JP3278782B2

JP3278782B2 - Semiconductor device manufacturing method and projection exposure apparatus

Info

Publication number: JP3278782B2
Application number: JP22522691A
Authority: JP
Inventors: 美代子野口
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 1991-08-09
Filing date: 1991-08-09
Publication date: 2002-04-30
Anticipated expiration: 2017-04-30
Also published as: JPH0547629A

Description

DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【産業上の利用分野】本発明は半導体デバイスの製造方
法及びそれを用いた投影露光装置に関し、具体的には半
導体素子の製造装置である所謂ステッパーにおいてレチ
クル面上のパターンの照明方法を変化させたときの投影
光学系の使用態様の変化における光学特性の変位のうち
少なくとも１つを調整し、高い光学性能が容易に得られ
るようにしたものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device and a projection exposure apparatus using the same. More specifically, the method for illuminating a pattern on a reticle surface is changed in a so-called stepper which is a semiconductor device manufacturing apparatus. In this case, at least one of the displacements of the optical characteristics due to the change of the use mode of the projection optical system is adjusted so that high optical performance can be easily obtained.

【０００２】[0002]

【従来の技術】最近の半導体素子の製造技術の進展は目
覚ましく、又それに伴う微細加工技術の進展も著しい。
特に光加工技術は１ＭＤＲＡＭの半導体素子の製造を境
にサブミクロンの解像力を有する微細加工を技術まで達
している。解像力を向上させる手段としてこれまで多く
の場合、露光波長を固定して、光学系のＮＡ（開口数）
を大きくしていく方法を用いていた。しかし最近では露
光波長をｇ線からｉ線に変えて、超高圧水銀灯を用いた
露光法により解像力を向上させる試みも種々と行なわれ
ている。2. Description of the Related Art Recent advances in semiconductor device manufacturing technology have been remarkable, and the accompanying fine processing technology has also advanced remarkably.
In particular, the optical processing technology has reached the fine processing technology having a submicron resolution since the manufacture of 1MDRAM semiconductor devices. In many cases, the exposure wavelength is fixed as a means for improving the resolution, and the NA (numerical aperture) of the optical system is increased.
Was used. However, recently, various attempts have been made to change the exposure wavelength from the g-line to the i-line and to improve the resolving power by an exposure method using an ultra-high pressure mercury lamp.

【０００３】露光波長としてｇ線やｉ線を用いる方法の
発展と共にレジストプロセスも同様に発展してきた。こ
の光学系とプロセスの両者が相まって、光リソグラフィ
が急激に進歩してきた。[0003] With the development of the method using g-line or i-line as the exposure wavelength, the resist process has also been developed. Together, the optics and the process have led to rapid advances in optical lithography.

【０００４】一般にステッパーの焦点深度はＮＡの２乗
に反比例することが知られている。この為サブミクロン
の解像力を得ようとすると、それと共に焦点深度が浅く
なってくるという問題点が生じてくる。It is generally known that the depth of focus of a stepper is inversely proportional to the square of NA. Therefore, when trying to obtain a submicron resolution, there arises a problem that the depth of focus becomes shallower.

【０００５】これに対してエキシマレーザーに代表され
る更に短い波長の光を用いることにより解像力の向上を
図る方法が種々と提案されている。短波長の光を用いる
効果は一般に波長に反比例する効果を持っていることが
知られており、波長を短くした分だけ焦点深度は深くな
る。On the other hand, various methods have been proposed for improving the resolving power by using light having a shorter wavelength typified by an excimer laser. It is known that the effect of using light of a short wavelength generally has an effect inversely proportional to the wavelength, and the depth of focus becomes deeper as the wavelength is shortened.

【０００６】短波長化の光を用いる他に解像力を向上さ
せる方法として位相シフトマスクを用いる方法（位相シ
フト法）が種々と提案されている。この方法は従来のマ
スクの一部分に、他の部分とは通過光に対して１８０度
の位相差を与える薄膜を形成し、解像力を向上させよう
とするものであり、ＩＢＭ社（米国）のＬｅｖｅｎｓｏ
ｎらにより提案されている。解像力ＲＰは波長をλ、パ
ラメータをｋ₁ 、開口数をＮＡとすると一般に式ＲＰ＝ｋ₁ λ／ＮＡで示される。通常０．７〜０．８が実用域とされるパラ
メータｋ₁ は、位相シフト法によれば０．３５ぐらい迄
大幅に改善できることが知られている。Various methods using a phase shift mask (phase shift method) have been proposed as a method of improving the resolving power in addition to using light having a shorter wavelength. According to this method, a thin film which gives a phase difference of 180 degrees with respect to passing light is formed on a part of a conventional mask to improve the resolving power, and the Levenso of IBM (USA) is used.
n et al. The resolving power RP is generally represented by the formula RP = k ₁ λ / NA, where λ is the wavelength, k _{1 is} the parameter, and NA is the numerical aperture. Usually 0.7-0.8 parameter k ₁ is a practical range is known to be significantly improved to about 0.35, according to the phase shift method.

【０００７】位相シフト法には種々のものが知られてお
り、それらは例えば日経マイクロデバイス１９９０年７
月号１０８ページ以降の福田等の論文に詳しく記載され
ている。[0007] Various types of phase shift methods are known, for example, Nikkei Micro Devices, July 1990.
It is described in detail in the article by Fukuda et al.

