３Å近傍で反射率６０％を越える極めて高い値を示した。特にＲｕ−Ｒｈ合金においてＲｕの組成比が５０％でｄＭｏ−Ｒｕ／Ｄが２５％の場合、上記反射率が７８％という高い値を示した。
【００２２】
【参考例８】
参考例１と同様にして、一方の層にＭｏを使用し、他の一方の層にＢ−Ｂｅ化合物使用してこれらを繰り返し積層させた多層膜を作製した。Ｍｏ層とＢ−Ｂｅ化合物層のペアの数は６０で周期長６ｎｍとした。Ｂ−Ｂｅ化合物層のＢとＢｅの組成比を２０％〜９０％まで変化させ、周期長Ｄに対するＭｏの厚みｄＭｏを１０〜９０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を参考例１と同様にして調べたところ、ｄＭｏ／Ｄが３０〜７０％の範囲の多層膜が、直入射角３゜、ピーク波長１１５Å近傍で反射率５０％を越える比較的高い値を示した。特にＢｅ化合物としてＢ２ＢｅおよびＢ５Ｂｅを使用した場合、最大反射率は６０％を越えた。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は５〜１８％であり、耐熱性に優れることを示した。特に、Ｂ２ＢｅおよびＢ６Ｂｅを使用した場合、反射率の低下が５〜９％と低く良好な耐熱性を示した。
【００２３】
【参考例９】
参考例１で作製したＭｏ／Ｂｅ多層膜を参考例７と同一の加熱を行った後、加熱前と同一の反射率測定を行ったところ反射率は加熱前の反射率に比べて４５％低下した。
【００２４】
【実施例１】
参考例１と同様にして、一方の層にＭｏ−Ｒｈを使用し、他の一方の層にＢ−Ｂｅ化合物使用してこれらを繰り返し積層させた多層膜を作製した。Ｍｏ−Ｒｈ層とＢ−Ｂｅ化合物層のペアの数は６０で周期長６ｎｍとした。Ｍｏ−Ｒｈ合金においてＲｈの組成比を３０％から７０％の範囲で変化させ、Ｂ−Ｂｅ化合物層のＢとＢｅの組成比を２０％〜９０％の範囲で変化させ、周期長Ｄに対するＭｏ−Ｒｈの厚みｄＭｏ−Ｒｈを３０〜７０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を参考例１と同様にして調べたところ、Ｍｏ−Ｒｈ合金においてＲｈの組成比が３０％から７０％、ｄＭｏ−Ｒｈ／Ｄが４０〜６０％、Ｂ−ＢｅにおけるＢの組成比が３０〜９０％の範囲になる多層膜が、直入射角３゜、ピーク波長１１４Å近傍で反射率５０％を越える比較的高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は５〜２０％であり、Ｍｏ／Ｂｅ多層膜より耐熱性に優れることを示した。
【００２５】
【実施例２】
参考例１と同様にして、一方の層にＭｏ−Ｒｕを使用し、他の一方の層にＢ−Ｂｅ化合物使用してこれらを繰り返し積層させた多層膜を作製した。Ｍｏ−Ｒｕ層とＢ−Ｂｅ化合物層のペアの数は６０で周期長６ｎｍとした。Ｍｏ−Ｒｕ合金においてＲｕの組成比を３０％から７０％の範囲で変化させ、Ｂ−Ｂｅ化合物層のＢとＢｅの組成比を２０％〜９０％の範囲で変化させ、周期長Ｄに対するＭｏ−Ｒｕの厚みｄＭｏ−Ｒｕを３０〜７０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を参考例１と同様にして調べたところ、Ｍｏ−Ｒｕ合金においてＲｕの組成比が３０％から７０％、ｄＭｏ−Ｒｈ／Ｄが４０〜６０％、Ｂ−ＢｅにおけるＢの組成比が３０〜９０％の範囲になる多層膜が、直入射角３゜、ピーク波長１１４Å近傍で反射率５０％を越える比較的高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は５〜２２％であり、Ｍｏ／Ｂｅ多層膜より耐熱性に優れることを示した。
【００２６】
【実施例３】
参考例１と同様にして、一方の層にＲｈ−Ｒｕを使用し、他の一方の層にＢ−Ｂｅ化合物使用してこれらを繰り返し積層させた多層膜を作製した。Ｒｈ−Ｒｕ層とＢ−Ｂｅ化合物層のペアの数は６０で周期長６ｎｍとした。Ｒｈ−Ｒｕ合金においてＲｕの組成比を３０％から７０％の範囲で変化させ、Ｂ−Ｂｅ化合物層のＢとＢｅの組成比を２０％〜９０％の範囲で変化させ、周期長Ｄに対するＲｈ−Ｒｕの厚みｄＲｈ−Ｒｕを１０〜６０％の範囲の中で変化させた。この多層膜の波長と反射率との関係を参考例１と同様にして調べたところ、Ｒｈ−Ｒｕ合金においてＲｕの組成比が３０％から７０％、ｄＲｈ−Ｒｕ／Ｄが２０〜４０％、Ｂ−ＢｅにおけるＢの組成比が３０〜９０％の範囲になる多層膜が、直入射角３゜、ピーク波長１１４Å近傍で反射率６０％を越える比較的高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は５〜２４％であり、Ｍｏ／Ｂｅ多層膜より耐熱性に優れることを示した。
【００２７】
【参考例１０】
参考例１と同様にしてスパッタ法により一つの層としてＣを添加したＲｕ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｃ添加Ｒｕ−Ｒｈ層とＢｅ層のペア数４０で周期長６ｎｍおよびペア数８０で周期長５．６ｎｍとした。周期長に対するＣ添加Ｒｕ−Ｒｈの厚みを２５％とし、ＲｕとＲｈの組成比を５０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｃ添加Ｒｕ−Ｒｈ合金においてＣの組成比が２％から２０％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で周期長６ｎｍの多層膜は反射率５５％を越える高い値を示した。また、周期長５．６ｎｍの多層膜においては波長１０８Åで反射率が５３％が得られた。更に、これら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は４〜１４％であり、耐熱性に優れることを示した。
【００２８】
【参考例１１】
参考例１と同様にしてスパッタ法により一つの層としてＢを添加したＲｕ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｂ添加Ｒｕ−Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＢ添加Ｒｕ−Ｒｈの厚みを２５％とし、ＲｕとＲｈの組成比を５０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｂ添加Ｒｕ−Ｒｈ合金においてＢの組成比が１％から２０％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で反射率５５％を越える高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は７〜２０％であり、Ｍｏ／Ｂｅ多層膜より耐熱性に優れることを示した。
【００２９】
【参考例１２】
