JP3931963B2 - Solution raw material for metal organic chemical vapor deposition containing β-diketonate complex of copper (II) and method for producing copper thin film using the same - Google Patents

Description

（式中、Ｒはイソプロピル基又は第三ブチル基を表し、Ｒ¹はメチル基又はエチル基を表し、Ｒ²はプロピル基又はブチル基を表す。）
この銅原料は室温で液体であり、分子内にハロゲン元素や窒素元素等の薄膜製造時に影響を及ぼすと考えられる元素を含んでいないため、各種ＣＶＤ法に適し、更に、既存の固体である銅(II)錯体からなるＣＶＤ用銅原料と同等の熱的、化学的安定性を有する。
【０００７】
【発明が解決しようとする課題】
しかし特開２００１−１８１８４０号公報の上記式（２）で示される銅原料は常温で液体であるが、その粘性は非常に高く、この銅原料をＭＯＣＶＤ装置に供給するには高圧で供給しなければならないため、成膜性に問題が残る。またこの銅原料を溶液に溶解して溶液原料としてＭＯＣＶＤ装置に供給しても、この銅原料の分解温度は約４５０℃であり、従来より一般的に用いられている有機銅化合物の分解温度に比べて非常に高いため、成膜し難い問題もあった。またこの上記式（２）で示される銅原料は分子構造が偏ったバランスの悪い構造を有しているため、十分な成膜安定性が得られなかった。
【０００８】
本発明の目的は、熱安定性に優れ、保存状態で分解しにくく寿命が長い銅(II)のβ-ジケトネート錯体を含む有機金属化学蒸着法用溶液原料を提供することにある。
本発明の別の目的は、ＭＯＣＶＤ装置が腐食しにくくＭＯＣＶＤ工程における排ガス処理を複雑にしない銅(II)のβ-ジケトネート錯体を含む有機金属化学蒸着法用溶液原料を提供することにある。
本発明の更に別の目的は、下地膜と堅牢に密着する高純度の銅薄膜を提供することにある。
【０００９】
【課題を解決するための手段】
請求項１に係る発明は、次の式（１）で示される銅(II)のβ-ジケトネート錯体をイソオクタン、 n- デカン、 n- ドデカン、ジメチルテトラヒドロフラン、酢酸イソブチル、酢酸ペンチル及び酢酸メチルからなる群より選ばれた１種又は２種以上の有機溶媒に溶解したことを特徴とする有機金属化学蒸着法用溶液原料である。
【００１０】
【化３】

