JP3884173B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

【００５５】
となる。ただし、基板９の反射率をρとするとき、基板９が不透明であるという条件ε＋ρ＝１の関係を用いた。
【００５６】
数１の式より求めた基板の放射率εと多重反射効果による見かけの放射率εaとの関係を図８に反射面２１Ｅの反射率ｒごとに示す。
【００５７】
図８から反射面２１Ｅの反射率をより高くすることにより見かけの放射率εaが大きくなり、「１」に近づくことが分かる。
【００５８】
またここで注意したいのは反射面２１Ｅの反射率を高くすることにより、基板の放射率εの変化に対し、見かけの放射率εaの変化の割合が低くなっていることである。
【００５９】
図９および図１０は、それぞれ多重反射効果を用いない温度計測および多重反射効果を用いた温度計測における基板の放射率εと温度計測誤差の関係を示す図である。なお、図９および図１０における基板の温度は１０００℃とし、放射温度計の設定放射率はそれぞれ０．７および０．９５９と固定している。
【００６０】
放射率ε＝０．５の基板では、測定波長５μｍにおいて、多重反射効果を用いない場合は図９から測定誤差は約１６０℃であるのに対し、多重反射効果を用いた場合は図１０から約３０℃の測定誤差となる。しかしながら、多重反射効果を用いた場合でも、放射率ε＝０．３の基板では測定波長５μｍで約８５℃、０．９μｍで約２０℃の誤差を生してしまうことになる。
【００６１】
＜＜２−２．２つの放射温度計による温度計測＞＞
上述のように多重反射効果を用いることにより、基板の放射率の違いによる測定誤差を小さくすることはできるが、基板の温度計測としては不十分である。そこで、第１の実施の形態では２つの放射温度計による温度計測方法を用いている。
【００６２】
図１１は多重反射効果の度合いの違う光を取り込む２つの放射温度計による温度計測結果を示すグラフである。図１１においては、基板の放射率を固定（例えばε＝１．０）して温度計測を行っている。この場合、図１１に示すように多重反射効果が大きい放射温度計は、それの小さい放射温度計よりも高い温度を示す。すなわち両放射温度計による指示温度の相違Ｄが生じている。
【００６３】
第１の実施の形態では多重反射効果の度合いの異なる光を取り込む２つの放射温度計４ａ，４ｂを用いることによって、指示温度の違いに相当する放射エネルギー強度値の違いから、多重反射効果の大きい放射温度計単体で測定した場合（計測誤差ＥＲ）よりも正確（計測誤差が計測誤差ＥＲより小さい）に基板の温度を計測することができる。
【００６４】
＜＜２−３．２放射温度計方式の温度計測＞＞
前述の多重反射を用いた温度計測においては反射面２１Ｅの形状等により多重反射の度合いが異なる。そのため、数１の式における反射面２１Ｅの反射率ｒの代わりに、この多重反射の度合いを示すパラメータである実効反射率Ｒを用いると、数１の式は次式のようになる。
【００６５】
【数２】

【００６６】
ここでεaは見かけの放射率を表す。
【００６７】
つぎに、２つの放射温度計を用いた温度計測を行う場合を考える。この場合に、両放射温度計に対して、多重反射効果の大、小が意図的に設けられる。なお、第１の実施の形態では後述するように、２つの放射温度計はその視野角が互いに異なるような光学系を備えるものとされている。そしてその多重反射効果の大きい実効反射率をＲmain、小さい実効反射率をＲsubとする。
【００６８】
基板の放射率がεWの場合、各放射温度計に入射する放射エネルギー強度Ｉmain，Ｉsubは数２の式を用いて、
【００６９】
【数３】

【００７０】
【数４】

【００７１】
となる。ここでＩbは基板を黒体とみなした場合の放射エネルギー強度（以下「黒体放射エネルギー強度Ｉb」という）を表す。
【００７２】
数３および数４の式からεWを消去すると、
【００７３】
【数５】

【００７４】
となる。ここで、ＳはＲmainおよびＲsubにより表現することのできる定数で、２つの実効反射率の相対的な変化に基づく相対実効反射率を示す。
【００７５】
そして、基板の温度計測は以下のように行う。
【００７６】
まず、放射エネルギー強度Ｉmain，Ｉsubを各放射温度計の検出器４２２から出力される信号より算出する。そして、それら放射エネルギー強度Ｉmain，Ｉsubと、事前に求められた相対実効反射率Ｓを数５の式に用いて黒体放射エネルギー強度Ｉbを求める。
【００７７】
ところで、黒体の温度と黒体の放射エネルギー強度Ｉとの関係式であるプランクの輻射公式は、プランク定数をＣ1，Ｃ2、着目する波長をλ、温度をＴとするとき、次式で表される。
【００７８】
【数６】

【００７９】
この式を黒体の温度Ｔについての式に変形すると、
【００８０】
【数７】

【００８１】
となる。
【００８２】
ここで、数７の式は被計測物体が黒体である場合の式であるので、これをこのまま基板（放射率εが「１」以外）の温度計測に用いると計測誤差が大きくなる。そこで、基板温度ＴW、黒体放射エネルギー強度Ｉbを用いて数７の式を書き直すと、
【００８３】
【数８】