【０００８】しかしながら実際に空間周波数変調型の位
相シフトマスクを用いて解像力を向上させるためには未
だ多くの問題点が残っている。例えば現状で問題点とな
っているものとして以下のものがある。（イ）．位相シフト膜を形成する技術が未確立。（ロ）．位相シフト膜用の最適なＣＡＤの開発が未確
立。（ハ）．位相シフト膜を付けれないパターンの存在。（ニ）．（ハ）に関連してネガ型レジストを使用せざる
をえないこと。（ホ）．検査、修正技術が未確立。However, there are still many problems in improving the resolving power by using a spatial frequency modulation type phase shift mask. For example, the following are the problems at present. (I). The technology to form a phase shift film has not been established. (B). Development of the optimal CAD for the phase shift film has not been established. (C). Existence of a pattern without a phase shift film. (D). In connection with (c), a negative resist must be used. (E). Inspection and repair technology not established.

【０００９】このため実際に位相シフトマスクを利用し
て半導体素子を製造するには様々な障害があり、現在の
ところ大変困難である。Therefore, there are various obstacles in actually manufacturing a semiconductor device using a phase shift mask, and it is very difficult at present.

【００１０】これに対して本出願人はパターン形状や解
像線幅の大小に応じて照明方法を適切に構成することに
より、より解像力を高めた露光方法を及びそれを用いた
投影露光装置を特願平３−２８６３１号（平成３年２月
２２日出願）で提案している。On the other hand, the present applicant has proposed an exposure method with a higher resolution and a projection exposure apparatus using the same by appropriately configuring the illumination method according to the pattern shape and the size of the resolution line width. This is proposed in Japanese Patent Application No. 3-28631 (filed on February 22, 1991).

【００１１】[0011]

【発明が解決しようとする課題】然しながら、前記の解
像限界を拡大する方法において、パターン寸法がより微
細化するため、照明系を含めた光学系の諸性能（歪曲誤
差、倍率誤差、像面湾曲等）に対してより厳しく制限す
る必要がある。例えば、このうち歪曲収差、倍率誤差は
電子回路パターンが形成されている第１物体面であるレ
チクルと第２物体面であるウエハとを重ね合わせる際に
重要なマッチング精度に影響を与えるものである。However, in the above-described method for increasing the resolution limit, the performance of the optical system including the illumination system (distortion error, magnification error, image plane It is necessary to restrict more strictly for curvature and the like. For example, among these, distortion and magnification error affect important matching accuracy when a reticle as a first object surface on which an electronic circuit pattern is formed and a wafer as a second object surface are superimposed. .

【００１２】更に、この光学系の諸性能に影響を与える
光学系の収差は、周囲の環境、特に気圧や温度によって
変化することや、露光によって投影光学系が露光エネル
ギーを吸収し、光学要素（例えば屈折率、形状）が変化
するため、このような変化も無視できなくなっている。Further, aberrations of the optical system that affect various performances of the optical system vary depending on the surrounding environment, particularly, atmospheric pressure and temperature, and the projection optical system absorbs exposure energy by exposure, and the optical element ( For example, since the refractive index and the shape change, such a change cannot be ignored.

【００１３】一般に投影光学系の収差は瞳面上の波面収
差となって表われる。一方、照明光は投影光学系の瞳に
様々な角度で入射するが、この傾いた入射光は波面収差
の位相ずれを引き起こす。照明法が切り替わるとこの角
度分布が種々と変化し、結像における収差の影響の仕方
が異なってくる。Generally, the aberration of the projection optical system appears as a wavefront aberration on the pupil plane. On the other hand, the illumination light is incident on the pupil of the projection optical system at various angles, and the inclined incident light causes a phase shift of the wavefront aberration. When the illumination method is switched, this angular distribution changes variously, and the way of influence of aberration on image formation differs.

【００１４】照明法を変えると投影光学系を通過する光
束の光路が異なってくる。例えば本出願人が先の特願平
３−２８６３１号の投影露光装置において提案したよう
にレチクル面のパターンの方向や解像線幅の大小によっ
て照明法を種々と変えて解像力を向上させると、それに
伴ない投影光学系内を通過する光束の光路が変化してく
る。そうすると投影光学系の有する諸収差、例えば歪曲
収差、像面湾曲や倍率誤差がその都度異なってくる。
又、時間的な収差変化量も異なってくる。If the illumination method is changed, the optical path of the light beam passing through the projection optical system will be different. For example, as proposed by the present applicant in the projection exposure apparatus of Japanese Patent Application No. 3-28631, if the illumination method is changed in various ways depending on the direction of the pattern on the reticle surface and the size of the resolution line width to improve the resolution, Accordingly, the optical path of the light beam passing through the projection optical system changes. Then, various aberrations of the projection optical system, such as distortion, field curvature and magnification error, are different each time.
In addition, the amount of change in aberration over time also differs.

【００１５】本発明はこのように照明方法を種々と変え
て解像力を向上させようとしたときの投影光学系の光路
の変更に伴なう、即ち投影光学系の収差の寄与の仕方の
違いから生じる光学特性の違いを調整し、常に高い解像
力を維持することができる半導体デバイスの製造方法及
びそれを用いた投影露光装置の提供を目的とする。According to the present invention, the light path of the projection optical system is changed when the resolution is improved by changing the illumination method in various ways. It is an object of the present invention to provide a method of manufacturing a semiconductor device capable of adjusting a difference in generated optical characteristics and maintaining a high resolution at all times, and a projection exposure apparatus using the same.