但し、Ｒはイソプロピル基である。
【００１１】
請求項１に係る発明では、基本骨格から分岐した２つの原子団にそれぞれイソプロピル基を形成した配位子を配位させた銅錯体（以下、Ｃｕ(II)(ＤＭＨＤ)₂という。）であるため、構造安定性が高く、この銅錯体を有機溶媒に溶解させた溶液原料は長期保存に優れる。
【００１２】
請求項９に係る発明は、有機金属化学蒸着装置に備えられた原料容器に請求項１ないし８いずれか１項に記載の溶液原料を貯蔵し、基板をこの装置に備えられた成膜室に設置し、基板温度を１８０℃、原料気化温度を７０℃、成膜室圧力を約６６５Ｐａ、キャリアガスの流量を１００ｃｃｍに設定して、原料容器に貯蔵された溶液原料を気化させ、蒸気となった銅錯体を０．５ｃｃ／分の割合で成膜室内に供給して、成膜室内において銅錯体の蒸気を熱分解させ、これにより生成した銅又は銅合金を加熱された基板上に堆積させることにより、銅薄膜を形成することを特徴とする銅薄膜の製造方法である。
請求項１ないし８いずれか１項に記載の溶液原料を用い、上記条件で作製された銅薄膜は、溶液原料にフッ素が含有していないので剥離しにくい高純度の膜となる。
【００１３】
【発明の実施の形態】
次に本発明の実施の形態を説明する。
【００１４】
本発明の溶液原料は、前述した式（１）に示される二価の銅にβジケトネートを配位した化合物であるＣｕ(II)(ＤＭＨＤ)₂錯体を、以下に示す有機溶媒に溶解したＭＯＣＶＤ用の溶液原料である。このＣｕ(II)(ＤＭＨＤ)₂錯体と有機溶媒の配合比は任意であり、その使用用途や、有機溶媒の種類によって適宜調製することが好ましい。
【００１５】
本発明の溶液原料には、飽和炭化水素、環状エーテル及びエステル化合物からなる群より選ばれた１種又は２種以上の化合物が有機溶媒として使用される。具体的には、飽和炭化水素としては、イソオクタン、n-デカン及びn-ドデカンからなる群より選ばれた１種又は２種以上の化合物が挙げられる。環状エーテルとしては、ジメチルテトラヒドロフラン（以下、ジメチルＴＨＦという。）が挙げられる。エステル化合物としては、酢酸イソブチル、酢酸ペンチル及び酢酸メチルからなる群より選ばれた１種又は２種以上の化合物が挙げられる。
【００１６】
本発明の溶液原料には、更に安定化剤を含むことにより、より保存安定性の高い溶液原料として使用することができる。安定化剤としては、エチレングリコールエーテル類、クラウンエーテル類、ポリアミン類、環状ポリアミン類、β-ケトエステル類及びβ-ジケトン類からなる群より選ばれた１種又は２種以上の化合物が用いられる。具体的には、エチレングリコールエーテル類としては、グライム、ジグライム、トリグライム及びテトラグライムからなる群より選ばれた１種又は２種以上の化合物が挙げられる。クラウンエーテル類としては、１８-クラウン-６、ジシクロヘキシル-１８-クラウン-６、２４-クラウン-８、ジシクロヘキシル-２４-クラウン-８及びジベンゾ-２４-クラウン-８からなる群より選ばれた１種又は２種以上の化合物が挙げられる。ポリアミン類としては、エチレンジアミン、Ｎ,Ｎ’-テトラメチルメチレンジアミン、ジエチレントリアミン、トリメチレンテトラミン、テトラエチレンペンタミン、ペンタエチレンヘキサミン、１,１,４,７,７-ペンタメチルジエチレントリアミン及び１,１,４,７,１０,１０-ヘキサメチルトリエチレンテトラミンからなる群より選ばれた１種又は２種以上の化合物が挙げられる。環状ポリアミン類としては、サイクラム及びサイクレンからなる群より選ばれた１種又は２種の化合物が挙げられる。β-ケトエステル類又はβ-ジケトン類としては、アセト酢酸メチル、アセト酢酸エチル及びアセト酢酸-２-メトキシエチルからなる群より選ばれた１種又は２種以上の化合物が挙げられる。
【００１７】
本実施の形態では、ＭＯＣＶＤ法には、各溶液を加熱された気化器に供給し、ここで各溶液原料を瞬時に気化させ、成膜室に送る溶液気化ＣＶＤ法を用いる。
図１に示すように、ＭＯＣＶＤ装置は、成膜室１０と蒸気発生装置１１を備える。成膜室１０の内部にはヒータ１２が設けられ、ヒータ１２上には基板１３が保持される。この成膜室１０の内部は圧力センサー１４、コールドトラップ１５及びニードルバルブ１６を備える配管１７により真空引きされる。蒸気発生装置１１は原料容器１８を備え、この原料容器１８は溶液原料を貯蔵する。原料容器１８にはガス流量調節装置１９を介してキャリアガス導入管２１が接続され、また原料容器１８には供給管２２が接続される。供給管２２にはニードルバルブ２３及び溶液流量調節装置２４が設けられ、供給管２２は気化器２６に接続される。気化器２６にはニードルバルブ３１、ガス流量調節装置２８を介してキャリアガス導入管２９が接続される。気化器２６は更に配管２７により成膜室１０に接続される。また気化器２６には、ガスドレイン３２及びドレイン３３がそれぞれ接続される。
この装置では、Ｎ₂、Ｈｅ、Ａｒ等の不活性ガスからなるキャリアガスがキャリアガス導入管２１から原料容器１８内に導入され、原料容器１８に貯蔵されている溶液原料を供給管２２により気化器２６に搬送する。気化器２６で気化されて蒸気となった銅錯体は、更にキャリアガス導入管２８から気化器２６へ導入されたキャリアガスにより配管２７を経て成膜室１０内に供給される。成膜室１０内において、銅錯体の蒸気を熱分解させ、これにより生成した銅又は銅合金を加熱された基板１３上に堆積させて銅薄膜を形成する。
【００１８】
本発明の溶液原料を用いて作製された銅薄膜は、下地膜と堅牢に密着し、高純度である特長を有する。この銅薄膜は、例えばシリコン基板表面のＳｉＯ₂膜上にスパッタリング法又はＭＯＣＶＤ法により形成されたＴｉＮ膜又はＴａＮ膜上にＭＯＣＶＤ法により形成される。なお、本発明の基板はその種類を特に限定されるものではない。
【００１９】
【実施例】
次に本発明の実施例を比較例とともに詳しく説明する。
＜実施例１＞
先ず、塩化銅(I)１５０ｇをn-ヘキサン１００ｃｃを注ぎ、懸濁液とした。この懸濁液に２,６-ジメチル-３,５-ヘプタンジオン５０ｇをゆっくり滴下し、３０分間室温で攪拌した。次いで、反応液を７０℃で加熱還流した後、反応液を濾過した。得られた濾液を２０トールに減圧して３０分間保持することにより溶媒を留去した。溶媒の留去により残った残渣をn-ヘキサン１００ｃｃで再結晶することによりＣｕ(II)(ＤＭＨＤ)₂を得た。次に、得られたＣｕ(II)(ＤＭＨＤ)₂を有機溶媒であるイソオクタンに溶解してＭＯＣＶＤ法用溶液原料を調製した。
【００２０】
＜実施例２＞
有機溶媒をn-デカンにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例３＞
有機溶媒をn-ドデカンにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２１】
＜実施例４＞
有機溶媒をジメチルＴＨＦにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例５＞
有機溶媒を酢酸メチルにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例６＞
有機溶媒を酢酸ペンチルにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２２】
＜比較例１＞
銅錯体をＣｕ(II)(ｈｆａｃ)₂にし、有機溶媒をイソプロピルアルコールにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２＞
有機溶媒をエタノールにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例３＞
有機溶媒をn-オクタンにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２３】
＜比較例４＞
有機溶媒をシクロヘキサンにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例５＞
銅錯体をＣｕ(II)(ＤＰＭ)₂とし、有機溶媒は用いずに、この銅錯体をそのままＭＯＣＶＤ用溶液原料とした。
＜比較例６＞
有機溶媒をn-ブチルアルコールにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２４】
＜比較例７＞
有機溶媒をsec-ブチルアルコールにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例８＞
有機溶媒をＴＨＦにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２５】
＜比較例９＞
有機溶媒をジオキサンにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１０＞
有機溶媒を酢酸ブチルにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１１＞
有機溶媒を酢酸エチルにした以外は比較例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２６】
＜比較例１２＞
銅錯体をジ(2,2,6-トリメチルノナン-3,5-ジオナト)銅（以下、Ａ化合物という。）にし、有機溶媒をイソプロピルアルコールにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１３＞
銅錯体をジ(2,2-ジメチル-6-エチルデカン-3,5-ジオナト)銅（以下、Ｂ化合物という。）にし、有機溶媒をエタノールにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２７】
＜比較例１４＞
有機溶媒をn-オクタンにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１５＞
有機溶媒をシクロヘキサンにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１６＞
有機溶媒をＴＨＦにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２８】
＜比較例１７＞
有機溶媒をＴＨＦにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１８＞
有機溶媒を酢酸ブチルにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例１９＞
有機溶媒を酢酸ブチルにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００２９】
＜比較試験１＞
実施例１〜６及び比較例１〜１９で得られた溶液原料に含まれる銅錯体の濃度をそれぞれ０．１モル濃度に調整し、それぞれ５種類用意した。基板として、基板表面のＳｉＯ₂膜（厚さ５０００Å）上にスパッタリング法によりＴｉＮ膜（厚さ３０ｎｍ）を形成したシリコン基板を用意した。
用意した基板を図１に示すＭＯＣＶＤ装置の成膜室に設置し、基板温度を１８０℃とした。気化温度を７０℃、圧力を５ｔｏｒｒ即ち約６６５Ｐａにそれぞれ設定した。キャリアガスとしてＡｒガスを用い、その流量を１００ｃｃｍとした。溶液原料を０．５ｃｃ／分の割合で供給し、１、５、１０、２０及び３０分となったときにそれぞれ１種類ごとに成膜室より取り出し、基板上に成膜された銅薄膜について以下に示す試験を行った。
【００３０】
(1) 膜厚測定
成膜を終えた基板上の銅薄膜を断面ＳＥＭ（走査型電子顕微鏡）像から膜厚を測定した。
【００３１】
(2) 剥離試験
各成膜時間で取り出した銅薄膜を形成した基板に対して剥離試験（ＪＩＳ Ｋ ５６００−５−６）を行った。具体的には、先ず、基板上の銅薄膜にこの膜を貫通するように縦横それぞれ６本づつ等間隔に切込みを入れて格子パターンを基板に形成した。次に、形成した格子パターンの双方の対角線に沿って柔らかいはけを用いて前後にブラッシングした。
【００３２】
(3) 熱安定性評価試験
図２に示す試験装置を用いて以下の試験を行った。この図２に示す装置は、図１に示すＭＯＣＶＤ装置の成膜室を取り除いた構成を有する。
先ず、室温で７０℃に加熱した気化器２６まで溶液原料を搬送し、５トールの減圧下で７０℃に加熱して溶液原料を気化させ、その後に気化器２６下段のポンプ側に設けられたコールドトラップ１５にて気化後の化合物を捕獲した。装置内に投入した原料に対する捕獲量からトラップ回収率を算出した。また、圧力センサーにより気化器内部における圧力上昇を測定した。例えば、表中の数値が６０％閉塞ならば、５Ｔｏｒｒの１．６０倍の圧力が気化器内で生じていることを表す。
【００３３】
実施例１〜６を表１に、比較例１〜６を表２に、比較例７〜１２を表３に、比較例１３〜１９を表４にそれぞれ得られた試験結果を示す。
【００３４】
【表１】

