JP2003342732A - Solution raw material for organometallic chemical vapor deposition method containing tantalum complex and tantalum-containing thin film produced by using the same - Google Patents
Solution raw material for organometallic chemical vapor deposition method containing tantalum complex and tantalum-containing thin film produced by using the sameInfo
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- JP2003342732A JP2003342732A JP2002144849A JP2002144849A JP2003342732A JP 2003342732 A JP2003342732 A JP 2003342732A JP 2002144849 A JP2002144849 A JP 2002144849A JP 2002144849 A JP2002144849 A JP 2002144849A JP 2003342732 A JP2003342732 A JP 2003342732A
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- raw material
- tantalum
- solution raw
- group
- thin film
- Prior art date
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、半導体装置の配線
に用いられる銅（Ｃｕ）薄膜を形成加工する際の下地バ
リアとしてのタンタル含有薄膜を形成するための溶液原
料に関する。更に詳しくは有機金属化学蒸着（Metal Or
ganic Chemical Vapor Deposition、以下、ＭＯＣＶＤ
という。）法によりタンタル含有薄膜を形成するための
タンタル錯体を含む溶液原料及びこれから作られたタン
タル含有薄膜に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solution raw material for forming a tantalum-containing thin film as a base barrier when forming and processing a copper (Cu) thin film used for wiring of a semiconductor device. For more details, see Metal Or
ganic Chemical Vapor Deposition, MOCVD
Say. The present invention relates to a solution raw material containing a tantalum complex for forming a tantalum-containing thin film by the method) and a tantalum-containing thin film made therefrom.
【０００２】[0002]
【従来の技術】銅及び銅系合金は、高い導電性、エレク
トロマイグレーション耐性からＬＳＩの配線材料として
応用されている。銅はシリコン酸化膜を通じて基板内に
簡単に拡散してしまう問題があるため、銅により配線を
行う際には、銅薄膜とシリコン酸化膜の間に下地バリア
メタル薄膜を形成し、銅の拡散を防止している。2. Description of the Related Art Copper and copper-based alloys are used as wiring materials for LSIs because of their high conductivity and resistance to electromigration. Since copper has a problem of easily diffusing into the substrate through the silicon oxide film, when wiring is made of copper, a base barrier metal thin film is formed between the copper thin film and the silicon oxide film to diffuse the copper. To prevent.
【０００３】この種の下地バリアメタル薄膜として窒化
チタン膜よりバリア性が高い窒化タンタル膜が知られて
いる。これまでＭＯＣＶＤ法で窒化タンタル膜を作製す
る報告例は少なく、最近になって固体のペンタジメチル
アミノタンタル（Ｔａ(Ｎ(ＣＨ3)2)5；以下、ＰＤＭＡ
Ｔという。）やペンタジエチルアミノタンタル（Ｔａ
(Ｎ(Ｃ2Ｈ5)2)5；以下、ＰＤＥＡＴという。）をアルコ
ールに溶解した溶液原料を用いて窒化タンタル膜を作製
する試みがなされている。As this type of underlying barrier metal thin film, a tantalum nitride film having a barrier property higher than that of a titanium nitride film is known. Up to now, there have been few reports of forming a tantalum nitride film by the MOCVD method, and recently, solid pentadimethylaminotantalum (Ta (N (CH 3 ) 2 ) 5 ; hereinafter referred to as PDMA
T. ) And pentadiethylamino tantalum (Ta
(N (C 2 H 5 ) 2 ) 5 ; hereinafter referred to as PDEAT. Attempts have been made to produce a tantalum nitride film using a solution raw material obtained by dissolving) in alcohol.