【００１６】[0016]

【課題を解決するための手段】本発明の半導体デバイス
の製造方法は、（アー１）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影するこ
とによって前記回路パターンで前記基板を露光する段階
を含む半導体デバイスの製造方法において、前記露光に
よる前記投影光学系の光学特性の変化を補正する調整と
は独立に、前記２次光源の形状の変更に応じて前記投影
光学系の投影倍率、対称歪曲収差、像面湾曲、片ボケ、
ピボタル傾きのうちの少なくとも１つを調整することを
特徴とする半導体デバイスの製造方法。（ア−２）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影する段
階を含む半導体デバイスの製造方法において、前記投影
光学系の投影倍率、対称歪曲収差、像面湾曲、片ボケ及
びピボタル傾きのうちの少なくとも１つの前記２次光源
の形状の変更よる変化を補正することを特徴とする半導
体デバイスの製造方法。（ア−３）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影する段
階を含む半導体デバイスの製造方法において、前記２次
光源の形状の変更により変化する前記投影光学系の投影
倍率、対称歪曲収差、像面湾曲、片ボケ及びピボタル傾
きのうちの少なくとも一つを調整することを特徴とする
半導体デバイスの製造方法。（ア−４）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影するこ
とによって前記回路パターンで前記基板を露光する段階
を含む半導体デバイスの製造方法において、前記露光に
よる前記投影光学系の光学特性の変化を補正する調整と
は独立に、前記２次光源の形状の変更に応じて前記投影
光学系の少なくとも１つの光学特性を調整するものであ
って、前記回路パターンの最小線幅が比較的大きな第１
原板と回路パターンの最小線幅が比較的小さな第２原板
とが使用される際、該第１原板を使用する場合には光源
部が光軸近傍にある２次光源が形成され、該第２原板を
使用する場合には、前記光軸を原点に直交座標を定めた
時、光源部が前記直交座標の４つの象限の夫々に独立し
て存する２次光源が使用されることを特徴とする半導体
デバイスの製造方法。（ア−５）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影する段
階を含む半導体デバイスの製造方法において、前記投影
光学系の少なくとも１つの光学特性の前記２次光源の形
状の変更よる変化を補正するものであって、前記回路パ
ターンの最小線幅が比較的大きな第１原板と回路パター
ンの最小線幅が比較的小さな第２原板とが使用される
際、該第１原板を使用する場合には光源部が光軸近傍に
ある２次光源が形成され、該第２原板を使用する場合に
は、前記光軸を原点に直交座標を定めた時、光源部が前
記直交座標の４つの象限の夫々に独立して存する２次光
源が使用されることを特徴とする半導体デバイスの製造
方法。（ア−６）光源からの光で２次光源を形成し、該２次光
源からの光束により回路パターンを照明し、該照明され
た回路パターンを投影光学系により基板上に投影する段
階を含む半導体デバイスの製造方法において、前記２次
光源の形状の変更により変化する前記投影光学系の少な
くとも一つの光学特性を調整するものであって、前記回
路パターンの最小線幅が比較的大きな第１原板と回路パ
ターンの最小線幅が比較的小さな第２原板とが使用され
る際、該第１原板を使用する場合には光源部が光軸近傍
にある２次光源が形成され、該第２原板を使用する場合
には、前記光軸を原点に直交座標を定めた時、光源部が
前記直交座標の４つの象限の夫々に独立して存する２次
光源が使用されることを特徴とする半導体デバイスの製
造方法。である。According to the present invention, there is provided a method of manufacturing a semiconductor device, comprising: (a) forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source; A method for manufacturing a semiconductor device, comprising exposing the substrate with the circuit pattern by projecting the illuminated circuit pattern onto the substrate by a projection optical system, wherein a change in optical characteristics of the projection optical system due to the exposure is corrected. Independent of the adjustment to be performed, the projection magnification of the projection optical system, symmetric distortion, field curvature, one-sided blur,
A method of manufacturing a semiconductor device, comprising adjusting at least one of a pivotal inclination. (A-2) forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system. In the method of manufacturing a semiconductor device, a change due to a change in a shape of the secondary light source, which is at least one of a projection magnification, a symmetric distortion, a field curvature, a one-sided blur, and a tilt of the projection optical system, is corrected. Manufacturing method of a semiconductor device. (A-3) forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system. In the method of manufacturing a semiconductor device, adjusting at least one of a projection magnification, a symmetric distortion, a field curvature, a one-sided blur, and a tilt of the projection optical system, which is changed by changing a shape of the secondary light source. A method for manufacturing a semiconductor device. (A-4) Forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system. In a method for manufacturing a semiconductor device including exposing the substrate with a circuit pattern, independently of adjustment for correcting a change in optical characteristics of the projection optical system due to the exposure, according to a change in the shape of the secondary light source. Adjusting at least one optical characteristic of the projection optical system, wherein the first line width of the circuit pattern is relatively large;
When an original plate and a second original plate having a relatively small minimum line width of a circuit pattern are used, when the first original plate is used, a secondary light source having a light source portion near the optical axis is formed, and the second light source is formed. When an original plate is used, when orthogonal coordinates are determined with the optical axis as the origin, a secondary light source is used in which the light source unit exists independently in each of the four quadrants of the orthogonal coordinates. A method for manufacturing a semiconductor device. (A-5) Forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system. In the method of manufacturing a semiconductor device, a change in a shape of the secondary light source of at least one optical characteristic of the projection optical system is corrected, and a first original plate having a relatively large minimum line width of the circuit pattern is provided. When a second original plate having a relatively small circuit pattern minimum line width is used, when the first original plate is used, a secondary light source having a light source portion near the optical axis is formed, and the second original plate is formed. In the case of using a semiconductor, when the orthogonal coordinates are determined with the optical axis as the origin, a secondary light source is used in which the light source unit independently exists in each of the four quadrants of the orthogonal coordinates. Device manufacturing method. (A-6) forming a secondary light source with light from a light source, illuminating a circuit pattern with a light beam from the secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system. In the method for manufacturing a semiconductor device, at least one optical characteristic of the projection optical system, which is changed by changing the shape of the secondary light source, is adjusted, and a first original plate having a relatively large minimum line width of the circuit pattern is provided. When a second original plate having a relatively small circuit pattern minimum line width is used, when the first original plate is used, a secondary light source having a light source portion near the optical axis is formed, and the second original plate is formed. In the case of using a semiconductor, when the orthogonal coordinates are determined with the optical axis as the origin, a secondary light source is used in which the light source unit independently exists in each of the four quadrants of the orthogonal coordinates. Device manufacturing method. It is.