【００３５】
【表２】

【００３６】
【表３】

【００３７】
【表４】

表１〜表４より明らかなように、比較例１〜１９の溶液原料を用いて成膜された銅薄膜は成膜時間当たりの膜厚にばらつきがあり、成膜再現性が悪いことが判る。また成膜速度も非常に遅い。また密着性評価試験では、殆どのサンプルにおいて基板表面から銅薄膜が剥離してしまっていた。熱安定性評価試験では、トラップ回収率が低く、大部分が装置内部に付着してしまったと考えられる。また気化器内部の圧力上昇値も成膜時間が長くなるにつれて上昇しており、分解物が気化器内部や配管内部に付着して圧力上昇したと考えられる。これに対して実施例１〜６の溶液原料を用いて作製された銅薄膜は、成膜時間が進むに従って膜厚も厚くなっており、成膜安定性が高いことが判る。密着性評価試験では、１００回中９２〜９９回の数値を示し、どの実施例においても殆どの銅薄膜が剥離せず、非常に密着性が高いことが判る。熱安定性評価試験では、５８〜７０％範囲内の高いトラップ回収率を示し、気化器内部の圧力上昇値も１〜２％程度と殆ど閉塞するおそれがない。
【００３８】
＜実施例７＞
有機溶媒をイソオクタンにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例８＞
有機溶媒をn-デカンにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００３９】
＜実施例９＞
有機溶媒をジメチルＴＨＦにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例１０＞
有機溶媒を酢酸メチルにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜実施例１１＞
有機溶媒を酢酸ペンチルにした以外は実施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００４０】
＜比較例２０＞
有機溶媒をn-オクタンにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２１＞
有機溶媒をn-デカンにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２２＞
有機溶媒をイソオクタンにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００４１】
＜比較例２３＞
有機溶媒をシクロヘキサンにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２４＞
有機溶媒をイソプロピルアルコールにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２５＞
有機溶媒をエタノールにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００４２】
＜比較例２６＞
有機溶媒をＴＨＦにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２７＞
有機溶媒をジオキサンにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２８＞
有機溶媒を酢酸ブチルにした以外は比較例１２と同様にしてＭＯＣＶＤ用溶液原料を調製した。
＜比較例２９＞
有機溶媒を酢酸ブチルにした以外は比較例１３と同様にしてＭＯＣＶＤ用溶液原料を調製した。
【００４３】
＜比較試験２＞
実施例７〜１１及び比較例２０〜２９で得られた溶液原料に含まれる銅錯体の濃度をそれぞれ０．２モル濃度に調整し、それぞれ５種類用意した。基板は比較試験１で使用したシリコン基板と同様のものを用意した。
用意した基板をＭＯＣＶＤ装置の成膜室に設置し、基板温度を４５０℃とした。気化温度を２００℃、圧力を９Ｔｏｒｒ即ち１１９７Ｐａにそれぞれ設定した。キャリアガスとしてＡｒガスを用い、その流量を１００ｃｃｍとした。
溶液原料を０．０５ｃｃ／分の割合で供給し、１、５、１０、２０及び３０分となったときにそれぞれ１種類ごとに成膜室より取り出し、基板上に成膜された銅薄膜について以下に示す試験を行った。
【００４４】
(1) 膜厚測定
成膜を終えた基板上の銅薄膜を断面ＳＥＭ（走査型電子顕微鏡）像から膜厚を測定した。
【００４５】
(2) 剥離試験
各成膜時間で取り出した銅薄膜を形成した基板に対して剥離試験（ＪＩＳ Ｋ ５６００−５−６）を行った。具体的には、先ず、基板上の銅薄膜にこの膜を貫通するように縦横それぞれ６本づつ等間隔に切込みを入れて格子パターンを基板に形成した。次に、形成した格子パターンの双方の対角線に沿って柔らかいはけを用いて前後にブラッシングした。
【００４６】
(3) 熱安定性評価試験
先ず、室温で２００℃に加熱した気化器２６まで溶液原料を搬送し、９トールの減圧下で２００℃に加熱して溶液原料を気化させ、その後に気化器２６下段のポンプ側に設けられたコールドトラップ１５にて気化後の化合物を捕獲した。装置内に投入した原料に対する捕獲量からトラップ回収率を算出した。また、圧力センサーにより気化器内部における圧力上昇を測定した。
【００４７】
実施例７〜１１を表５に、比較例２０〜２４を表６に、比較例２５〜２９を表７にそれぞれ示す。
【００４８】
【表５】

