JP3755814B2 - Heat treatment method and heat treatment apparatus - Google Patents

Description

と近似することができる（図８参照）。ここで、ｎは時間ｔ’までに検出した熱処理温度の検出回数、Ａ_ＰはポイントＰにおいて、一定時間ｔ毎に検出された温度の総和（以下に積算温度という）である。
【００５４】
熱処理温度が安定した後は、ウエハＷの面内に供給される熱量は等しく、積算熱量に差は生じないことから、熱処理時の積算熱量を、ウエハＷの同心円上の複数箇所Ｐ１〜Ｐ４で等しくするには、熱処理開始から熱処理温度が安定するまでの積算熱量の差を、熱処理温度が安定した後に相殺するように、ヒータ２６の各出力量を制御すればよい。
【００５５】
実施形態では、まず、各ポイントＰにおけるダミーウエハＤＷの熱処理開始から熱処理温度が安定するまでの積算熱量Ｓ_Ｐを計算すると共に、積算熱量Ｓ_Ｐの中から最小値Ｓ_ｍｉｎを求め、積算熱量Ｓ_Ｐと積算熱量の最小値Ｓ_ｍｉｎとの積算熱量差ΔＳ_Ｐを計算する（図９参照）。この積算熱量差ΔＳ_Ｐは、

より、積算温度Ａ_Ｐと積算温度の最小値Ａ_ｍｉｎとの差から計算すればよい。
【００５６】
次に、ウエハＷの熱処理を開始し、ウエハＷの熱処理温度が安定した後に、この積算熱量差ΔＳ_Ｐを相殺するように、予め求めておいたポイントＰに対応するヒータ２６の出力量とポイントＰの温度との関係に基づいて、ヒータ２６の出力量を調整して温度をＴ_ｃ下げると共に、補正時間ｔ_ｃだけ保てばよい（図１０参照）。
【００５７】
例えば、ポイント１における積算温度Ａ_１と積算温度の最小値Ａ_ｍｉｎとの差が５０（℃）で、ポイント１に対応するヒータ２６ａの出力量を９０％から５０％に下げると、ウエハＷのポイント１の温度が２℃下がることが分かっている時は、
ΔＳ_Ｐ１＝２×ｔ_ｃとなればよいので、

より、２５秒間ヒータ２６ａの出力量を下げるように制御すればよい。
【００５８】
なお、上記説明では、ウエハＷの各ポイントＰの温度を１秒ごとに検出した場合について説明したが、検出時間は任意でよく、検出時間が短いほど正確な積算熱量を求めることができ、熱処理を均一にすることができる。例えば、０．５秒ごとにウエハＷの温度を検出して積算熱量Ｓ_Ｐを計算した場合には、上述したのと同様にΔＳ_Ｐを計算し、熱処理温度が安定した後に、例えば熱処理温度を２℃下げて積算熱量を等しくする場合には、

より、計算した時間だけ、そのポイントＰに対応するヒータの出力量を下げればよい。
【００５９】
また、上記説明では、積算熱量差ΔＳ_Ｐを積算熱量の最小値Ｓ_ｍｉｎを基準にして計算したが、どのポイントの積算熱量を基準にしてもよく、例えば積算熱量の最大値を基準にすることもできる。
【００６０】
また、上記説明では、下げる温度Ｔ_ｃを先に決定して補正時間ｔ_ｃを計算する場合について説明したが、逆に補正時間ｔ_ｃを決定しておき、下げる温度Ｔ_ｃを計算して、予め求めておいたポイントＰに対応するヒータ２６の出力量とポイントＰの温度との関係に基づいて、ヒータ２６の出力量を調整することも勿論可能である。
【００６１】
◎第二実施形態
この発明の第二実施形態は、ウエハＷに塗布された化学増幅型レジストの各温度における酸の拡散反応を考慮して、ウエハＷの温度とウエハＷに塗布された塗布液の拡散係数との積を、熱処理時間で積分した値（以下に積算反応熱量Ｊという）が、ウエハＷの同心円上の複数箇所Ｐ１〜Ｐ４で等しくなるようにヒータ２６ａ〜２６ｄの各出力量を制御した場合である。
【００６２】
ここで、ポイントＰにおける任意の時間ｔ’までの積算反応熱量をＪ_Ｐとすると、一定時間ｔごとに検出したウエハＷの温度Ｔ_ｎと、温度Ｔ_ｎにおける拡散係数Ｄ_Ｔｎ（図１１参照）とを用いて、

と近似することができる（図１２参照）。ここで、ｎは時間ｔ’までに検出した熱処理温度の検出回数、Ｉ_ＰはポイントＰにおいて、一定時間ｔ毎に検出された温度Ｔ_ｎに、その温度における拡散係数Ｄ_Ｔｎを掛けた値の総和（以下に積算反応温度という）である。なお、拡散係数Ｄ_Ｔｎは、予め温度との関係を実験で求めておき、その近似式をＣＰＵ５９に入力しておく。
【００６３】
熱処理温度が安定した後は、ウエハＷの面内温度は等しく、また、温度が等しければ拡散係数Ｄ_Ｔｎも等しいので、積算反応熱量に差は生じない。したがって、熱処理時の積算反応熱量Ｊ_Ｐを、ウエハＷの同心円上の複数箇所Ｐ１〜Ｐ４で等しくするには、熱処理開始から熱処理温度が安定するまでの積算反応熱量Ｊ_Ｐの差を、熱処理温度が安定した後に相殺するように、ヒータ２６の出力量を制御すればよい。
【００６４】
実施形態では、まず、各ポイントＰにおけるダミーウエハの熱処理開始から熱処理温度が安定するまでの積算反応熱量Ｊ_Ｐを計算すると共に、積算反応熱量Ｊ_Ｐの中から最小値Ｊ_ｍｉｎを求め、積算反応熱量Ｊ_Ｐと積算反応熱量の最小値Ｊ_ｍｉｎとの積算反応熱量差ΔＪ_Ｐを計算する（図１３参照）。この積算反応熱量差ΔＪ_Ｐは、

より、積算反応温度Ｉ_Ｐと積算反応温度の最小値Ｉ_ｍｉｎとの差から計算すればよい。
【００６５】
次に、ウエハＷの熱処理を開始し、ウエハＷの熱処理温度が安定した後に、この積算反応熱量差ΔＪ_Ｐを相殺するように、予め求めておいたポイントＰに対応するヒータ２６の出力量とポイントＰの温度との関係に基づいて、一定時間ヒータ２６の出力量を調整して温度をＴ_ｃ下げると共に、補正時間ｔ_ｃだけ保てばよい（図１４参照）。
【００６６】
例えば熱処理温度が１４０℃で安定した時に、ポイント１における積算反応熱量差ΔＪ_Ｐ１が１５８で、ポイント１に対応するヒータ２６ａの出力量を９０％から５０％に下げると、ウエハＷのポイント１の温度が２℃下がることが分かっている時は、１４０℃の拡散係数がＤ_１４０＝１．０、１３８℃の拡散係数がＤ_１３８＝０．９、ΔＪ_Ｐ１を相殺する補正時間をｔ_ｃとすると、ΔＪ_Ｐ１＝（Ｄ_１４０×１４０−Ｄ_１３８×１３８）×ｔ_ｃとなればよいので、