【０００４】[0004]
【発明が解決しようとする課題】しかし、上記溶液原料
で窒化タンタル膜をＭＯＣＶＤ法で作製すると、原料に
含まれる化合物が熱的安定性に乏しく、成膜が進行する
に従って、気化器内部で分解が加速度的に起こり、膜を
堆積するはずの成膜室では分解した配位子に起因する有
機物のみが気化して他の有機物の気化を妨げ、不均一で
安定しない原料の供給が行われていた。このため従来の
窒化タンタル膜形成用の溶液原料では、成膜速度が小さ
く、また堆積状態（as deposited）で膜中に炭素や酸素
がそれぞれ３０ａｔｍ％以上残留し、所望の窒化タンタ
ル膜を高純度で作製することが困難であった。また、こ
の形成した窒化タンタル膜の上に銅薄膜を施した場合、
窒化タンタル膜と銅との密着性が悪く、極めて剥離し易
い問題もあった。However, when a tantalum nitride film is formed by the MOCVD method using the above solution raw material, the compound contained in the raw material has poor thermal stability and decomposes inside the vaporizer as the film formation progresses. Occurs at an accelerating rate, and in the film deposition chamber where the film should be deposited, only the organic substances resulting from the decomposed ligands vaporize and prevent the vaporization of other organic substances, and non-uniform and unstable raw materials are supplied. It was Therefore, in the case of the conventional solution raw material for forming the tantalum nitride film, the film formation rate is low, and carbon and oxygen remain in the film at 30 atm% or more in the as-deposited state. It was difficult to make. Also, when a copper thin film is applied on the formed tantalum nitride film,
There is also a problem that the adhesion between the tantalum nitride film and copper is poor and peeling is extremely easy.
【０００５】本発明の目的は、均一で安定した気化が行
われ、高い成膜速度で高純度の所望のタンタル含有薄膜
が得られる有機金属化学蒸着用の溶液原料を提供するこ
とにある。本発明の別の目的は、銅薄膜の下地としてそ
のバリア性に優れた高純度のタンタル含有薄膜を提供す
ることにある。It is an object of the present invention to provide a solution raw material for metal organic chemical vapor deposition that can perform uniform and stable vaporization and can obtain a desired tantalum-containing thin film of high purity at a high film formation rate. Another object of the present invention is to provide a high-purity tantalum-containing thin film having excellent barrier properties as an underlayer of a copper thin film.
【０００６】[0006]
【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）で示されるタンタル錯体を有機溶媒に溶解
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。The invention according to claim 1 is
A solution raw material for a metal organic chemical vapor deposition method, characterized in that a tantalum complex represented by the following formula (1) is dissolved in an organic solvent.
【０００７】[0007]
【化２】
但し、Ｒはエチル基であって、Ｒ’はイソプロピル基、
ｔ-ブチル基、ｎ-ブチル基、イソブチル基、ｔ-アミル
基又はイソアミル基である。請求項１に係る溶液原料を
ＭＯＣＶＤ法により気相成長させると、均一で安定した
気化が行われ、高い成膜速度で高純度の所望のタンタル
含有薄膜が得られる。[Chemical 2] However, R is an ethyl group, R'is an isopropyl group,
a t-butyl group, an n-butyl group, an isobutyl group, a t-amyl group or an isoamyl group. When the solution raw material according to claim 1 is vapor-phase grown by MOCVD, uniform and stable vaporization is performed, and a desired high-purity tantalum-containing thin film can be obtained at a high film formation rate.
【０００８】請求項２に係る発明は、請求項１に係る発
明であって、有機溶媒が飽和炭化水素及びエステル化合
物からなる群より選ばれた１種又は２種以上の化合物で
ある溶液原料である。請求項３に係る発明は、請求項２
に係る発明であって、飽和炭化水素が、炭素数６〜１０
の直鎖状又は分岐状炭化水素である溶液原料である。請
求項４に係る発明は、請求項２又は３に係る発明であっ
て、飽和炭化水素が、ヘキサン、シクロヘキサン、n-オ
クタン、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種以上の化合物である溶液
原料である。請求項５に係る発明は、請求項２に係る発
明であって、エステル化合物が、酢酸メチル、酢酸エチ
ル、酢酸ブチル及び酢酸ペンチルからなる群より選ばれ
た１種又は２種以上の化合物である溶液原料である。The invention according to claim 2 is the invention according to claim 1, which is a solution raw material in which the organic solvent is one or more compounds selected from the group consisting of saturated hydrocarbons and ester compounds. is there. The invention according to claim 3 is the claim 2
The invention according to claim 1, wherein the saturated hydrocarbon has 6 to 10 carbon atoms.
Is a solution raw material which is a linear or branched hydrocarbon. The invention according to claim 4 is the invention according to claim 2 or 3, wherein the saturated hydrocarbon is selected from the group consisting of hexane, cyclohexane, n-octane, isooctane, n-decane and n-dodecane. It is a solution raw material which is one kind or two or more kinds of compounds. The invention according to claim 5 is the invention according to claim 2, wherein the ester compound is one or more compounds selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate and pentyl acetate. It is a solution raw material.