参考例１と同様にしてスパッタ法により一つの層としてＯを添加したＲｕ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｏ添加Ｒｕ−Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＯ添加Ｒｕ−Ｒｈの厚みを２５％とし、ＲｕとＲｈの組成比を５０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｏ添加Ｒｕ−Ｒｈ合金においてこのＯの組成比が２％から２０％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で反射率５５％を越える高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は６〜１７％であり、Ｍｏ／Ｂｅ多層膜より耐熱性に優れることを示した。
【００３０】
【参考例１３】
参考例１と同様にしてスパッタ法により一つの層としてＮを添加したＲｕ−Ｒｈ合金を用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｎ添加Ｒｕ−Ｒｈ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＮ添加Ｒｕ−Ｒｈの厚みを２５％とし、ＲｕとＲｈの組成比を５０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｎ添加Ｒｕ−Ｒｈ合金においてＲｕ−Ｒｈに対するＮの組成比が２％から２０％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で反射率５５％を越える高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は６〜１６％であり、耐熱性に優れることを示した。
【００３１】
【参考例１４】
参考例１０と同様にしてスパッタ法により一つの層としてＣを添加したＭｏを用い、他の一つの層にＢｅを使用し、この繰り返し多層膜を作製した。Ｃ添加Ｍｏ層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＣ添加Ｍｏの厚みが４０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｃ添加ＭｏにおいてＭｏに対するＣの組成比が２％から２０％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で反射率５５％を越える高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところ反射率の低下は１〜９％であり、耐熱性に優れることを示した。
【００３２】
【実施例４】
参考例１と同様にしてスパッタ法により一つの層にＲｕ−Ｒｈ合金を用い、他の一つの層にＣａ、Ｃｏ、Ｆｅ、Ｍｏ、Ｎｂ、Ｔｉ、Ｖ、Ｗをそれぞれ１種づつ添加したＢｅを使用し、この繰り返し多層膜を添加物の種類数だけ作製した。Ｒｕ−Ｒｈ合金層とＢｅ層のペアの数は４０で周期長６ｎｍとした。周期長に対するＲｕ−Ｒｈの厚みを２５％とし、ＲｕとＲｈの組成比を５０％の多層膜を作製した。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ、Ｃａ、Ｃｏ、Ｆｅ、Ｍｏ、Ｎｂ、Ｔｉ、Ｖ、Ｗをそれぞれ１種づつ添加したＢｅ層において添加物の組成比が１％から３３％の範囲で、直入射角３゜、ピーク波長１１３Å近傍で反射率５０％を越える高い値を示した。またこれら多層膜を１０^-5Ｔｏｒｒの真空中で４００℃、１時間加熱した後、加熱前と同一の反射率測定を行ったところいずれの多層膜においても反射率の低下は７〜１８％であり、耐熱性に優れることを示した。
【００３３】
【実施例５】
参考例１と同様にして、一方の層にＲｕを使用し、他の一方の層にＢ６Ｂｅを使用してＲｕ層とＢ６Ｂｅ層のペアの数は４０で周期長を３．９ｎｍから７ｎｍまで２Å刻みで多層膜を作製した。層厚比は１：１とした。これら多層膜の波長と反射率反射率との関係を参考例１と同様にして調べたところ直入射角３゜でピーク波長は周期長に対応して７８Å近傍という高反射率化が困難な波長においても２５％というこのような波長領域においては極めて高い反射率を得、更に例えば波長１００Åにおいて３５％、波長１１４Åで反射率５７％、更に、これ以上の波長で１４０Åまで反射率が４５％以上の値を示すなど波長７８Åから１４０Åという長い範囲でこれらの物質の組み合わせの多層膜Ｘ線反射鏡は高い反射率を示した。
【００３４】
【参考例１５】
参考例１と同様、スパッタ法により一つの層にＲｕを用い、他の一つの層にＢを使用し、２層の繰り返し構造の多層膜を作製した。Ｒｕ層とＢ層のペアの数は６０で周期長を５．１ｎｍおよび５．５ｎｍの多層膜を作製した。Ｒｕ層とＢ層の一層ずつの厚みを加えた厚みに対するＲｕの厚みを１０〜９０％の範囲の中で変化させ、この多層膜の波長と反射率との関係を参考例１と同様、軟Ｘ線反射率計を用いて調べた。周期長が５．１ｎｍの場合、軟Ｘ線波長が１００Åに対してはＲｕ層厚が周期長の４５％のとき最大の反射率を示し、その値は５２％であった。また、Ｒｕ層厚が周期長の３０％から６０％の範囲で反射率が３５％以上と比較的高い値を示し、Ｒｕ層厚が周期長の４０％から５０％の範囲で反射率が４５％以上とこの波長では極めて高い値を示した。更に周期長が５．５ｎｍの場合、軟Ｘ線波長が１０８Åに対してはＲｕ層厚が周期長の４５％のとき最大の反射率を示し、その値は５８％であった。また、Ｒｕ層厚が周期長の３０％から６０％の範囲で反射率が４０％以上と比較的高い値を示し、Ｒｕ層厚が周期長の４０％から５０％の範囲で反射率が５０％以上とこの波長では極めて高い値を示した。
【００３５】
【参考例１６】
実施例５と同様、スパッタ法により一つの層にＮを５ａｔ．％添加したＲｕを用い、他の一つの層にＮを５ａｔ．％添加したＢを使用し、２層の繰り返し構造の多層膜を作製した。Ｒｕ−Ｎ層とＢ−Ｎ層のペアの数は６０で周期長を５．１ｎｍおよび５．５ｎｍの多層膜を作製した。Ｒｕ−Ｎ層とＢ−Ｎ層の一層ずつの厚みを加えた厚みに対するＲｕ−Ｎの厚みを１０〜９０％の範囲の中で変化させ、この多層膜の波長と反射率との関係を参考例１と同様、軟Ｘ線反射率計を用いて調べた。周期長が５．１ｎｍの場合、軟Ｘ線波長が１００Åに対してはＲｕ−Ｎ層厚が周期長の４５％のとき実施例５と同様最大の反射率を示し、その値は５１％であった。また、Ｒｕ−Ｎ層厚が周期長の３０％から６０％の範囲で反射率がほぼ３５％以上と比較的高い値を示し、Ｒｕ−Ｎ層厚が周期長の４０％から５０％の範囲で反射率がほぼ４５％以上とこの波長では極めて高い値を示した。更に周期長が５．５ｎｍの場合、軟Ｘ線波長が１０８Åに対してはＲｕ層厚が周期長の４５％のとき最大の反射率を示し、その値は５６％あった。また、Ｒｕ層厚が周期長の３０％から６０％の範囲で反射率がほぼ４０％以上と比較的高い値を示し、Ｒｕ層厚が周期長の４０％から５０％の範囲で反射率がほぼ５０％以上とこの波長では極めて高い値を示した。
【００３６】
【参考例１７】