【００４９】
【表６】

【００５０】
【表７】

表５〜表７より明らかなように、比較例２０〜２９の溶液原料を用いて成膜された銅薄膜は成膜時間当たりの膜厚にばらつきがあり、成膜再現性が悪いことが判る。また成膜速度も非常に遅い。また密着性評価試験では、殆どのサンプルにおいて基板表面から銅薄膜が剥離してしまっていた。熱安定性評価試験では、トラップ回収率が低く、大部分が装置内部に付着してしまったと考えられる。また気化器内部の圧力上昇値も成膜時間が長くなるにつれて上昇しており、分解物が気化器内部や配管内部に付着して圧力上昇したと考えられる。これに対して実施例７〜１１の溶液原料を用いて作製された銅薄膜は、成膜時間が進むに従って膜厚も厚くなっており、成膜安定性が高いことが判る。密着性評価試験では、１００回中９５〜９９回の数値を示し、どの実施例においても殆どの銅薄膜が剥離せず、非常に密着性が高いことが判る。熱安定性評価試験では、５８〜６８％範囲内の高いトラップ回収率を示し、気化器内部の圧力上昇値も１％程度と殆ど閉塞するおそれがない。
【００５１】
【発明の効果】
以上述べたように、本発明の上記式（１）に示される銅(II)のβ-ジケトネート錯体を有機溶媒に溶解した溶液原料は、熱安定性に優れ、保存状態で分解しにくく寿命が長い。また配位子がＣ、Ｈ、Ｏよりなり、ｈｆａｃのようにＦ（フッ素）を含まないため、ＭＯＣＶＤ装置が腐食しにくくＭＯＣＶＤ工程における排ガス処理を複雑にしない。本発明の溶液原料を用いてＭＯＣＶＤ法により作製された銅薄膜は、下地膜と堅牢に密着する高純度の膜となる。
【図面の簡単な説明】
【図１】 ＭＯＣＶＤ装置の概略図。
【図２】 本発明の実施例に使用される装置を示す概略図。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a copper (II) β-diketonate complex for producing a copper (Cu) thin film used for wiring of a semiconductor device by a metal organic chemical vapor deposition (hereinafter referred to as MOCVD) method. It is related with the solution raw material for metal organic chemical vapor deposition, and the copper thin film produced using the same.
[0002]
[Prior art]
Copper and copper-based alloys are applied as LSI wiring materials because of their high electrical conductivity and electromigration resistance. Moreover, the composite metal oxide containing copper is applied as a functional ceramic material such as a high-temperature superconductor. Examples of methods for producing copper-based thin films such as copper, copper-containing alloys, and copper-containing composite metal oxides include sputtering, ion plating, and coating pyrolysis, but the processing dimensions become fine. Accordingly, the CVD method and the MOCVD method using an organometallic compound have been studied as the optimum thin film manufacturing process because of excellent composition controllability, step coverage, and step embedding property, and compatibility with an LSI process.
[0003]
Cu (II) (hfac) ₂ complex, that is, copper (II) hexafluoroacetylacetonate complex has been used as an organic copper compound for imparting copper to the IC substrate and the surface by this MOCVD method. However, this Cu (II) (hfac) ₂ complex is not practical because it leaves contaminants in the deposited copper and it is necessary to use a relatively high temperature to decompose the complex to form copper. And it did not have sufficient characteristics.
[0004]
Therefore, the use of a monovalent Cu (I) (hfac) complex has been studied. For example, a Cu (I) tmvs · hfac complex which is liquid at room temperature, that is, a copper (I) hexafluoroacetylacetonate trimethylvinylsilane complex is disclosed. (US Pat. No. 5,322,712). This Cu (I) tmvs · hfac complex is very useful because it can be used at a relatively low temperature of about 200 ° C. However, this complex is very expensive, and is very unstable in the atmosphere, so it is very unstable and easily decomposes at room temperature, resulting in precipitation of copper metal and by-product Cu (II) (hfac) ₂ Deterioration is remarkable. For this reason, it is difficult to stably supply this copper complex at the time of film formation, and the reproducibility of film formation is also poor.
In addition, since hfac, which is a ligand, contains fluorine (F), the MOCVD apparatus is easily corroded and exhaust gas treatment in the MOCVD process is complicated. Furthermore, when a copper film is formed by MOCVD using an organic copper compound containing fluorine such as hfac, when a desired copper thin film is formed, not only fluorine is taken into the copper thin film as an impurity, There is a problem in that fluorine remains on the underlayer interface of the wafer, thereby reducing the adhesion to the underlayer.
[0005]
In order to solve the above-mentioned problems, a chemical vapor deposition raw material comprising a β-diketonate complex of copper (II) represented by the following formula (2) is disclosed (Japanese Patent Laid-Open No. 2001-181840).
[0006]
[Chemical 2]