【００８４】
となる。ここで補正係数Ａは黒体放射エネルギー強度Ｉbから得られる基板温度ＴWが設定温度Ｔtc（すなわち、ＴW＝Ｔtc）となるようにするために上記プランク定数Ｃ２を補正した係数であり、検出器の感度や検出器までの光エネルギーのロスの度合いにより異なるものである。そして、数８の式により基板の温度ＴWが求められるのである。
【００８５】
＜＜２−４．基板の加熱処理手順＞＞
図１２は第１の実施の形態における基板処理の手順を示すフローチャートである。以上の温度計測原理に基づいて、実際の基板についてその温度を求めながらの加熱処理の手順は以下のようになる。
【００８６】
図示しない外部搬送装置により基板が基板処理装置１に搬入され（ステップＳ１)、支持リング７１１にセットされ、次いで、基板の加熱を開始する（ステップＳ２）。なお、基板の加熱とともに基板の回転が行われるとともに必要に応じてガス供給も行われる。
【００８７】
つぎに、基板の加熱を続けながら放射温度計４ａ，４ｂの出力信号により変換部５は放射エネルギー強度Ｉmain，Ｉsubを求める（ステップＳ３）。
【００８８】
また、変換部５は得られた放射エネルギー強度Ｉmain，Ｉsubおよび後述するようにして事前に求められた相対実効反射率Ｓを数５の式に用いて、基板を黒体とみなした場合の黒体放射エネルギー強度Ｉbを算出する（ステップＳ４）。
【００８９】
また、変換部５は後述するようにして事前に求められた補正係数Ａおよび得られた黒体放射エネルギー強度Ｉbを数８の式に代入することにより基板温度ＴWを求める（ステップＳ５）。
【００９０】
制御部６は得られた基板温度ＴWと予め設定していた設定温度Ｔtcとを比較し、ランプ３１に供給する電力のフィードバック制御を行う（ステップＳ６）。
【００９１】
そして、制御部６は処理時間の終了の判定を行い（ステップＳ７）、設定されていた処理時間が経過するまでステップＳ３〜ステップＳ７の処理を継続して行う。そして、処理時間が経過すると、外部搬送装置がその基板を搬出する（ステップＳ８）。
【００９２】
つぎに、制御部６は図示しない外部の基板給排機構からの信号により準備されていた全基板の加熱処理の終了の判定を行い（ステップＳ９）、全基板の加熱処理が終了していなければステップＳ１に戻り、外部搬送装置が次の基板を搬入し、逆に終了していれば一連の加熱を伴う基板処理を終了する。
【００９３】
以上で、１枚の基板の加熱処理が終了したことになるが、複数枚の基板を加熱処理する場合には、さらに、上記の基板加熱処理を各基板に対して繰り返し行う。
【００９４】
ところで、上述のように、この基板の温度計測には相対実効反射率Ｓおよび補正係数Ａを事前に求めておく必要がある。そのため、第１の実施の形態では実際の温度計測に先立って相対実効反射率Ｓの決定および補正係数Ａの決定による放射温度計の校正を行っている。以下、それらの決定方法について説明する。
【００９５】
＜＜２−５．相対実効反射率および補正係数の決定＞＞
第１の実施の形態における相対実効反射率Ｓおよび補正係数Ａの決定を以下のようにして行っている。すなわち、後に上記の処理手順により実際の基板処理が行われる基板と同種の複数種類の放射率が異なる基板であって、それぞれに熱電対が埋め込まれた基準基板を用意し、それを基板処理装置１により加熱する。そして、熱電対により計測される基準基板の温度が設定温度Ｔtcになった段階で、それぞれの基準基板について放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…を計測する。そして、これらの計測値を基に黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを求める。
【００９６】
図１３は放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…をもとに黒体放射エネルギー強度Ｉbを求める様子を表わしたグラフである。図１３では、Ｉmainを縦軸に、Ｉsubを横軸とした２次元平面内の点として放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…の計測値を表わしている。図中、同じ記号（丸や四角形等）で表わした点の組は同じ放射温度計４の設定のもとに連続して基板処理が行われる複数種類の基板と同種の基準基板に対する放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…の計測結果を示している。なお、１組のデータ（三角形）についてのみ参照符号を付した。
【００９７】
そして、第１の実施の形態では、放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…を平面に表わした場合に、各点との誤差が小さくなるように、例えば最小２乗法等によってこれら各点の近傍を通過する近似曲線ＡＬを求める。
【００９８】
ところで、数２の式においてε＝１とすると、見かけの放射率εaは実効反射率Ｒに依存しなくなることから、本来、黒体に対して放射エネルギー強度（Ｉmain，Ｉsub）を計測するとＩmain＝Ｉsubでなければならない。したがって、黒体放射エネルギー強度Ｉbは図１３のグラフにおいてＩmain＝Ｉsubの直線ＳＬ上に位置しているはずである。そのため黒体放射エネルギー強度Ｉbを求める際には、上記近似曲線ＡＬとＩmain＝Ｉsubの直線ＳＬとの交点のＩmain（またはＩsub）成分値を黒体放射エネルギー強度Ｉbとする。そして、このようにして得られた黒体放射エネルギー強度Ｉbと、得られた近似曲線上の任意の点（Ｉmain，Ｉsub）を数５の式に用いることにより、相対実効反射率Ｓを求める。
【００９９】
また、補正係数Ａを求める方法は以下の通りである。すなわち、得られた黒体放射エネルギー強度Ｉbおよび設定温度Ｔtcを、放射温度計の測定波長λとともに数８の式に代入する。ただし、設定温度Ｔtcは基板温度ＴWに代入する。これにより補正係数Ａが求まるのである。
【０１００】
このように、第１の実施の形態では補正係数Ａを求め、実際の基板処理においては、それを数８の式に用いて基板温度ＴWを求めるため、基板処理において数７の式によって得られた黒体放射エネルギー強度Ｉbを用いて基板の温度を求める場合に比べて、正確に基板の温度を求めることができる。
【０１０１】
また、以上の基板の温度計測および基準基板を用いた相対実効反射率Ｓおよび補正係数Ａの決定の処理において基板および基準基板の放射率を求めていない。このように第１の実施の形態では基板および基準基板の放射率を求める必要がない。
【０１０２】
以下、以上の方法による相対実効反射率Ｓおよび補正係数Ａの決定の処理手順について、それを示すフローチャートである図１４を用いて説明する。
【０１０３】
まず一の基準基板を作業者が支持リング７１１にセットし（ステップＳ１１）、基準基板の加熱を開始する（ステップＳ１２）。
【０１０４】
それとともに、制御部６は基準基板に埋め込まれた熱電対による温度信号を基に、設定温度Ｔtcに到達したかどうかの判定を行う（ステップＳ１３）。そして、設定温度Ｔtcに到達していなければ、熱電対により温度計測を行いながら加熱を続け、基準基板の温度が設定温度Ｔtcに到達するまで、繰り返しステップＳ１３の判定を行う。
【０１０５】
そして、基準基板の温度が設定温度Ｔtcに到達すると、制御部６の制御により変換部５は放射温度計４ａ，４ｂの出力信号に基づいて放射エネルギー強度（Ｉmain1，Ｉsub1）を求め（ステップＳ１４）、制御部６に送信する。
【０１０６】
つぎに、作業者がすべての基準基板について計測が終了したかどうかを判定する（ステップＳ１５）。そして、終了していなければ、作業者が基準基板を取り替え、他の基準基板を支持リング７１１にセットする。それに対してステップＳ１１〜Ｓ１３の処理を行い、設定温度Ｔtcに達した時、各放射温度計の出力信号から放射エネルギー強度（Ｉmain2，Ｉsub2），（Ｉmain3，Ｉsub3）…を求める。逆に終了していればステップＳ１６に進む。
【０１０７】
つぎに、作業者は得られた放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…をもとにＩmain−Ｉsub平面における近似曲線ＡＬを求め、その近似曲線ＡＬを基に上述の方法により、黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを算出し、それを図示しない入力手段を通じて変換部５に入力し、変換部５はそれを記憶する（ステップＳ１６）。
【０１０８】
最後に、作業者は得られた黒体放射エネルギー強度Ｉbおよび設定温度Ｔtcを、放射温度計４の測定波長λとともに数８の式に代入する（ただし、設定温度ＴtcはＴWに代入する）ことにより補正係数Ａを算出し、それを上記入力手段を通じて変換部５に入力し、変換部５はそれを記憶する（ステップＳ１７）。
【０１０９】
これで、相対実効反射率Ｓおよび補正係数Ａが求められた。これらを基に前述のようにして基板の温度管理を行いつつ基板処理を行うのである。
【０１１０】
以上説明したように、第１の実施の形態によれば、容器本体２１内部からの光の放射エネルギー強度Ｉmain，Ｉsubを計測し、それらに基づいて基板を黒体とみなした場合の黒体放射エネルギー強度Ｉbを算出し、その黒体放射エネルギー強度Ｉbに基づいて基板の温度を算出するため、接触式の温度計測手段による場合のように基板を汚染することなくその温度を計測して、より正確な温度管理が行うことができる。
【０１１１】
また、第１の実施の形態によれば複数の放射温度計４ａ，４ｂがそれぞれに入射する光の視野角が互いに異なる光学系４２１を有し、それらにより放射エネルギー強度Ｉmain，Ｉsubを計測し、それらに基づいて基板の温度を求めるため、大きな開口部を設けることなく、２種類の放射エネルギー強度を計測できるので基板の温度分布の均一性を損なうことなく、すなわち、基板の処理品質を悪化させることなく基板の温度を計測して正確な温度管理を行うことができる。
【０１１２】
また、第１の実施の形態によれば、複数の基準基板のそれぞれの放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…をもとに相対実効反射率Ｓを求め、それを用いて基板の温度を算出するため、１枚の基準基板のみによって相対実効反射率Ｓを求めて、基板の温度を算出する場合に比べて、より正確に基板の温度を算出することができ、より正確な基板の温度管理を行うことができる。
【０１１３】
また、互いに異なる複数種類の基板に対して基板処理を行う場合に、複数の基準基板がそれら複数種類の基板とそれぞれ同種のものであるため、実際の基板処理の際に用いる相対実効反射率Ｓをそれら複数種類の基板の温度計測にとって誤差の少ないものとすることができ、温度計測の精度を高めることができる。
【０１１４】
また、複数の基準基板のそれぞれに対して求められた放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…をＩmain−Ｉsub平面内の点として表した場合の各点に対して誤差が少ない近似曲線を求め、その近似曲線に基づいて相対実効反射率Ｓを求めるため、より誤差の少ない相対実効反射率Ｓを求めることができ、一層、温度計測の精度を高めることができる。
【０１１５】
さらに、第１の実施の形態によれば、補正係数Ａを求め、得られた補正係数Ａを用いて基板の温度を算出するため、基準基板や基板の正確な放射率を求めなくとも基板の温度を正確に求めることができる。
【０１１６】
＜３．第２の実施の形態の温度計測原理＞
上記第１の実施の形態の基板処理においては、数８の式を用いて基板温度ＴWを正確に求めたが、放射温度計の校正が既に行われているか、温度計測の精度がさほど要求されず放射温度計の校正が不要な場合には、数８の式の代わりに数７の式の黒体の放射エネルギー強度Ｉに数５の式に予め求めた相対実効反射率Ｓで得られる放射エネルギー強度Ｉbを代入することによって、得られる黒体の温度Ｔを基板温度ＴWとみなすことができる。
【０１１７】
そして、この場合にも基板処理手順は図１４に示したものと同様である。ただし、この場合には放射温度計の校正を行わない。すなわち、第２の実施の形態における温度計測では数８の式を用いないため、その式における補正係数Ａを求める必要がない。そのため、この第２の実施の形態では熱電対を埋め込んだ基準基板を１枚のみ用い、それにより相対実効反射率Ｓの決定処理のみを行っている。
【０１１８】
図１５は第２の実施の形態における相対実効反射率Ｓの決定処理手順を示すフローチャートである。以下、図１５に基づいてこの処理手順およびその原理を説明していく。
【０１１９】
この処理でもステップＳ２１〜Ｓ２４の処理は図１４のステップＳ１１〜１４の処理と同様であるので説明を省略する。
【０１２０】
つぎに、作業者は設定温度Ｔtcおよび得られた放射エネルギー強度（Ｉmain，Ｉsub）を基に黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを算出し、それを上記入力手段を通じて変換部５に入力し、変換部５はそれを記憶する（ステップＳ２５）。具体的には、まず、設定温度Ｔtcを黒体の温度Ｔとみなして数６の式に用いて黒体放射エネルギー強度Ｉbを求める。つぎに、計測した放射エネルギー強度（Ｉmain，Ｉsub）および得られた黒体放射エネルギー強度Ｉbを数５の式に用いることにより相対実効反射率Ｓを求めるのである。
【０１２１】
これで、相対実効反射率Ｓが求められた。これを基に前述のようにして基板の温度管理を行いつつ基板処理を行うのである。
【０１２２】
以上説明したように、第２の実施の形態によれば、第１の実施の形態における複数の基準基板を用いたことによる効果および補正係数Ａを用いたことによる効果以外の効果と同様の効果を有している。
【０１２３】
＜４．変形例＞
上記第１および第２の実施の形態において基板処理装置およびそれによる基板処理方法の例を示したが、この発明はこれに限られるものではない。
【０１２４】
たとえば、上記実施の形態では、放射温度計４ａ，４ｂを１組のみ備えるものとしたが、軸２１Ｃからの距離が異なる位置に複数組の放射温度計４ａ，４ｂを設けて、基板の各部分での温度計測および温度管理を行うものとしてもよい。また、放射温度計４の光学系を変倍可能なものとしてレンズを光軸方向に移動させることができるものを１つ設けて、放射温度計４ａと４ｂの２つの状態を切り替えられるものとしてもよい。
【０１２５】
また、上記実施の形態では、基板処理装置１ではランプ３１からの光を石英窓２２を介して基板９に照射するようになっているが、加熱手段はランプに限定されるものではなく、ヒータ等であってもよい。
【０１２６】
また、微小開口部２１Ｈは基板の温度の均一性が損なわれずに温度測定ができるのであるならばどのような大きさであってもよい。なお、このような条件を十分に満たす微小開口部２１Ｈの大きさとしては直径１〜３ｍｍが好ましい。
【０１２７】
また、上記実施の形態ではサーモパイル４２２ａを利用した放射温度計４により温度測定を行っているが、微小開口部２１Ｈからの光を利用して温度測定を行うことができるのであれば他の温度計であってもこの発明を利用することができる。
【０１２８】
また、上記実施の形態では微小開口部２１Ｈと検出器４２２とがほぼ光学的に共役な関係に配置されると説明したが、これは微小開口部２１Ｈからの光を検出器４２２が検出して温度測定を行うことができる程度に検出器４２２上に光が集められるという配置関係をいう。
【０１２９】
また、検出用窓部材４１１が汚れない処理環境にて基板９の処理が行われる場合には微小開口部２１Ｈへのガス供給のための構成は設けなくてもよい。
【０１３０】
また、上記実施の形態では光学系４２１の光軸４Ｊが基板９の面に垂直であると説明したが、これに限定されるものではない。
【０１３１】
また、上記実施の形態では光学系４２１はレンズを利用しているが反射鏡を利用してもよい。
【０１３２】
また、上記実施の形態では相対実効反射率Ｓ等を求める際には基準基板が設定温度Ｔtcに達した時に放射エネルギー強度を計測し、それを基に相対実効反射率Ｓ等を求めたが、多少の精度の悪化が問題にならないような場合には基準基板がその他の温度にある状態での放射エネルギー強度を求めてもよい。この場合には、熱電対によって計測した温度値を用いて相対実効反射率Ｓ等を求めればよい。
【０１３３】
また、上記第１の実施の形態では、相対実効反射率Ｓを求める際に放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…に対して近似曲線を求めて、その近似曲線に基づいて黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを求めたが、数５の式において、黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓをパラメータとして、計測された放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…を用い、最小２乗法等の近似方法によって黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを求めてもよい。なお、２枚の基準基板により放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）を計測した場合には、数５の式に放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）の計測値を代入して得られた連立方程式を解いて、黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを求めてもよい。これは数５の式に放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）を用いて最小２乗法を行うことと等価になる。
【０１３４】
また、上記第１の実施の形態では基板処理を行う基板の種類のそれぞれと同じ種類の基準基板について放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…を計測し、それらについて近似曲線を求めるものとしたが、実際に基板処理を行う基板と異なる種類の複数の基準基板について、放射エネルギー強度を計測して、近似曲線を求めてもよい。さらに、予め代表的な基板に対して計測した放射エネルギー強度（Ｉmain1，Ｉsub1），（Ｉmain2，Ｉsub2）…を記憶してデータベース化しておき、基板処理の前に読み出して利用し、同様の方法により黒体放射エネルギー強度Ｉbおよび相対実効反射率Ｓを算出するものとしてもよい。
【０１３５】
【発明の効果】
以上説明したように、請求項１ないし請求項６の発明によれば、基板側からの反射面における開口部を介した放射エネルギー強度を計測し、その放射エネルギー強度に基づいて基板を黒体とみなした場合の黒体放射エネルギー強度を算出し、その黒体放射エネルギー強度に基づいて基板の温度を算出するため、接触式の温度計測手段による場合のように基板を汚染することなくその温度を計測して、より正確な温度管理が行うことができる。
【０１３６】
また、複数の強度計測手段がそれぞれに入射する放射エネルギーの視野角が互いに異なる光学系を有し、それらにより放射エネルギー強度を計測し、それらに基づいて基板の温度を求めるため、大きな開口部を設けることなく、２種類の放射エネルギー強度を計測できるので基板の温度分布の均一性を損なうことなく、すなわち、基板の処理品質を悪化させることなく基板の温度を計測して正確な温度管理を行うことができる。
【０１３７】
また、請求項３の発明によれば、複数の基準基板のそれぞれの放射エネルギー強度をもとに相対実効反射率を求め、それを用いて基板の温度を算出するため、１枚の基準基板のみによって相対実効反射率を求めて基板の温度を算出する場合に比べて、より正確に基板の温度を算出することができ、より正確な基板の温度管理を行うことができる。
【０１３８】
また、請求項４の発明によれば、強度計測工程、強度算出工程および温度算出工程を互いに異なる複数種類の基板に対して行うものであり、複数の基準基板がそれら複数種類の基板とそれぞれ同種のものであるため、実際の基板処理の際に用いる相対実効反射率をそれら複数種類の基板の温度計測にとって誤差の少ないものとすることができ、温度計測の精度を高めることができる。
【０１３９】
また、請求項５の発明によれば、複数の基準基板のそれぞれに対して求められた第１放射エネルギー強度Ｉmainおよび第２放射エネルギー強度Ｉsubの組をＩmain−Ｉsub平面内の点として表した場合の各点に対して誤差が少ない近似曲線を求め、その近似曲線に基づいて相対実効反射率を求めるため、より誤差の少ない相対実効反射率を求めることができ、一層、温度計測の精度を高めることができる。
【０１４０】
さらに、請求項６の発明によれば、プランク定数を補正した補正係数を求め、得られた補正係数を用いて基板の温度を算出するため、基準基板や基板の正確な放射率を求めることなく基板の温度を正確に求めることができる。
【図面の簡単な説明】
【図１】この発明の一の実施の形態である基板処理装置の縦断面図である。
【図２】図１に示す基板処理装置の底面図である。
【図３】容器本体部に取り付けられた一の放射温度計の縦断面図である。
【図４】容器本体部に取り付けられた他の放射温度計の縦断面図である。
【図５】フランジ部およびガス供給管を示す上面図である。
【図６】微小開口部近傍の部分拡大図である。
【図７】基板の下面と反射面との間の多重反射を説明するための図である。
【図８】基板の放射率と多重反射効果による見かけの放射率との関係示す図である。
【図９】多重反射効果を用いない温度計測での基板の放射率と温度計測誤差の関係を示す図である。
【図１０】多重反射効果を用いた温度計測での基板の放射率と温度計測誤差の関係を示す図である。
【図１１】多重反射効果の度合いの違う光による温度計測結果を示すグラフである。
【図１２】第１の実施の形態における基板処理の手順を示すフローチャートである。
【図１３】第１の実施の形態における黒体放射エネルギー強度を求める様子を示すグラフである。
【図１４】相対実効反射率および補正係数の決定処理手順を示すフローチャートである。
【図１５】第２の実施の形態における相対実効反射率の決定処理手順を示すフローチャートである。
【符号の説明】
１ 基板処理装置
２ チャンバ
４Ｌ 光
４ａ，４ｂ 放射温度計（５と併せて強度計測手段）
５ 変換部（強度算出手段、温度算出手段）
６ 制御部
９ 基板
２１Ｅ 反射面
２１Ｈ 微小開口部
３１ ランプ（加熱手段）
４２１ 光学系
４２２ 検出器
Ａ 補正係数
Ｉb 黒体放射エネルギー強度
Ｉmain，Ｉsub 放射エネルギー強度
Ｓ 相対実効反射率
ＶＡ１，ＶＡ２ 視野角[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus and a substrate processing method for subjecting a substrate such as a semiconductor wafer, a glass substrate for a photomask, a glass substrate for liquid crystal display, and an optical disk substrate (hereinafter simply referred to as “substrate”) to heat treatment. .
[0002]
[Prior art]
In manufacturing a semiconductor device, various processes are performed on a substrate. Among these processes, there is a process of heating the substrate in a predetermined atmosphere (including vacuum) for the purpose of forming an oxide film, a nitride film, or the like on the substrate or performing an annealing process. Further, in such a process involving heating of the substrate, appropriate temperature management is required in order to keep the quality of the semiconductor device constant.
[0003]
As a substrate processing method with such temperature management, there is a method of performing substrate processing while performing so-called contact-type temperature measurement, such as attaching a temperature measuring means such as a thermocouple to the substrate and measuring the substrate temperature by that. Are known.
[0004]
[Problems to be solved by the invention]
By the way, in the above contact-type temperature measuring method, since the temperature measuring means is directly attached to the substrate, contaminants are likely to adhere to the substrate, resulting in deterioration of the quality of the substrate.
[0005]
The present invention is intended to overcome the above-mentioned problems in the prior art, and provides a substrate processing apparatus and a substrate processing method capable of measuring the temperature of the substrate without contaminating it and performing more accurate temperature management. Objective.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an apparatus according to a first aspect of the present invention is a substrate processing apparatus for performing a process involving heating on a substrate, the heating means for heating one surface of the substrate, and an opening portion. The intensity of the radiant energy is measured by detecting the radiant energy from the reflecting surface that is formed and facing the other surface of the substrate and the radiant energy from the substrate side through the opening. plural Intensity measuring means, intensity calculating means for calculating a black body radiant energy intensity when the substrate is regarded as a black body based on the radiant energy intensity measured by the intensity measuring means, and black body radiation calculated by the intensity calculating means Temperature calculating means for calculating the temperature of the substrate based on the energy intensity. The plurality of intensity measuring means includes optical systems having different viewing angles of incident radiant energy, and the intensity calculating means includes the plurality of radiant energies measured by the plurality of intensity measuring means. The black body radiant energy intensity is calculated based on the intensity. .