より、１０秒間ヒータ２６ａの出力量を下げるように制御すればよい。
【００６７】
なお、上記説明では、積算反応熱量差ΔＪ_Ｐを積算反応熱量の最小値Ｊ_ｍｉｎを基準にして計算したが、どのポイントの積算反応熱量を基準にしてもよく、例えば積算反応熱量の最大値を基準にすることもできる。
【００６８】
また、上記説明では、下げる温度Ｔ_ｃを先に決定して補正時間ｔ_ｃを計算する場合について説明したが、逆に補正時間ｔ_ｃを決定しておき、下げる温度Ｔ_ｃを計算して、予め求めておいたポイントＰに対応するヒータ２６の出力量とポイントＰの温度との関係に基づいて、ヒータ２６の出力量を調整することも勿論可能である。
【００６９】
◎第三実施形態
上記第一、第二実施形態では、予めダミーウエハＤＷを用いて得られた温度情報に基づいて、熱処理時におけるウエハＷの面内の熱影響が等しくなるように、ヒータ２６の出力量を制御する場合について説明したが、この温度情報は、熱処理時に直接ウエハＷから検出するようにしてもよい。その場合にも、昇温時の温度情報に基づいて、積算熱量差ΔＳ_Ｐ、積算反応熱量差ΔＪ_Ｐを計算し、ウエハＷの熱処理温度が安定した後に、この積算熱量差ΔＳ_Ｐ、積算反応熱量差ΔＪ_Ｐを相殺するように、ポイントＰに対応するヒータ２６の出力量とポイントＰの温度との関係に基づいて、一定時間ヒータ２６の出力量を下げればよい。
【００７０】
この場合、上記ギャップピン７０を載置台２５の同心円上の複数箇所に設け、このギャップピン７０に熱伝対等の温度検出手段を内蔵し、ウエハＷの同心円上の複数箇所Ｐ１〜Ｐ４の温度を測定するように構成すれば、熱伝対によるウエハＷの面内への熱影響を最小限に抑えることができる。
【００７１】
◎第四実施形態
また、上記第一ないし第三実施形態では、ヒータ２６を載置台２５の同心円上の４箇所に設け、それぞれのヒータ２６ａ〜２６ｄに対応するダミーウエハＤＷ又はウエハＷの同心円上の４箇所のポイントＰ１〜Ｐ４の熱処理時の温度情報を、熱伝対５８ａ〜５８ｄによって検出し、その温度情報に基づいて、熱処理時におけるウエハＷの面内の熱影響が等しくなるようにヒータ２６ａ〜２６ｄの出力量を制御する場合について説明したが、ヒータの数や温度を検出するポイントの数はこれに限らず、別の構成とすることもできる。例えば、図１５に示すように、載置台２５の一番外側のヒータを更に４つに分割して７つのヒータ２６ａ〜２６ｇを設け、図１６に示すように、それぞれのヒータ２６ａ〜２６ｇに対応するダミーウエハＤＷ又はウエハＷの同心円上の７箇所のポイントＰ１〜Ｐ７の熱処理時の温度情報を検出する熱伝対５８ａ〜５８ｇを設けるように構成することができる。この場合、上記温度情報に基づいて、熱処理時におけるウエハＷの面内の熱影響が等しくなるようにヒータ２６ａ〜２６ｇの出力量を制御することができるので、熱が逃げやすく、温度差が生じやすい外周部の熱処理を更に確実に均一にすることができる。なお、図１５、図１６において、その他の部分は上記第一ないし第三実施形態と同じであるので、同一箇所には同一符号を付して、その説明は省略する。
【００７２】
なお、上記実施形態においては、熱処理温度が安定した後にヒータ２６の出力量を制御する場合について説明したが、積算熱量Ｓ_Ｐ又は積算反応熱量Ｊ_Ｐを等しくできれば、昇温時等にヒータ２６の出力量を制御することも、勿論可能である。
【００７３】
また、上記実施形態においては、昇温時の積算熱量差ΔＳ又は積算反応熱量差ΔＪのみを、熱処理温度が安定した後にヒータ２６の出力量を制御して相殺する場合について説明したが、熱処理が終了した後の冷却時における積算熱量差ΔＳ又は積算反応熱量差ΔＪも相殺するようにヒータ２６の出力量を制御すれば、更に均一な熱処理を施すことができる。
【００７４】
【発明の効果】
以上に説明したように、この発明によれば、上記のように構成されているので、以下のような効果が得られる。
【００７５】
１）請求項１，５記載の発明によれば、予め測定用基板の同心円上の複数箇所における熱処理時の温度情報を、測定用基板の熱処理を開始してから熱処理温度が安定するまでの時間の間で検出し、温度情報の温度と安定するまでの時間との間の積算熱量を求めると共に、求められた積算熱量に基づいて、複数箇所それぞれの積算熱量の差を求め、熱処理における被処理体の加熱処理温度が安定した後に、積算熱量の差を相殺させるように、載置台の同心円上に複数形成された熱源の各出力量を制御するので、被処理体に供給される熱量を面内で等しくすることができ、被処理体の熱処理を均一にすることができ、歩留まりの向上を図ることができる。
【００７６】
２）請求項２，６記載の発明によれば、予め化学増幅型レジストの温度と酸の拡散反応との関係から拡散係数を求めておき、被処理体の同心円上の複数箇所における熱処理時の温度情報を検出し、上記拡散係数と温度情報から積算反応熱量を求め、熱処理時における被処理体の面内の積算反応熱量が等しくなるように、載置台の同心円上に複数形成された熱源の各出力量を制御するので、熱処理を行っている被処理体の熱影響を直接制御することができる。したがって、被処理体の面内の熱処理を確実に均一にして、歩留まりの向上を図ることができる。
【００７８】
３）請求項３記載の発明によれば、被処理体の温度と被処理体に塗布された塗布液の拡散係数との積を、熱処理時間で積分した値（積算反応熱量）が、被処理体の同心円上の複数箇所で等しくなるように熱源の各出力量を制御するので、上記１）、２）に加えて更に被処理体に塗布された塗布液の反応に直接寄与する熱量を面内で等しくすることができ、被処理体の熱処理を更に均一にすることができる。
【００７９】
４）請求項４，７記載の発明によれば、熱源の各出力量の制御を、熱処理温度が被処理体の面内で安定した後に、積算反応熱量の差を相殺させるようにして行うので、上記３）に加えて更に正確に制御することができ、熱処理を確実に均一にすることができる。
【００８０】
５）請求項８記載の発明によれば、温度検出手段を、被処理体を載置台上に隙間をもたせて支持するギャップピンに設けるので、上記２）に加えて更に温度検出手段による被処理体の面内への熱影響を最小限に抑えることができ、被処理体の熱処理を均一にすることができる。
【図面の簡単な説明】
【図１】この発明の熱処理装置を適用したレジスト液塗布・現像処理システムの一例を示す概略平面図である。
【図２】上記レジスト液塗布・現像処理システムの概略正面図である。
【図３】上記レジスト液塗布・現像処理システムの概略背面図である。
【図４】この発明に係る熱処理装置の一例を示す概略断面図である。
【図５】この発明に係る熱処理装置の一例を示す概略平面図である。
【図６】この発明に係る熱処理装置の温度検出手段の位置を示す概略平面図である。
【図７】被処理体を加熱処理したときの熱処理時間と被処理体の温度及び積算熱量の関係を示す説明図である。
【図８】被処理体を加熱処理したときの積算温度と積算熱量の関係を示す説明図である。
【図９】被処理体の任意の箇所における積算熱量差を示す説明図である。
【図１０】この発明の熱処理方法を用いた場合の被処理体の温度と積算熱量差を示す説明図である。
【図１１】被処理体の温度と被処理体の塗布液の拡散係数の関係を示す説明図である。
【図１２】被処理体を加熱処理した時の積算反応温度と積算反応熱量の関係を示す説明図である。
【図１３】被処理体の任意の箇所における積算反応熱量差を示す説明図である。
【図１４】この発明の熱処理方法を用いた場合の被処理体の温度と積算反応熱量差を示す説明図である。
【図１５】この発明に係る別の熱処理装置の一例を示す概略平面図である。
【図１６】この発明に係る別の熱処理装置の温度検出手段の位置を示す概略平面図である。
【符号の説明】
Ｗ 半導体ウエハ（被処理体）
ＤＷ ダミーウエハ（測定用基板）
２５ 載置台
２６ａ〜２６ｇ ヒータ（熱源）
５８ａ〜５８ｇ 熱伝対（温度検出手段）
５９ ＣＰＵ（制御手段）
７０ ギャップピン[0001]
[Industrial application fields]
The present invention relates to a heat treatment method and a heat treatment apparatus for heat-treating an object to be processed such as a semiconductor wafer or an LCD substrate on a mounting table.
[0002]
[Prior art]
In general, in the manufacturing process of a semiconductor integrated circuit, a photolithography technique is used to form a resist pattern on the surface of a semiconductor wafer, an LCD substrate, or the like (hereinafter referred to as a wafer). This photolithography technology includes a resist coating process for applying a resist solution to the surface of a wafer, an exposure process process for exposing a circuit pattern to the formed resist film, and a development for supplying a developer to the wafer after the exposure process. And processing steps.
[0003]
In addition, between the above processing steps, for example, a heat treatment performed between the resist coating step and the exposure processing step to evaporate the residual solvent in the resist film and improve the adhesion between the wafer and the resist film. (Pre-baking), heat treatment performed between the exposure process and the development process to prevent fringe generation or to induce an acid-catalyzed reaction in a chemically amplified resist (CAR) (Post-exposure bake (PEB)) and heating performed after the development process to remove residual solvent in the resist and the rinsing liquid incorporated in the resist during development, and to improve the penetration during wet etching Various heat treatments such as treatment (post bake) are performed.
[0004]
The above heat treatment is important because it affects the formation of the resist pattern, but in particular, when using a chemically amplified resist that has attracted attention in recent years because it can realize high sensitivity, high resolution, and high dry etching resistance. However, since the difference in the amount of heat given to each part of the resist film during PEB has a great influence on the circuit pattern formation in the final product, it is necessary to strictly control the heat treatment conditions.
[0005]
[Problems to be solved by the invention]
By the way, a conventional heat treatment apparatus has a heat source, for example, a heater having a mounting table that can heat the wafer to a predetermined temperature. However, since this mounting table easily escapes heat from the outer periphery, the outer periphery of the wafer is used. A large amount of heat is supplied to the central portion rather than the central portion, and there is a problem that the heat treatment cannot be made uniform. In order to solve this problem, a heat treatment apparatus that increases the resistance value of the heater wire at the outer peripheral portion to supply more heat to the outer peripheral portion than the central portion and balances the heat treatment temperature between the outer peripheral portion and the central portion. However, in this case, when the temperature is raised to the heat treatment temperature, a larger amount of heat is supplied in the outer peripheral portion than in the central portion of the wafer, so that the heat treatment becomes non-uniform.
[0006]
The present invention has been made in view of the above circumstances, and an object thereof is to provide a heat treatment method and a heat treatment apparatus capable of performing a uniform heat treatment on a semiconductor wafer, an LCD substrate, and the like.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the first heat treatment method of the present invention comprises: Detects temperature information when the measurement substrate provided with temperature detection means at multiple locations on the concentric circles is pre-heated in the time from the start of the heat treatment of the measurement substrate until the heat treatment temperature stabilizes And calculating the integrated heat amount between the step of storing in the control means for controlling the heat treatment and the temperature of the temperature information detected at each of the plurality of locations and the time to stabilize. A step of obtaining a difference in accumulated heat quantity at each of the plurality of locations based on the accumulated heat quantity, so that the difference in accumulated heat quantity is canceled after the heat treatment temperature of the workpiece in the heat treatment is stabilized. In The output amounts of a plurality of heat sources formed on the concentric circles of the mounting table are controlled (claim 1).
[0008]
Moreover, the second heat treatment method of the present invention comprises: Obtain the diffusion coefficient from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction in advance. Detect temperature information during heat treatment at a plurality of locations on the concentric circles of the object to be processed, Obtain the integrated reaction heat from the diffusion coefficient and the temperature information, In-plane of the object to be processed during heat treatment Integrated heat of reaction The output amounts of a plurality of heat sources formed on the concentric circles of the mounting table are controlled so as to be equal to each other (claim 2).
[0009]
In the heat treatment method of the present invention, The accumulated heat of reaction is The product of the temperature of the object to be processed and the diffusion coefficient of the coating liquid applied to the object to be processed is integrated by the heat treatment time. Can be requested (Claims 3 ). In this case, the control of each output amount of the heat source may be performed at the time of temperature increase, but after the heat treatment temperature is stabilized in the plane of the object to be processed. , So as to offset the difference in total reaction heat It is preferable to do this (claims) 4 ).
[0010]
A first heat treatment apparatus according to the present invention embodies the first heat treatment method, and includes a mounting table on which an object to be processed is mounted, and radiates heat from the surface of the mounting table to perform the above processing. On the premise of a heat treatment apparatus for performing heat treatment on the treatment body, a plurality of heat sources that are formed on the concentric circles of the mounting table and supply heat to the mounting table; Measurement substrate provided with temperature detecting means at a plurality of locations on concentric circles and temperature information when the measurement substrate is preheated until the heat treatment temperature is stabilized after the heat treatment of the measurement substrate is started. Control means for detecting and storing in time, wherein the control means calculates an integrated heat amount between the temperature of the temperature information detected at each of a plurality of locations on the concentric circles and the time until stabilization. In addition, the difference between the integrated heat amounts is calculated based on the calculated integrated heat amount, and the difference between the integrated heat amounts is canceled after the heat treatment temperature of the workpiece in the heat treatment is stabilized. Control each output amount of heat sources formed on the concentric circles of the table above (Claims) 5 ).
[0011]
A second heat treatment apparatus according to the present invention embodies the second heat treatment method, and includes a mounting table on which an object to be processed is mounted, and radiates heat from the surface of the mounting table to perform the above processing. On the premise of a heat treatment apparatus that heat-treats the treatment body, a plurality of heat sources that are formed on the concentric circles of the mounting table and supply heat to the mounting table; and Multiple locations on concentric circles Temperature detecting means for detecting the temperature; Control means for controlling each output amount of the heat source, and the control means obtains a diffusion coefficient from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction in advance, and Detect temperature information at the time of heat treatment at multiple locations on the concentric circles, find the integrated reaction calorie from the diffusion coefficient and the temperature information, In-plane of the object to be processed during heat treatment Total reaction heat So that Control each output amount of heat sources formed on the concentric circles of the table above (Claims) 6 ). in this case, It is preferable to control each output amount of the heat source by the control means so that the difference in accumulated reaction heat amount is canceled after the heat treatment temperature is stabilized in the surface of the object to be processed. Also, Preferably, the temperature detecting means is provided on a gap pin that supports the object to be processed with a gap provided on the mounting table.