(In the formula, R represents an isopropyl group or a tertiary butyl group, R ¹ represents a methyl group or an ethyl group, and R ² represents a propyl group or a butyl group.)
This copper raw material is liquid at room temperature and does not contain any elements that may affect the production of thin films such as halogen elements and nitrogen elements in the molecule, so it is suitable for various CVD methods, and is also an existing solid copper (II) It has the same thermal and chemical stability as a copper raw material for CVD comprising a complex.
[0007]
[Problems to be solved by the invention]
However, the copper raw material represented by the above formula (2) in Japanese Patent Application Laid-Open No. 2001-181840 is liquid at room temperature, but its viscosity is very high. To supply this copper raw material to the MOCVD apparatus, it must be supplied at a high pressure. As a result, there remains a problem in film formability. Moreover, even if this copper raw material is dissolved in a solution and supplied to the MOCVD apparatus as a solution raw material, the decomposition temperature of this copper raw material is about 450 ° C., which is the decomposition temperature of organic copper compounds that have been generally used conventionally. Since it is very high in comparison, there is a problem that it is difficult to form a film. Moreover, since the copper raw material represented by the above formula (2) has an unbalanced structure in which the molecular structure is biased, sufficient film formation stability could not be obtained.
[0008]
An object of the present invention is to provide a solution raw material for a metal organic chemical vapor deposition method containing a β-diketonate complex of copper (II) which has excellent thermal stability and is difficult to decompose in a storage state and has a long life.
Another object of the present invention is to provide a solution raw material for metal organic chemical vapor deposition containing a β-diketonate complex of copper (II) which does not easily corrode the MOCVD apparatus and does not complicate the exhaust gas treatment in the MOCVD process.
Still another object of the present invention is to provide a high-purity copper thin film that adheres firmly to a base film.
[0009]
[Means for Solving the Problems]
The invention according to claim 1 is a copper (II) β-diketonate complex represented by the following formula (1): isooctane, n- decane, n- dodecane, dimethyltetrahydrofuran, isobutyl acetate, pentyl acetate and methyl acetate. A solution raw material for metal organic chemical vapor deposition characterized by being dissolved in one or more organic solvents selected from the group .
[0010]
[Chemical 3]