参考例１と同様にして作製された参考例１から参考例１６、実施例１から実施例５の多層膜を持つ回転放物面、又は回転楕円面、又は球面の形状のＸ線反射鏡、又はこれらを組み合わせたＸ線光学系を第３図のようにクライオターゲットレーザープラズマＸ線点源を囲むようにその近傍数センチメートルのところに配置することによって、点源より放射されるＸ線に対し高い集光効率（立体角にて３ステラジアン程度）と高い反射率（５０％以上）を同時に得ることが出来る。繰り返し数毎秒５００パルス以上、パルスエネルギー１Ｊ以上、パルス時間巾１０^-8秒程度のパルスレーザーを用いれば前記多層膜反射鏡の反射波長巾を持つＸ線に対するプラズマでのＸ線発生効率としては１ステラジアン立体角当たり１％が実験値として検証されているので、平均強度７．５Ｗ以上のスペクトルの揃ったＸ線をａ）平行ビーム、ｂ）集束ビーム、ｃ）集光ビームとして取り出すことができるレーザープラズマＸ線発生装置が構成される。（前記機能を持つ反射鏡の形状は前記形状に限らないことは言うまでもない。）
【００３７】
【発明の効果】
以上述べたように本発明の多層膜は、波長６９．５Åから１２４ Åの範囲で高反射率を示すのに適した光学定数をもつ材料の採用と、構造の選択および界面の平滑化により直入射反射率を向上させることができた。また、反射率が高くなる光学定数を持ちかつ耐熱性に優れた化合物あるいは混合物の採用で多層膜の耐熱性も向上した。このため、従来発明品のＭｏ／Ｂｅ多層膜Ｘ線反射鏡に比べ直入射反射率が高くなるか、耐熱性が向上するか、あるいは両者ともに向上する。反射率が高くなる多層膜を（１）Ｘ線・軟Ｘ線を利用した各種分析に適用した場合、感度や精度が向上し、（２）Ｘ線リソグラフィーに適用した場合、一方の層にＭｏを用いた多層膜よりもスループットの向上がはかれるようになる。
【００３８】
また、耐熱性が向上した多層膜Ｘ線反射鏡を（１）Ｘ線・軟Ｘ線を利用した各種分析に適用した場合、耐熱性が従来の多層膜反射鏡よりも向上するため、使用中での反射率の変化が従来の反射鏡よりも少なくなり、精度や確度が向上する、（２）Ｘ線リソグラフィーに適用した場合は、（１）と同様の理由で適性露光時間を正確に決められるようになる、更に（３）多層膜Ｘ線反射鏡自身の寿命が延びるなどの作用を有することになる。
【００３９】
ここでは波長１１４ Å近傍を中心に材料、構造の例を示したが周期を変えることでほぼブラッグの式に従って反射ピーク波長が変えられることは言うまでもない。また、ＢとＢｅの化合物と金属の組み合わせでＢの吸収端（６９．５Å）近傍からＳｉの吸収端（１２３−１２６ Å）近傍あるいはそれ以上の長い波長領域にわたって高反射率であることをＲｕとＢ_６Ｂｅの組み合わせの実施例で示したが、これは一例であってＲｕ、Ｒｈ、Ｍｏのいずれを用いても、あるいはこれらの合金を用いても、あるいはこれら３種のいずれかに他元素添加物を含んだ物質、あるいはこれら３種の内２種以上を含む合金に他元素の添加物を含んだ物質においても同様の効果があること、また、Ｂ_６Ｂｅの代わりにＢＢｅなどＢとＢｅの化合物、混合物を使用しても同様の効果があることは言うまでもない。
【００４０】
前記多層膜を持つＸ線反射鏡又は複数のＸ線反射鏡から成るＸ線光学系をクライオターゲットレーザープラズマＸ線点源の近傍に配置、組み合わせることにより、スペクトルが揃って且つ強度の大きいＸ線平行ビーム、又は集束ビーム、又は集光ビームを発生させることができるコンパクトで実用的なＸ線発生装置が供される。このようなＸ線発生装置の実現により、Ｘ線縮小投影露光やＸ線ビーム加工機などの応用機器が実用化される。
【図面の簡単な説明】
【図１】多層膜Ｘ線反射鏡の構造を示す図である。
【図２】従来のレーザープラズマＸ線発生装置の構成である。
【図３】レーザープラズマＸ線発生装置の構成である。（ａ）は回転放物面、（ｂ）は回転楕円面、（ｃ）は球面の場合を示す。
【符号の説明】
１基板
２軽元素層
３重元素層
２１パルスレーザ
２２ターゲット
２３放射Ｘ線
２４機械的シャッター又はガス
２５Ｘ線反射鏡
２６デブリス（微粒子・蒸気）
３１パルスレーザ
３２クライオターゲット
３３放射Ｘ線
３４Ｘ線反射鏡
【表１】

（測定条件：直入射角（多層膜の放線からの傾き角）３°、ピーク波長１１４Å近傍）
【表２】

（測定条件：直入射角（多層膜の放線からの傾き角）３°、ピーク波長１１４Å近傍）
【表３】

（測定条件：直入射角（多層膜の放線からの傾き角）３°、ピーク波長１１４Å近傍）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a spectroscopic element for selecting soft X-rays necessary for an apparatus for analyzing light elements with high sensitivity among chemical states, chemical compositions and impurity concentrations of various materials such as semiconductor materials, fine processing, an X-ray microscope, and an X-ray. Necessary for telescopes etc. High efficiency multilayer X-ray reflector It is about.
[0002]
[Prior art]
In various imaging optical systems, the use of shorter wavelength light is being promoted in order to improve the resolution as the wavelength becomes shorter. On the other hand, when the wavelength of light is short, especially when the wavelength is several hundred degrees or less, the reflectance is extremely reduced and the reflectance is almost zero. However, as shown in FIG. 1, for example, when two types of material layers are alternately and regularly laminated with a constant thickness, a direct reflection mirror (multilayer film reflection mirror) having a high reflectance utilizing Bragg diffraction is realized.
