JP3623848B2

JP3623848B2 - Evaporation source for organic compounds and vapor deposition polymerization apparatus using the same

Info

Publication number: JP3623848B2
Application number: JP11024896A
Authority: JP
Inventors: 正行飯島; 洋幸山川
Original assignee: Ulvac Inc
Current assignee: Ulvac Inc
Priority date: 1996-04-05
Filing date: 1996-04-05
Publication date: 2005-02-23
Anticipated expiration: 2016-04-05
Also published as: JPH09272703A

Description

【０００１】
【発明の属する技術分野】
本発明は、有機化合物モノマーを蒸発させて重合を行う蒸着重合によってポリイミド、ポリ尿素等の高分子薄膜を形成する際に用いる有機化合物用蒸発源及びこれを用いた蒸着重合装置に関する。
【０００２】
【従来の技術】
近年、真空中で有機化合物の有機化合物モノマーを蒸発させてこれを基体上で重合させることによって高分子薄膜を形成する蒸着重合法が提案されている。
図５は、従来の蒸着重合装置の一例を示すものである。
図５に示すように、この蒸着重合装置１０１は、気密状態を保持可能な処理室１０２を有し、この処理室１０２は、図示しない外部の真空ポンプその他の真空排気系に接続されている。そして、処理室１０２内の上部には、高分子薄膜を形成すべき基板１０３が基板ホルダ１０４によって下向きに保持され、また、基板ホルダ１０４の背面側には、基板１０３を所望の温度に加熱するためのヒーター１０５が設けられている。
【０００３】
一方、処理室１０２の下方には、基板１０３に対抗するように、各有機化合物モノマーａ、ｂを蒸発させるための蒸発源が設けられる。すなわち、例えばガラスからなる蒸発用容器１０６、１０７が設けられるとともに、各蒸発用容器１０６、１０７の近傍に、加熱用のヒーター１０８、１０９と温度センサ１１０、１１１が設けられ、これらによって有機化合物モノマーａ、ｂの蒸発レートが常に一定に保たれるように構成される。
【０００４】
なお、蒸発用容器１０６、１０７の間には、各有機化合物モノマーａ、ｂの蒸気の混合を防止するための仕切板１１２が設けられ、また、加熱用のヒーター１０８、１０９の上方には、有機化合物モノマーａ、ｂの蒸気の混入を防止するためのシャッター１１３が設けられている。
【０００５】
図６に示すように、本出願人は、先に、この種の蒸発源１２０として、有機化合物のモノマーａを収容したガラス製容器１２１と、このガラス製容器１２１を輻射加熱するハロゲンランプ又は金属抵抗体の加熱装置１２２と、ガラス製容器１２１の壁面１２１ｂに接触させた温調用熱電対１２３と、このガラス製容器１２１内の有機化合物モノマーａ中に挿入したモニター用熱電対１２４とを備え、精度の高い有機化合物モノマーａの温度制御を行う蒸発源を提案した（特開平６−８１１２９号公報参照）。
【０００６】
また、本出願人は、有機化合物モノマーの使用効率を向上させるため、蒸発源から基板に至る間の真空処理室内の壁面を加熱する装置も提案した（特開平４−４５２５９号公報参照）。
【０００７】
【発明が解決しようとする課題】
しかしながら、このような従来の蒸発源においては、次のような問題があった。
すなわち、上述した第１の従来例の場合、有機化合物モノマーａを収容したガラス製容器１２１と基板１０３との間が離間しているため、有機化合物モノマーａ、ｂの蒸気のうち基板１０３に到達しないものがあり、その結果、基板１０３上に形成される高分子薄膜の厚みを均一にすることが困難であるという問題があった。
【０００８】
一方、第２の従来例の場合によれば、蒸発源から蒸発した有機化合物モノマーａ、ｂのほとんどが基板１０３に到達するものの、それでも基板１０３の中心ほど膜厚が厚くなり、膜厚の均一な高分子薄膜を得ることが困難であるという問題があった。
【０００９】
本発明は、このような従来の技術の課題を解決するためになされたもので、有機化合物モノマーの使用効率が高く、しかも基体において均一な膜厚の高分子薄膜を形成しうる有機化合物用蒸発源及びこれを用いた蒸着重合装置を提供することを目的とするものである。
【００１０】
【課題を解決するための手段】
上記目的を達成するため、請求項１記載の発明は、真空処理室内で二つの蒸発用容器内に収容した異なる有機化合物モノマーを加熱してこれを蒸発させる有機化合物用蒸発源において、前記二つの蒸発用容器の開口部から流出する有機化合物モノマーの蒸気を周囲に飛散させることなく混合して前記基体に導くための筒状部材を有する蒸発制御槽を設け、前記筒状部材の一方の開口部が前記蒸発用容器の開口部を囲むとともに、当該蒸発用容器の開口部が前記筒状部材の内部に入り込むように構成したことを特徴とする有機化合物用蒸発源である。