【００１７】又、本発明の半導体デバイスの製造方法は
前記投影光学系の投影倍率や対称歪曲収差を調整するた
めに前記回路パターンと前記投影光学系の間隔が調整さ
れることを特徴としている。Further, the method of manufacturing a semiconductor device according to the present invention is characterized in that a distance between the circuit pattern and the projection optical system is adjusted in order to adjust a projection magnification and a symmetric distortion of the projection optical system.

【００１８】又、本発明の半導体デバイスの製造方法は
前記投影光学系の投影倍率や対称歪曲収差を調整せしめ
るべく前記投影光学系の屈折力が調整されることを特徴
としている。Further, the method of manufacturing a semiconductor device according to the present invention is characterized in that the refractive power of the projection optical system is adjusted so as to adjust the projection magnification and the symmetric distortion of the projection optical system.

【００１９】又、本発明の投影露光装置は、（イ−１）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、投影露光による
該投影光学系の光学特性の変化を補正する調整とは独立
に、前記２次光源の形状の変更に応じて前記投影光学系
の投影倍率、対称歪曲収差、像面湾曲、片ボケ及びピボ
タル傾きのうちの少なくとも一つを調整する手段を有す
ることを特徴とする投影露光装置。（イ−２）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、前記投影光学系
の投影倍率、対称歪曲収差、像面湾曲、片ボケ及びピボ
タル傾きのうちの少なくとも一つの前記２次光源の形状
の変更による変化を補正する手段を有することを特徴と
する投影露光装置。（イ−３）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、前記２次光源の
形状の変更により変化する前記投影光学系の投影倍率、
対称歪曲収差、像面湾曲、片ボケ及びピボタル傾きのう
ちの少なくとも一つを調整する手段を有することを特徴
とする投影露光装置。（イ−４）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、投影露光による
該投影光学系の光学特性の変化を補正する調整とは独立
に、前記２次光源の形状の変更に応じて前記投影光学系
の少なくとも１つの光学特性を調整する手段を有し、前
記パターンの最小線幅が比較的大きな第１原板と前記パ
ターンの最小線幅が比較的小さな第２原板とが使用され
る際、該第１原板を使用する場合には光源部が光軸近傍
にある２次光源が形成され、該第２原板を使用する場合
には、前記光軸を原点に直交座標を定めた時、光源部が
前記直交座標の４つの象限の夫々に独立して存する２次
光源が使用されることを特徴とする投影露光装置。（イ−５）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、前記２次光源の
形状の変更による前記投影光学系の少なくとも一つの光
学特性の変化を補正する手段を有し、前記パターンの最
小線幅が比較的大きな第１原板と前記パターンの最小線
幅が比較的小さな第２原板とが使用される際、該第１原
板を使用する場合には光源部が光軸近傍にある２次光源
が形成され、該第２原板を使用する場合には、前記光軸
を原点に直交座標を定めた時、光源部が前記直交座標の
４つの象限の夫々に独立して存する２次光源が使用され
ることを特徴とする投影露光装置。（イ−６）光源からの光で２次光源を形成し、該２次光
源からの光束により原板のパターンを照明する照明光学
系と、該照明されたパターンを基板上に投影する投影光
学系とを有する投影露光装置において、前記２次光源の
形状の変更に応じて前記投影光学系の少なくとも一つの
光学特性を調整する手段を有し、前記パターンの最小線
幅が比較的大きな第１原板と前記パターンの最小線幅が
比較的小さな第２原板とが使用される際、該第１原板を
使用する場合には光源部が光軸近傍にある２次光源が形
成され、該第２原板を使用する場合には、前記光軸を原
点に直交座標を定めた時、光源部が前記直交座標の４つ
の象限の夫々に独立して存する２次光源が使用されるこ
とを特徴とする投影露光装置。である。Further, the projection exposure apparatus of the present invention comprises: (a-1) an illumination optical system for forming a secondary light source with light from a light source, and illuminating a pattern on an original plate with a light beam from the secondary light source; In a projection exposure apparatus having a projection optical system for projecting an illuminated pattern onto a substrate, the shape of the secondary light source is changed independently of adjustment for correcting a change in optical characteristics of the projection optical system due to projection exposure. A projection exposure apparatus comprising means for adjusting at least one of a projection magnification, a symmetric distortion, a field curvature, a one-sided blur, and a tilt of the projection optical system according to (B-2) An illumination optical system that forms a secondary light source with light from a light source, and illuminates a pattern on an original plate with a light beam from the secondary light source, and a projection optical system that projects the illuminated pattern onto a substrate Means for correcting a change due to a change in the shape of the secondary light source of at least one of the projection magnification, symmetric distortion, field curvature, one-sided blur and pivotal inclination of the projection optical system. A projection exposure apparatus comprising: (B-3) An illumination optical system that forms a secondary light source with light from a light source, and illuminates a pattern on an original plate with a light beam from the secondary light source, and a projection optical system that projects the illuminated pattern onto a substrate Wherein the projection magnification of the projection optical system changes by changing the shape of the secondary light source,
A projection exposure apparatus comprising means for adjusting at least one of symmetric distortion, field curvature, one-sided blur, and pivotal inclination. (A-4) An illumination optical system that forms a secondary light source with light from a light source and illuminates a pattern on an original plate with a light beam from the secondary light source, and a projection optical system that projects the illuminated pattern onto a substrate A projection exposure apparatus having at least one optical characteristic of the projection optical system according to a change in the shape of the secondary light source, independently of adjustment for correcting a change in the optical characteristic of the projection optical system due to projection exposure. When a first original plate having a relatively small minimum line width of