[0003]
In particular, for soft X-rays having a wavelength of about 130 nm, a Mo / Si multilayer film in which several tens or more layers of Mo layers and Si layers are regularly and alternately laminated several nm at a time provides a direct incidence reflectance of as much as 60% or more. Therefore, it has come to be widely used as a reflection mirror such as an X-ray reduction exposure, an X-ray microscope, and an astronomical telescope. As the X-ray source, synchrotron radiation (SR), laser plasma X-ray (LPX), and gas pinch plasma (GPP) are used, but the synchrotron radiation requires a large-scale and expensive apparatus using an accelerator. Required, and the gas pinch plasma is a light source with a few orders of magnitude lower ¹² W / cm ² A large and relatively compact laser plasma X-ray is promising as a practical light source for the above application. However, as shown in FIG. 2, in a laser plasma X-ray source excited by a pulsed laser beam, vapor and fine particles of a target material evaporate, so that this adheres to an X-ray optical system represented by an X-ray reflector. If its performance is impaired. To prevent this, X-rays generated by inserting a shutter that is mechanically synchronized with the reflector, inserting buffer gas, or placing the reflector far away are collected. Available for use. However, in any case, the reflecting mirror has to be arranged at a place distant from the laser plasma X-ray source which is a point source, so that there is a drawback that the use efficiency of X-rays is low, and its practical use is hindered. Was. On the other hand, in order to further improve the resolution in these applications, it was necessary to use soft X-rays having a wavelength shorter than about 130 °. However, when the Mo / Si multilayer film is used at a wavelength of 124 ° or less (below the L absorption edge of Si), the direct incident reflectance is extremely reduced to several to several tens of percent, and cannot be used practically. Therefore, a multilayer X-ray reflecting mirror having a combination of Mo and B4C has been applied, but even with this, only a reflectivity of about 30% was obtained, which was not suitable for practical use. Recently, a multilayer X-ray reflecting mirror in which Mo and Be layers are alternately laminated has been manufactured. With this multilayer X-ray reflecting mirror, the direct incident reflection exceeding 60% at the wavelength immediately above the absorption edge of Be (directly above 111 °). It has been found that a high reflectivity can be obtained, and in the above-mentioned applications and the like, it is expected that the resolution can be improved by obtaining a high reflectance even with soft X-rays having a short wavelength. Recently, a chemically inert rare gas element is liquefied or solidified at a low temperature, or a low temperature gas state having a vapor density close to that of a liquid, and is used as a target material of a laser plasma X-ray source (LPX). It can be said that the LPX has begun to be put into practical use by inventing a cryotarget in which the target particles are not attached to the reflecting mirror and other X-ray photon systems (Japanese Patent No. 2614457).
[0004]
[Problems to be solved by the invention]
In general, an X-ray imaging optical system uses a plurality of multilayer film reflecting mirrors as shown in FIG. 1, so that generally the X-ray focusing and transmittance are greatly reduced in the entire optical system. For this reason, a slightly higher reflectance is required for each reflector.
[0005]
In the case of a combination of Mo and Be, when the film is actually formed, Mo and Be are aggregated, so that the roughness of the interface of each layer becomes large. There was a problem of lowering. Further, in the Mo / Be combination, the melting point of Be is as low as about 1270 ° C., and therefore, as in the case of the Mo / Si multilayer X-ray reflecting mirror, the reflectance is increased due to the use of high-intensity soft X-rays and the high temperature of the use environment. There is also a problem of heat resistance that the temperature drops rapidly and cannot be used stably. In addition, the multilayer X-ray mirror having a combination of Mo and Be has a problem in that the reflectance is extremely reduced when the wavelength is 111 ° or less, so that it cannot be used below this wavelength. On the other hand, one of the present inventors, Mochizuki, found that the Xe (xenon) cryotarget laser plasma X-ray source, which is a typical example of a cryotarget, has the highest emission spectrum intensity at a wavelength of around 108 °. ^* There is currently no reflector that provides sufficient reflectivity (50% or more) at these wavelengths. It is also powerful to take advantage of the greatest advantage of using a cryogenic target, that is, the ability to place a reflector near the source to avoid the attachment of target particles and to form a condensed photon system with a large condensing solid angle. There is a need for a long-life reflector that maintains a high reflectance stably even when exposed to scattered laser light from X-rays or plasma, but no conventional reflector satisfies these requirements. ( ^* References T. Mochizuki et al. , Appl. Phys. Lett. (1998) Jan. to be published)
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides (1) using a layer containing one kind of Ru and Rh as a material of one layer, and using Be and B6Be as another material, and (2) using one layer. A layer containing one kind of Ru and Rh was used as a material for the above, and a compound of Be and a metal was used for the other one. (3) A layer containing a compound of Ru or Rh and a metal was used as a material for one of the layers. And using a layer containing one of B, Be, and a Be compound on the other side. High-efficiency, long-life multilayer X-ray reflector It is the gist.
[0007]
[Action]
According to this means, in order to improve the reflectivity, a multilayer film using Rh instead of Mo was produced in the Mo / Be multilayer film, and the reflectivity was measured at a wavelength of 115 °. The end result was that the reflectivity was improved by 4%. Emit. This indicates that there is a possibility that there is a material whose optical constant is more suitable than Mo. Therefore, when Ru, which is a material having an optical constant more suitable at this wavelength than Mo, and furthermore, an alloy of Mo and Ru or Rh, or an alloy of Ru and Rh is used instead of Mo, the X-ray reflectivity increases.
[0008]
In addition, the reflectivity greatly depends on the optical constant, but when the roughness of the layer interface of the multilayer film becomes large, the obtained reflectivity becomes lower than the calculated value. On the other hand, alloys and metals to which elements such as B 1, C 2, O 2, and N are added are usually easily formed into amorphous layers when they are formed as ultra-thin layers having a thickness of several nm to several tens nm. The layer interface becomes smoother than a single layer. Therefore, when an alloy to which these elements are added is used instead of Mo, the effect of improving the reflectance appears. Therefore, when a multilayer film using such a substance in one layer and using Be in the other layer is applied to (1) various analyzes using X-rays and soft X-rays, the multilayer film Is higher than a multilayer film using a Mo layer as a layer other than the Be layer, so that sensitivity and accuracy are improved. (2) When applied to X-ray lithography, Mo is used in a layer other than the Be layer. The throughput can be improved more than the multi-layered film for the same reason as (1).
[0009]
Further, a substance obtained by adding or combining other elements such as B, C, O, and N to a metal, including Be, generally has a higher melting point than a simple metal, and also suppresses diffusion between layers. Therefore, when these substances are used as constituent materials of the multilayer film, the heat resistance is improved. Therefore, when a multilayer film using these substances is applied to (1) various analyzes using X-rays and soft X-rays, Is improved over conventional multilayer mirrors, so changes in reflectivity during use are smaller than conventional mirrors, and accuracy and accuracy are improved. (2) When applied to X-ray lithography, For the same reason as (1), the appropriate exposure time can be accurately determined, and (3) the life of the multilayer film itself is extended.
[0010]
Further, since the reflecting mirror of the present invention can obtain a sufficiently high reflectance (50%) even at around 108 °, a highly efficient and long-lasting condensing optics particularly for a laser plasma X-ray source using a cryogenic target. It has the effect of realizing a system. In particular, there is an effect that the throughput of reduction projection lithography is improved to a practical level. There is also an effect of increasing the speed of X-ray processing.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described along with examples.