[0012]
Claim 1, 5 According to the described invention, the temperature information at the time of heat treatment at a plurality of locations on the concentric circles of the measurement substrate is obtained in advance. Detected during the time from the start of the heat treatment of the measurement substrate until the heat treatment temperature becomes stable, and calculates the integrated heat amount between the temperature of the temperature information and the time until it stabilizes, and the obtained integrated heat amount Based on the above, find the difference in the accumulated heat amount of each of a plurality of locations, after the heat treatment temperature of the object to be processed in the heat treatment is stabilized, so as to cancel the difference in accumulated heat amount, Since each output amount of the heat source formed on the concentric circle of the mounting table is controlled, The amount of heat supplied to the object to be processed can be made equal in the plane, Heat treatment can be made uniform and yield can be improved.
[0013]
Claim 2, 6 According to the invention of Obtain the diffusion coefficient from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction in advance. Detect temperature information during heat treatment at multiple locations on the concentric circles of the workpiece, Calculate the total reaction heat from the diffusion coefficient and temperature information, In the surface of the workpiece during heat treatment Integrated heat of reaction Since the output amounts of the plurality of heat sources formed on the concentric circles of the mounting table are controlled so as to be equal to each other, it is possible to directly control the thermal influence of the object to be processed. Therefore, it is possible to ensure uniform heat treatment in the surface of the object to be processed and improve yield.
[0015]
Claims 3 According to the described invention, a value obtained by integrating the product of the temperature of the object to be processed and the diffusion coefficient of the coating liquid applied to the object to be processed by the heat treatment time. (Integrated reaction heat) However, since each output amount of the heat source is controlled so as to be equal at a plurality of locations on the concentric circles of the object to be processed, the amount of heat directly contributing to the reaction of the coating liquid applied to the object to be processed can be made equal in the plane. In addition, the heat treatment of the object to be processed can be made more uniform.
[0016]
Claim 4,7 According to the described invention, the control of each output amount of the heat source is performed after the heat treatment temperature is stabilized in the surface of the workpiece. To offset the difference in total reaction heat Since it is performed, it can be accurately controlled and the heat treatment can be made uniform uniformly.
[0017]
According to the eighth aspect of the present invention, since the temperature detecting means is provided on the gap pin that supports the object to be processed with a gap on the mounting table, the influence of heat on the surface of the object to be processed by the temperature detecting means is prevented. It can be minimized and the heat treatment of the object to be processed can be made uniform.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings. In this embodiment, a case where the heat treatment method and the heat treatment apparatus of the present invention are applied to a hot plate unit for performing heat treatment of a semiconductor wafer will be described.
[0019]
1 is a schematic plan view of an embodiment of a resist solution coating / development processing system, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a rear view of FIG.
[0020]
In the processing system, a plurality of semiconductor wafers W (hereinafter referred to as “wafers W”) as workpieces are carried into the system from the outside in the wafer cassette 1 in units of 25, for example, 25 units, or carried out of the system. A cassette station 10 (carrying unit) for carrying W in and out, and various single-wafer processing units for performing predetermined processing on the wafer W one by one in the coating and developing process are arranged in multiple stages at predetermined positions. A processing station 20 having the processing apparatus of the present invention and an interface unit 30 for transferring the wafer W between an exposure apparatus (not shown) provided adjacent to the processing station 20. The main part is composed.
[0021]
As shown in FIG. 1, the cassette station 10 includes a plurality of, for example, up to four wafer cassettes 1 at the position of the projection 3 on the cassette mounting table 2 with the respective wafer entrances facing the processing station 20 side. Wafer transfer tweezers 4 mounted in a line along the direction and movable in the cassette arrangement direction (X direction) and in the wafer arrangement direction (Z direction) of the wafer W accommodated in the wafer cassette 1 along the vertical direction. Is configured to be selectively transferred to each wafer cassette 1. Further, the wafer transfer tweezers 4 are configured to be rotatable in the θ direction, and are arranged in alignment units (ALIM) and extension units (EXT) belonging to a multi-stage unit portion of a third group G3 on the processing station 20 side described later. Can also be transported.
[0022]
As shown in FIG. 1, the processing station 20 is provided with a vertical transfer type main wafer transfer mechanism 21 at the center, and a set of all the processing units around a chamber 22 that accommodates the main wafer transfer mechanism 21. Alternatively, they are arranged in multiple stages over a plurality of sets. In this example, five sets G1, G2, G3, G4 and G5 have a multistage arrangement, and the first and second sets G1, G2 are arranged in parallel on the front side of the system (front side in FIG. 1). The multistage unit of the third group G3 is arranged adjacent to the cassette station 10, the multistage unit of the fourth group G4 is arranged adjacent to the interface part 30, and the multistage unit of the fifth group G5 is arranged on the back side. Is arranged.
[0023]
In this case, as shown in FIG. 2, in the first group G1, two spinner type processing units, for example, resists, which perform predetermined processing by placing the wafer W on a spin chuck (not shown) in the cup 23 A coating unit (COT) and a developing unit (DEV) for developing a resist pattern are stacked in two stages in order from the bottom in the vertical direction. Similarly, in the second group G2, two spinner type processing units, for example, a resist coating unit (COT) and a developing unit (DEV) are stacked in two stages from the bottom in the vertical direction. The reason why the resist coating unit (COT) is arranged on the lower side in this way is that the drain of the resist solution is troublesome both in terms of mechanism and maintenance. However, the resist coating unit (COT) can be arranged in the upper stage as required.
[0024]
As shown in FIG. 3, in the third group G3, an oven-type processing unit that performs a predetermined process by placing the wafer W on the wafer mounting table 24, for example, a cooling unit (COL) that cools the wafer W, and the wafer W Adhesion unit (AD) for performing hydrophobic treatment, alignment unit (ALIM) for aligning wafer W, extension unit (EXT) for loading / unloading wafer W, and four hot plate units for baking wafer W (HP) is stacked, for example, in eight steps in order from the bottom in the vertical direction. Similarly, the fourth group G4 is an oven-type processing unit such as a cooling unit (COL), an extension / cooling unit (EXTCOL), an extension unit (EXT), a cooling unit (COL), and two chilling hot plate units having a rapid cooling function. (CHP) and two hot plate units (HP) are stacked in, for example, eight stages in order from the bottom in the vertical direction.
[0025]
As described above, the cooling unit (COL) and the extension cooling unit (EXTCOL) having a low processing temperature are arranged in the lower stage, and the hot plate unit (HP), the chilling hot plate unit (CHP) and the adhesion unit having a high processing temperature. By disposing (AD) in the upper stage, it is possible to reduce thermal mutual interference between units. Of course, a random multi-stage arrangement is also possible.
[0026]
As shown in FIG. 1, in the processing station 20, the third and fourth sets G3 and G4 of multistage units (spinner type processing units) adjacent to the first and second sets of G1 and G2 (spinner type processing units) ( Ducts 65 and 66 are vertically cut in the side walls of the oven-type processing unit. Downflow clean air or specially temperature-adjusted air flows through these ducts 65 and 66. By this duct structure, the heat generated in the oven type processing units of the third and fourth groups G3 and G4 is cut off and does not reach the spinner type processing units of the first and second groups G1 and G2. ing.
[0027]
Further, in this processing system, a fifth stage G5 multi-stage unit can be arranged on the back side of the main wafer transfer mechanism 21 as shown by a dotted line in FIG. The multistage units of the fifth group G5 can move sideways along the guide rail 67 as viewed from the main wafer transfer mechanism 21. Therefore, even when the multi-stage unit of the fifth group G5 is provided, the space portion is secured by sliding the unit, so that the maintenance work can be easily performed from the back with respect to the main wafer transfer mechanism 21.
[0028]
The interface unit 30 has the same dimensions as the processing station 20 in the depth direction, but is made small in the width direction. A portable pickup cassette 31 and a stationary buffer cassette 32 are arranged in two stages on the front part of the interface part 30, a peripheral exposure device 33 is arranged on the back part, and a wafer is located in the center part. A transfer arm 34 is provided. The wafer transfer arm 34 is configured to move in the X and Z directions and transfer the cassettes 31 and 32 and the peripheral exposure apparatus 33. Further, the wafer transfer arm 34 is configured to be rotatable in the θ direction, and an extension unit (EXT) belonging to the multi-stage unit of the fourth group G4 on the processing station 20 side and a wafer transfer table (not shown) on the adjacent exposure apparatus side. 2) can be transported.
[0029]
The processing system configured as described above is installed in the clean room 40, and the cleanliness of each part is increased by an efficient vertical laminar flow method in the system.
[0030]