However, R is an isopropyl group.
[0011]
The invention according to claim 1 is a copper complex (hereinafter referred to as Cu (II) (DMHD) ₂ ) in which a ligand having an isopropyl group is coordinated to two atomic groups branched from the basic skeleton. Therefore, the structure stability is high, and the solution raw material in which this copper complex is dissolved in an organic solvent is excellent in long-term storage.
[0012]
The invention according to claim 9 stores the solution raw material according to any one of claims 1 to 8 in a raw material container provided in a metal organic chemical vapor deposition apparatus, and a substrate in a film forming chamber provided in the apparatus. It is installed, the substrate temperature is set to 180 ° C., the material vaporization temperature is set to 70 ° C., the film forming chamber pressure is set to about 665 Pa, the carrier gas flow rate is set to 100 ccm, and the solution material stored in the material container is vaporized to become vapor. The copper complex is supplied into the film formation chamber at a rate of 0.5 cc / min, the vapor of the copper complex is thermally decomposed in the film formation chamber, and the produced copper or copper alloy is deposited on the heated substrate. By this, it is a manufacturing method of the copper thin film characterized by forming a copper thin film .
A copper thin film produced using the solution raw material according to any one of claims 1 to 8 under the above conditions becomes a high-purity film that is difficult to peel off because the solution raw material does not contain fluorine.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described.
[0014]
The solution raw material of the present invention is an MOCVD in which a Cu (II) (DMHD) ₂ complex, which is a compound in which β-diketonate is coordinated to the divalent copper represented by the above formula (1), is dissolved in the organic solvent shown below. Solution raw material for use. The mixing ratio of the Cu (II) (DMHD) ₂ complex and the organic solvent is arbitrary, and it is preferable to prepare appropriately depending on the intended use and the type of the organic solvent.
[0015]
The raw material solution of the present invention, a saturated hydrocarbon, one or more compounds selected from the group consisting of ring-like ethers and ester compounds are used as organic solvents. Specifically, the saturated hydrocarbons, Lee Sookutan, one or more compounds selected from the group consisting of n- decane and n- dodecane. The ring-shaped ether, di-methyl tetrahydrofuran (hereinafter, referred to as dimethyl THF.) And the like. The ester compounds, isobutyl acetate acid, one or more compounds selected from the group consisting of pentyl acetate and methyl acetate and the like.
[0016]
The solution raw material of the present invention can be used as a solution raw material having higher storage stability by further containing a stabilizer. As the stabilizer, one or more compounds selected from the group consisting of ethylene glycol ethers, crown ethers, polyamines, cyclic polyamines, β-ketoesters and β-diketones are used. Specifically, ethylene glycol ethers include one or more compounds selected from the group consisting of glyme, diglyme, triglyme and tetraglyme. The crown ethers are one selected from the group consisting of 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8 and dibenzo-24-crown-8. Or 2 or more types of compounds are mentioned. Polyamines include ethylenediamine, N, N′-tetramethylmethylenediamine, diethylenetriamine, trimethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7-pentamethyldiethylenetriamine and 1,1,1,4. Examples thereof include one or more compounds selected from the group consisting of 4,7,10,10-hexamethyltriethylenetetramine. Examples of the cyclic polyamines include one or two compounds selected from the group consisting of cyclam and cyclen. Examples of β-ketoesters or β-diketones include one or more compounds selected from the group consisting of methyl acetoacetate, ethyl acetoacetate, and 2-methoxyethyl acetoacetate.
[0017]
In this embodiment, the MOCVD method uses a solution vaporization CVD method in which each solution is supplied to a heated vaporizer, where each solution raw material is instantaneously vaporized and sent to a film formation chamber.
As shown in FIG. 1, the MOCVD apparatus includes a film formation chamber 10 and a vapor generator 11. A heater 12 is provided inside the film forming chamber 10, and a substrate 13 is held on the heater 12. The inside of the film forming chamber 10 is evacuated by a pipe 17 including a pressure sensor 14, a cold trap 15 and a needle valve 16. The steam generator 11 includes a raw material container 18, which stores the solution raw material. A carrier gas introduction pipe 21 is connected to the raw material container 18 through a gas flow rate control device 19, and a supply pipe 22 is connected to the raw material container 18. The supply pipe 22 is provided with a needle valve 23 and a solution flow rate adjusting device 24, and the supply pipe 22 is connected to a vaporizer 26. A carrier gas introduction pipe 29 is connected to the vaporizer 26 via a needle valve 31 and a gas flow rate control device 28. The vaporizer 26 is further connected to the film forming chamber 10 by a pipe 27. A gas drain 32 and a drain 33 are connected to the vaporizer 26, respectively.
In this apparatus, a carrier gas composed of an inert gas such as N ₂ , He, Ar is introduced into the raw material container 18 from the carrier gas introduction pipe 21, and the solution raw material stored in the raw material container 18 is vaporized by the supply pipe 22. To the container 26. The copper complex that has been vaporized by the vaporizer 26 to become vapor is further supplied into the film forming chamber 10 through the pipe 27 by the carrier gas introduced into the vaporizer 26 from the carrier gas introduction pipe 28. In the film forming chamber 10, the vapor of the copper complex is pyrolyzed, and the copper or copper alloy generated thereby is deposited on the heated substrate 13 to form a copper thin film.
[0018]
The copper thin film produced using the solution raw material of the present invention has a feature that it is firmly adhered to the base film and has high purity. This copper thin film is formed by, for example, MOCVD on a TiN film or TaN film formed by sputtering or MOCVD on a SiO ₂ film on the surface of a silicon substrate. The type of the substrate of the present invention is not particularly limited.
[0019]
【Example】
Next, examples of the present invention will be described in detail together with comparative examples.
<Example 1>
First, 150 g of copper (I) chloride was poured into 100 cc of n-hexane to prepare a suspension. To this suspension, 50 g of 2,6-dimethyl-3,5-heptanedione was slowly added dropwise and stirred at room temperature for 30 minutes. Next, the reaction solution was heated to reflux at 70 ° C., and then the reaction solution was filtered. The resulting filtrate was depressurized to 20 torr and held for 30 minutes to distill off the solvent. Cu (II) (DMHD) ₂ was obtained by recrystallizing the residue remaining after evaporation of the solvent with 100 cc of n-hexane. Next, the obtained Cu (II) (DMHD) ₂ was dissolved in isooctane , which is an organic solvent, to prepare a solution raw material for MOCVD.
[0020]
<Example 2 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was n-decane.
<Example 3 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was n-dodecane.
[0021]
<Example 4 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was dimethyl THF .
<Example 5 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that methyl acetate was used as the organic solvent.
<Example 6 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was pentyl acetate.
[0022]
<Comparative Example 1>
A solution material for MOCVD was prepared in the same manner as in Example 1 except that the copper complex was Cu (II) (hfac) ₂ and the organic solvent was isopropyl alcohol.
<Comparative example 2>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was ethanol.
<Comparative Example 3>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was changed to n-octane.
[0023]
<Comparative example 4>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was cyclohexane.
<Comparative Example 5>
The copper complex was Cu (II) (DPM) _2, and this copper complex was directly used as a solution raw material for MOCVD without using an organic solvent.
<Comparative Example 6>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was n-butyl alcohol.
[0024]
<Comparative Example 7>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was sec-butyl alcohol.
<Comparative Example 8>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was THF.
[0025]
<Comparative Example 9>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was dioxane.
<Comparative Example 10>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was butyl acetate.
<Comparative Example 11>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 1 except that the organic solvent was ethyl acetate.
[0026]
<Comparative Example 12>
A solution for MOCVD in the same manner as in Example 1 except that the copper complex is di (2,2,6-trimethylnonane-3,5-dionato) copper (hereinafter referred to as A compound) and the organic solvent is isopropyl alcohol. The raw material was prepared.
<Comparative Example 13>
A solution for MOCVD in the same manner as in Example 1 except that the copper complex is di (2,2-dimethyl-6-ethyldecane-3,5-dionato) copper (hereinafter referred to as B compound) and the organic solvent is ethanol. The raw material was prepared.
[0027]
<Comparative example 14>
A solution raw material for MOCVD was prepared in the same manner as Comparative Example 12 except that the organic solvent was changed to n-octane.
<Comparative Example 15>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 13 except that the organic solvent was cyclohexane.
<Comparative Example 16>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was THF.
[0028]
<Comparative Example 17>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 13 except that the organic solvent was THF.
<Comparative Example 18>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was butyl acetate.
<Comparative Example 19>
A solution raw material for MOCVD was prepared in the same manner as Comparative Example 13 except that the organic solvent was butyl acetate.
[0029]
<Comparison test 1>
The concentration of the copper complex contained in the solution raw materials obtained in Examples 1 to 6 and Comparative Examples 1 to 19 was adjusted to 0.1 molar concentration, and five types were prepared. As a substrate, a silicon substrate was prepared in which a TiN film (thickness 30 nm) was formed by sputtering on a SiO ₂ film (thickness 5000 mm) on the substrate surface.
The prepared substrate was placed in the film formation chamber of the MOCVD apparatus shown in FIG. 1, and the substrate temperature was 180 ° C. The vaporization temperature was set to 70 ° C., and the pressure was set to 5 torr, that is, about 665 Pa. Ar gas was used as a carrier gas, and the flow rate was set to 100 ccm. Regarding the copper thin film formed on the substrate by supplying the solution raw material at a rate of 0.5 cc / min and taking it out from the film forming chamber one by one at 1, 5, 10, 20 and 30 minutes. The following tests were conducted.
[0030]
(1) Film thickness measurement The film thickness of the copper thin film on the substrate after film formation was measured from a cross-sectional SEM (scanning electron microscope) image.
[0031]
(2) Peel test A peel test (JIS K 5600-5-6) was performed on the substrate on which the copper thin film taken out at each film formation time was formed. Specifically, first, a lattice pattern was formed on the substrate by cutting the copper thin film on the substrate at six equal intervals vertically and horizontally so as to penetrate the film. Next, brushing was performed back and forth using a soft brush along the diagonal lines of both of the formed lattice patterns.
[0032]
(3) Thermal stability evaluation test The following test was conducted using the test apparatus shown in FIG. The apparatus shown in FIG. 2 has a configuration in which the film formation chamber of the MOCVD apparatus shown in FIG. 1 is removed.
First, the solution raw material was conveyed to the vaporizer 26 heated to 70 ° C. at room temperature, and heated to 70 ° C. under a reduced pressure of 5 Torr to vaporize the solution raw material, and then provided on the pump side of the lower stage of the vaporizer 26. The vaporized compound was captured by the cold trap 15. The trap recovery rate was calculated from the amount of capture of the raw material charged into the apparatus. In addition, the pressure rise inside the vaporizer was measured with a pressure sensor. For example, if the numerical value in the table is 60% occluded, it represents that a pressure of 1.60 times 5 Torr is generated in the vaporizer.
[0033]
Example 1-6 in Table 1, the ratio Comparative Examples 1-6 in Table 2, Comparative Examples 7 to 12 in Table 3 shows the test results obtained in Tables 4 and Comparative Examples 13-19.
[0034]
[Table 1]