[0012]
[ Reference Example 1 ]
Using a RF magnetron sputtering apparatus equipped with a plurality of material targets, ^-8 After exhausting to the Torr stage, Ar gas was introduced into the film formation chamber to make the film formation chamber 3 × 10 ^-3 After the atmosphere was changed to an Ar atmosphere at a pressure of Torr, a discharge was generated to produce a multilayer film in which a Mo layer and a Be layer were repeatedly laminated. The number of pairs of the Mo layer and the Be layer was 40 and the cycle length was 6 nm. The thickness dMo of Mo with respect to the thickness (period length D) obtained by adding the thickness of each of the Mo layer and the Be layer was changed within a range of 10 to 90%. Table 1 shows the results of the measurement of the relationship between the wavelength and the reflectance of this multilayer film using a reflectometer utilizing radiation light. When the thickness of the Mo layer was 50% of the period length, the reflectance was the maximum, and the value was 62%. In addition, the reflectivity showed a high value of 40% or more when the thickness of the Mo layer was in the range of 20% to 70% of the cycle length.
[0013]
[Table 1]
[0014]
[ Reference Example 2 ]
Reference Example 1 N at 5 at. % Added Mo-N layer and N at 5 at. % Was added to produce a multilayer film in which Be-N layers were repeatedly laminated. A Mo-N layer and a Be-N layer having 40 pairs and a period length of 6 nm and a pair having 80 periods and a period length of 5.6 nm were produced. The thickness dMo-N of Mo with respect to the thickness D, which is the sum of the thicknesses of the Mo-N layer and the Be-N layer, was changed within a range of 10 to 90%. Reference Example 1 When the relationship between the wavelength and the reflectance of this multilayer film was measured using a reflectometer, the thickness of the Mo-N layer was 50% of the periodic length with respect to soft X-rays having a wavelength of 114 °. Shows a reflectance of 69%, and Reference Example 1 Similarly, the reflectance was as high as 45% or more when the thickness of the Mo-N layer was in the range of 20% to 70% of the period length. Further, the one having a period length of 6 nm shows a reflectance of about 51% with respect to soft X-rays having a wavelength of 108 ° when the thickness of the Mo—N layer is 55% of the period length, and Reference Example 1 Similarly to the above, when the thickness of the Mo-N layer is in the range of 45% to 70% of the period length, the reflectivity shows an unprecedented high value for wavelengths of 45% or more and 110 ° or less.
[0015]
[ Reference Example 3 ]
Reference Example 1 Similarly to above, Rh was used for one layer and Be was used for another layer by a sputtering method, and a multilayer film in which these layer configurations were repeated was produced. The number of pairs of the Rh layer and the Be layer was 40 and the cycle length was 6 nm. The thickness dRh of Rh with respect to the thickness (period length D) obtained by adding the thickness of each of the Rh layer and the Be layer was changed in the range of 10 to 60%. Table 1 shows the results of examining the relationship between the wavelength and the reflectance of this multilayer film using a reflectometer utilizing synchrotron radiation. When the thickness of the Rh layer was 30% of the period length, the maximum reflectance was exhibited, and the value was 65%. Further, when the thickness of the Rh layer is in the range of 20% to 70% of the period length, the reflectivity shows a relatively high value of 30% or more, and when the thickness of the Rh layer is in the range of 20% to 40% of the period length, the reflectivity is high. Showed an extremely high value of 55% or more.
[0016]
[Table 2]
[0017]
[ Reference example 4 ]
Reference Example 1 In the same manner as described above, Ru was used for one layer and Be was used for another layer by a sputtering method, thereby repeatedly producing a multilayer film. The number of pairs of the Ru layer and the Be layer was 40 and the cycle length was 6 nm. The thickness dRu of Ru with respect to the thickness (period length D) obtained by adding the thickness of each of the Ru layer and the Be layer was changed within a range of 10 to 90%. Table 1 shows the result of examining the relationship between the wavelength and the reflectance of the multilayer film using a reflectometer utilizing synchrotron radiation. The maximum reflectance was exhibited when the thickness of the Ru layer was 50% of the period length, and the value was 67%. Further, the reflectivity shows a high value of 50% or more when the thickness of the Ru layer is in the range of 30% to 70% of the period length, and the reflectivity is 55% when the thickness of the Ru layer is in the range of 30% to 60% of the period length. %, Which is an extremely high value.
[0018]
[Table 3]
[0019]
[ Reference example 5 ]
Reference Example 1 A Mo-Rh alloy was used for one layer and Be was used for the other layer by sputtering in the same manner as described above, and a multilayer film was formed by repeating these. The number of pairs of the Mo-Rh layer and the Be layer was 40 and the cycle length was 6 nm. Thicknesses of Mo-Rh with respect to the cycle length were changed within a range of 10 to 90%, and those in which the composition ratio of Mo and Rh was changed to 10 to 90% were produced. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of Rh in the Mo-Rh alloy was in the range of 30% to 70%, and the dMo-Rh / D was in the range of 30 to 70%, the multilayer film was found to have a normal incidence angle (of the multilayer film). It showed an extremely high value exceeding 60% in the vicinity of a peak angle of 3 4 ° and a peak wavelength of 114 °. In particular, when the composition ratio of Rh was 50% and dMo-Rh / D was 45% in the Mo-Rh alloy, the reflectance was as high as 72%.
[0020]
[ Reference Example 6 ]
Reference Example 1 In the same manner as described above, a Mo-Ru alloy was used for one layer by a sputtering method, and Be was used for another layer, thereby producing a repetitive multilayer film. The number of pairs of the Mo-Ru layer and the Be layer was 40 and the cycle length was 6 nm. Thicknesses of Mo-Ru with respect to the cycle length were changed within a range of 10 to 90%, and those in which the composition ratio of Mo and Ru was changed to 10 to 90% were produced. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of Ru in the Mo—Ru alloy was in the range of 30% to 70% and the dMo—Ru / D was in the range of 30% to 70%, the multilayer film was found to have a normal incidence angle (of the multilayer film). An extremely high value exceeding 60% was exhibited in a wide range from an inclination angle of 3 °) to 3 ° and a peak wavelength from 112 ° to 117 °. In particular, when the composition ratio of Ru was 50% and dMo-Ru / D was 40% in the Mo-Ru alloy, the reflectance was as high as 72%.
[0021]
[ Reference Example 7 ]
Reference Example 1 In the same manner as described above, a Ru-Rh alloy was used for one layer and Be was used for another layer by sputtering, and a repetitive multilayer film was produced. The number of Ru-Rh layer and Be layer pairs was 40 and the cycle length was 6 nm. Thicknesses of Ru-Rh with respect to the cycle length were changed within a range of 10 to 90%, and those in which the composition ratio of Ru and Rh was changed to 10 to 90% were produced. The relationship between the wavelength and the reflectance of these multilayer films is Reference Example 1 When the composition ratio of Rh in the Ru—Rh alloy was in the range of 30% to 70% and dRu−Rh / D was in the range of 10% to 60%, the direct incidence angle was 3 °, At a peak wavelength near 113 °, the reflectance was extremely high, exceeding 60%. In particular, when the Ru-Rh alloy had a Ru composition ratio of 50% and dMo-Ru / D of 25%, the reflectivity showed a high value of 78%.