Next, the operation of the processing system will be described. First, in the cassette station 10, the tweezers 4 for wafer transfer access the cassette 1 containing unprocessed wafers W on the cassette mounting table 2, and take out one wafer W from the cassette 1. When the wafer tweezers 4 takes out the wafer W from the cassette 1, it moves to the alignment unit (ALIM) arranged in the multi-stage unit of the third group G3 on the processing station 20 side, and in the unit (ALIM) A wafer W is placed on the wafer mounting table 24. The wafer W undergoes orientation flat alignment and centering on the wafer mounting table 24. Thereafter, the main wafer transfer mechanism 21 accesses the alignment unit (ALIM) from the opposite side, and receives the wafer W from the wafer mounting table 24.
[0031]
In the processing station 20, the main wafer transfer mechanism 21 first carries the wafer W into an adhesion unit (AD) belonging to the multistage unit of the third group G3. Within this adhesion unit (AD), the wafer W is subjected to a hydrophobic treatment. When the hydrophobization process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the adhesion unit (AD), and then cools the cooling units (belonging to the third group G3 or the fourth group G4 multi-stage unit). COL). In this cooling unit (COL), the wafer W is cooled to a set temperature before the resist coating process, for example, 23 ° C. When the cooling process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the cooling unit (COL), and then to the resist coating unit (COT) belonging to the multistage unit of the first group G1 or the second group G2. Carry in. In this resist coating unit (COT), the wafer W is coated with a resist with a uniform film thickness on the wafer surface by spin coating.
[0032]
When the resist coating process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the resist coating unit (COT) and then loads it into the hot plate unit (HP). In the hot plate unit (HP), the wafer W is mounted on a mounting table and pre-baked at a predetermined temperature, for example, 100 ° C. for a predetermined time. As a result, the residual solvent can be removed by evaporation from the coating film on the wafer W. When pre-baking is completed, the main wafer transfer mechanism 21 unloads the wafer W from the hot plate unit (HP), and then transfers the wafer W to the extension cooling unit (EXTCOL) belonging to the multistage unit of the fourth group G4. Within this unit (COL), the wafer W is cooled to a temperature suitable for the peripheral exposure process in the next process, that is, the peripheral exposure apparatus 33, for example, 24 ° C. After this cooling, the main wafer transfer mechanism 21 transfers the wafer W to the extension unit (EXT) immediately above, and places the wafer W on a mounting table (not shown) in the unit (EXT). When the wafer W is mounted on the mounting table of the extension unit (EXT), the wafer transfer arm 34 of the interface unit 30 accesses from the opposite side to receive the wafer W. Then, the wafer transfer arm 34 carries the wafer W into the peripheral exposure apparatus 33 in the interface unit 30. Here, the wafer W is exposed to the edge portion.
[0033]
When the peripheral exposure is completed, the wafer transfer arm 34 unloads the wafer W from the peripheral exposure apparatus 33 and transfers it to a wafer receiving table (not shown) on the adjacent exposure apparatus side. In this case, the wafer W may be temporarily stored in the buffer cassette 32 before being transferred to the exposure apparatus.
[0034]
When the entire exposure is completed in the exposure apparatus and the wafer W is returned to the wafer receiving table on the exposure apparatus side, the wafer transfer arm 34 of the interface unit 30 accesses the wafer receiving table to receive and receive the wafer W. The wafer W is loaded into an extension unit (EXT) belonging to the multi-stage unit of the fourth group G4 on the processing station 20 side, and placed on the wafer receiving table. Also in this case, the wafer W may be temporarily stored in the buffer cassette 32 in the interface unit 30 before being transferred to the processing station 20 side.
[0035]
The wafer W placed on the wafer receiving table is transferred to the chilling hot plate unit (CHP) by the main wafer transfer mechanism 21 and subjected to a post-exposure baking process to induce an acid catalytic reaction.
[0036]
Thereafter, the wafer W is carried into a developing unit (DEV) belonging to the multistage unit of the first group G1 or the second group G2. In the developing unit (DEV), the wafer W is placed on a spin chuck, and the developer is uniformly applied to the resist on the surface of the wafer W by, for example, a spray method. When the development is completed, a rinse solution is applied to the surface of the wafer W to wash away the developer.
[0037]
When the developing process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the developing unit (DEV), and then the hot plate unit (HP) belonging to the third group G3 or the multistage unit of the fourth group G4. Carry in. In this unit (HP), the wafer W is post-baked for a predetermined time at 100 ° C., for example. Thereby, the resist swollen by development is cured, and chemical resistance is improved.
[0038]
When the post-baking is completed, the main wafer transfer mechanism 21 unloads the wafer W from the hot plate unit (HP), and then loads it into one of the cooling units (COL). Here, after the wafer W returns to room temperature, the main wafer transfer mechanism 21 next transfers the wafer W to the extension unit (EXT) belonging to the third group G3. When the wafer W is mounted on a mounting table (not shown) of the extension unit (EXT), the wafer transfer tweezers 4 on the cassette station 10 side accesses from the opposite side and receives the wafer W. The wafer transfer tweezers 4 put the received wafer W into a predetermined wafer storage groove of the processed wafer storage cassette 1 on the cassette mounting table, and the processing is completed.
[0039]
Next, a hot plate unit (HP) which is an embodiment of the heat treatment apparatus of the present invention will be described with reference to a sectional view of FIG.
[0040]
In the hot plate unit (HP), a processing chamber 50 for heat-processing the wafer W carried by the main wafer transfer mechanism 21 is formed. In the processing chamber 50, a shutter 51 for shutting off the outside air, a wafer A mounting table 25 for mounting W and a support pin 80 capable of moving the wafer W up and down on the mounting table 25 are provided.
[0041]
The shutter 51 is movable up and down by the operation of the elevating cylinder 52. When the shutter 51 is lifted, the shutter 51 and a stopper 55 suspended from a cover 54 having an exhaust port 53 at the upper center come into contact with each other. The interior of the chamber 50 is configured to be kept airtight. Further, the stopper 55 is provided with an air supply port (not shown), and the air flowing into the processing chamber 50 from the air supply port is exhausted from the exhaust port 53. The air flowing in from the air supply port is configured not to directly touch the wafer W in the processing chamber 50, and the wafer W can be heated at a predetermined processing temperature.
[0042]
As shown in FIG. 5, the mounting table 25 is formed in a disk shape larger than the wafer W, and a plurality of heat sources, for example, heaters 26 a to 26 d for heating the wafer W are arranged on the concentric circles at appropriate intervals. . The heater 26 can control each output amount based on temperature information detected by the thermocouples 58a to 58d at a plurality of locations P1 to P4 on the concentric circles of the wafer W or the dummy wafer DW (measuring substrate). It is connected to control means such as a central processing unit 59 (hereinafter referred to as CPU 59).
[0043]
On the mounting table 25, gap pins 70 for supporting the wafer W with a clearance from the mounting table 25 are attached to prevent particles and the like from adhering to the wafer W. Further, on the concentric circle of the mounting table 25, a plurality of, for example, three support pin guiding through holes 27 for the support pins 80 to enter and exit are provided at equal intervals. The mounting table 25 configured as described above is formed of a material having good thermal conductivity such as an aluminum alloy.
[0044]
The gap pin 70 has a base portion attached in a recess provided on the surface of the mounting table 25, and stands on the base portion to leave a gap of, for example, 0.1 to 0.3 mm from the mounting table 25. And is formed so that the difference between the heat applied to the wafer W from the gap pins 70 and the heat applied to the wafer W from the surface of the mounting table 25 is as small as possible. .
[0045]
As shown in FIG. 4, the lower portion of the support pin 80 is fixed to a connection guide 89, and the connection guide 89 is connected to a timing belt 88. The timing belt 88 is stretched over a driving pulley 86 driven by a stepping motor 81 and a driven pulley 87 disposed above the driving pulley 86, and the support pin is rotated by forward / reverse rotation of the stepping motor 81. 80 and the mounting table 25 are formed to be relatively movable up and down. Therefore, the support pins 80 can support the wafer W at a position indicated by a two-dot chain line, and when the support pins 80 are lowered from this state, the wafer W is placed on the mounting table 25 as indicated by a solid line. can do. Similarly to the gap pin 70 described above, the support pins 80 are also formed so that the difference between the heat applied from the support pins 80 to the wafer W and the heat applied from the surface of the mounting table 25 is as small as possible.
[0046]
Next, a heat treatment method using this hot plate unit (HP) will be described.
[0047]
First, using a hot plate unit (HP), the dummy wafer DW is heat-treated by setting all the heaters 26 to an equal output amount, for example, 90% of the maximum output amount. At this time, as shown in FIG. 6, the dummy wafer DW is provided with temperature detecting means, for example, thermocouples 58a to 58d at points P1 to P4 corresponding to the heaters 26a to 26d, and the temperature during the heat treatment is set at regular intervals. For example, detection is performed every second, and information on the detected temperature is input to the CPU 59. The detected temperature information is stored in the CPU 59.
[0048]
Further, after the heat treatment temperature is stabilized, the output amount of the heaters 26a to 26d is changed, and the relationship between the output amount of the heaters 26a to 26d and the temperature of each point P1 to P4 of the dummy wafer DW is detected and input to the CPU 59. Remember.
[0049]
Next, the heat treatment of the wafer W is started, and the control unit 59 sends an electrical signal to the heaters 26a to 26d based on the detection information, so that the heat effect in the surface of the wafer W during the heat treatment becomes equal. Control the output amount of ˜26d.
[0050]
Specifically, it can be controlled as follows.
[0051]
◎ First embodiment
In the first embodiment of the present invention, the output amounts of the heaters 26a to 26d are controlled so that the integrated heat amount supplied to the wafer W is equal at a plurality of locations P1 to P4 on the concentric circle of the wafer W. .
[0052]
Here, the integrated heat amount means the total amount of heat supplied to the arbitrary point P of the wafer W by the heat treatment up to an arbitrary time, but for convenience, the temperature at the arbitrary point P of the wafer W is vertically increased. The axis and the heat treatment time can be represented by an area S indicated by diagonal lines in FIG. 7, and if the areas are equal, the integrated heat amount becomes equal (hereinafter, S is referred to as the integrated heat amount).
[0053]
The accumulated heat amount S up to an arbitrary time t ′ at the point P _P Is the temperature T of the wafer W detected at regular intervals t. _n Using,