[0008]
Further, the claims of the present invention 2 The method described in (1) detects a heating means for heating one surface of a substrate, a reflective surface facing the other surface of the substrate while an opening is formed, and detecting radiant energy from the substrate through the opening. A substrate processing method using a substrate processing apparatus comprising an intensity measuring means for measuring radiant energy intensity by detecting with a measuring device, an intensity measuring step for measuring the radiant energy intensity by the intensity measuring means, and an intensity measurement An intensity calculation step for calculating the black body radiant energy intensity when the substrate is regarded as a black body based on the radiant energy intensity measured in the process, and a substrate based on the black body radiant energy intensity calculated in the intensity calculation step. A temperature calculation step for calculating temperature In the intensity measurement step, a plurality of radiant energy intensities incident through optical systems having different viewing angles are measured, and in the intensity calculation step, a plurality of the radiations measured in the intensity measurement step are measured. The black body radiant energy intensity is calculated based on the energy intensity. .
[0009]
Further, the claims of the present invention 3 The method described in claim 2 The substrate processing method according to claim 1, wherein, before each of the steps, the plurality of reference substrates having different emissivities are heated by the substrate processing apparatus, and the radiant energy of each of the plurality of reference substrates is measured by the intensity measurement unit. A reference intensity measuring step for measuring the intensity, and a reflectance calculating step for calculating a relative effective reflectance based on the radiant energy intensity of a plurality of reference substrates obtained in the reference intensity measuring step, and in the temperature calculating step The substrate temperature is calculated using the relative effective reflectance value calculated in the reflectance calculation step.
[0010]
Further, the claims of the present invention 4 The method described in claim 3 The substrate processing method according to claim 1, wherein the strength measurement step, the strength calculation step, and the temperature calculation step are performed on a plurality of different types of substrates, and the plurality of reference substrates are the same type as the plurality of types of substrates, respectively. It is characterized by being.
[0011]
Further, the claims of the present invention 5 The method described in claim 3 Or claims 4 The substrate processing method according to claim 1, wherein the reference intensity measurement step measures the first radiant energy intensity Imain and the second radiant energy intensity Isub by radiant intensity measuring means having two different viewing angles, and the reflectance There is an error with respect to each point when the calculation step represents the set of the first radiant energy intensity Imain and the second radiant energy intensity Isub obtained for each of the plurality of reference substrates as a point in the Imain-Isub plane. A reference black body that calculates a component value at any of intersections of the approximate curve in the Imain-Isub plane and the straight line Imain = Isub as a reference blackbody radiant energy intensity for a plurality of reference boards Imain and Isub component values at arbitrary points on the approximate curve obtained in the intensity calculation step, the curve calculation step, and the reference blackbody intensity calculation step Characterized in that from the reference black body radiation energy intensity in which and a step of calculating the relative effective reflectivity.
[0012]
Further claims of the invention 6 The method described in claim 3 Or claims 5 The substrate processing method according to any one of the above, further comprising a reference black body intensity calculating step of calculating a black body radiant energy intensity based on each of the radiant energy intensities of the plurality of reference substrates obtained in the reference intensity measuring step And a coefficient calculating step for obtaining a correction coefficient by correcting the Planck constant in the Planck radiation formula based on the black body radiant energy intensity obtained in the reference black body intensity calculating step, and the temperature calculating step in the coefficient calculating step The temperature of the substrate is calculated using the obtained correction coefficient.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
<1. Device configuration>
<< 1-1. Overall configuration >>
FIG. 1 is a longitudinal sectional view showing a configuration of a substrate processing apparatus 1 according to an embodiment of the present invention, and FIG. 2 shows a state when the substrate processing apparatus 1 shown in FIG. 1 is viewed from an arrow Z direction (downward). FIG. Note that the drawings (including FIGS. 1 and 2) referred to in the following description include a cross-sectional display that is not provided with parallel diagonal lines, and the details of the shape are simplified as appropriate.
[0015]
The substrate processing apparatus 1 includes a chamber 2 that is a container that accommodates a substrate 9, a lamp 31 that emits light for heating the substrate 9, and a radiation thermometer 4 that measures the temperature of the substrate 9 in a predetermined atmosphere. By irradiating the upper surface of the substrate 9 with light from the lamp 31, the substrate 9 is subjected to a process involving heating, and the temperature of the substrate 9 is measured and managed by the radiation thermometer 4. The radiation thermometer 4 is connected to the conversion unit 5. The conversion unit 5 includes a CPU, a memory, and the like (not shown), generates data such as radiant energy intensity from a signal from the radiation thermometer 4, and further obtains the temperature of the substrate 9 based on the data. ing. A control unit 6 is connected to the conversion unit 5, and the control unit 6 is connected to a lamp control unit 32, a motor 725, a gas supply unit (not shown), and the like (not shown), which will be described later, and controls them.
[0016]
Further, the lamp 31 is covered with a lid portion 61 and is controlled to be lit by a lamp control unit 32. Further, a support portion 71 that supports the substrate 9 is provided inside the container main body portion 21, a lift portion 8 that raises and lowers the substrate 9 at the lower portion of the container main body portion 21, and the substrate 9 is rotated inside the chamber 2. A rotation driving unit 72 is provided.
[0017]
Hereinafter, these configurations will be described in order and the internal structure of the radiation thermometer 4 will be described.
[0018]
The lamp 31 is provided so that a plurality of rod-shaped lamps are covered with the lid 61 outside the chamber 2, and the lamp 31 is controlled to be lighted by supplying power from the lamp controller 32. Further, the lid 61 has a cooling water channel 611 formed therein so as not to be heated by the light from the lamp 31, and further, the light from the lamp 31 is reflected to efficiently heat the substrate 9. The inner wall is processed into a mirror surface so that it can be done.
[0019]
The chamber 2 is configured by attaching a quartz window 22 covering the upper side of the substrate 9 to a container main body 21 that covers the lower side and the side periphery of the substrate 9. The quartz window 22 is made of quartz, and is positioned between the substrate 9 placed in the chamber 2 and the lamp 31 and serves as a window that transmits light from the lamp 31. The container main body 21 is provided with a carry-in / out opening 21A for carrying in / out the substrate 9, and a door 23 is provided at the carry-in / out opening so as to be opened and closed. Further, the container body 21 is provided with a supply port 21B for supplying various gases such as nitrogen dioxide (NO2) and ammonia (NH3) into the chamber 2 and an exhaust port 21D for exhausting the gas in the chamber 2. .
[0020]
A cooling water channel 211 is formed in the container body 21 as well as the lid 61, and the inside of the container body 21 is processed so that light can be reflected and the substrate 9 can be efficiently heated. ing.
[0021]
Next, a configuration for rotating the substrate 9 while supporting the substrate 9 inside the chamber 2 will be described.
[0022]
A support portion 71 for supporting the substrate 9 is provided inside the container body portion 21, and the support portion 71 is configured such that a support ring 711 that supports the outer periphery of the substrate 9 is supported by the support pillar 712. The support ring 711 is mainly formed of silicon carbide (SiC), and also serves to make the temperature distribution of the substrate 9 uniform. The support pillar 712 is made of quartz.
[0023]
The support portion 71 is driven by a rotation drive portion 72 and performs a rotational motion around an axis 21 </ b> C that is the center of the substrate 9 to be supported. Thereby, the substrate 9 being processed is rotated along the outer periphery.
[0024]
The rotation drive unit 72 is provided in the lower part of the container body 21, and is connected to the support unit 71 to be disposed in the chamber 2, the magnet 721 disposed outside the chamber 2, and the magnets 721 and 722. Bearings 723 and 724 for guiding the motors around the shaft 21C, and a motor 725 serving as a driving source for moving the magnet 722 outside the chamber 2. Further, a plurality of magnets 721 and magnets 722 are arranged on a circumference centering on the shaft 21 </ b> C so as to sandwich a part of the container body 21 from inside and outside of the chamber 2, and bearings 723 and 724. Is a circle centered on the shaft 21C. In addition, illustration of these structures is abbreviate | omitted in FIG.
[0025]
When the motor 725 is driven, the magnet 722 rotates about the shaft 21C, and the magnet 721 in the chamber 2 that interacts with the magnet 722 also rotates about the shaft 21C. The magnet 722 is connected to the support column 712. When the magnet 722 rotates about the shaft 21C, the support column 712 and the support ring 711 rotate about the shaft 21C. Thereby, the board | substrate 9 is rotated along an outer periphery.
[0026]
Next, the structure of the lift part 8 that raises and lowers the substrate 9 will be described, and the operation of carrying the substrate 9 in and out of the chamber 2 will be described.
[0027]
Three lift parts 8 for raising and lowering the substrate 9 are provided on the lower part of the container main body part 21 on the circumference around the shaft 21C as shown in FIG. As shown in FIG. 1, the lift portion 8 has lift pins 81 that move up and down. When the lift pins 81 are raised, the substrate 9 is lifted from the support ring 711. In the carrying-in operation, first, the lift pins 81 rise and stand by, and the substrate 9 is lowered from the outside of the substrate processing apparatus 1 so that the substrate 9 is placed on the lift pins 81 and the hands 91 are retracted to the outside of the chamber 2. Thereafter, the lift pins 81 are lowered to place the substrate 9 on the support ring 711. Further, when the substrate 9 is carried out of the chamber 2, an operation opposite to the carrying-in operation is performed.
[0028]
<< 1-2. Configuration of radiation thermometer >>
Next, the configuration of the radiation thermometer 4 that measures the temperature of the substrate 9 will be described in detail.
[0029]