この場合、請求項２記載の発明のように、請求項１記載の発明において、二つの蒸発用容器の間に有機化合物モノマーを下方へ逃がさないようにするための遮蔽板を設けたることも効果的である。
また、請求項３記載の発明のように、請求項１又は２のいずれか１項記載の発明において、筒状部材内に膜厚分布補正用の発熱体を設けることも効果的である。
さらに、請求項４記載の発明のように、請求項３記載の発明において、膜厚分布補正用の発熱体として、周囲からの熱伝導によって加熱される部材からなるものを用いることも効果的である。
さらにまた、請求項５記載の発明のように、請求項１乃至４のいずれか１項記載の発明において、膜厚分布補正用の発熱体が、当該基体の中心部に対応する位置に、当該基体と平行となるように配置されることも効果的である。
一方、請求項６記載の発明は、真空処理室内に請求項１乃至５のいずれか１項記載の有機化合物用蒸発源を備えたことを特徴とする蒸着重合装置である。
【００１１】
かかる構成を有する請求項１記載の発明の場合、二つの蒸発用容器の開口部から流出する有機化合物モノマーの蒸気が蒸発制御槽内の壁面によって反射され、その結果、これら有機化合物モノマーの蒸気の混合が促進される。そして、その状態で有機化合物モノマーの蒸気を基体に導びけば、均一な状態で有機化合物モノマーの蒸気が基体に到達し、基体上に堆積するようになる。
また、本発明においては、蒸発制御槽の筒状部材の一方の開口部が蒸発用容器の開口部を囲むとともに、当該蒸発用容器の開口部が筒状部材の内部に入り込むように構成し、二つの蒸発用容器の開口部から流出する有機化合物モノマーの蒸気が周囲に飛散することなく直接筒状部材内に導入するようにしたことから、混合有機化合物モノマーの使用効率を向上させることが可能になる。
この場合、請求項２記載の発明のように、二つの蒸発用容器の間に有機化合物モノマーを下方へ逃がさないようにするための遮蔽板を設ければ、さらに有機化合物モノマーの使用効率を高めることが可能になる。
さらに、請求項３記載の発明のように、筒状部材内に膜厚分布補正用の発熱体を設ければ、有機化合物モノマーの混合が一層促進される。
この場合、請求項４記載の発明のように、膜厚分布補正用の発熱体として、周囲からの熱伝導によって加熱されるものを用いれば、発熱体を加熱する手段を特に設ける必要がない。
さらにまた、請求項５記載の発明のように、膜厚分布補正用の発熱体が、当該基体の中心部に対応する位置に、当該基体と平行となるように配置すれば、より膜厚の均一性を高めることが可能になる。
一方、請求項６記載の発明のように、真空処理室内に請求項１乃至５のいずれか１項記載の有機化合物用蒸発源を備えれば、有機化合物モノマーの使用効率が高く、しかも基体上における高分子薄膜の膜厚分布が均一にしうる蒸着重合装置が容易に得られる。
【００１２】
【発明の実施の形態】
以下、本発明に係る有機化合物用蒸発源及びこれを用いた真空処理装置の実施の形態を図面を参照して詳細に説明する。
【００１３】
図１は、本発明が適用される蒸着重合装置の好ましい一実施の形態を示すものである。
図１に示すように、この蒸着重合装置１は、気密状態を保持可能な処理室２を有し、この処理室２は、図示しない外部の真空ポンプその他の真空排気系に接続されている。そして、処理室２内の上部には、高分子薄膜を形成すべき基体としての基板３が基板ホルダ４によって下向きに保持され、また、基板ホルダ４の背面側には、基板３を所望の温度に加熱するためのヒーター５が設けられている。ここで、基板３としては、シリコンウエハ、ガラス基板、金属板、プラスチック基板等が用いられる。
【００１４】
一方、処理室２の下方には、各有機化合物モノマーＡ、Ｂを蒸発させるための蒸発源６が設けられる。本実施の形態においては、例えばガラスからなる蒸発用容器７、８が設けられるとともに、各蒸発用容器７、８の内部に、加熱用のヒーター９、１０が設けられる。なお、各蒸発用容器７、８の内部には、上述の第１の従来例と同様の熱電対が設けられ、これらによって有機化合物モノマーＡ、Ｂの温度ひいては蒸発レートが常に一定に保たれるように構成される。
【００１５】
図１に示すように、本実施の形態においては、各蒸発用容器７、８の上方に蒸発制御槽６Ａが設けられている。この蒸発制御槽６Ａは、筒状部材である円筒部材１１と、シャッター１３とから構成される。
【００１６】
円筒部材１１は、例えばステンレス等の金属からなり、その一方の開口部が各蒸発用容器７、８の開口部７ａ、８ａを囲むとともに、他方の開口部が基板３に対向するように配置される。そして、円筒部材１１の基板３に対向する側の開口部がシャッター１３により必要に応じて開閉されるように構成される。