(See FIG. 8). Here, n is the number of detected heat treatment temperatures detected up to time t ′, A _P Is the sum of temperatures detected at a certain time t at point P (hereinafter referred to as integrated temperature).
[0054]
After the heat treatment temperature is stabilized, the amount of heat supplied into the surface of the wafer W is equal, and there is no difference in the accumulated heat amount. In order to make them equal, each output amount of the heater 26 may be controlled so that the difference in accumulated heat amount from the start of the heat treatment to the stabilization of the heat treatment temperature is canceled after the heat treatment temperature is stabilized.
[0055]
In the embodiment, first, the integrated heat amount S from the start of the heat treatment of the dummy wafer DW at each point P until the heat treatment temperature is stabilized. _P And the integrated heat quantity S _P Minimum value S from _min And calculate the integrated heat quantity S _P And minimum value S of accumulated heat _min Heat difference ΔS _P Is calculated (see FIG. 9). This accumulated heat difference ΔS _P Is

Accumulated temperature A _P And minimum temperature A _min Calculate from the difference between
[0056]
Next, the heat treatment of the wafer W is started, and after the heat treatment temperature of the wafer W is stabilized, the accumulated heat amount difference ΔS. _P In order to cancel out the above, the output amount of the heater 26 is adjusted based on the relationship between the output amount of the heater 26 corresponding to the point P and the temperature of the point P, which has been obtained in advance, so that the temperature T _c And the correction time t _c Need only be kept (see FIG. 10).
[0057]
For example, integrated temperature A at point 1 ₁ And minimum temperature A _min When the output of the heater 26a corresponding to the point 1 is reduced from 90% to 50%, the temperature of the point 1 of the wafer W is known to decrease by 2 ° C.
ΔS _P1 = 2 x t _c So