In the substrate processing apparatus 1, as shown in FIG. 2, two radiation thermometers 4 (labeled as radiation thermometers 4a and 4b, respectively, are necessary in the following description) at substantially the same distance (r1 = r2) from the shaft 21C. Is called). And each radiation thermometer 4a and 4b is located so that the center angle which the straight line which connects each and the axis | shaft 21C makes may become a substantially right angle.
[0030]
Two large and small circles indicated by a two-dot chain line in FIG. 2 indicate the sizes of the large substrate 9 and the small substrate 9, and this apparatus is for these two types of substrates 9. It is an apparatus that can perform processing.
[0031]
As described above, since the radiation thermometers 4a and 4b are provided at substantially the same distance from the shaft 21C, the radiation energy of multiple reflections in substantially the same region of the substrate 9 by the timing control by the control unit 6 accompanying the rotation of the substrate 9. The intensity can be measured. As will be described later, the temperature of the substrate 9 can be measured based on this radiant energy intensity.
[0032]
Further, when the processing of the small substrate 9 is performed, the support ring 711 shown in FIG. 1 can be replaced with a small one.
[0033]
3 and 4 are longitudinal sectional views showing the radiation thermometer 4 attached to the lower part of the container main body 21, and particularly FIG. 3 shows the radiation thermometer 4a and FIG. 4 shows the radiation thermometer 4b. The radiation thermometer 4 has a flange portion 41 attached to the container main body portion 21, a holder 42 attached to the flange portion 41, and a cover 43 attached to the flange portion 41 and surrounding the holder 42. A detection window member 411 held by the flange portion 41, a gas supply pipe 44 attached to the flange portion 41, and an optical system 421 and a detector 422 held by the holder 42. The detector 422 is connected to the conversion unit 5 and receives the signal from the detector 422, and the conversion unit 5 obtains the temperature of the substrate 9 by a method described later.
[0034]
FIG. 5 is a view showing a state in which the flange portion 41 and the gas supply pipe 44 are viewed from above (in the direction of arrow AA in FIGS. 3 and 4). As shown in FIG. 5, the flange portion 41 has a flange shape having two attachment holes 41 </ b> A, and the radiation thermometer 4 is attached to the lower outer wall of the container main body portion 21 through the attachment holes 41 </ b> A.
[0035]
FIG. 6 is a partially enlarged view of FIGS. 3 to 5 and will be referred to as appropriate in the following description.
[0036]
As shown in FIG. 3, the surface of the flange portion 41 attached to the container main body portion 21 has a convex portion 41 </ b> F (referenced in FIGS. 5 and 6) that protrudes toward the container main body portion 21. The flange portion 41 is attached to the container main body 21 so that the portion 41F and the concave portion 21F of the container main body portion 21 fit together. The container body 21 is formed with a minute opening 21H that is a minute opening penetrating the container body 21 at the center of the recess 21F, and the light inside the chamber 2 is transmitted through the minute opening 21H to the radiation thermometer. Led to 4. That is, in the chamber 2, a minute opening 21 </ b> H is formed at a position facing the lower surface of the substrate 9.
[0037]
As shown in FIG. 6, a detection hole 41 </ b> H for introducing light from the minute opening 21 </ b> H is formed at the tip of the convex portion 41 </ b> F of the flange portion 41 to isolate the inside of the chamber 2 from the inside of the radiation thermometer 4. Therefore, a detection window member 411 in contact with the detection hole 41H is arranged inside the convex portion 41F. The detection hole 41H is an opening that is equal to or smaller than the minute opening 21H. With such a configuration, when the radiation thermometer 4 is attached to the container main body 21, the detection window member 411 is positioned at the minute opening 21H. As shown in FIG. 3, the detection window member 411 is fixed by the fixing member 413 through the O-ring 412 so as to be urged from the inside of the flange portion 41 toward the detection hole 41H, and the detection hole 41H. Is sealed.
[0038]
The holder 42 fixed to the flange portion 41 holds the optical system 421 and the detector 422 in order from the detection window member 411 side, and the optical system 421 has two lenses 421a and 421b. Further, by adjusting the position of the holder 42 with respect to the flange portion 41 with respect to the direction toward the detection hole 41H, the minute opening 21H and the detector 422 are arranged in an optically conjugate relationship with respect to the optical system 421. Yes. Thereby, the light incident on the radiation thermometer 4 from the inside of the chamber 2 through the minute opening 21H is guided to be collected on the detector 422 through the detection hole 41H and the optical system 421. In this radiation thermometer 4, the optical axis 4J (shown in FIG. 6) of the optical system 421 faces the Z direction (direction perpendicular to the substrate 9).
[0039]
The minute opening 21H is a hole having a taper that gradually expands toward the inside of the chamber 2. As shown by the broken line arrow in FIG. 6, the light 4L inclined with respect to the optical axis 4J from the inside of the chamber 2 is sufficiently incident on the optical system 421 so that the viewing angle of the radiation thermometer 4 is sufficiently secured. It is to do.
[0040]
The detector 422 has a thermopile (a plurality of thermocouples) 422a at a position where light is guided, and has a diaphragm plate 422b in the vicinity of the thermopile 422a in order to limit the amount of light incident on the detector 422. is doing.
[0041]
As shown in FIGS. 3 and 4, lenses 421a and 421b (see FIG. 3) provided in the optical system 421 of the radiation thermometer 4a and lenses 421a and 421b (see FIG. 4) provided in the optical system 421 of the radiation thermometer 4b. ) Are different, and furthermore, they are attached to the holder 42 at different positions in the direction of the optical axis 4J. As a result, the viewing angle VA1 (see FIG. 3) of the radiation thermometer 4a and the viewing angle VA2 (see FIG. 4) of the radiation thermometer 4b are different from each other (VA1 <VA2). Thereby, as described later, the degree (number of times) of multiple reflections of the heat radiation light incident on the minute openings 21H are different from each other.
[0042]
As described above, the manner in which the radiation thermometer 4 is attached to the container main body 21 and the configuration for guiding light to the detector 422 inside the radiation thermometer 4 have been described. Since the opening 21H and the optical system 421 are arranged in an almost optically conjugate relationship, light that passes through the minute opening 21H from the inside of the chamber 2 and enters the radiation thermometer 4 is collected by the detector 422. . Therefore, accurate temperature measurement by the detector 422 is possible only by forming the minute opening 21H in the container main body 21 which is a part of the chamber 2. As a result, it is not necessary to provide the chamber with a large opening leading to the detector 422, and the uniformity of the temperature distribution of the substrate 9 is not impaired.
[0043]
In addition, the measurement availability in the low temperature range depends on the measurement wavelength, and the light guide rod or Optical fiber However, when a light guide tube or the like is used, the wavelength range is limited, and thus the low temperature range cannot be measured. However, in the present invention, since the optical system 421 is used, light is collected in the detector 422. It is not attenuated while light is guided to the detector as in the case of using an optical rod, an optical fiber, a light guide tube or the like. 9 temperature measurements are also possible.
[0044]
In the substrate processing apparatus 1, since the container main body 21 and the inside of the radiation thermometer 4 are separated by the detection window member 411, there is no space in which the gas inside the chamber 2 stays. Therefore, the efficiency of gas replacement inside the chamber 2 is not impaired.
[0045]
<< 1-3. Use of multiple reflection effect >>
The radiation thermometer 4 of the substrate processing apparatus 1 can use the multiple reflected light for temperature measurement.
[0046]
FIG. 7 is a view for explaining multiple reflection between the lower surface of the substrate 9 and the reflecting surface 21E. Multiple reflection means that light radiated from the substrate 9 heated to high temperature by the light from the lamp 31 is reflected a plurality of times between the reflecting surface 21E, which is the bottom surface inside the container main body 21, and the lower surface of the substrate 9. Multiple reflected light (hereinafter referred to as “multiple reflected light”) can be used for temperature measurement based on the same principle as cavity radiation. Therefore, by using light that contains a large amount of multiple reflected light for temperature measurement, temperature measurement that is not easily affected by the surface state of the substrate 9 can be performed.
[0047]
In order to make a large amount of multiple reflected light incident on the radiation thermometer 4, the optical axis 4J of the radiation thermometer 4 (however, the optical axis 4J is parallel to the Z direction and is supported by the lower surface of the substrate 9 and the inside of the container main body 21). The bottom surface is substantially perpendicular to the Z direction). The light parallel to the Z direction is light that cannot reach the minute opening 21H even if it is reflected many times between the substrate 9 and the bottom surface of the container main body 21, or does not undergo multiple reflection from the substrate 9. This is because the light is incident on the minute opening 21H. Conversely, the light incident on the minute opening 21H with an inclination with respect to the Z direction is reflected many times between the substrate 9 and the bottom surface of the container main body 21 and has a large amount of light components that reach the minute opening 21H. include.
[0048]
In the radiation thermometer 4, a light shielding part 421c is formed on the surface of the lens 421a on the detection window member 411 side as shown in FIG. The light shielding part 421c is formed of gold deposited in a circle around the optical axis 4J of the lens 421a, and shields the central part of the lens 421a. Therefore, of the light incident on the radiation thermometer 4, the component incident in parallel with the Z direction is substantially shielded by the light shielding portion 421 c and cannot reach the detector 422. As a result, only the light 4L inclined with respect to the Z direction enters the detector 422. That is, the light shielding part 421c has a function of extracting a component that is not parallel to the optical axis 4J from the light incident on the minute opening 21H.
[0049]
As described above, the radiation thermometer 4 uses light containing a large amount of multiple reflected light as detection light for temperature measurement, thereby realizing temperature measurement that is not easily affected by the surface state of the lower surface of the substrate 9.
[0050]
As is clear from FIG. 6, the light 4L is incident as the minute opening 21H is reduced or the diameters of the lens 421a and the light shielding part 421c are increased, and the effect of multiple reflection is obtained. Can be obtained.
[0051]
<2. Temperature Measurement Principle and Processing Procedure of First Embodiment>
<< 2-1. Temperature measurement using multiple reflections >>
As a temperature measurement method that reduces errors due to mistakes in emissivity setting, there is a temperature measurement using multiple reflection. Hereinafter, this method will be described.
[0052]
As described above with reference to FIG. 7, multiple reflection occurs between the lower surface of the substrate 9 and the reflecting surface 21E.
[0053]
If the reflectivity of the reflector is r and the emissivity of the substrate is ε, the light intensity at each reflection stage of multiple reflection is as shown in FIG. 7, so the apparent emissivity εa is
[0054]
[Expression 1]