【００１７】
一方、図１に示すように、各蒸発用容器７、８の開口部７ａ、８ａから流出する有機化合物モノマーＡ、Ｂの蒸気を周囲に飛散させることなく混合して基板３に導くため、各蒸発用容器７、８の開口部７ａ、８ａが円筒部材１１の内部に入り込むように構成される。また、円筒部材１１の周囲には、図示しない電源に接続された加熱用のヒーター１２が巻き付けられている。さらに、蒸発用容器７、８の間には、各有機化合物モノマーＡ、Ｂを下方へ逃がさないようにするための遮蔽板１５が設けられている。
【００１８】
このような構成において、基板３上に高分子薄膜を形成する場合には、処理室２内の真空度を調整し、シャッター１３を閉じた状態で各有機化合物モノマーＡ、Ｂを所定の温度に保つように加熱する。しかる後、各蒸発用容器７、８の蒸発口７ａ、８ａから蒸気が発生し、蒸発制御槽６Ａの内部に各有機化合物モノマーＡ、Ｂの蒸気が導入される。一方、円筒部材１１に巻かれたヒーター１２によって円筒部材１１を加熱し、有機化合物モノマーＡ、Ｂの蒸気を所定の温度に保持する。
【００１９】
次いで、各有機化合物モノマーＡ、Ｂが所定の温度に達して所要の蒸発量が得られた後に、シャッター１３を開き、所定の析出速度で基板３上に有機化合物の薄膜を蒸着し、堆積させた後にシャッター１３を閉じ、基板３上で重合反応を起こさせて高分子薄膜を形成する。
【００２０】
かかる構成を有する本実施の形態においては、各蒸発用容器７、８の開口部７ａ、８ａから流出する各有機化合物モノマーＡ、Ｂの蒸気が、蒸発制御槽６Ａ内に一時的に収容される際に円筒部材１１の内壁面によって反射され、その結果、有機化合物モノマーＡ、Ｂの蒸気の混合が促進される。そして、その状態で有機化合物モノマーＡ、Ｂの蒸気を基板３に導びけば、均一な状態で有機化合物モノマーＡ、Ｂの蒸気が基体に到達するため、基板３上において均一な高分子薄膜が形成される。
【００２１】
また、円筒部材１１の周囲には加熱用のヒーター１２が設けられていることから、蒸発用容器７、８から蒸発した各有機化合物モノマーＡ、Ｂの蒸気のほとんどが基板３に到達し、その結果、各有機化合物モノマーＡ、Ｂの使用効率を高いレベルに維持することができる。
【００２２】
このように、本実施の形態によれば、有機化合物モノマーＡ、Ｂの使用効率が高く、しかも基板３上における高分子薄膜の膜厚分布を均一にしうる真空処理装置が容易に得られる。
【００２３】
図２は、本発明が適用される蒸着重合装置の他の実施の形態を示すものである。以下、上記実施の形態と対応する部分について同一の符号を付して説明する。
図２に示すように、本実施の形態に係る蒸着重合装置１Ａにおいては、蒸発制御槽６Ａの内部であってシャッター１３の近傍に膜厚分布補正用の発熱体１４が設けられている。この発熱体１４は、例えばステンレス等の金属製の材料からなり、円盤形状を有している。この発熱体１４は、例えば、基板３の中心部に対応する位置に、基板３と平行となるように水平方向に配置される。
【００２４】
かかる構成を有する本実施の形態によれば、処理室２内の温度上昇に伴って発熱体１４の温度も上昇し、発熱体１４の近傍において蒸気の対流が生じるので、蒸発制御槽６Ａ内における各有機化合物モノマーＡ、Ｂの混合が一層促進される。その結果、基板３上においてより均一な高分子薄膜を形成することができる。
【００２５】
この場合、発熱体１４は周囲からの熱伝導によって加熱されるので、発熱体１４を加熱する手段を特に設ける必要がなく、簡素な構成の蒸着重合装置１Ａを得ることができる。その他の構成及び作用効果については、上述の実施の形態と同様であるのでその詳細な説明を省略する。
【００２６】
なお、本発明は上述の実施の形態に限られることなく、種々の変更を行うことができる。
例えば、筒状部材、発熱体の材料としては種々のものを用いることができる。ただし、熱伝導率の高いステンレス等の金属を用いるとより効果的である。
【００２７】
また、筒状部材の形状、大きさについては、基体に有機化合物モノマーの蒸気を導くことができる限り、種々のものを用いることができる。ただし、高分子薄膜を形成すべき基体の形状、大きさに対応するような例えば円筒形状のものを用いれば、より効果的である。
【００２８】
一方、発熱体の形状についても、円盤形状に限られず、種々のものとすることができるが、円盤状のものを用いれば、水平方向に対する膜厚の均一化に有利となるというメリットがある。
【００２９】
【実施例】
以下、本発明に係る蒸発源及びこれを用いた蒸着重合装置の実施例を比較例とともに詳細に説明する。
【００３０】
〔実施例１〕
図１に示す蒸発源及び蒸着重合装置を用い、基板３上にポリ尿素膜を形成した。