【０００９】請求項６に係る発明は、請求項１ないし５
いずれか記載の溶液原料を用いて有機金属化学蒸着法に
より作製されたタンタル含有薄膜である。請求項１ない
し５いずれか記載の溶液原料を用いて作製された窒化タ
ンタル薄膜は、銅薄膜の下地としてそのバリア性に優
れ、高純度である特長を有する。The invention according to claim 6 is defined by claims 1 to 5.
A tantalum-containing thin film produced by a metal organic chemical vapor deposition method using any one of the solution raw materials. The tantalum nitride thin film produced by using the solution raw material according to any one of claims 1 to 5 has an excellent barrier property as an underlayer of a copper thin film and has a characteristic of high purity.
【００１０】[0010]
【発明の実施の形態】次に本発明の実施の形態を説明す
る。本発明の溶液原料は、上記式（１）で示されるタン
タル錯体を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。このタンタル錯体と有
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。本発明
の有機溶媒は、飽和炭化水素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種以上の化合物が使用され
る。飽和炭化水素は、炭素数６〜１０の直鎖状又は分岐
状炭化水素である。具体的には、ヘキサン、シクロヘキ
サン、n-オクタン、イソオクタン、n-デカン、n-ドデカ
ンが挙げられる。また、エステル化合物は、酢酸メチ
ル、酢酸エチル、酢酸ブチル、酢酸ペンチルが挙げられ
る。BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. The solution raw material of the present invention is a solution raw material for a metal organic chemical vapor deposition method characterized in that the tantalum complex represented by the above formula (1) is dissolved in an organic solvent. The mixing ratio of the tantalum complex and the organic solvent is arbitrary, and it is preferable to appropriately prepare the compound depending on the intended use and the type of organic solvent. As the organic solvent of the present invention, one or more compounds selected from the group consisting of saturated hydrocarbons and ester compounds are used. The saturated hydrocarbon is a linear or branched hydrocarbon having 6 to 10 carbon atoms. Specific examples include hexane, cyclohexane, n-octane, isooctane, n-decane, and n-dodecane. Examples of ester compounds include methyl acetate, ethyl acetate, butyl acetate, and pentyl acetate.
【００１１】本発明のタンタル錯体は、前述した式
（１）を一般式とし、次の式（２）〜式（７）でそれぞ
れ示される錯体である。The tantalum complex of the present invention is a complex represented by the above formula (1) as a general formula and represented by the following formulas (2) to (7).
【００１２】[0012]
【化３】 [Chemical 3]
【００１３】[0013]
【化４】 [Chemical 4]
【００１４】[0014]
【化５】 [Chemical 5]
【００１５】[0015]
【化６】 [Chemical 6]
【００１６】[0016]
【化７】 [Chemical 7]
【００１７】[0017]
【化８】 [Chemical 8]
【００１８】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。成膜室１０にはニードル
バルブ３６、ガス流量調節装置３４を介してＮＨ3ガス
導入管３７が接続される。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タンタル錯体は、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、タンタル錯体の蒸気を
熱分解させ、ＮＨ3ガス導入管３７より成膜室１０内に
導入されるＮＨ3ガスと反応させることにより、生成し
た窒化タンタルを加熱された基板１３上に堆積させて窒
化タンタル薄膜を形成する。In the present embodiment, the MOCVD method uses a solution vaporization CVD method in which each solution is supplied to a heated vaporizer, each solution raw material is instantly vaporized therein, and the vaporized material is sent to a film forming chamber. As shown in FIG. 1, the MOCVD apparatus includes a film forming chamber 10
And a steam 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. An NH 3 gas introducing pipe 37 is connected to the film forming chamber 10 via a needle valve 36 and a gas flow rate adjusting device 34. The steam generator 11 includes a raw material container 18, and the raw material container 18 stores a solution raw material.
A carrier gas introduction pipe 21 is connected to the raw material container 18 via 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.