the pattern and a second original plate having a relatively small minimum line width of the pattern are used, the first original plate is used. In the case where a secondary light source having a light source unit near the optical axis is formed, and the second original plate is used, when the orthogonal coordinates are defined with the optical axis as the origin, the light source unit has four orthogonal coordinates. Secondary light sources that exist independently in each quadrant are used Projection exposure apparatus according to claim and. (A-5) An illumination optical system that forms a secondary light source with light from a light source and illuminates a pattern on an original plate with a light beam from the secondary light source, and a projection optical system that projects the illuminated pattern onto a substrate A projection exposure apparatus having means for correcting a change in at least one optical characteristic of the projection optical system due to a change in the shape of the secondary light source, wherein a first original plate having a relatively large minimum line width of the pattern is provided. When a second original plate having a relatively small minimum line width of the pattern is used, when the first original plate is used, a secondary light source having a light source section near the optical axis is formed, and the second original plate is formed. Is used, when orthogonal coordinates are determined with the optical axis as the origin, a secondary light source is used in which the light source unit independently exists in each of the four quadrants of the orthogonal coordinates. Exposure equipment. (B-6) An illumination optical system that forms a secondary light source with light from a light source, and illuminates a pattern on an original plate with a light beam from the secondary light source, and a projection optical system that projects the illuminated pattern onto a substrate And a means for adjusting at least one optical characteristic of the projection optical system in accordance with a change in the shape of the secondary light source, wherein the first original plate having a relatively large minimum line width of the pattern is provided. When a second original plate having a relatively small minimum line width of the pattern is used, when the first original plate is used, a secondary light source having a light source section near the optical axis is formed, and the second original plate is formed. Is used, when orthogonal coordinates are determined with the optical axis as the origin, a secondary light source is used in which the light source unit independently exists in each of the four quadrants of the orthogonal coordinates. Exposure equipment. It is.

【００２０】又、本発明の投影露光装置は前記投影光学
系の投影倍率や対称歪曲収差を調整するために前記原板
と前記投影光学系の間隔が調整されることや、前記投影
光学系の投影倍率や対称歪曲収差を調整するために前記
投影光学系の屈折力が調整されることや、前記２次光源
の形状の変更に応じて照度分布を調整することや、前記
原板に形成されたパターンの最小線幅に関する情報を前
記装置のコントローラーに入力する手段を備え、該コン
トローラーが該情報に応じて前記照明光学系の２次光源
の形状を調整すること等を特徴としている。In the projection exposure apparatus according to the present invention, the distance between the original plate and the projection optical system is adjusted in order to adjust the projection magnification and the symmetric distortion of the projection optical system. The refractive power of the projection optical system is adjusted to adjust magnification or symmetric distortion, or the illuminance distribution is adjusted according to a change in the shape of the secondary light source, or the pattern formed on the original plate Means for inputting information regarding the minimum line width to the controller of the apparatus, and the controller adjusts the shape of the secondary light source of the illumination optical system according to the information.

【００２１】[0021]

【実施例】図１は本発明の実施例１の要部概略図であ
る。図中１１は超高圧水銀灯等の光源でその発光点は楕
円ミラー１２の第１焦点近傍に配置している。この超高
圧水銀灯１１より発した光が楕円ミラー１２によって集
光される。１３は光路を曲げるためのミラー、１４はシ
ャッターで通過光量を制限している。１５はリレーレン
ズ系で超高圧水銀灯１１からの光を波長選択フィルター
１６を介してオプティカルインテグレータ１７に効率よ
く集めている。オプティカルインテグレータ１７は後述
するように複数の微小レンズを２次元的に配列した構成
より成っている。FIG. 1 is a schematic view of a main part of a first embodiment of the present invention. In the figure, reference numeral 11 denotes a light source such as an ultra-high pressure mercury lamp, the light emitting point of which is arranged near the first focal point of the elliptical mirror 12. The light emitted from the ultra-high pressure mercury lamp 11 is collected by the elliptical mirror 12. 13 is a mirror for bending the optical path, and 14 is a shutter for limiting the amount of light passing therethrough. Reference numeral 15 denotes a relay lens system which efficiently collects light from the ultra-high pressure mercury lamp 11 to an optical integrator 17 via a wavelength selection filter 16. The optical integrator 17 has a configuration in which a plurality of minute lenses are two-dimensionally arranged as described later.