この場合、基板３としては、一辺が１２０ｍｍの正方形状のガラス板又は直径が５インチ（１２．７ｍｍ）のＳｉウェハを用いた。また、円筒部材１１としては、外径１００ｍｍ、高さ２２０ｍｍのステンレス製のものを用い、その周壁をヒーター１２によって１００℃に加熱した。そして、蒸発用容器７に有機化合物モノマーＡとして４、４'−ジフェニルメタンジイソシアナート（ＭＤＩ）を５０ｃｍ³注入して７８℃に加熱するとともに、蒸発用容器８に有機化合物モノマーＢとして４、４'−ジアミノジフェニルメタン（ＭＤＡ）を５０ｃｍ³注入して１０９℃に加熱した。
【００３１】
なお、各蒸発用容器７、８の開口部７ａ、８ａの内径は２０ｍｍとし、開口部７ａ、８ａ同士の間隔は２０ｍｍとした。また、各蒸発用容器７、８の開口部７ａ、８ａと基板３との間隔を３００ｍｍとし、シャッター１３と基板３との間隔を８０ｍｍとした。この装置により得られたポリ尿素膜の膜厚分布を図３に示す。
【００３２】
〔比較例〕
比較例として、従来例と同様の構成の装置、すなわち、円筒部材１１を有しない点以外、実施例１と同様の装置を用い、基板３上にポリ尿素膜を形成した。この装置により得られたポリ尿素膜の膜厚分布を図３に示す。
【００３３】
図３から理解されるように、本発明の蒸発源を用いた蒸着重合装置の場合は、従来の蒸発源を用いた蒸着重合装置に比べて膜厚分布が向上した。例えば、基板３の中心部から５０ｍｍ離れた位置において、比較例１の場合は中心部の５０％以下の膜厚しか得られなかったのに対し、実施例１の場合は中心部に比べて７３％程度の膜厚が得られ、均一な膜厚分布となった。
また、ポリ尿素膜の成膜速度についても、比較例１の場合に比べて約５倍の速度で薄膜を形成することができた。
【００３４】
〔実施例２〕
本実施例においては、図２に示す蒸着重合装置１Ａを用い、実施例１と同様の方法によって基板３上にポリ尿素膜を形成した。この場合、発熱体１４としては、直径３０ｍｍのステンレス製の円盤状の部材を用い、基板３の中央部分に対応する位置に基板３と平行になるように配置した。この蒸着重合装置１Ａにおいて有機化合物モノマーＡ、Ｂを蒸発させたところ、発熱体１４は、周囲からの熱伝導により９２℃まで上昇した。
【００３５】
図４は、実施例２の装置により得られたポリ尿素膜の膜厚分布を示すものである。図４の●を結んだプロットで示すように、本実施例の場合は、基板３の中心部から５０ｍｍ離れた位置において、中心部との膜厚の差が±４％程度となり、実施例１の装置よりも一層均一なポリ尿素膜が得られた。
【００３６】
一方、モンテカルロ法を用いたシミュレーションにより実施例２の装置における膜厚分布を算出した。すなわち、図２に示す蒸発制御槽６Ａと同じ形状の容器に一定量のモノマーのガスを導入し、ＣＯＳ則（余弦法則）によって反射し基板に入射するガスのある割合（例えば５０％）がそのまま堆積したとして、基板の所定の範囲に入射するガスの量（分布）を求めた。この場合、モノマーのガスの飛散する方向を乱数を用いて決定した。その結果を図４の○を結んだプロットで示す。
【００３７】
図４から理解されるように、計算の結果は実験値とほぼ一致し、蒸発源の形状が変わっても容易に最適な膜厚分布に制御可能な蒸発源を得ることがわかった。
【００３８】
【発明の効果】
以上述べたように、本発明に係る有機化合物用蒸発源及び蒸着重合装置によれば、有機化合物モノマーの使用効率を向上させることができ、しかも基体上において均一な膜厚の高分子薄膜を形成することができる。
【図面の簡単な説明】
【図１】本発明が適用される蒸着重合装置の一実施の形態を示す概略構成図
【図２】本発明が適用される蒸着重合装置の他の実施の形態を示す概略構成図
【図３】本発明の蒸発源と従来の蒸発源を用いた場合のポリ尿素膜の膜厚分布をそれぞれ示すグラフ
【図４】実施例２の装置により得られるポリ尿素膜の膜厚分布を示すグラフ
【図５】従来の蒸着重合装置の一例を示す概略構成図
【図６】従来の蒸発源の一例を示す概略構成図
【符号の説明】
１、１Ａ…蒸着重合装置、２…処理室、３…基板、５…ヒーター、６…蒸発源、６Ａ…蒸発制御槽、７、８…蒸発用容器、７ａ、８ａ…開口部、９、１０…ヒーター、１１…円筒部材、１２…ヒーター、１３…シャッター、１４…発熱体、１５…遮蔽板 [0001]
BACKGROUND OF THE INVENTION
The present invention relates to an evaporation source for an organic compound used when a polymer thin film such as polyimide or polyurea is formed by vapor deposition polymerization in which an organic compound monomer is evaporated to perform polymerization, and a vapor deposition polymerization apparatus using the same.