[0035]
[Table 2]

[0036]
[Table 3]

[0037]
[Table 4]

As is clear from Tables 1 to 4, it can be seen that the copper thin films formed using the solution raw materials of Comparative Examples 1 to 19 have variations in film thickness per film formation time, and the film formation reproducibility is poor. . Also, the film formation rate is very slow. In the adhesion evaluation test, the copper thin film was peeled off from the substrate surface in most samples. In the thermal stability evaluation test, it is considered that the trap recovery rate is low and most of the trap has adhered to the inside of the apparatus. Further, the pressure increase value inside the vaporizer also increases as the film formation time becomes longer, and it is considered that the decomposition product adhered to the inside of the vaporizer and the inside of the pipe and the pressure increased. On the other hand, it can be seen that the copper thin films prepared using the solution raw materials of Examples 1 to 6 are thicker as the film formation time progresses, and the film formation stability is higher. In the adhesion evaluation test, a numerical value of 92 to 99 times out of 100 times is shown, and it can be seen that almost all copper thin films are not peeled off in any of the examples, and the adhesion is very high. In the thermal stability evaluation test, a high trap recovery rate in the range of 58 to 70% is shown, and the pressure increase value inside the vaporizer is about 1 to 2%, and there is almost no possibility of clogging.
[0038]
<Example 7 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was isooctane .
<Example 8 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was n-decane.
[0039]
<Example 9 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was dimethyl THF .
<Example 10 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that methyl acetate was used as the organic solvent.
<Example 11 >
A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was pentyl acetate.
[0040]
<Comparative Example 20>
A solution raw material for MOCVD was prepared in the same manner as Comparative Example 12 except that the organic solvent was changed to n-octane.
<Comparative Example 21>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was n-decane.
<Comparative Example 22>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was isooctane.
[0041]
<Comparative Example 23>
A solution raw material for MOCVD was prepared in the same manner as Comparative Example 12 except that the organic solvent was cyclohexane.
<Comparative Example 24>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was isopropyl alcohol.
<Comparative Example 25>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 13 except that ethanol was used as the organic solvent.
[0042]
<Comparative Example 26>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was THF.
<Comparative Example 27>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 13 except that the organic solvent was dioxane.
<Comparative example 28>
A solution raw material for MOCVD was prepared in the same manner as in Comparative Example 12 except that the organic solvent was butyl acetate.
<Comparative Example 29>
A solution raw material for MOCVD was prepared in the same manner as Comparative Example 13 except that the organic solvent was butyl acetate.
[0043]
<Comparison test 2>
The concentration of the copper complex contained in the solution raw materials obtained in Examples 7 to 11 and Comparative Examples 20 to 29 was adjusted to 0.2 molar concentration, and 5 types were prepared. The same substrate as the silicon substrate used in Comparative Test 1 was prepared.
The prepared substrate was placed in the film formation chamber of the MOCVD apparatus, and the substrate temperature was set to 450 ° C. The vaporization temperature was set to 200 ° C., and the pressure was set to 9 Torr, that is, 1197 Pa. Ar gas was used as a carrier gas, and the flow rate was set to 100 ccm.
Regarding the copper thin film formed on the substrate by supplying the solution raw material at a rate of 0.05 cc / min and taking it out from the film forming chamber one by one when 1, 5, 10, 20 and 30 minutes are reached. The following tests were conducted.
[0044]
(1) Film thickness measurement The film thickness of the copper thin film on the substrate after film formation was measured from a cross-sectional SEM (scanning electron microscope) image.
[0045]
(2) Peel test A peel test (JIS K 5600-5-6) was performed on the substrate on which the copper thin film taken out at each film formation time was formed. Specifically, first, a lattice pattern was formed on the substrate by cutting the copper thin film on the substrate at six equal intervals vertically and horizontally so as to penetrate the film. Next, brushing was performed back and forth using a soft brush along the diagonal lines of both of the formed lattice patterns.
[0046]
(3) Thermal stability evaluation test First, the solution raw material is transported to a vaporizer 26 heated to 200 ° C. at room temperature, and heated to 200 ° C. under a reduced pressure of 9 Torr to vaporize the solution raw material, and then the vaporizer 26 The vaporized compound was captured by a cold trap 15 provided on the lower pump side. The trap recovery rate was calculated from the amount of capture of the raw material charged into the apparatus. In addition, the pressure rise inside the vaporizer was measured with a pressure sensor.
[0047]
Examples 7-11 in Table 5, the ratio Comparative Examples 20-24 in Table 6, the ratio Comparative Examples 25-29 are shown in Table 7.
[0048]
[Table 5]