[0055]
It becomes. However, when the reflectance of the substrate 9 is ρ, the relationship of ε + ρ = 1 that the substrate 9 is opaque is used.
[0056]
FIG. 8 shows the relationship between the substrate emissivity ε obtained from the equation (1) and the apparent emissivity εa due to the multiple reflection effect for each reflectivity r of the reflecting surface 21E.
[0057]
It can be seen from FIG. 8 that the apparent emissivity εa increases by increasing the reflectivity of the reflecting surface 21E and approaches “1”.
[0058]
It should also be noted here that the rate of change in the apparent emissivity εa is reduced with respect to the change in the emissivity εa of the substrate by increasing the reflectivity of the reflecting surface 21E.
[0059]
FIGS. 9 and 10 are diagrams showing the relationship between the substrate emissivity ε and the temperature measurement error in the temperature measurement not using the multiple reflection effect and the temperature measurement using the multiple reflection effect, respectively. The temperature of the substrate in FIGS. 9 and 10 is 1000 ° C., and the set emissivity of the radiation thermometer is fixed at 0.7 and 0.959, respectively.
[0060]
For a substrate with an emissivity ε = 0.5, the measurement error is about 160 ° C. from FIG. 9 when the multiple reflection effect is not used at a measurement wavelength of 5 μm, whereas the measurement error is about 160 ° C. when the multiple reflection effect is used. The measurement error is about 30 ° C. However, even when the multiple reflection effect is used, an error of about 85 ° C. at a measurement wavelength of 5 μm and about 20 ° C. at 0.9 μm is generated on a substrate with an emissivity ε = 0.3.
[0061]
<< 2-2.2 Temperature Measurement with Two Radiation Thermometers >>
By using the multiple reflection effect as described above, the measurement error due to the difference in the emissivity of the substrate can be reduced, but it is not sufficient for measuring the temperature of the substrate. Therefore, in the first embodiment, a temperature measurement method using two radiation thermometers is used.
[0062]
FIG. 11 is a graph showing temperature measurement results by two radiation thermometers that take in light having different degrees of multiple reflection effect. In FIG. 11, temperature measurement is performed with the substrate emissivity fixed (for example, ε = 1.0). In this case, as shown in FIG. 11, a radiation thermometer having a large multiple reflection effect exhibits a higher temperature than a radiation thermometer having a smaller effect. That is, there is a difference D in temperature indicated by both radiation thermometers.
[0063]
In the first embodiment, by using two radiation thermometers 4a and 4b that take in light having different degrees of multiple reflection effect, the multiple reflection effect is large due to the difference in radiant energy intensity value corresponding to the difference in indicated temperature. The substrate temperature can be measured more accurately (measurement error is smaller than measurement error ER) than when the radiation thermometer is measured alone (measurement error ER).
[0064]
<< 2-3.2 Temperature measurement by radiation thermometer >>
In the above-described temperature measurement using multiple reflection, the degree of multiple reflection varies depending on the shape of the reflection surface 21E and the like. Therefore, when the effective reflectance R that is a parameter indicating the degree of multiple reflection is used instead of the reflectance r of the reflecting surface 21E in the expression 1, the expression 1 is expressed as the following expression.
[0065]
[Expression 2]