[0002]
[Prior art]
In recent years, a vapor deposition polymerization method has been proposed in which a polymer thin film is formed by evaporating an organic compound monomer of an organic compound in a vacuum and polymerizing it on a substrate.
FIG. 5 shows an example of a conventional vapor deposition polymerization apparatus.
As shown in FIG. 5, this vapor deposition polymerization apparatus 101 has a processing chamber 102 capable of maintaining an airtight state, and this processing chamber 102 is connected to an external vacuum pump (not shown) or other vacuum exhaust system. A substrate 103 on which a polymer thin film is to be formed is held downward by the substrate holder 104 in the upper part of the processing chamber 102, and the substrate 103 is heated to a desired temperature on the back side of the substrate holder 104. A heater 105 is provided.
[0003]
On the other hand, an evaporation source for evaporating the organic compound monomers a and b is provided below the processing chamber 102 so as to oppose the substrate 103. That is, for example, evaporation containers 106 and 107 made of glass are provided, and heaters 108 and 109 and temperature sensors 110 and 111 for heating are provided in the vicinity of each of the evaporation containers 106 and 107, and these are used as the organic compound monomer. It is configured so that the evaporation rates of a and b are always kept constant.
[0004]
A partition plate 112 is provided between the evaporation containers 106 and 107 to prevent mixing of the vapors of the organic compound monomers a and b, and above the heaters 108 and 109 for heating, A shutter 113 is provided for preventing vapor mixture of the organic compound monomers a and b.
[0005]
As shown in FIG. 6, the applicant of the present invention firstly, as this type of evaporation source 120, a glass container 121 containing a monomer a of an organic compound, and a halogen lamp or metal that radiates and heats the glass container 121. A resistor heating device 122, a temperature-control thermocouple 123 brought into contact with the wall surface 121b of the glass container 121, and a monitor thermocouple 124 inserted into the organic compound monomer a in the glass container 121, An evaporation source for controlling the temperature of the organic compound monomer a with high accuracy has been proposed (see JP-A-6-81129).
[0006]
The present applicant has also proposed an apparatus for heating the wall surface of the vacuum processing chamber between the evaporation source and the substrate in order to improve the use efficiency of the organic compound monomer (see JP-A-4-45259).
[0007]
[Problems to be solved by the invention]
However, such a conventional evaporation source has the following problems.
That is, in the case of the first conventional example described above, since the glass container 121 containing the organic compound monomer a and the substrate 103 are separated from each other, the vapor reaches the substrate 103 among the vapors of the organic compound monomers a and b. As a result, there is a problem that it is difficult to make the thickness of the polymer thin film formed on the substrate 103 uniform.
[0008]
On the other hand, according to the second conventional example, although most of the organic compound monomers a and b evaporated from the evaporation source reach the substrate 103, the film thickness becomes thicker toward the center of the substrate 103, and the film thickness is uniform. There was a problem that it was difficult to obtain a simple polymer thin film.
[0009]
The present invention has been made in order to solve the above-described problems of the prior art, and is an evaporation method for organic compounds capable of forming a polymer thin film having a uniform film thickness on a substrate with high use efficiency of organic compound monomers. It is an object of the present invention to provide a source and a vapor deposition polymerization apparatus using the same.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the invention described in claim 1 is directed to an organic compound evaporation source that heats and vaporizes different organic compound monomers contained in two evaporation containers in a vacuum processing chamber . Provided with an evaporation control tank having a cylindrical member for mixing and guiding the vapor of the organic compound monomer flowing out from the opening of the evaporation container to the substrate without scattering to the surroundings, one opening of the cylindrical member Is an evaporation source for an organic compound, wherein the evaporation source surrounds the opening of the evaporation container and the opening of the evaporation container enters the inside of the cylindrical member .
In this case, as in the invention of claim 2, wherein, in the invention according to the first aspect, even Rukoto provided with shielding plates for preventing escape of organic compound monomer downward between two evaporation vessel It is effective.
In addition, as in the invention described in claim 3, in the invention described in claim 1 or 2 , it is also effective to provide a heating element for correcting the film thickness distribution in the cylindrical member.
Furthermore, as in the invention described in claim 4, in the invention described in claim 3, it is also effective to use a member made of a member heated by heat conduction from the surroundings as a heating element for correcting the film thickness distribution. is there.
Furthermore, as in the invention according to claim 5, in the invention according to any one of claims 1 to 4, the heating element for correcting the film thickness distribution is located at a position corresponding to the central portion of the substrate. It is also effective to arrange it so as to be parallel to the substrate .
On the other hand, an invention according to claim 6 is a vapor deposition polymerization apparatus comprising the evaporation source for an organic compound according to any one of claims 1 to 5 in a vacuum processing chamber.