[0049]
[Table 6]

[0050]
[Table 7]

As is apparent from Tables 5 to 7, it can be seen that the copper thin films formed using the solution raw materials of Comparative Examples 20 to 29 have variations in film thickness per film formation time, and the film formation reproducibility is poor. . Also, the film formation rate is very slow. In the adhesion evaluation test, the copper thin film was peeled off from the substrate surface in most samples. In the thermal stability evaluation test, it is considered that the trap recovery rate is low and most of the trap has adhered to the inside of the apparatus. Further, the pressure increase value inside the vaporizer also increases as the film formation time becomes longer, and it is considered that the decomposition product adhered to the inside of the vaporizer and the inside of the pipe and the pressure increased. On the other hand, it can be seen that the copper thin films prepared using the solution raw materials of Examples 7 to 11 are thicker as the film formation time progresses, and the film formation stability is higher. In the adhesion evaluation test, a numerical value of 95 to 99 times out of 100 is shown, and it can be seen that most of the copper thin film does not peel in any of the examples, and the adhesion is very high. In the thermal stability evaluation test, a high trap recovery rate in the range of 58 to 68% is shown, and the pressure increase value inside the vaporizer is about 1%, and there is almost no possibility of clogging.
[0051]
【The invention's effect】
As described above, the solution raw material in which the copper (II) β-diketonate complex represented by the above formula (1) of the present invention is dissolved in an organic solvent is excellent in thermal stability, hardly decomposes in a storage state, and has a long life. long. Further, since the ligand is made of C, H, and O and does not contain F (fluorine) like hfac, the MOCVD apparatus is hardly corroded and does not complicate the exhaust gas treatment in the MOCVD process. The copper thin film produced by the MOCVD method using the solution raw material of the present invention becomes a high-purity film that adheres firmly to the base film.
[Brief description of the drawings]
FIG. 1 is a schematic view of an MOCVD apparatus.
FIG. 2 is a schematic view showing an apparatus used in an embodiment of the present invention.

Claims (9)

A copper (II) β-diketonate complex represented by the following formula (1) is selected from the group consisting of isooctane, n- decane, n- dodecane, dimethyltetrahydrofuran, isobutyl acetate, pentyl acetate and methyl acetate, or A solution raw material for metal organic chemical vapor deposition characterized by being dissolved in two or more organic solvents.

However, R is an isopropyl group . Claim 1 Symbol placement of raw material solution further comprises a stabilizer. Ethylene glycol ethers stabilizer, crown ethers, polyamines, cyclic polyamines, beta-keto esters and claim 2, wherein the one or more compounds selected from the group consisting of beta-diketone Solution raw material. The solution raw material according to claim 3, wherein the ethylene glycol ether is one or more compounds selected from the group consisting of glyme, diglyme, triglyme and tetraglyme. One or two crown ethers selected from the group consisting of 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8 and dibenzo-24-crown-8 The solution raw material according to claim 3 , which is a compound of at least one species. Polyamines are ethylenediamine, N, N′-tetramethylmethylenediamine, diethylenetriamine, trimethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7-pentamethyldiethylenetriamine and 1,1,4, The solution raw material according to claim 3 , which is one or more compounds selected from the group consisting of 7,10,10-hexamethyltriethylenetetramine. The solution raw material according to claim 3, wherein the cyclic polyamine is one or two compounds selected from the group consisting of cyclam and cyclen. The solution raw material according to claim 3, wherein the β-ketoester or β-diketone is one or more compounds selected from the group consisting of methyl acetoacetate, ethyl acetoacetate and 2-methoxyethyl acetoacetate. The solution raw material according to any one of claims 1 to 8 is stored in a raw material container provided in a metal organic chemical vapor deposition apparatus , the substrate is placed in a film forming chamber provided in the apparatus, and the substrate temperature is set to 180 ° C. The raw material vaporization temperature is set to 70 ° C., the film forming chamber pressure is set to about 665 Pa, the flow rate of the carrier gas is set to 100 ccm, the solution raw material stored in the raw material container is vaporized, and the vaporized copper complex is 0.5 cc. By supplying into the film formation chamber at a rate of / min, pyrolyzing the vapor of the copper complex in the film formation chamber, and depositing the copper or copper alloy generated thereby on the heated substrate, A method for producing a copper thin film, comprising forming a thin film.

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