Is connected to the vaporizer 26. A carrier gas introducing pipe 29 is connected to the vaporizer 26 via a needle valve 31 and a gas flow rate adjusting 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. It is conveyed to the container 26. The tantalum complex vaporized in the vaporizer 26 to become vapor is further supplied into the film forming chamber 10 via the pipe 27 by the carrier gas introduced from the carrier gas introduction pipe 28 into the vaporizer 26. In the film forming chamber 10, the vapor of the tantalum complex is thermally decomposed and reacted with the NH 3 gas introduced into the film forming chamber 10 through the NH 3 gas introducing pipe 37, whereby the generated tantalum nitride substrate is heated. Deposit on 13 to form tantalum nitride thin film.
【００１９】本発明の溶液原料を用いて作製された窒化
タンタル薄膜は、銅薄膜の下地としてそのバリア性に優
れ、高純度である特長を有する。この窒化タンタル薄膜
は、例えばシリコン基板表面のＳｉＯ2膜上にＭＯＣＶ
Ｄ法により形成され、この窒化タンタル薄膜の上に銅薄
膜が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。The tantalum nitride thin film produced by using the solution raw material of the present invention is excellent in its barrier property as an underlayer of a copper thin film and has the features of high purity. This tantalum nitride thin film is formed on a SiO 2 film on the surface of a silicon substrate by MOCV
It is formed by the D method, and a copper thin film is formed on this tantalum nitride thin film by the MOCVD method. The type of the substrate of the present invention is not particularly limited.
【００２０】[0020]
【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＞タンタル錯体として上記式（２）に示され
る錯体（以下、ＴＡＥＰ錯体という。）を用意し、この
ＴＡＥＰ錯体の濃度が０．１モル濃度となるように有機
溶媒であるｎ-オクタンに溶解してＭＯＣＶＤ法用溶液
原料を調製した。
＜実施例２＞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３＞有機溶媒をｎ-ヘキサ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。EXAMPLES Next, examples of the present invention will be described in detail together with comparative examples. <Example 1> A complex represented by the above formula (2) (hereinafter referred to as TAEP complex) was prepared as a tantalum complex, and n- which was an organic solvent so that the concentration of this TAEP complex was 0.1 molar. It was dissolved in octane to prepare a solution raw material for the MOCVD method. Example 2 A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was isooctane. <Example 3> A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that n-hexane was used as the organic solvent.
【００２１】＜実施例４＞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５＞有機溶媒を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。
＜実施例６＞有機溶媒をシクロヘキサンにした以外は実
施例１と同様にしてＭＯＣＶＤ用溶液原料を調製した。Example 4 A MOCVD solution raw material was prepared in the same manner as in Example 1 except that n-decane was used as the organic solvent. <Example 5> Example 1 except that the organic solvent was dodecane
A solution raw material for MOCVD was prepared in the same manner as. <Example 6> A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that cyclohexane was used as the organic solvent.
【００２２】＜実施例７＞有機溶媒を酢酸ブチルにした
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８＞有機溶媒を酢酸エ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９＞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１０＞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。Example 7 A MOCVD solution raw material was prepared in the same manner as in Example 1 except that butyl acetate was used as the organic solvent. Example 8 A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was ethyl acetate. <Example 9> A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was methyl acetate. <Example 10> A solution raw material for MOCVD was prepared in the same manner as in Example 1 except that the organic solvent was pentyl acetate.
【００２３】＜実施例１１〜２０＞タンタル錯体を式
（３）に示される錯体（以下、ＴＡＥＢ錯体という。）
にした以外は実施例１〜１０と同様にしてＭＯＣＶＤ用
溶液原料をそれぞれ調製した。
＜実施例２１〜３０＞タンタル錯体を式（４）に示され
る錯体（以下、ＴＡＥｎＢ錯体という。）にした以外は
実施例１〜１０と同様にしてＭＯＣＶＤ用溶液原料をそ
れぞれ調製した。
＜実施例３１〜４０＞タンタル錯体を式（５）に示され
る錯体（以下、ＴＡＥｉＢ錯体という。）にした以外は
実施例１〜１０と同様にしてＭＯＣＶＤ用溶液原料をそ
れぞれ調製した。
＜実施例４１〜５０＞タンタル錯体を式（６）に示され
る錯体（以下、ＴＡＥｔＡｍ錯体という。）にした以外
は実施例１〜１０と同様にしてＭＯＣＶＤ用溶液原料を
それぞれ調製した。
＜実施例５１〜６０＞タンタル錯体を式（７）に示され
る錯体（以下、ＴＡＥｉＡｍ錯体という。）にした以外
は実施例１〜１０と同様にしてＭＯＣＶＤ用溶液原料を
それぞれ調製した。<Examples 11 to 20> The tantalum complex is a complex represented by the formula (3) (hereinafter referred to as TAEB complex).