[0011]
For the invention of claim 1, wherein having such a configuration, the vapor of the organic compound monomer flowing from the opening of the two evaporation vessel is reflected by the wall of the evaporation control chamber, as a result, the vapor of the organic compound monomer Mixing is promoted. If the vapor of the organic compound monomer is guided to the substrate in this state, the vapor of the organic compound monomer reaches the substrate in a uniform state and is deposited on the substrate.
Further, in the present invention, one opening of the cylindrical member of the evaporation control tank surrounds the opening of the evaporation container, and the opening of the evaporation container is configured to enter the inside of the cylindrical member, The organic compound monomer vapor flowing out from the openings of the two evaporation containers can be directly introduced into the cylindrical member without splashing around, allowing the use efficiency of the mixed organic compound monomer to be improved. become.
In this case, if a shielding plate for preventing the organic compound monomer from escaping downward is provided between the two evaporation containers as in the invention described in claim 2 , the use efficiency of the organic compound monomer is further increased. It becomes possible.
Furthermore, if a heating element for correcting the film thickness distribution is provided in the cylindrical member as in the third aspect of the invention, mixing of the organic compound monomer is further promoted.
In this case, as in the invention described in claim 4 , if a heating element for correcting the film thickness distribution is used which is heated by heat conduction from the surroundings, it is not necessary to provide a means for heating the heating element.
Furthermore, as in the invention described in claim 5, if the heating element for correcting the film thickness distribution is arranged so as to be parallel to the substrate at a position corresponding to the center of the substrate, the film thickness can be further increased. It becomes possible to improve uniformity .
On the other hand, if the evaporation source for an organic compound according to any one of claims 1 to 5 is provided in the vacuum processing chamber as in the invention according to claim 6, the use efficiency of the organic compound monomer is high, and furthermore, on the substrate. It is possible to easily obtain a vapor deposition polymerization apparatus capable of uniforming the film thickness distribution of the polymer thin film.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an organic compound evaporation source and a vacuum processing apparatus using the same according to the present invention will be described below in detail with reference to the drawings.
[0013]
FIG. 1 shows a preferred embodiment of a vapor deposition polymerization apparatus to which the present invention is applied.
As shown in FIG. 1, this vapor deposition polymerization apparatus 1 has a processing chamber 2 capable of maintaining an airtight state, and this processing chamber 2 is connected to an external vacuum pump (not shown) or other vacuum exhaust system. A substrate 3 as a base on which a polymer thin film is to be formed is held downward by the substrate holder 4 in the upper part of the processing chamber 2, and the substrate 3 is placed at a desired temperature on the back side of the substrate holder 4. A heater 5 for heating is provided. Here, as the substrate 3, a silicon wafer, a glass substrate, a metal plate, a plastic substrate or the like is used.
[0014]
On the other hand, an evaporation source 6 for evaporating the organic compound monomers A and B is provided below the processing chamber 2. In the present embodiment, evaporating containers 7 and 8 made of glass, for example, are provided, and heating heaters 9 and 10 are provided inside the evaporating containers 7 and 8. In addition, the inside of each of the evaporation containers 7 and 8 is provided with a thermocouple similar to that of the first conventional example described above, whereby the temperature of the organic compound monomers A and B and the evaporation rate are always kept constant. Configured as follows.
[0015]
As shown in FIG. 1, in the present embodiment, an evaporation control tank 6 </ b> A is provided above each evaporation container 7, 8. The evaporation control tank 6 </ b> A includes a cylindrical member 11 that is a cylindrical member and a shutter 13.
[0016]
The cylindrical member 11 is made of a metal such as stainless steel, the opening 7a of the opening of one of which the evaporation vessel 7,8, surrounds the 8a, arranged such other opening is against toward the substrate 3 Is done. Then, configured such that the opening on the side pair toward the substrate 3 of the cylindrical member 11 is opened and closed as required by a shutter 13.
[0017]
On the other hand, as shown in FIG. 1, the vapors of the organic compound monomers A and B flowing out from the openings 7a and 8a of the respective evaporation containers 7 and 8 are mixed without being scattered around and led to the substrate 3, The openings 7 a and 8 a of the evaporation containers 7 and 8 are configured to enter the inside of the cylindrical member 11. A heating heater 12 connected to a power source (not shown) is wound around the cylindrical member 11. Further, a shielding plate 15 is provided between the evaporation containers 7 and 8 so as not to let the organic compound monomers A and B escape downward.
[0018]
In such a configuration, when a polymer thin film is formed on the substrate 3, the degree of vacuum in the processing chamber 2 is adjusted, and the respective organic compound monomers A and B are brought to a predetermined temperature with the shutter 13 closed. Heat to keep. Thereafter, steam is generated from the evaporation ports 7a and 8a of the evaporation containers 7 and 8, and the vapors of the organic compound monomers A and B are introduced into the evaporation control tank 6A. On the other hand, the cylindrical member 11 is heated by the heater 12 wound around the cylindrical member 11, and the vapors of the organic compound monomers A and B are maintained at a predetermined temperature.