[0022]
[ Reference Example 8 ]
Reference Example 1 In the same manner as described above, a multilayer film in which Mo was used for one layer and a B-Be compound was used for the other layer, and these were repeatedly laminated, was produced. The number of pairs of the Mo layer and the B-Be compound layer was 60, and the cycle length was 6 nm. The composition ratio of B and Be in the B-Be compound layer was changed from 20% to 90%, and the thickness dMo of Mo with respect to the period length D was changed in the range of 10 to 90%. The relationship between the wavelength and the reflectance of this multilayer film Reference Example 1 As a result, the multilayer film having a dMo / D in the range of 30 to 70% showed a relatively high value exceeding 50% in the vicinity of a normal incidence angle of 3 ° and a peak wavelength of 115 °. In particular, when B2Be and B5Be were used as Be compounds, the maximum reflectance exceeded 60%. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 5 to 18%, indicating excellent heat resistance. In particular, when B2Be and B6Be were used, the decrease in reflectance was as low as 5 to 9%, indicating good heat resistance.
[0023]
[ Reference Example 9 ]
Reference Example 1 Mo / Be multilayer film prepared in Reference Example 7 After performing the same heating as above, the same reflectance measurement as before heating was performed. As a result, the reflectance was reduced by 45% as compared with the reflectance before heating.
[0024]
[ Example 1 ]
Reference Example 1 In the same manner as in the above, a multilayer film in which Mo-Rh was used for one layer and a B-Be compound was used for the other layer, and these were repeatedly laminated, was produced. The number of pairs of the Mo-Rh layer and the B-Be compound layer was 60 and the cycle length was 6 nm. In the Mo—Rh alloy, the composition ratio of Rh is changed in the range of 30% to 70%, the composition ratio of B and Be in the B—Be compound layer is changed in the range of 20% to 90%, and Mo with respect to the period length D is changed. -Rh thickness dMo-Rh was varied in the range of 30-70%. The relationship between the wavelength and the reflectance of this multilayer film Reference Example 1 When the composition ratio of Rh in the Mo-Rh alloy was in the range of 30% to 70%, dMo-Rh / D was in the range of 40 to 60%, and the composition ratio of B in B-Be was in the range of 30 to 90%. Has a relatively high value exceeding 50% in the vicinity of a normal incidence angle of 3 ° and a peak wavelength of 114 °. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 5 to 20%, indicating that the heat resistance was superior to that of the Mo / Be multilayer film. Indicated.
[0025]
[ Example 2 ]
Reference Example 1 In the same manner as described above, a multilayer film in which Mo-Ru was used for one layer and a B-Be compound was used for the other layer, and these were repeatedly laminated, was produced. The number of pairs of the Mo-Ru layer and the B-Be compound layer was 60 and the cycle length was 6 nm. In the Mo—Ru alloy, the composition ratio of Ru is changed in a range of 30% to 70%, and the composition ratio of B and Be in the B—Be compound layer is changed in a range of 20% to 90%. -Ru thickness dMo-Ru was varied in the range of 30-70%. The relationship between the wavelength and the reflectance of this multilayer film Reference Example 1 When the composition ratio of Ru in the Mo-Ru alloy was in the range of 30% to 70%, dMo-Rh / D was in the range of 40 to 60%, and the composition ratio of B in B-Be was in the range of 30 to 90%. Has a relatively high value exceeding 50% in the vicinity of a normal incidence angle of 3 ° and a peak wavelength of 114 °. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 5 to 22%, indicating that the heat resistance was superior to that of the Mo / Be multilayer film. Indicated.
[0026]
[ Example 3 ]
Reference Example 1 In the same manner as described above, a multilayer film in which Rh-Ru was used for one layer and a B-Be compound was used for the other layer, and these were repeatedly laminated, was produced. The number of pairs of the Rh-Ru layer and the B-Be compound layer was 60, and the cycle length was 6 nm. In the Rh-Ru alloy, the composition ratio of Ru is changed in the range of 30% to 70%, the composition ratio of B and Be in the B-Be compound layer is changed in the range of 20% to 90%, and Rh with respect to the period length D is changed. -Ru thickness dRh-Ru was changed in the range of 10 to 60%. The relationship between the wavelength and the reflectance of this multilayer film Reference Example 1 When the composition ratio of Ru in the Rh-Ru alloy was 30% to 70%, dRh-Ru / D was 20 to 40%, and the composition ratio of B in B-Be was 30 to 90%. Has a relatively high value exceeding 60% in the vicinity of a normal incident angle of 3 ° and a peak wavelength of 114 °. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed, and the decrease in reflectance was 5 to 24%, indicating that the heat resistance was superior to that of the Mo / Be multilayer film. Indicated.
[0027]
[ Reference example 10 ]
Reference Example 1 In the same manner as described above, a Ru-Rh alloy to which C was added was used as one layer by sputtering, and Be was used as another layer, thereby repeatedly forming a multilayer film. The period length was 6 nm when the number of pairs of the C-doped Ru-Rh layer and Be layer was 40, and the period length was 5.6 nm when the number of pairs was 80. The thickness of the C-added Ru-Rh with respect to the period length was 25%, and a multilayer film having a composition ratio of Ru and Rh of 50% was produced. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of C in the C-added Ru—Rh alloy was in the range of 2% to 20%, the multilayer film having a direct incidence angle of 3 ° and a peak length of 113 ° and a period length of 6 nm showed a reflectance of 55%. %. In the multilayer film having a period length of 5.6 nm, a reflectance of 53% was obtained at a wavelength of 108 °. Furthermore, these multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed, and the decrease in reflectance was 4 to 14%, indicating excellent heat resistance.
[0028]
[ Reference Example 11 ]
Reference Example 1 In the same manner as in the above, a Ru-Rh alloy to which B was added was used as one layer by sputtering, and Be was used as another layer, thereby repeatedly producing a multilayer film. The number of pairs of the B-doped Ru-Rh layer and the Be layer was 40, and the cycle length was 6 nm. A multilayer film having a thickness of B-added Ru-Rh with respect to the cycle length of 25% and a composition ratio of Ru and Rh of 50% was prepared. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of B in the B-added Ru-Rh alloy was in the range of 1% to 20%, the B-added Ru-Rh alloy showed a high value exceeding 55% in the vicinity of a normal incidence angle of 3 ° and a peak wavelength of 113 °. Was. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 7 to 20%, indicating that the heat resistance was superior to that of the Mo / Be multilayer film. Indicated.