Thus, the output of the heater 26a may be controlled to be lowered for 25 seconds.
[0058]
In the above description, the case where the temperature of each point P of the wafer W is detected every second has been described. However, the detection time may be arbitrary, and the shorter the detection time, the more accurate the integrated heat quantity can be obtained. Can be made uniform. For example, the integrated heat quantity S is detected by detecting the temperature of the wafer W every 0.5 seconds. _P Is calculated in the same manner as described above. _P After the heat treatment temperature is stabilized, for example, when the heat treatment temperature is lowered by 2 ° C. and the integrated heat quantity is made equal,

Therefore, the output amount of the heater corresponding to the point P may be lowered by the calculated time.
[0059]
In the above description, the accumulated heat difference ΔS _P Is the minimum value S of accumulated heat _min However, the integrated heat quantity at any point may be used as a reference, for example, the maximum value of the integrated heat quantity may be used as a reference.
[0060]
In the above description, the lowering temperature T _c Is determined first and the correction time t _c However, the correction time t is reversed. _c Decrease the temperature T _c Of course, it is possible to adjust the output amount of the heater 26 based on the relationship between the output amount of the heater 26 corresponding to the point P and the temperature of the point P that have been obtained in advance.
[0061]
◎ Second embodiment
In the second embodiment of the present invention, the temperature of the wafer W and the diffusion coefficient of the coating solution applied to the wafer W are considered in consideration of the diffusion reaction of the acid at each temperature of the chemically amplified resist applied to the wafer W. This is a case in which each output amount of the heaters 26a to 26d is controlled so that a value obtained by integrating the product by the heat treatment time (hereinafter referred to as an integrated reaction heat amount J) becomes equal at a plurality of locations P1 to P4 on the concentric circles of the wafer W. .
[0062]
Here, the cumulative reaction heat amount up to an arbitrary time t ′ at the point P is expressed as J _P Then, the temperature T of the wafer W detected every fixed time t _n And temperature T _n Diffusion coefficient D _Tn (See FIG. 11)