[0019]
Next, after each organic compound monomer A, B reaches a predetermined temperature and a required evaporation amount is obtained, the shutter 13 is opened, and a thin film of the organic compound is evaporated and deposited on the substrate 3 at a predetermined deposition rate. After that, the shutter 13 is closed and a polymerization reaction is caused on the substrate 3 to form a polymer thin film.
[0020]
In the present embodiment having such a configuration, the vapors of the organic compound monomers A and B flowing out from the openings 7a and 8a of the evaporation containers 7 and 8 are temporarily stored in the evaporation control tank 6A. At this time, it is reflected by the inner wall surface of the cylindrical member 11, and as a result, the mixing of the vapors of the organic compound monomers A and B is promoted. If the vapors of the organic compound monomers A and B are guided to the substrate 3 in that state, the vapors of the organic compound monomers A and B reach the substrate in a uniform state. Is formed.
[0021]
Further, since the heater 12 is provided around the cylindrical member 11, most of the vapors of the organic compound monomers A and B evaporated from the evaporation containers 7 and 8 reach the substrate 3, As a result, the use efficiency of each organic compound monomer A and B can be maintained at a high level.
[0022]
As described above, according to the present embodiment, a vacuum processing apparatus can be easily obtained in which the use efficiency of the organic compound monomers A and B is high and the film thickness distribution of the polymer thin film on the substrate 3 can be made uniform.
[0023]
FIG. 2 shows another embodiment of the vapor deposition polymerization apparatus to which the present invention is applied. Hereinafter, portions corresponding to those in the above embodiment will be described with the same reference numerals.
As shown in FIG. 2, in the vapor deposition polymerization apparatus 1 </ b> A according to the present embodiment, a heating element 14 for correcting the film thickness distribution is provided in the evaporation control tank 6 </ b> A and in the vicinity of the shutter 13. The heating element 14 is made of a metal material such as stainless steel and has a disk shape. For example, the heating element 14 is disposed in a horizontal direction so as to be parallel to the substrate 3 at a position corresponding to the central portion of the substrate 3.
[0024]
According to the present embodiment having such a configuration, the temperature of the heating element 14 increases as the temperature in the processing chamber 2 rises, and steam convection occurs in the vicinity of the heating element 14. Mixing of the organic compound monomers A and B is further promoted. As a result, a more uniform polymer thin film can be formed on the substrate 3.
[0025]
In this case, since the heating element 14 is heated by heat conduction from the surroundings, it is not particularly necessary to provide a means for heating the heating element 14, and the vapor deposition polymerization apparatus 1A having a simple configuration can be obtained. Since other configurations and operational effects are the same as those of the above-described embodiment, detailed description thereof is omitted.
[0026]
The present invention is not limited to the above-described embodiment, and various changes can be made.
For example, various materials can be used for the cylindrical member and the heating element. However, it is more effective to use a metal such as stainless steel having a high thermal conductivity.
[0027]
Various shapes and sizes of the cylindrical member can be used as long as the vapor of the organic compound monomer can be guided to the substrate. However, it is more effective to use a cylindrical shape corresponding to the shape and size of the substrate on which the polymer thin film is to be formed.
[0028]
On the other hand, the shape of the heating element is not limited to the disk shape, but can be various. However, the use of the disk shape has an advantage that it is advantageous for uniforming the film thickness in the horizontal direction.
[0029]
【Example】
Hereinafter, examples of the evaporation source according to the present invention and a vapor deposition polymerization apparatus using the same will be described in detail together with comparative examples.
[0030]
[Example 1]
A polyurea film was formed on the substrate 3 using the evaporation source and vapor deposition polymerization apparatus shown in FIG.
In this case, the substrate 3 was a square glass plate having a side of 120 mm or a Si wafer having a diameter of 5 inches (12.7 mm). The cylindrical member 11 was made of stainless steel having an outer diameter of 100 mm and a height of 220 mm, and the peripheral wall was heated to 100 ° C. by the heater 12. Then, 50 cm ³ of 4,4′-diphenylmethane diisocyanate (MDI) as an organic compound monomer A is injected into the evaporation container 7 and heated to 78 ° C., and as the organic compound monomer B as an organic compound monomer B, 4, 4 '-Diaminodiphenylmethane (MDA) was injected at 50 cm ³ and heated to 109 ° C.
[0031]
The inner diameters of the openings 7a and 8a of the respective evaporation containers 7 and 8 were 20 mm, and the distance between the openings 7a and 8a was 20 mm. Further, the distance between the openings 7a and 8a of the respective evaporation containers 7 and 8 and the substrate 3 was set to 300 mm, and the distance between the shutter 13 and the substrate 3 was set to 80 mm. The film thickness distribution of the polyurea film obtained by this apparatus is shown in FIG.
[0032]
[Comparative example]
As a comparative example, a polyurea film was formed on the substrate 3 using an apparatus having the same configuration as that of the conventional example, that is, an apparatus similar to that of Example 1 except that the cylindrical member 11 was not provided. The film thickness distribution of the polyurea film obtained by this apparatus is shown in FIG.