Solution raw materials for MOCVD were prepared in the same manner as in Examples 1 to 10 except that the above was used. <Examples 21 to 30> Solution raw materials for MOCVD were prepared in the same manner as in Examples 1 to 10 except that the tantalum complex was changed to the complex represented by the formula (4) (hereinafter referred to as TAEnB complex). <Examples 31 to 40> MOCVD solution raw materials were prepared in the same manner as in Examples 1 to 10, except that the tantalum complex was changed to the complex represented by the formula (5) (hereinafter referred to as TAEiB complex). <Examples 41 to 50> Solution raw materials for MOCVD were prepared in the same manner as in Examples 1 to 10 except that the tantalum complex was changed to the complex represented by the formula (6) (hereinafter referred to as TAEtAm complex). <Examples 51 to 60> MOCVD solution raw materials were prepared in the same manner as in Examples 1 to 10, except that the tantalum complex was changed to the complex represented by the formula (7) (hereinafter referred to as TAEiAm complex).
【００２４】＜比較例１〜１０＞タンタル錯体をＰＤＭ
ＡＴ錯体にした以外は実施例１〜１０と同様にしてＭＯ
ＣＶＤ用溶液原料をそれぞれ調製した。
＜比較例１１〜２０＞タンタル錯体をＰＤＥＡＴ錯体に
した以外は実施例１〜１０と同様にしてＭＯＣＶＤ用溶
液原料を調製した。<Comparative Examples 1 to 10> A tantalum complex was added to PDM.
MO in the same manner as in Examples 1 to 10 except that an AT complex was used.
Each of the solution raw materials for CVD was prepared. <Comparative Examples 11 to 20> MOCVD solution raw materials were prepared in the same manner as in Examples 1 to 10 except that the tantalum complex was changed to the PDEAT complex.
【００２５】＜比較試験＞実施例１〜６０及び比較例１
〜２０で得られた溶液原料をそれぞれ５種類用意した。
基板として、基板表面にＳｉＯ2膜（厚さ５０００Å）
が熱酸化により形成され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４５０℃とした。気化温度を７０℃、圧
力を２Ｔｏｒｒ即ち約２６６Ｐａ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１００
ｃｃｍとした。また反応ガスとしてＮＨ3ガスを用い、
その流量を１００ｃｃｍとした。溶液原料を０．０１ｃ
ｃ／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タンタル含有薄膜である窒化タ
ンタル薄膜について以下に示す試験を行った。<Comparative Test> Examples 1 to 60 and Comparative Example 1
Five kinds of the solution raw materials obtained in each step were prepared.
As substrate, SiO 2 film (thickness 5000Å) on substrate surface
A silicon substrate formed by thermal oxidation was prepared. The prepared substrate was placed in the film forming chamber of the MOCVD apparatus shown in FIG. 1, and the substrate temperature was 450 ° C. The vaporization temperature was 70 ° C. and the pressure was 2 Torr, that is, about 266 Pa.
Ar gas was used as the carrier gas and its flow rate was 100
It was set to ccm. Further, NH 3 gas is used as a reaction gas,
The flow rate was 100 ccm. 0.01c of solution raw material
A tantalum nitride thin film which is a thin film containing tantalum formed on a substrate by supplying at a rate of c / min and taking out from the film forming chamber for each one at 1, 5, 10, 20 and 30 minutes. The following test was performed on the.
【００２６】 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。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.
【００２７】 剥離試験
各成膜時間で取り出した窒化タンタル薄膜の上に銅薄膜
をスパッタリング法により成膜し、この銅薄膜を形成し
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。Peeling Test A copper thin film was formed on the tantalum nitride thin film taken out at each film forming time by a sputtering method, and a peeling test (JIS K 5600-5-) was performed on the substrate on which the copper thin film was formed.
6) was performed. Specifically, first, a lattice pattern was formed on the substrate by making 6 incisions in the copper thin film on the substrate so as to penetrate the film at equal intervals in the vertical and horizontal directions. Then brushed back and forth with a soft brush along both diagonals of the formed grid pattern.