[0066]
Here, εa represents the apparent emissivity.
[0067]
Next, consider the case of performing temperature measurement using two radiation thermometers. In this case, large and small multiple reflection effects are intentionally provided for both radiation thermometers. In the first embodiment, as will be described later, the two radiation thermometers are provided with optical systems having different viewing angles. The effective reflectance having a large multiple reflection effect is Rmain, and the small effective reflectance is Rsub.
[0068]
When the emissivity of the substrate is εW, the radiant energy intensities Imain and Isub incident on each radiation thermometer are expressed by the following equation (2):
[0069]
[Equation 3]

[0070]
[Expression 4]

[0071]
It becomes. Here, Ib represents the radiant energy intensity (hereinafter referred to as “blackbody radiant energy intensity Ib”) when the substrate is regarded as a black body.
[0072]
If εW is eliminated from the formulas 3 and 4,
[0073]
[Equation 5]

[0074]
It becomes. Here, S is a constant that can be expressed by Rmain and Rsub, and indicates the relative effective reflectivity based on the relative change of the two effective reflectivities.
[0075]
And the temperature measurement of a board | substrate is performed as follows.
[0076]
First, the radiant energy intensities Imain and Isub are calculated from a signal output from the detector 422 of each radiation thermometer. Then, the radiant energy intensity Ib is obtained by using these radiant energy intensities Imain and Isub and the relative effective reflectance S obtained in advance in the equation (5).
[0077]
By the way, the Planck radiation formula, which is a relational expression between the temperature of the black body and the radiant energy intensity I of the black body, is expressed by the following equation when the Planck constant is C1, C2, the wavelength of interest is λ, and the temperature is T. Is done.
[0078]
[Formula 6]

[0079]
When this formula is transformed into a formula for the temperature T of the black body,
[0080]
[Expression 7]

[0081]
It becomes.
[0082]
Here, since Equation 7 is an equation when the object to be measured is a black body, if this is used as it is for temperature measurement of the substrate (with an emissivity ε other than “1”), the measurement error increases. Then, when rewriting the formula 7 using the substrate temperature TW and the black body radiant energy intensity Ib,
[0083]
[Equation 8]