[0029]
[ Reference Example 12 ]
Reference Example 1 In the same manner as in the above, a Ru-Rh alloy to which O was added was used as one layer by sputtering, and Be was used as another layer, thereby repeatedly producing a multilayer film. The number of pairs of the O-added Ru-Rh layer and the Be layer was 40, and the cycle length was 6 nm. A multilayer film was prepared in which the thickness of O-added Ru-Rh with respect to the period length was 25% and the composition ratio of Ru and Rh was 50%. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of O in the O-added Ru-Rh alloy is in the range of 2% to 20%, the O-added Ru-Rh alloy has a high value exceeding 55% at a normal incidence angle of 3 ° and a peak wavelength of 113 °. Indicated. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 6 to 17%, indicating that the heat resistance was superior to that of the Mo / Be multilayer film. Indicated.
[0030]
[ Reference Example 13 ]
Reference Example 1 In the same manner as in the above, a Ru-Rh alloy to which N was added was used as one layer by a sputtering method, and Be was used as another layer, thereby repeatedly producing a multilayer film. The number of pairs of the N-doped Ru-Rh layer and the Be layer was 40, and the cycle length was 6 nm. A multilayer film having a thickness of N-added Ru-Rh with respect to the cycle length of 25% and a composition ratio of Ru and Rh of 50% was produced. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of N to Ru-Rh in the N-added Ru-Rh alloy is in the range of 2% to 20%, the reflectance exceeds 55% at a normal incident angle of 3 ° and a peak wavelength of 113 °. It showed a high value. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed. The decrease in reflectance was 6 to 16%, indicating excellent heat resistance.
[0031]
[ Reference Example 14 ]
Reference example 10 In the same manner as described above, Mo was added to C as one layer by a sputtering method, and Be was used for another layer, thereby repeatedly producing a multilayer film. The number of pairs of the C-doped Mo layer and the Be layer was 40, and the cycle length was 6 nm. A multilayer film was formed in which the thickness of C-doped Mo with respect to the cycle length was 40%. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 When the composition ratio of C to Mo in the C-added Mo was in the range of 2% to 20%, a high value exceeding 55% at a normal incidence angle of 3 ° and a peak wavelength of 113 ° was obtained. . These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed, and the decrease in reflectance was 1 to 9%, indicating excellent heat resistance.
[0032]
[ Example 4 ]
Reference Example 1 Using a Ru-Rh alloy for one layer by sputtering in the same manner as in above, and using Be, to which Ca, Co, Fe, Mo, Nb, Ti, V, and W are added, one by one, for another layer. This repeated multilayer film was prepared by the number of kinds of additives. The number of pairs of the Ru—Rh alloy layer and the Be layer was 40, and the cycle length was 6 nm. A multilayer film was prepared in which the thickness of Ru-Rh with respect to the cycle length was 25% and the composition ratio of Ru and Rh was 50%. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 In the Be layer to which Ca, Co, Fe, Mo, Nb, Ti, V, and W were added one by one, when the composition ratio of the additive was in the range of 1% to 33%, direct incidence was performed. It showed a high value exceeding 50% in reflectance near the angle of 3 ° and the peak wavelength of 113 °. These multilayer films are ^-Five After heating at 400 ° C. for 1 hour in a vacuum of Torr, the same reflectance measurement as before heating was performed, and the reduction in reflectance was 7 to 18% in any of the multilayer films. Indicated.
[0033]
[ Example 5 ]
Reference Example 1 In the same manner as above, Ru is used for one layer and B6Be is used for the other layer. The number of pairs of the Ru layer and the B6Be layer is 40, and the periodic length is multiplied by 2 ° from 3.9 nm to 7 nm. A film was prepared. The layer thickness ratio was 1: 1. The relationship between the wavelength and the reflectance of these multilayer films is described. Reference Example 1 In the same manner as in the above, it was found that at a direct incidence angle of 3 °, the peak wavelength was around 78 ° corresponding to the period length, and even at a wavelength where it was difficult to achieve high reflectance, an extremely high reflectance was obtained in such a wavelength region of 25%. For example, 35% at a wavelength of 100 °, 57% of a reflectance at a wavelength of 114 °, and a reflectance of 45% or more at a further wavelength from 140 ° to a wavelength of 78 ° to 140 °. The combined multilayer X-ray reflector showed high reflectivity.
[0034]
[ Reference Example 15 ]
Reference Example 1 Similarly to the above, a multilayer film having a two-layer repeating structure was manufactured by using Ru for one layer and B for another layer by a sputtering method. The number of pairs of the Ru layer and the B layer was 60, and multilayer films having a period length of 5.1 nm and 5.5 nm were produced. The thickness of Ru with respect to the thickness obtained by adding the thickness of each of the Ru layer and the B layer is changed within a range of 10 to 90%, and the relationship between the wavelength and the reflectance of the multilayer film is changed. Reference Example 1 In the same manner as in the above, the examination was performed using a soft X-ray reflectometer. When the period length was 5.1 nm, the maximum reflectance was exhibited when the thickness of the Ru layer was 45% of the period length with respect to the soft X-ray wavelength of 100 °, and the value was 52%. Further, when the Ru layer thickness is in the range of 30% to 60% of the cycle length, the reflectivity shows a relatively high value of 35% or more, and when the Ru layer thickness is in the range of 40% to 50% of the cycle length, the reflectivity is 45%. % Or more, an extremely high value was shown at this wavelength. Further, when the period length was 5.5 nm, the maximum reflectivity was exhibited when the thickness of the Ru layer was 45% of the period length for a soft X-ray wavelength of 108 °, and the value was 58%. Further, the reflectivity shows a relatively high value of 40% or more when the Ru layer thickness is in the range of 30% to 60% of the cycle length, and the reflectivity is 50% when the Ru layer thickness is in the range of 40% to 50% of the cycle length. % Or more, an extremely high value was shown at this wavelength.
[0035]
[ Reference Example 16 ]
Example 5 In the same manner as described above, 5 at. % Of Ru and 5 at.% Of N in another layer. Using B to which% was added, a multilayer film having a two-layer repeating structure was prepared. The number of pairs of Ru-N layers and BN layers was 60, and multilayer films having a period length of 5.1 nm and 5.5 nm were produced. The thickness of Ru-N with respect to the sum of the thicknesses of the Ru-N layer and the BN layer is changed within the range of 10 to 90%, and the relationship between the wavelength and the reflectance of this multilayer film is changed. Reference Example 1 In the same manner as in the above, the examination was performed using a soft X-ray reflectometer. When the period length is 5.1 nm, when the soft X-ray wavelength is 100 °, the Ru-N layer thickness is 45% of the period length Example 5 The maximum reflectance was shown in the same manner as the above, and the value was 51%. The reflectivity shows a relatively high value of approximately 35% or more when the Ru-N layer thickness is in the range of 30% to 60% of the period length, and the Ru-N layer thickness is in the range of 40% to 50% of the period length. , The reflectance was extremely high at this wavelength of approximately 45% or more. Further, when the period length was 5.5 nm, the maximum reflectance was exhibited when the thickness of the Ru layer was 45% of the period length, and the value was 56% for the soft X-ray wavelength of 108 °. The reflectivity shows a relatively high value of approximately 40% or more when the Ru layer thickness is in the range of 30% to 60% of the cycle length, and the reflectance is high when the Ru layer thickness is in the range of 40% to 50% of the cycle length. At this wavelength, an extremely high value of approximately 50% or more was shown.