[0033]
As understood from FIG. 3, in the case of the vapor deposition polymerization apparatus using the evaporation source of the present invention, the film thickness distribution was improved as compared with the vapor deposition polymerization apparatus using the conventional evaporation source. For example, at a position 50 mm away from the central portion of the substrate 3, in the case of Comparative Example 1, only a film thickness of 50% or less of the central portion was obtained, whereas in the case of Example 1, 73 compared with the central portion. % Film thickness was obtained, resulting in a uniform film thickness distribution.
Further, the film formation speed of the polyurea film was able to be formed at a speed about 5 times that of Comparative Example 1.
[0034]
[Example 2]
In this example, a polyurea film was formed on the substrate 3 by the same method as in Example 1 using the vapor deposition polymerization apparatus 1A shown in FIG. In this case, as the heating element 14, a disk-shaped member made of stainless steel having a diameter of 30 mm was used, and was arranged so as to be parallel to the substrate 3 at a position corresponding to the central portion of the substrate 3. When the organic compound monomers A and B were evaporated in this vapor deposition polymerization apparatus 1A, the heating element 14 rose to 92 ° C. due to heat conduction from the surroundings.
[0035]
FIG. 4 shows the film thickness distribution of the polyurea film obtained by the apparatus of Example 2. As shown by the plot connecting the circles in FIG. 4, in the case of this example, at a position 50 mm away from the center of the substrate 3, the difference in film thickness from the center is about ± 4%. A more uniform polyurea film was obtained than in the previous apparatus.
[0036]
On the other hand, the film thickness distribution in the apparatus of Example 2 was calculated by simulation using the Monte Carlo method. That is, a certain amount of monomer gas is introduced into a container having the same shape as the evaporation control tank 6A shown in FIG. 2, and a certain ratio (for example, 50%) of the gas reflected by the COS law (cosine law) and incident on the substrate remains as it is. The amount (distribution) of gas incident on a predetermined range of the substrate was determined as having been deposited. In this case, the direction in which the monomer gas scatters was determined using random numbers. The results are shown as a plot connecting the circles in FIG.
[0037]
As can be seen from FIG. 4, the calculation result almost coincided with the experimental value, and it was found that an evaporation source that can be easily controlled to the optimum film thickness distribution can be obtained even if the shape of the evaporation source changes.
[0038]
【The invention's effect】
As described above, according to the organic compound evaporation source and the vapor deposition polymerization apparatus according to the present invention, the use efficiency of the organic compound monomer can be improved, and a polymer thin film having a uniform film thickness can be formed on the substrate. can do.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an embodiment of a vapor deposition polymerization apparatus to which the present invention is applied. FIG. 2 is a schematic configuration diagram showing another embodiment of a vapor deposition polymerization apparatus to which the present invention is applied. FIG. 4 is a graph showing the thickness distribution of the polyurea film when the evaporation source of the present invention and the conventional evaporation source are used. FIG. 4 is a graph showing the thickness distribution of the polyurea film obtained by the apparatus of Example 2. FIG. 5 is a schematic configuration diagram showing an example of a conventional vapor deposition polymerization apparatus. FIG. 6 is a schematic configuration diagram showing an example of a conventional evaporation source.
DESCRIPTION OF SYMBOLS 1, 1A ... Deposition polymerization apparatus, 2 ... Processing chamber, 3 ... Substrate, 5 ... Heater, 6 ... Evaporation source, 6A ... Evaporation control tank, 7, 8 ... Evaporation container, 7a, 8a ... Opening part, 9, 10 ... heater, 11 ... cylindrical member, 12 ... heater, 13 ... shutter, 14 ... heating element , 15 ... shielding plate

Claims

In an organic compound evaporation source that heats and vaporizes different organic compound monomers contained in two evaporation containers in a vacuum processing chamber,
Providing an evaporation control tank having a cylindrical member for mixing and guiding the vapor of the organic compound monomer flowing out from the openings of the two evaporation containers to the substrate without scattering to the surroundings ;
One opening of the cylindrical member surrounds the opening of the evaporation container, and the opening of the evaporation container is configured to enter the inside of the cylindrical member. source.

2. The organic compound evaporation source according to claim 1 , wherein a shielding plate is provided between the two evaporation containers so as not to allow the organic compound monomer to escape downward .

Organic compound for the evaporation source according to any one of claims 1 or 2, characterized in that a heating element is provided for the film thickness distribution correction in the tubular member.

4. The organic compound evaporation source according to claim 3 , wherein the heating element for correcting the film thickness distribution comprises a member heated by heat conduction from the surroundings.

5. The organic material according to claim 1, wherein the heating element for correcting the film thickness distribution is disposed at a position corresponding to the central portion of the substrate so as to be parallel to the substrate. Evaporation source for compounds.

A vapor deposition polymerization apparatus comprising the organic compound evaporation source according to any one of claims 1 to 5 in a vacuum processing chamber.