【００２２】本実施例においてはオプティカルインテグ
レータ（インテグレータ）１７への結像状態はクリティ
カル照明でもケーラー照明でもよく、また例えば楕円ミ
ラー１２の射出口をオプティカルインテグレータ１７に
結像するものであっても良い。波長選択フィルター１６
は超高圧水銀灯１１からの光束の波長成分の中から必要
な波長成分の光のみを選択して通過させている。In this embodiment, the state of image formation on the optical integrator (integrator) 17 may be critical illumination or Koehler illumination, or, for example, an image of the exit of the elliptical mirror 12 may be formed on the optical integrator 17. . Wavelength selection filter 16
Selects only light of a necessary wavelength component from the wavelength components of the light flux from the ultrahigh pressure mercury lamp 11 and passes it.

【００２３】１８は選択手段としての絞り形状調整部材
であり、複数の絞りをターレット式に配置して構成して
おり、オプティカルインテグレータ１７の後に配置して
いる。絞り形状調整部材１８は駆動手段５０により回動
されオプティカルインテグレータ１７の形状に応じてオ
プティカルインテグレータ１７を構成する複数の微小レ
ンズから所定の微小レンズの選択を行なっている。即
ち、本実施例では絞り形状調整部材１８により露光を行
なう後述する半導体集積回路のパターン形状に合わせた
照明方法を選択している。このときの複数の微小レンズ
の選択に関しては後述する。Reference numeral 18 denotes a diaphragm shape adjusting member as a selecting means, which is constituted by arranging a plurality of diaphragms in a turret type, and is arranged after the optical integrator 17. The diaphragm shape adjusting member 18 is rotated by the driving means 50 and selects a predetermined minute lens from a plurality of minute lenses constituting the optical integrator 17 according to the shape of the optical integrator 17. That is, in the present embodiment, an illumination method suitable for a pattern shape of a later-described semiconductor integrated circuit in which exposure is performed by the aperture shape adjusting member 18 is selected. The selection of the plurality of micro lenses at this time will be described later.

【００２４】１９は光路を曲げるためのミラー、２０は
レンズ系であり、絞り形状調整部材１８を通過した光束
を集光している。レンズ系２０は照明の均一性をコント
ロールするために重要な役割を果している。２１はハー
フミラーであり、レンズ系２０からの光束を透過光と反
射光に分割している。このうちハーフミラー２１で反射
した光はレンズ３８、ピンホール３９を介してフォトデ
ィテクター４０に導光している。ピンホール３９は露光
が行なわれるべきパターンを持ったレチクル３０と光学
的に等価な位置にあり、ここを通過した光がフォトディ
テクター４０によって検出して、露光量のコントロール
を行なっている。Reference numeral 19 denotes a mirror for bending the optical path, and reference numeral 20 denotes a lens system, which collects a light beam that has passed through the diaphragm shape adjusting member 18. The lens system 20 plays an important role in controlling illumination uniformity. Reference numeral 21 denotes a half mirror, which divides a light beam from the lens system 20 into transmitted light and reflected light. The light reflected by the half mirror 21 is guided to a photodetector 40 via a lens 38 and a pinhole 39. The pinhole 39 is located at a position optically equivalent to the reticle 30 having a pattern to be exposed, and the light passing therethrough is detected by the photodetector 40 to control the amount of exposure.

【００２５】２２は所謂マスキングを行なうメカニカル
ブレードであり、レチクル３０の露光されるべきパター
ン部の大きさによって駆動系（不図示）によって位置の
調整を行なっている。２３はミラー、２４はレンズ系、
２５はミラー、２６はレンズ系で、これらの各部材を介
した超高圧水銀灯１１からの光でレチクルステージ３７
上に載置されたレチクル３０を照明している。Reference numeral 22 denotes a mechanical blade for performing so-called masking, and the position of the reticle 30 is adjusted by a drive system (not shown) according to the size of a pattern portion to be exposed. 23 is a mirror, 24 is a lens system,
Reference numeral 25 denotes a mirror, and reference numeral 26 denotes a lens system. The reticle stage 37 receives light from the ultra-high pressure mercury lamp 11 through these members.
The reticle 30 placed above is illuminated.

【００２６】３１は投影光学系であり、レチクル３０上
のパターンをウェハー３２に投影結像させている。ウェ
ハー３２はウェハーチャック３３に吸着しており、更に
ウエハーチャック３３はレーザー干渉計３６によって制
御されるステージ３４上に載置している。尚、３５はミ
ラーであり、ウェハーステージ３４上に載置しており、
あるレーザー干渉計（不図示）からの光を反射させてい
る。A projection optical system 31 projects and forms a pattern on the reticle 30 onto a wafer 32. The wafer 32 is attracted to a wafer chuck 33, and the wafer chuck 33 is mounted on a stage 34 controlled by a laser interferometer 36. A mirror 35 is mounted on the wafer stage 34.
Light from a certain laser interferometer (not shown) is reflected.