【００２８】 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、２Ｔｏｒｒ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、
２Ｔｏｒｒの１．６０倍の圧力が気化器内で生じている
ことを表す。Thermal Stability Evaluation Test The following test was conducted using the test apparatus shown in FIG. The apparatus shown in FIG. 2 has a structure in which the film forming chamber of the MOCVD apparatus shown in FIG. 1 is removed. First, the solution raw material is conveyed to the vaporizer 26 heated to 70 ° C. at room temperature, heated to 70 ° C. under a reduced pressure of 2 Torr to vaporize the solution raw material, and then the cold side provided on the pump side below the vaporizer 26. The compound after vaporization was captured by the trap 15. The trap recovery rate was calculated from the trapped amount of the raw material charged into the apparatus.
Further, the pressure sensor measured the pressure rise inside the vaporizer. For example, if the value in the table is 60% occlusion,
This means that a pressure of 1.60 times 2 Torr is generated in the vaporizer.
【００２９】実施例１〜６０及び比較例１〜２０で得ら
れた溶液原料を用いた試験結果を表１〜表１０にそれぞ
れ示す。The test results using the solution raw materials obtained in Examples 1 to 60 and Comparative Examples 1 to 20 are shown in Tables 1 to 10, respectively.
【００３０】[0030]
【表１】 [Table 1]
【００３１】[0031]
【表２】 [Table 2]
【００３２】[0032]
【表３】 [Table 3]
【００３３】[0033]
【表４】 [Table 4]
【００３４】[0034]
【表５】 [Table 5]
【００３５】[0035]
【表６】 [Table 6]
【００３６】[0036]
【表７】 [Table 7]
【００３７】[0037]
【表８】 [Table 8]
【００３８】[0038]
【表９】 [Table 9]
【００３９】[0039]
【表１０】 [Table 10]
【００４０】表８〜表１０より明らかなように、比較例
１〜２０の溶液原料を用いて成膜されたタンタル含有薄
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。これに対して表１〜表８より明らかなように、
実施例１〜６０の溶液原料を用いて作製されたタンタル
含有薄膜は、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、銅薄膜が剥離する割合が低く、非常に密着性が高い
ことが判る。熱安定性評価試験では、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。As is clear from Tables 8 to 10, the tantalum-containing thin films formed by using the solution raw materials of Comparative Examples 1 to 20 have variations in the film thickness per film forming time, and the film forming reproducibility is poor. It turns out to be bad. In addition, the film formation rate is also very slow. Moreover, in the adhesion evaluation test, the copper thin film was peeled from the substrate surface in most of the samples. In the thermal stability evaluation test, the trap recovery rate is low, and it is considered that most of the trap adhered to the inside of the device. Further, the pressure rise value inside the vaporizer also rises as the film forming time becomes longer, and it is considered that the decomposition product adhered to the inside of the vaporizer and the inside of the pipe to raise the pressure. On the other hand, as is clear from Tables 1 to 8,
It can be seen that the tantalum-containing thin films produced using the solution raw materials of Examples 1 to 60 have a large film thickness as the film forming time advances, and thus the film forming stability is high. In the adhesion evaluation test, it is found that the rate of peeling of the copper thin film is low and the adhesion is very high. In the thermal stability evaluation test, a high trap recovery rate is shown, and the pressure rise value inside the carburetor is about 1% and there is almost no risk of blockage.
【００４１】[0041]
【発明の効果】以上述べたように、上記式（１）に示す
タンタル錯体を有機溶媒、飽和炭化水素及びエステル化
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
に溶解した本発明のＭＯＣＶＤ用溶液原料は、銅薄膜の
下地としてそのバリア性に優れ、高純度である特長を有
する。本発明の溶液原料を用いてＳｉＯ2膜上にタンタ
ル含有薄膜を気相成長させる際、高い成膜速度で安定な
成膜が可能となる。得られたタンタル含有薄膜上へ銅薄
膜を作製する際に、成膜法を問わず、密着性に優れた銅
薄膜が作製可能となる。As described above, the present invention in which the tantalum complex represented by the above formula (1) is dissolved in one or more compounds selected from the group consisting of an organic solvent, a saturated hydrocarbon and an ester compound. The MOCVD solution raw material is excellent in its barrier property as an underlayer of a copper thin film and has a feature of high purity. When vapor-depositing a tantalum-containing thin film on a SiO 2 film using the solution raw material of the present invention, stable film formation is possible at a high film formation rate. When a copper thin film is formed on the obtained tantalum-containing thin film, a copper thin film having excellent adhesion can be formed regardless of the film forming method.