[0084]
It becomes. Here, the correction coefficient A is a coefficient obtained by correcting the Planck constant C2 so that the substrate temperature TW obtained from the black body radiant energy intensity Ib becomes the set temperature Ttc (that is, TW = Ttc). It depends on the sensitivity and the degree of loss of light energy up to the detector. Then, the temperature TW of the substrate is obtained by the equation (8).
[0085]
<< 2-4. Substrate heat treatment procedure >>
FIG. 12 is a flowchart showing a substrate processing procedure in the first embodiment. Based on the above temperature measurement principle, the procedure of the heat treatment while obtaining the temperature of an actual substrate is as follows.
[0086]
A substrate is carried into the substrate processing apparatus 1 by an external transfer device (not shown) (step S1), set on the support ring 711, and then heating of the substrate is started (step S2). The substrate is rotated as the substrate is heated, and the gas is supplied as necessary.
[0087]
Next, the conversion part 5 calculates | requires radiant energy intensity | strength Imain and Isub with the output signal of radiation thermometer 4a, 4b, continuing a heating of a board | substrate (step S3).
[0088]
Further, the conversion unit 5 uses the obtained radiant energy intensities Imain and Isub and the relative effective reflectance S obtained in advance as will be described later in the equation (5) to obtain black when the substrate is regarded as a black body. The body radiation energy intensity Ib is calculated (step S4).
[0089]
Further, the converter 5 obtains the substrate temperature TW by substituting the correction coefficient A obtained in advance as described later and the obtained black body radiant energy intensity Ib into the equation (8) (step S5).
[0090]
The control unit 6 compares the obtained substrate temperature TW with a preset temperature Ttc set in advance, and performs feedback control of the power supplied to the lamp 31 (step S6).
[0091]
Then, the control unit 6 determines the end of the processing time (step S7), and continues the processing from step S3 to step S7 until the set processing time elapses. Then, when the processing time has elapsed, the external transfer device carries the substrate out (step S8).
[0092]
Next, the control unit 6 determines the end of the heating process for all the substrates prepared by a signal from an external substrate supply / discharge mechanism (not shown) (step S9), and if the heating process for all the substrates has not been completed. Returning to step S <b> 1, the external transfer device carries in the next substrate. If the processing is finished, the substrate processing with a series of heating is finished.
[0093]
Thus, the heat treatment for one substrate is completed. However, when a plurality of substrates are subjected to heat treatment, the above-described substrate heat treatment is further repeated for each substrate.
[0094]
By the way, as described above, it is necessary to obtain the relative effective reflectance S and the correction coefficient A in advance for the temperature measurement of the substrate. Therefore, in the first embodiment, the radiation thermometer is calibrated by determining the relative effective reflectance S and determining the correction coefficient A prior to actual temperature measurement. Hereinafter, these determination methods will be described.
[0095]
<< 2-5. Determination of relative effective reflectivity and correction factor >>
The relative effective reflectance S and the correction coefficient A in the first embodiment are determined as follows. In other words, a plurality of types of substrates having different emissivities of the same type as substrates to be subjected to actual substrate processing by the above processing procedure later are prepared, and each of them is prepared as a substrate processing apparatus. Heat by 1. Then, at the stage where the temperature of the reference substrate measured by the thermocouple reaches the set temperature Ttc, the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... Is measured for each reference substrate. Then, the black body radiant energy intensity Ib and the relative effective reflectance S are obtained based on these measured values.
[0096]
FIG. 13 is a graph showing how the black body radiant energy intensity Ib is obtained based on the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2). In FIG. 13, the measured values of the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... Are represented as points in a two-dimensional plane with Imain on the vertical axis and Isub on the horizontal axis. In the figure, the set of points represented by the same symbol (circle, square, etc.) is the radiant energy intensity with respect to a plurality of types of substrates and the same type of reference substrate that are processed continuously under the same radiation thermometer 4 settings. The measurement results of (Imain1, Isub1), (Imain2, Isub2). Note that only one set of data (triangles) is given a reference symbol.
[0097]
In the first embodiment, when the radiant energy intensities (Imain1, Isub1), (Imain2, Isub2)... Are represented on a plane, for example, the least square method is used so as to reduce the error from each point. An approximate curve AL passing through the vicinity of each point is obtained.
[0098]
By the way, if ε = 1 in the equation (2), the apparent emissivity εa does not depend on the effective reflectance R. Therefore, when the radiant energy intensity (Imain, Isub) is originally measured for a black body, Imain = Must be Isub. Therefore, the black body radiant energy intensity Ib should be located on the straight line SL of Imain = Isub in the graph of FIG. Therefore, when obtaining the black body radiant energy intensity Ib, the Imain (or Isub) component value at the intersection of the approximate curve AL and the straight line SL of Imain = Isub is defined as the black body radiant energy intensity Ib. Then, the relative effective reflectance S is obtained by using the black body radiant energy intensity Ib obtained in this way and the arbitrary points (Imain, Isub) on the obtained approximate curve in the equation (5).
[0099]
The method for obtaining the correction coefficient A is as follows. That is, the obtained black body radiant energy intensity Ib and set temperature Ttc are substituted into the equation (8) together with the measurement wavelength λ of the radiation thermometer. However, the set temperature Ttc is substituted for the substrate temperature TW. As a result, the correction coefficient A is obtained.
[0100]
As described above, in the first embodiment, the correction coefficient A is obtained, and in the actual substrate processing, the substrate temperature TW is obtained using the equation (8). Compared with the case of obtaining the substrate temperature using the black body radiant energy intensity Ib, the substrate temperature can be obtained more accurately.
[0101]
Further, the emissivities of the substrate and the reference substrate are not obtained in the above-described processing for measuring the temperature of the substrate and determining the relative effective reflectance S and the correction coefficient A using the reference substrate. Thus, in the first embodiment, it is not necessary to obtain the emissivities of the substrate and the reference substrate.
[0102]
Hereinafter, the procedure for determining the relative effective reflectance S and the correction coefficient A by the above method will be described with reference to FIG.
[0103]
First, the operator sets one reference substrate on the support ring 711 (step S11), and starts heating the reference substrate (step S12).
[0104]
At the same time, the controller 6 determines whether or not the set temperature Ttc has been reached based on the temperature signal from the thermocouple embedded in the reference substrate (step S13). If the temperature does not reach the set temperature Ttc, heating is continued while measuring the temperature with a thermocouple, and the determination in step S13 is repeated until the temperature of the reference substrate reaches the set temperature Ttc.
[0105]
When the temperature of the reference substrate reaches the set temperature Ttc, the conversion unit 5 obtains the radiant energy intensity (Imain1, Isub1) based on the output signals of the radiation thermometers 4a and 4b under the control of the control unit 6 (step S14). To the control unit 6.
[0106]
Next, the operator determines whether or not measurement has been completed for all the reference substrates (step S15). If not completed, the operator replaces the reference substrate and sets another reference substrate on the support ring 711. On the other hand, the processes of steps S11 to S13 are performed, and when the set temperature Ttc is reached, the radiant energy intensity (Imain2, Isub2), (Imain3, Isub3),... On the other hand, if it is finished, the process proceeds to step S16.
[0107]
Next, the operator obtains an approximate curve AL on the Imain-Isub plane based on the obtained radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... The black body radiant energy intensity Ib and the relative effective reflectance S are calculated and input to the conversion unit 5 through input means (not shown), and the conversion unit 5 stores them (step S16).
[0108]
Finally, the operator substitutes the obtained black body radiant energy intensity Ib and the set temperature Ttc into the formula 8 together with the measurement wavelength λ of the radiation thermometer 4 (however, the set temperature Ttc is substituted into TW). Thus, the correction coefficient A is calculated and input to the conversion unit 5 through the input means, and the conversion unit 5 stores it (step S17).
[0109]
Thus, the relative effective reflectance S and the correction coefficient A were obtained. Based on these, the substrate processing is performed while controlling the temperature of the substrate as described above.
[0110]
As described above, according to the first embodiment, the radiant energy intensity Imain, Isub of light from the inside of the container body 21 is measured, and black body radiation when the substrate is regarded as a black body based on the measured intensity. In order to calculate the energy intensity Ib and calculate the temperature of the substrate based on the black body radiant energy intensity Ib, the temperature is measured without contaminating the substrate as in the case of the contact-type temperature measuring means, and more Accurate temperature control can be performed.
[0111]
Further, according to the first embodiment, the plurality of radiation thermometers 4a and 4b have the optical systems 421 having different viewing angles of the light incident on each of them, and measure the radiant energy intensity Imain and Isub by them, Since the temperature of the substrate is obtained based on them, two types of radiant energy intensity can be measured without providing a large opening, so that the uniformity of the temperature distribution of the substrate is not impaired, that is, the processing quality of the substrate is deteriorated. Therefore, the temperature of the substrate can be measured and accurate temperature management can be performed.
[0112]
Further, according to the first embodiment, the relative effective reflectance S is obtained based on the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2). In order to calculate the substrate temperature, the relative effective reflectance S can be obtained from only one reference substrate, and the substrate temperature can be calculated more accurately than when calculating the substrate temperature. It is possible to perform temperature control of a simple substrate.
[0113]
Further, when substrate processing is performed on a plurality of different types of substrates, since the plurality of reference substrates are the same type as the plurality of types of substrates, the relative effective reflectivity S used in actual substrate processing is used. Can be reduced in error for temperature measurement of the plurality of types of substrates, and the accuracy of temperature measurement can be improved.
[0114]
Further, there is little error with respect to each point when the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... Obtained for each of the plurality of reference substrates is expressed as a point in the Imain-Isub plane. Since the approximate curve is obtained and the relative effective reflectance S is obtained based on the approximate curve, the relative effective reflectance S with less error can be obtained, and the accuracy of temperature measurement can be further improved.
[0115]
Furthermore, according to the first embodiment, since the correction coefficient A is obtained and the temperature of the substrate is calculated using the obtained correction coefficient A, it is possible to obtain the reference substrate and the accurate emissivity of the substrate without obtaining the substrate. The temperature can be determined accurately.
[0116]
<3. Temperature Measurement Principle of Second Embodiment>
In the substrate processing of the first embodiment, the substrate temperature TW is accurately obtained using the equation (8). However, the radiation thermometer has already been calibrated or the temperature measurement accuracy is required to be high. When the calibration of the radiation thermometer is unnecessary, the radiation obtained by the relative effective reflectance S obtained in advance in the equation (5) in the radiant energy intensity I of the equation (7) instead of the equation (8). By substituting the energy intensity Ib, the temperature T of the obtained black body can be regarded as the substrate temperature TW.
[0117]
In this case, the substrate processing procedure is the same as that shown in FIG. In this case, however, the radiation thermometer is not calibrated. In other words, since the equation (8) is not used in the temperature measurement in the second embodiment, it is not necessary to obtain the correction coefficient A in the equation. For this reason, in the second embodiment, only one reference substrate in which a thermocouple is embedded is used, and only the process of determining the relative effective reflectance S is performed.
[0118]
FIG. 15 is a flowchart showing a determination processing procedure for the relative effective reflectance S in the second embodiment. Hereinafter, this processing procedure and its principle will be described with reference to FIG.
[0119]
Even in this process, the processes in steps S21 to S24 are the same as the processes in steps S11 to S14 in FIG.
[0120]
Next, the operator calculates the black body radiant energy intensity Ib and the relative effective reflectance S based on the set temperature Ttc and the obtained radiant energy intensity (Imain, Isub), and supplies it to the converter 5 through the input means. The conversion unit 5 stores the input (step S25). Specifically, first, the set temperature Ttc is regarded as the temperature T of the black body, and the black body radiant energy intensity Ib is obtained using the equation (6). Next, the relative effective reflectance S is obtained by using the measured radiant energy intensity (Imain, Isub) and the obtained black body radiant energy intensity Ib in the equation (5).
[0121]
Thus, the relative effective reflectance S was obtained. Based on this, the substrate processing is performed while controlling the temperature of the substrate as described above.
[0122]
As described above, according to the second embodiment, the same effects as the effects other than the effects obtained by using the plurality of reference substrates and the correction coefficient A in the first embodiment. have.
[0123]
<4. Modification>
In the first and second embodiments, examples of the substrate processing apparatus and the substrate processing method using the substrate processing apparatus have been described. However, the present invention is not limited to this.
[0124]
For example, in the above embodiment, only one set of radiation thermometers 4a and 4b is provided. However, a plurality of sets of radiation thermometers 4a and 4b are provided at different positions from the shaft 21C, and each part of the substrate is provided. It is good also as what performs temperature measurement and temperature management in. In addition, it is possible to change the two states of the radiation thermometers 4a and 4b by providing one that can move the lens in the optical axis direction so that the optical system of the radiation thermometer 4 can be scaled. Good.
[0125]
In the above embodiment, the substrate processing apparatus 1 irradiates the substrate 9 with the light from the lamp 31 through the quartz window 22, but the heating means is not limited to the lamp, and the heater Etc.
[0126]
The minute opening 21H may have any size as long as the temperature can be measured without impairing the uniformity of the substrate temperature. In addition, as a magnitude | size of the micro opening part 21H which satisfy | fills such conditions sufficiently, a diameter of 1-3 mm is preferable.
[0127]
Moreover, in the said embodiment, although temperature measurement is performed with the radiation thermometer 4 using the thermopile 422a, as long as temperature measurement can be performed using the light from the minute opening part 21H, another thermometer Even so, the present invention can be used.
[0128]
Further, in the above embodiment, it has been described that the minute opening 21H and the detector 422 are arranged in a substantially optically conjugate relationship, but this is because the detector 422 detects the light from the minute opening 21H. An arrangement relationship in which light is collected on the detector 422 to such an extent that temperature measurement can be performed.
[0129]
In addition, when the substrate 9 is processed in a processing environment in which the detection window member 411 is not contaminated, a configuration for supplying gas to the minute opening 21H may not be provided.
[0130]
In the above embodiment, the optical axis 4J of the optical system 421 is described as being perpendicular to the surface of the substrate 9, but the present invention is not limited to this.
[0131]
In the above embodiment, the optical system 421 uses a lens, but a reflecting mirror may be used.
[0132]
In the above embodiment, when the relative effective reflectance S or the like is obtained, the radiant energy intensity is measured when the reference substrate reaches the set temperature Ttc, and the relative effective reflectance S or the like is obtained based on the measured radiant energy intensity. If some deterioration in accuracy does not become a problem, the radiant energy intensity in a state where the reference substrate is at another temperature may be obtained. In this case, the relative effective reflectance S or the like may be obtained using the temperature value measured by the thermocouple.
[0133]
In the first embodiment, when the relative effective reflectance S is obtained, an approximate curve is obtained for the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... And based on the approximate curve. The black body radiant energy intensity Ib and the relative effective reflectance S were obtained. In the equation (5), the measured radiant energy intensity (Imain1, Isub1) using the black body radiant energy intensity Ib and the relative effective reflectance S as parameters. , (Imain2, Isub2), etc., and the black body radiation energy intensity Ib and the relative effective reflectance S may be obtained by an approximation method such as a least square method. When the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2) is measured with two reference boards, the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2) is measured according to the equation (5). The black body radiant energy intensity Ib and the relative effective reflectance S may be obtained by solving simultaneous equations obtained by substituting values. This is equivalent to performing the least squares method using the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2) in the equation (5).
[0134]
In the first embodiment, the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... Is measured for the same type of reference substrate as the type of substrate to be processed, and an approximate curve is obtained for them. Although it was determined, the approximate curve may be determined by measuring the radiant energy intensity of a plurality of reference substrates of a type different from the substrate that is actually subjected to substrate processing. Further, the radiant energy intensity (Imain1, Isub1), (Imain2, Isub2)... Measured in advance for a typical substrate is stored and stored in a database, and is read out and used before substrate processing. The black body radiant energy intensity Ib and the relative effective reflectance S may be calculated.
[0135]
【The invention's effect】
As described above, according to the first to sixth aspects of the present invention, the radiant energy intensity is measured through the opening in the reflection surface from the substrate side, and the substrate is determined to be a black body based on the radiant energy intensity. In order to calculate the black body radiant energy intensity when it is considered, and to calculate the temperature of the substrate based on the black body radiant energy intensity, the temperature is measured without contaminating the substrate as in the case of contact-type temperature measurement means. By measuring, more accurate temperature management can be performed.
[0136]
Also , Double A number of intensity measurement means have optical systems with different viewing angles of radiant energy incident on each of them, and radiant energy intensity is measured by them, and a large opening is provided to determine the substrate temperature based on them. 2 types of radiant energy intensity can be measured, and the temperature of the substrate can be measured and accurately controlled without impairing the uniformity of the temperature distribution of the substrate, that is, without deteriorating the processing quality of the substrate. it can.
[0137]
Claims 3 According to the invention, since the relative effective reflectance is obtained based on the radiant energy intensity of each of the plurality of reference substrates, and the temperature of the substrate is calculated using the relative effective reflectance, the relative effective reflectance is obtained by using only one reference substrate. As compared with the case where the temperature of the substrate is calculated by calculating the temperature of the substrate, the temperature of the substrate can be calculated more accurately and the temperature management of the substrate can be performed more accurately.
[0138]
Claims 4 According to the invention, the strength measurement step, the strength calculation step, and the temperature calculation step are performed on a plurality of different types of substrates, and the plurality of reference substrates are the same type as the plurality of types of substrates. The relative effective reflectance used in actual substrate processing can be reduced in error for temperature measurement of the plurality of types of substrates, and the accuracy of temperature measurement can be improved.
[0139]
Claims 5 According to the invention, for each point when the set of the first radiant energy intensity Imain and the second radiant energy intensity Isub obtained for each of the plurality of reference substrates is expressed as a point in the Imain-Isub plane. Thus, an approximate curve with less error is obtained, and the relative effective reflectance is obtained based on the approximate curve. Therefore, the relative effective reflectance with less error can be obtained, and the accuracy of temperature measurement can be further improved.
[0140]
And claims 6 According to the invention, since the correction coefficient obtained by correcting the Planck constant is obtained and the substrate temperature is calculated using the obtained correction coefficient, the substrate temperature is accurately calculated without obtaining the accurate emissivity of the reference substrate or the substrate. Can be requested.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a substrate processing apparatus according to an embodiment of the present invention.
FIG. 2 is a bottom view of the substrate processing apparatus shown in FIG.
FIG. 3 is a longitudinal sectional view of one radiation thermometer attached to the container main body.
FIG. 4 is a longitudinal sectional view of another radiation thermometer attached to the container main body.
FIG. 5 is a top view showing a flange portion and a gas supply pipe.
FIG. 6 is a partially enlarged view in the vicinity of a minute opening.
FIG. 7 is a diagram for explaining multiple reflection between a lower surface of a substrate and a reflecting surface.
FIG. 8 is a diagram showing the relationship between the emissivity of a substrate and the apparent emissivity due to the multiple reflection effect.
FIG. 9 is a diagram showing a relationship between a substrate emissivity and a temperature measurement error in temperature measurement without using the multiple reflection effect.
FIG. 10 is a diagram showing a relationship between a substrate emissivity and a temperature measurement error in temperature measurement using a multiple reflection effect.
FIG. 11 is a graph showing temperature measurement results with light having different degrees of multiple reflection effect.
FIG. 12 is a flowchart showing a substrate processing procedure in the first embodiment.
FIG. 13 is a graph showing how the black body radiant energy intensity is obtained in the first embodiment.
FIG. 14 is a flowchart showing a determination process procedure of a relative effective reflectance and a correction coefficient.
FIG. 15 is a flowchart showing a determination process procedure of a relative effective reflectance in the second embodiment.
[Explanation of symbols]
1 Substrate processing equipment
2 chambers
4L light
4a, 4b Radiation thermometer (strength measuring means in combination with 5)
5 Conversion unit (strength calculation means, temperature calculation means)
6 Control unit
9 Board
21E Reflective surface
21H Micro opening
31 Lamp (heating means)
421 optical system
422 detector
A Correction factor
Ib Black body radiation energy intensity
Imain, Isub Radiant energy intensity
S Relative effective reflectivity
VA1, VA2 Viewing angle