(See FIG. 12). Here, n is the number of detected heat treatment temperatures detected up to time t ′, and I _P Is the temperature T detected at a certain time t at point P. _n And the diffusion coefficient D at that temperature _Tn The sum of the values multiplied by (hereinafter referred to as the integrated reaction temperature). The diffusion coefficient D _Tn , A relationship with temperature is obtained in advance by experiment, and an approximate expression thereof is input to the CPU 59.
[0063]
After the heat treatment temperature is stabilized, the in-plane temperature of the wafer W is equal, and if the temperatures are equal, the diffusion coefficient D _Tn Therefore, there is no difference in the integrated reaction heat quantity. Therefore, cumulative reaction heat amount J during heat treatment _P Is equalized at a plurality of locations P1 to P4 on the concentric circles of the wafer W, the accumulated reaction heat amount J from the start of the heat treatment to the stabilization of the heat treatment temperature. _P The output amount of the heater 26 may be controlled so that the difference is canceled out after the heat treatment temperature is stabilized.
[0064]
In the embodiment, first, the accumulated reaction heat amount J from the start of the heat treatment of the dummy wafer at each point P until the heat treatment temperature becomes stable is described. _P As well as the integrated reaction calorie J _P Minimum value J _min The integrated reaction calorie J _P And minimum value of total reaction heat J _min Difference in total reaction heat ΔJ _P Is calculated (see FIG. 13). This accumulated reaction calorie difference ΔJ _P Is

From the integrated reaction temperature I _P And minimum reaction temperature I _min Calculate from the difference between
[0065]
Next, the heat treatment of the wafer W is started, and after the heat treatment temperature of the wafer W is stabilized, this accumulated reaction heat difference ΔJ _P The temperature of the heater 26 is adjusted by adjusting the output amount of the heater 26 for a certain period of time based on the relationship between the output amount of the heater 26 corresponding to the point P and the temperature of the point P determined in advance. _c And the correction time t _c Need only be kept (see FIG. 14).
[0066]
For example, when the heat treatment temperature is stabilized at 140 ° C., the cumulative reaction heat difference ΔJ at point 1 _P1 If the output of the heater 26a corresponding to the point 1 is reduced from 90% to 50% when the temperature of the point 1 of the wafer W is 2 ° C. lower, the diffusion coefficient of 140 ° C. is D ₁₄₀ = 1.0, diffusion coefficient of 138 ° C is D ₁₃₈ = 0.9, ΔJ _P1 Correction time to cancel _c Then ΔJ _P1 = (D ₁₄₀ × 140-D ₁₃₈ × 138) × t _c So

Accordingly, the output amount of the heater 26a may be controlled to be lowered for 10 seconds.
[0067]
In the above description, the cumulative reaction heat difference ΔJ _P Is the minimum value of total reaction heat J _min However, the accumulated reaction heat quantity at any point may be used as a reference, for example, the maximum value of the integrated reaction heat quantity may be used as a reference.
[0068]
In the above description, the lowering temperature T _c Is determined first and the correction time t _c However, the correction time t is reversed. _c Decrease the temperature T _c Of course, it is possible to adjust the output amount of the heater 26 based on the relationship between the output amount of the heater 26 corresponding to the point P and the temperature of the point P that have been obtained in advance.
[0069]
◎ Third embodiment
In the first and second embodiments, the output amount of the heater 26 is controlled based on the temperature information obtained in advance using the dummy wafer DW so that the thermal effects in the surface of the wafer W during the heat treatment become equal. Although the case has been described, this temperature information may be detected directly from the wafer W during the heat treatment. Even in this case, based on the temperature information at the time of temperature increase, the integrated heat quantity difference ΔS _P , Accumulated reaction calorie difference ΔJ _P And after the heat treatment temperature of the wafer W is stabilized, this accumulated heat difference ΔS _P , Accumulated reaction calorie difference ΔJ _P Therefore, the output amount of the heater 26 may be reduced for a certain period of time based on the relationship between the output amount of the heater 26 corresponding to the point P and the temperature of the point P.
[0070]
In this case, the gap pins 70 are provided at a plurality of locations on concentric circles of the mounting table 25, and temperature detection means such as a thermocouple is built in the gap pins 70, and the temperatures at the plurality of locations P 1 to P 4 on the concentric circles of the wafer W are adjusted. If it is configured to measure, it is possible to minimize the thermal effect of the thermocouple on the surface of the wafer W.
[0071]
◎ Fourth embodiment
In the first to third embodiments, the heaters 26 are provided at four locations on the concentric circles of the mounting table 25, and the four points P1 on the concentric circles of the dummy wafer DW or the wafer W corresponding to the respective heaters 26a to 26d. -P4 temperature information during the heat treatment is detected by the thermocouples 58a-58d, and based on the temperature information, the output amounts of the heaters 26a-26d so that the thermal effects in the surface of the wafer W during the heat treatment become equal. However, the number of heaters and the number of points at which the temperature is detected are not limited to this, and other configurations may be used. For example, as shown in FIG. 15, the outermost heater of the mounting table 25 is further divided into four to provide seven heaters 26a to 26g. As shown in FIG. 16, each heater 26a to 26g is supported. The thermocouples 58a to 58g for detecting temperature information at the time of heat treatment of the seven points P1 to P7 on the concentric circles of the dummy wafer DW or the wafer W to be configured can be provided. In this case, the output amount of the heaters 26a to 26g can be controlled based on the temperature information so that the thermal effects in the surface of the wafer W during the heat treatment become equal, so that heat easily escapes and a temperature difference occurs. The easy heat treatment of the outer peripheral portion can be made more uniform. In FIG. 15 and FIG. 16, the other parts are the same as those in the first to third embodiments.
[0072]
In the above embodiment, the case where the output amount of the heater 26 is controlled after the heat treatment temperature is stabilized has been described. _P Or cumulative reaction heat J _P Of course, it is possible to control the output amount of the heater 26 at the time of temperature rise or the like.
[0073]
In the above embodiment, only the accumulated heat difference ΔS or accumulated reaction heat difference ΔJ at the time of temperature rise has been described for the case where the output amount of the heater 26 is controlled and canceled after the heat treatment temperature is stabilized. If the output amount of the heater 26 is controlled so as to cancel out the accumulated heat amount difference ΔS or the accumulated reaction heat amount difference ΔJ during cooling after the completion, a more uniform heat treatment can be performed.
[0074]
【The invention's effect】
As described above, according to the present invention, since it is configured as described above, the following effects can be obtained.
[0075]
1) Claim 1, 5 According to the described invention, the temperature information at the time of heat treatment at a plurality of locations on the concentric circles of the measurement substrate is obtained in advance. Detected during the time from the start of the heat treatment of the measurement substrate until the heat treatment temperature becomes stable, and calculates the integrated heat amount between the temperature of the temperature information and the time until it stabilizes, and the obtained integrated heat amount Based on the above, find the difference in the accumulated heat amount of each of a plurality of locations, after the heat treatment temperature of the object to be processed in the heat treatment is stabilized, so as to cancel the difference in accumulated heat amount, Since each output amount of the heat source formed on the concentric circle of the mounting table is controlled, The amount of heat supplied to the object to be processed can be made equal in the plane, Heat treatment can be made uniform and yield can be improved.
[0076]
2) Claim 2 6 According to the described invention, Obtain the diffusion coefficient from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction in advance. Detect temperature information during heat treatment at multiple locations on the concentric circles of the workpiece, Calculate the total reaction heat from the diffusion coefficient and temperature information, In the surface of the workpiece during heat treatment Total reaction heat Since the output amounts of the plurality of heat sources formed on the concentric circles of the mounting table are controlled so as to be equal to each other, it is possible to directly control the thermal influence of the object to be processed. Therefore, it is possible to ensure uniform heat treatment in the surface of the object to be processed and improve yield.
[0078]
3 Claim 3 According to the described invention, a value obtained by integrating the product of the temperature of the object to be processed and the diffusion coefficient of the coating liquid applied to the object to be processed by the heat treatment time. (Integrated reaction heat) However, in addition to the above 1) and 2), in addition to the above 1) and 2), it directly contributes to the reaction of the coating liquid applied to the object to be processed. The amount of heat to be generated can be made equal in the plane, and the heat treatment of the object to be processed can be made more uniform.
[0079]
4 Claim 4,7 According to the described invention, the control of each output amount of the heat source is performed after the heat treatment temperature is stabilized in the surface of the workpiece. To offset the difference in total reaction heat So do the above 3) In addition to this, it is possible to control more accurately and to ensure uniform heat treatment.
[0080]
5 According to the eighth aspect of the invention, since the temperature detecting means is provided on the gap pin for supporting the object to be processed with a gap on the mounting table, the object to be processed by the temperature detecting means in addition to 2) above. The influence of heat on the surface of the substrate can be minimized, and the heat treatment of the object to be processed can be made uniform.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing an example of a resist solution coating / development processing system to which a heat treatment apparatus of the present invention is applied.
FIG. 2 is a schematic front view of the resist solution coating / developing system.
FIG. 3 is a schematic rear view of the resist solution coating / developing system.
FIG. 4 is a schematic sectional view showing an example of a heat treatment apparatus according to the present invention.
FIG. 5 is a schematic plan view showing an example of a heat treatment apparatus according to the present invention.
FIG. 6 is a schematic plan view showing the position of the temperature detecting means of the heat treatment apparatus according to the present invention.
FIG. 7 is an explanatory diagram showing the relationship between the heat treatment time when the object to be treated is heated, the temperature of the object to be treated, and the integrated heat quantity.
FIG. 8 is an explanatory diagram showing a relationship between an integrated temperature and an integrated heat amount when the object to be processed is heated.
FIG. 9 is an explanatory diagram showing an accumulated heat amount difference at an arbitrary position of the object to be processed;
FIG. 10 is an explanatory diagram showing a temperature of an object to be processed and a difference between accumulated heat amounts when the heat treatment method of the present invention is used.
FIG. 11 is an explanatory diagram showing the relationship between the temperature of the object to be processed and the diffusion coefficient of the coating liquid of the object to be processed.
FIG. 12 is an explanatory diagram showing the relationship between the accumulated reaction temperature and the accumulated reaction heat amount when the object to be treated is heat-treated.
FIG. 13 is an explanatory diagram showing an accumulated reaction calorific value difference at an arbitrary position of an object to be treated.
FIG. 14 is an explanatory diagram showing the temperature of an object to be processed and the difference in accumulated reaction heat when the heat treatment method of the present invention is used.
FIG. 15 is a schematic plan view showing an example of another heat treatment apparatus according to the present invention.
FIG. 16 is a schematic plan view showing the position of temperature detecting means of another heat treatment apparatus according to the present invention.
[Explanation of symbols]
W Semiconductor wafer (object to be processed)
DW dummy wafer (measurement substrate)
25 mounting table
26a-26g Heater (heat source)
58a-58g thermocouple (temperature detection means)
59 CPU (control means)
70 Gap pin