【図１】ＭＯＣＶＤ装置の概略図。FIG. 1 is a schematic diagram of a MOCVD apparatus.
【図２】本発明の実施例に使用される装置を示す概略
図。FIG. 2 is a schematic diagram showing an apparatus used in an embodiment of the present invention.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 小木 勝実 茨城県那珂郡那珂町向山1002番地14 三菱 マテリアル株式会社総合研究所那珂研究セ ンター内 Ｆターム(参考） 4H006 AA03 AB99 4H050 AA03 AB99 WB14 WB21 4K030 AA11 AA13 BA17 BA38 CA04 CA11 FA10 4M104 BB04 BB32 DD37 DD44 DD45 HH05 HH08 HH20 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Katsumi Ogi 1002 Mukayama, Naka-machi, Naka-machi, Naka-gun, Ibaraki Prefecture 14 Mitsubishi Materials Research Laboratories Naka Research Center In the center F-term (reference) 4H006 AA03 AB99 4H050 AA03 AB99 WB14 WB21 4K030 AA11 AA13 BA17 BA38 CA04 CA11 FA10 4M104 BB04 BB32 DD37 DD44 DD45 HH05 HH08 HH20
Claims (6)
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。 【化１】 但し、Ｒはエチル基であって、Ｒ’はイソプロピル基、
ｔ-ブチル基、ｎ-ブチル基、イソブチル基、ｔ-アミル
基又はイソアミル基である。1. A solution raw material for a metal organic chemical vapor deposition method, characterized in that a tantalum complex represented by the following formula (1) is dissolved in an organic solvent. [Chemical 1] However, R is an ethyl group, R'is an isopropyl group,
a t-butyl group, an n-butyl group, an isobutyl group, a t-amyl group or an isoamyl group.
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
である請求項１記載の溶液原料。2. The solution raw material according to claim 1, wherein the organic solvent is one or more compounds selected from the group consisting of saturated hydrocarbons and ester compounds.
状又は分岐状炭化水素である請求項２記載の溶液原料。3. The solution raw material according to claim 2, wherein the saturated hydrocarbon is a linear or branched hydrocarbon having 6 to 10 carbon atoms.
サン、n-オクタン、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
である請求項２又は３記載の溶液原料。4. The saturated hydrocarbon is one or two or more compounds selected from the group consisting of hexane, cyclohexane, n-octane, isooctane, n-decane and n-dodecane. Solution raw material.
チル、酢酸ブチル及び酢酸ペンチルからなる群より選ば
れた１種又は２種以上の化合物である請求項２記載の溶
液原料。5. The solution raw material according to claim 2, wherein the ester compound is one or more compounds selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate and pentyl acetate.
料を用いて有機金属化学蒸着法により作製されたタンタ
ル含有薄膜。6. A tantalum-containing thin film produced by a metal organic chemical vapor deposition method using the solution raw material according to claim 1.
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| KR101912127B1 (en) | 2011-05-27 | 2018-10-26 | 가부시키가이샤 아데카 | Method for manufacturing molybdenum oxide-containing thin film, starting material for forming molybdenum oxide-containing thin film, and molybdenum amide compound |
| JPWO2014077073A1 (en) * | 2012-11-19 | 2017-01-05 | 株式会社Adeka | Manufacturing method of thin film containing molybdenum, raw material for forming thin film, and molybdenum imide compound |
| WO2014077073A1 (en) * | 2012-11-19 | 2014-05-22 | 株式会社Adeka | Method for producing thin film containing molybdenum, thin film-forming starting material, and molybdenum imide compound |
| US9988411B2 (en) | 2012-11-19 | 2018-06-05 | Adeka Corporation | Thin-film-forming material including a molybdenum imide compound |
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| US10150789B2 (en) | 2012-11-19 | 2018-12-11 | Adeka Corporation | Molybdenum imide compound |
| CN114269762A (en) * | 2019-06-05 | 2022-04-01 | 弗萨姆材料美国有限责任公司 | Novel group V and group VI transition metal precursors for thin film deposition |
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