Claims (6)

A substrate processing apparatus for performing processing involving heating on a substrate,
Heating means for heating one surface of the substrate;
A reflective surface having an opening formed and facing the other surface of the substrate;
A plurality of intensity measuring means for measuring the radiant energy intensity by detecting the radiant energy from the substrate side with the detector through the opening;
Intensity calculating means for calculating black body radiant energy intensity when the substrate is regarded as a black body based on the radiant energy intensity measured by the intensity measuring means;
Temperature calculating means for calculating the temperature of the substrate based on the black body radiant energy intensity calculated by the intensity calculating means;
Equipped with a,
The plurality of intensity measuring means have optical systems having different viewing angles of radiant energy incident on each of the intensity measuring means,
The substrate processing apparatus , wherein the intensity calculating means calculates the black body radiant energy intensity based on a plurality of the radiant energy intensities measured by the plurality of intensity measuring means . Heating means for heating one surface of the substrate, a reflection surface which is formed with an opening and faces the other surface of the substrate, and radiant energy from the substrate side is detected by the detector through the opening. A substrate processing method using a substrate processing apparatus comprising an intensity measuring means for measuring the radiant energy intensity by detecting,
An intensity measuring step of measuring the radiant energy intensity by the intensity measuring means;
An intensity calculating step of calculating a black body radiant energy intensity when the substrate is regarded as a black body based on the radiant energy intensity measured in the intensity measuring step;
A temperature calculating step of calculating a temperature of the substrate based on the black body radiant energy intensity calculated in the intensity calculating step;
With
In the intensity measurement step, the plurality of radiant energy intensities incident through optical systems having different viewing angles are measured,
In the intensity calculation step, the black body radiant energy intensity is calculated based on a plurality of the radiant energy intensities measured in the intensity measurement step. The substrate processing method according to claim 2,
Before each of the above steps,
A reference intensity measuring step of measuring the radiant energy intensity of each of the plurality of reference substrates by the intensity measuring means while heating the plurality of reference substrates having different emissivities from each other by the substrate processing apparatus;
A reflectance calculating step of calculating a relative effective reflectance based on the radiant energy intensity of the plurality of reference substrates obtained in the reference intensity measuring step;
With
In the temperature calculating step, the temperature of the substrate is calculated using the value of the relative effective reflectance calculated in the reflectance calculating step. The substrate processing method according to claim 3,
The strength measurement step, the strength calculation step and the temperature calculation step are performed on a plurality of different types of substrates,
The substrate processing method, wherein the plurality of reference substrates are the same type as the plurality of types of substrates. The substrate processing method according to claim 3 or 4, wherein:
The reference intensity measuring step has a first radiant energy intensity I by the radiant intensity measuring means having two different viewing angles. main And second radiant energy intensity I sub Is to measure,
The reflectance calculation step includes
The first radiant energy intensity I obtained for each of the plurality of reference substrates. main And second radiant energy intensity I sub Set of I main -I sub A curve calculation step for obtaining an approximate curve with less error for each point when expressed as a point in the plane;
I main -I sub The approximate curve and straight line I in the plane main = I sub A reference black body intensity calculating step for calculating a component value of any of the intersections with the reference black body radiant energy intensity for the plurality of reference substrates;
I of any point on the approximate curve obtained in the curve calculation step main And I sub Calculating the relative effective reflectance from a component value and the reference black body radiant energy intensity obtained in the reference black body intensity calculating step;
A substrate processing method comprising: The substrate processing method according to claim 3, further comprising:
A reference black body intensity calculating step of calculating the black body radiant energy intensity based on the radiant energy intensity of each of the plurality of reference substrates obtained in the reference intensity measuring step;
A coefficient calculating step for obtaining a correction coefficient by correcting the Planck constant in the Planck radiation formula based on the black body radiant energy intensity obtained in the reference black body intensity calculating step;
The substrate processing method, wherein the temperature calculating step calculates the temperature of the substrate using the correction coefficient obtained in the coefficient calculating step.

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