【００２７】本実施例においてオプティカルインテグレ
ータ１７の射出面１７ｂは各要素１９，２０，２３，２
４，２５，２６を介して投影光学系３１の瞳面３１ａと
略共役関係と成っている。即ち投影光学系３１の瞳面３
１ａに射出瞳１７ｂ、即ち絞り形状調整部材１８に相当
する有効光源像が形成している。In the present embodiment, the exit surface 17b of the optical integrator 17 is connected to each of the elements 19, 20, 23, 2
The pupil plane 31a of the projection optical system 31 is substantially conjugated with the pupil plane 31a via 4, 25, and 26. That is, the pupil plane 3 of the projection optical system 31
An effective light source image corresponding to the exit pupil 17b, that is, the aperture shape adjusting member 18, is formed at 1a.

【００２８】次に図２を用いて投影光学系３１の瞳面３
１ａとオプティカルインテグレータ１７の射出面１７ｂ
との関係について説明する。オプティカルインテグレー
タ１７の形状は投影光学系３１の瞳面３１ａに形成され
る有効光源の形状に対応している。図２はこの様子を示
したもので、投影光学系３１の瞳面３１ａに形成される
射出面１７ｂの有効光源像１７ｃの形状が重ね描きされ
ている。正規化するため投影光学系３１の瞳３１ａの径
を１．０としており、この瞳３１ａ中にオプティカルイ
ンテグレータ１７を構成する複数の微小レンズが結像し
て有効光源像１７ｃを形成している。本実施例の場合オ
プティカルインテグレータを構成する個々の微小レンズ
は正方形の形状をしている。Next, the pupil plane 3 of the projection optical system 31 will be described with reference to FIG.
1a and emission surface 17b of optical integrator 17
Will be described. The shape of the optical integrator 17 corresponds to the shape of the effective light source formed on the pupil plane 31a of the projection optical system 31. FIG. 2 shows this state, in which the shape of the effective light source image 17c of the exit surface 17b formed on the pupil surface 31a of the projection optical system 31 is overlaid. For normalization, the diameter of the pupil 31a of the projection optical system 31 is set to 1.0, and a plurality of minute lenses forming the optical integrator 17 form an image in the pupil 31a to form an effective light source image 17c. In the case of the present embodiment, each minute lens constituting the optical integrator has a square shape.

【００２９】ここで半導体集積回路のパターンを設計す
るときに用いられる主たる方向となる直交軸をｘおよび
ｙ軸に取る。この方向はレチクル３０上に形成されてい
るパターンの主たる方向と一致した方向であり、正方形
の形状をしているレチクル３０の外形の方向とほぼ一致
している。Here, the orthogonal axes which are the main directions used when designing the pattern of the semiconductor integrated circuit are taken as x and y axes. This direction coincides with the main direction of the pattern formed on the reticle 30, and substantially coincides with the direction of the outer shape of the reticle 30 having a square shape.

【００３０】高解像力の照明系が威力を発揮するのは先
に述べたｋ₁ ファクターが０．５付近の値を取るときで
ある。The illumination system with high resolution exerts its power when the aforementioned k ₁ factor takes a value near 0.5.

【００３１】そこで本実施例では絞り形状調整部材１８
の絞りによりオプティカルインテグレータ１７を構成す
る複数の微小レンズのうちからレチクル３０面上のパタ
ーン形状に応じて所定の微小レンズを通過する光束のみ
をレチクル３０の照明用として用いるようにしている。Therefore, in this embodiment, the aperture shape adjusting member 18 is used.
Of the plurality of micro lenses constituting the optical integrator 17 by the aperture, only a light beam passing through a predetermined micro lens according to the pattern shape on the reticle 30 surface is used for illumination of the reticle 30.

【００３２】具体的には投影光学系３１の瞳面３１ａ上
で中心領域以外の複数の領域を光束が通過するように微
小レンズを選択している。More specifically, a micro lens is selected so that a light beam passes through a plurality of regions other than the center region on the pupil plane 31a of the projection optical system 31.

【００３３】図３（Ａ）、（Ｂ）はオプティカルインテ
グレータ１７を構成する複数の微小レンズのうち絞り形
状調整部材１８の絞りにより所定の微小レンズを通過す
る光束のみを選択したときを示す瞳面３１ａ上における
概略図である。同図において黒く塗りつぶした領域は光
が遮光され白い領域は光が通過してくる領域を示してい
る。FIGS. 3A and 3B show a pupil plane when only a light beam passing through a predetermined minute lens is selected by the stop of the stop shape adjusting member 18 from among a plurality of minute lenses constituting the optical integrator 17. It is the schematic on 31a. In the same drawing, a black-out area indicates a light-shielded area, and a white area indicates an area through which the light passes.

【００３４】図３（Ａ）はパターンで解像度が必要とさ
れる方向がｘおよびｙ方向であるときに対する瞳面３１
ａ上の有効光源像を示している。瞳面３１ａを表わす円
をｘ² ＋ｙ² ＝１としたとき、次の４つの円を考える。FIG. 3A shows the pupil plane 31 when the directions in which resolution is required in the pattern are the x and y directions.
5 shows an effective light source image on a. Assuming that a circle representing the pupil plane 31a is x ² + y ² = 1, the following four circles are considered.