Claims (8)

In the heat treatment method of radiating heat from the surface of the mounting table on which the object to be processed is mounted and heat-treating the object to be processed,
Detects temperature information when the measurement substrate provided with temperature detection means at multiple locations on the concentric circles is pre-heated in the time from the start of the heat treatment of the measurement substrate until the heat treatment temperature stabilizes And storing in the control means for controlling the heat treatment,
While calculating the integrated heat amount between the temperature of the temperature information detected at each of the plurality of locations and the time until stabilization, the difference between the integrated heat amounts of the plurality of locations is calculated based on the calculated integrated heat amount. And a process for obtaining
After the heat treatment temperature of the object to be processed in the heat treatment is stabilized , each output amount of a plurality of heat sources formed on concentric circles of the mounting table is controlled so as to cancel the difference in the integrated heat amount. Heat treatment method. In the heat treatment method of radiating heat from the surface of the mounting table on which the object to be processed is mounted and heat-treating the object to be processed,
Obtaining the diffusion coefficient from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction in advance , detecting temperature information during heat treatment at a plurality of locations on the concentric circles of the object to be processed,
An integrated reaction heat amount is obtained from the diffusion coefficient and the temperature information , and each output amount of the heat source formed on a plurality of concentric circles on the mounting table is equalized so that the integrated reaction heat amount in the surface of the object to be treated during heat treatment becomes equal. The heat processing method characterized by controlling. The heat treatment method according to claim 2 , wherein
The heat treatment method , wherein the integrated reaction heat quantity is a value obtained by integrating the product of the temperature of the object to be processed and the diffusion coefficient of the coating liquid applied to the object to be processed with a heat treatment time. In the heat treatment method according to claim 2 or 3 ,
A heat treatment method characterized in that the control of each output amount of the heat source is performed so that the difference in accumulated reaction heat amount is canceled after the heat treatment temperature is stabilized in the plane of the object to be treated. In a heat treatment apparatus comprising a mounting table for mounting a target object, and radiating heat from the surface of the mounting table to heat-treat the target object,
A plurality of heat sources that are formed on concentric circles of the mounting table and supply heat to the mounting table;
A measurement substrate provided with temperature detection means at a plurality of locations on concentric circles;
Control means for detecting and storing temperature information when the measurement substrate is preliminarily heat-treated in a time from the start of the heat treatment of the measurement substrate to the stabilization of the heat treatment temperature;
The control means obtains an integrated heat amount between the temperature of the temperature information detected at each of a plurality of locations on the concentric circles and the time to stabilize, and based on the obtained integrated heat amount, Each of the heat sources formed in a plurality of concentric circles on the mounting table is determined so as to cancel the difference in the integrated heat amount after the heat treatment temperature of the object to be processed in the heat treatment is stabilized by obtaining a difference in the integrated heat amount at each location. A heat treatment apparatus characterized by controlling an output amount . In a heat treatment apparatus comprising a mounting table for mounting a target object, and radiating heat from the surface of the mounting table to heat-treat the target object,
A plurality of heat sources that are formed on concentric circles of the mounting table and supply heat to the mounting table;
Temperature detecting means for detecting temperatures at a plurality of locations on concentric circles of the object to be processed;
Control means for controlling each output amount of the heat source,
The control means obtains a diffusion coefficient in advance from the relationship between the temperature of the chemically amplified resist and the acid diffusion reaction, detects temperature information during heat treatment at a plurality of locations on concentric circles of the object to be processed, and performs the diffusion. The integrated reaction heat quantity is obtained from the coefficient and the temperature information, and the output amounts of a plurality of heat sources formed on the concentric circles of the mounting table are controlled so that the integrated reaction heat quantity in the surface of the object to be processed during heat treatment becomes equal. The heat processing apparatus characterized by the above-mentioned. The heat treatment apparatus according to claim 6, wherein
A heat treatment apparatus characterized in that the control of each output amount of the heat source by the control means is performed so that the difference in accumulated reaction heat amount is canceled after the heat treatment temperature is stabilized in the surface of the object to be treated. The heat treatment apparatus according to claim 6 or 7 ,
The temperature detection means is provided in a gap pin that supports the object to be processed with a gap on the mounting table.

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