[0036]
[ Reference Example 17 ]
Reference Example 1 Produced in the same way as Reference Examples 1 to 16 and Examples 1 to 5 An X-ray reflecting mirror having a paraboloid of revolution, a spheroidal surface, or a spherical shape having a multilayer film, or an X-ray optical system obtained by combining these is used as a cryo-target laser plasma X-ray point source as shown in FIG. By arranging it several centimeters in the vicinity so as to surround it, it simultaneously achieves high light-collecting efficiency (about 3 steradians in solid angle) and high reflectivity (more than 50%) for X-rays emitted from a point source. Can be obtained. Repetition rate 500 pulses or more per second, pulse energy 1 J or more, pulse duration 10 ^-8 If a pulse laser of about seconds is used, the X-ray generation efficiency of plasma with respect to X-rays having a reflection wavelength width of the multilayer mirror is verified as an experimental value of 1% per 1 steradian solid angle. A laser plasma X-ray generator capable of extracting X-rays having a uniform spectrum of 7.5 W or more as a) a parallel beam, b) a focused beam, and c) a focused beam is configured. (It goes without saying that the shape of the reflecting mirror having the above function is not limited to the above shape.)
[0037]
【The invention's effect】
As described above, the multilayered film of the present invention employs a material having an optical constant suitable for exhibiting a high reflectance in the wavelength range of 69.5 ° to 124 °, and has a direct structure by selecting a structure and smoothing the interface. The incident reflectance was able to be improved. Further, the use of a compound or a mixture having an optical constant that increases the reflectance and excellent heat resistance also improved the heat resistance of the multilayer film. For this reason, the direct-incidence reflectance, the heat resistance, or both are improved as compared with the Mo / Be multilayer X-ray reflecting mirror of the conventional invention. When a multilayer film having a high reflectance is applied to (1) various analyses using X-rays and soft X-rays, sensitivity and accuracy are improved. (2) When applied to X-ray lithography, Mo is applied to one layer. Throughput can be improved as compared with a multilayer film using.
[0038]
In addition, when a multilayer X-ray mirror with improved heat resistance is applied to (1) various analyses using X-rays and soft X-rays, the heat resistance is higher than that of conventional multilayer film mirrors. (2) When applied to X-ray lithography, the appropriate exposure time is determined accurately for the same reason as (1), because the change in the reflectance at the time is smaller than that of the conventional reflector, and the accuracy and accuracy are improved. And (3) extending the life of the multilayer X-ray reflecting mirror itself.
[0039]
Here, an example of the material and the structure is shown around the wavelength of about 114 °, but it goes without saying that the reflection peak wavelength can be changed substantially according to the Bragg equation by changing the period. In addition, it is Ru that the combination of a compound of B and Be and a metal has a high reflectance over a long wavelength range from near the absorption edge of B 2 (69.5 °) to near the absorption edge of Si (123-126 °) or longer. And B ₆ The examples of the combination of Be are shown in the examples, but this is merely an example, and any of Ru, Rh, and Mo, an alloy thereof, or an additive of another element may be added to any of these three types. And the alloy containing two or more of these three elements has the same effect. ₆ It goes without saying that the same effect can be obtained by using a compound or a mixture of B and Be such as BBe instead of Be.
[0040]
By arranging and combining an X-ray reflecting mirror having the multilayer film or an X-ray optical system comprising a plurality of X-ray reflecting mirrors near a cryogenic laser plasma X-ray point source, X-rays having a uniform spectrum and high intensity A compact and practical X-ray generator capable of generating a collimated, focused or focused beam is provided. By realizing such an X-ray generator, applied devices such as X-ray reduction projection exposure and X-ray beam processing machines are put into practical use.
[Brief description of the drawings]
FIG. 1 is a diagram showing a structure of a multilayer X-ray reflecting mirror.
FIG. 2 is a configuration of a conventional laser plasma X-ray generator.
FIG. 3 is a configuration of a laser plasma X-ray generator. (A) shows the case of a paraboloid of revolution, (b) shows the case of a spheroid, and (c) shows the case of a spherical surface.
[Explanation of symbols]
1 substrate
2 Light element layer
3 Heavy element layer
21 pulse laser
22 Target
23 X-ray radiation
24 Mechanical shutter or gas
25 X-ray reflector
26 debris (fine particles / steam)
31 pulse laser
32 cryo targets
33 X-ray radiation
34 X-ray reflector
[Table 1]

(Measurement conditions: direct incident angle (angle of inclination of multilayer film from radiation) 3 °, peak wavelength around 114 °)
[Table 2]

(Measurement conditions: direct incident angle (angle of inclination of multilayer film from radiation) 3 °, peak wavelength around 114 °)
[Table 3]

(Measurement conditions: direct incident angle (angle of inclination of multilayer film from radiation) 3 °, peak wavelength around 114 °)

Claims

A layer containing at least one of Rh and Ru as a constituent material of a multilayer X-ray reflector in which two or more layers covering a soft X-ray wavelength range of 69.5 ° to 124 ° are laminated a plurality of times, and BBe, B6Be A multilayer X-ray reflector comprising a layer containing at least one of the following.

A layer containing at least one of Rh and Ru as a constituent material of a multilayer X-ray reflecting mirror in which two or more layers covering a soft X-ray wavelength range of 69.5 ° to 124 ° are laminated a plurality of times; A multilayer X-ray reflector, characterized by using a layer containing at least one of the above compounds.

3. The multilayer X-ray mirror according to claim 2, wherein the Be compound contains at least one of Ca, Co, Fe, Mo, Nb, Ti, V, and W.

4. The method according to claim 1, wherein the layer containing at least one of Rh and Ru is an alloy layer of Rh and Ru, wherein the composition ratio of Rh is in the range of 30% to 70%, and the thickness of the alloy layer is 10% of the period of the repeating layer. A multilayer X-ray reflecting mirror, characterized by being in the range of -60%.

Layers containing at least one of Rh and Ru in a constituent material of a multilayer X-ray reflector in which two or more layers covering a soft X-ray wavelength range of 69.5 ° to 124 ° are laminated a plurality of times, and B and Be , A multilayer film X-ray mirror using a layer containing at least one kind of Be compound, wherein at least the layer containing one kind of Rh and Ru is an alloy layer of Mo and Rh, or an alloy layer of Mo and Ru, and each of them is Rh or Mo for Mo. A multilayer X-ray mirror characterized in that the composition ratio of Ru is in the range of 30% to 70%, and the thickness of the alloy layer is in the range of 30 to 70% of the cycle of the repeating layer .