【００３５】（ｘー１）² ＋ｙ² ＝１ｘ² ＋（ｙー１）² ＝１（ｘ＋１）² ＋ｙ² ＝１ｘ² ＋（ｙ＋１）² ＝１これらの４つの円によって瞳面３１ａを表わす円は領域
１０１〜１０８までの８つの領域に分解される。(X-1) ² + y ² = 1 x ² + (y-1) ² = 1 (x + 1) ² + y ² = 1 x ² + (y + 1) ² = 1 The pupil plane 31a is defined by these four circles. Is decomposed into eight regions 101 to 108.

【００３６】本実施例でｘおよびｙ方向に対して高解像
で深度の深い照明系は、これらのうちから偶数の領域、
即ち領域１０２，１０４，１０６，１０８に存在する微
小レンズ群に優先的に光を通すように選択することによ
って達成している。原点であるｘ＝０，ｙ＝０付近の微
小レンズは主として粗いパターンの深度向上に効果が大
きいため、中心付近の部分を選ぶか否かは焼き付けよう
とするパターンによって定まる選択事項である。In the present embodiment, the illumination system having a high resolution and a deep depth in the x and y directions includes an even number area,
That is, this is achieved by selecting the microlens groups existing in the regions 102, 104, 106, and 108 so as to transmit light preferentially. Since the microlens near x = 0 and y = 0, which is the origin, is largely effective in improving the depth of a coarse pattern, whether or not to select a part near the center is a choice determined by the pattern to be printed.

【００３７】図３（Ａ）の例では中心付近の微小レンズ
は除外した例が示してある。尚、オプテイカルインテグ
レータ１７の外側の部分は照明系内でインテグレータ保
持部材（不図示）によって遮光されている。又図３
（Ａ），（Ｂ）では遮光するべき微小レンズと投影レン
ズの瞳３１ａとの関係を分かり易くするため瞳３１ａと
オプティカルインテグレータの有効光源像１７ｃが重ね
描きしている。FIG. 3A shows an example in which the micro lens near the center is excluded. The outside portion of the optical integrator 17 is shielded from light by an integrator holding member (not shown) in the illumination system. FIG. 3
7A and 7B, the pupil 31a and the effective light source image 17c of the optical integrator are overlaid in order to make it easy to understand the relationship between the microlens to be shielded and the pupil 31a of the projection lens.

【００３８】これに対し図３（Ｂ）は±４５°方向のパ
ターンに対して高解像が必要とされる場合の絞りの形状
を示す。図３（Ａ）の場合と同じく瞳３１ａとオプティ
カルインテグレータ１７の有効光源像１７ｃとの関係を
図示している。±４５°パターンの場合には前と同じと
してOn the other hand, FIG. 3B shows the shape of the stop when high resolution is required for a pattern in the ± 45 ° direction. 3A illustrates the relationship between the pupil 31a and the effective light source image 17c of the optical integrator 17 as in the case of FIG. Same as before for ± 45 ° pattern

【００３９】[0039]

【数１】なる４つの円を、瞳３１ａに対して重ね描きして図３
（Ａ）の場合と同じく瞳３１ａを領域１１１〜１１８の
８つの領域に区分する。この場合±４５°方向のパター
ンの高解像化に寄与するのは今度は奇数で表わされた領
域、即ち領域１１１，１１３，１１５，１１７である。
この領域に存在しているオプティカルインテグレータ１
７の微小レンズを優先的に選択することにより±４５°
方向のパターンはｋ₁ ファクターが０．５付近で焦点深
度が著しく増大する。(Equation 1) The four circles shown in FIG.
As in the case of (A), the pupil 31a is divided into eight regions 111 to 118. In this case, the regions represented by odd numbers, that is, the regions 111, 113, 115, and 117 contribute to the high resolution of the pattern in the ± 45 ° direction.
Optical integrator 1 existing in this area
± 45 ° by preferentially selecting 7 microlenses
The directional pattern has a significant increase in the depth of focus when the k ₁ factor is around 0.5.

【００４０】図４は絞り形状調整部材１８の各絞り１８
ａ〜１８ｄの切り換えを行なう概略図である。図４に示
すようにターレット式の交換方式を採用している。第１
の絞り１８ａは、ｋ₁ で１以上のそれほど細かくないパ
ターンを焼きつける場合に用いられる。第１の絞り１８
ａはこれまで公知の従来型の照明光学系の構成と同じで
あり、必要に応じてオプティカルインテグレータ１７を
構成する微小レンズ群の外側の部分を遮光する様にも設
定される固定の絞りである。絞り１８ｂ〜１８ｄは本実
施例のレチクルのパターンの種類に従う種々の絞りであ
る。FIG. 4 shows each stop 18 of the stop shape adjusting member 18.
It is the schematic which performs switching of a-18d. As shown in FIG. 4, a turret type exchange system is employed. First
The aperture 18a, used when burning one or more is not so fine pattern in k _1. First diaphragm 18
Reference numeral a denotes a fixed stop which has the same configuration as that of a conventionally known illumination optical system, and which is set so as to shield a portion outside the minute lens group constituting the optical integrator 17 as necessary. . The diaphragms 18b to 18d are various diaphragms according to the type of the reticle pattern of the present embodiment.

【００４１】このように本実施例では光軸を原点と直交
座標を定めた時、前記光軸外に形成される２次光源が該
直交座標の４つの象限の夫々に独立した光源部分を有す
るようにしている。As described above, in this embodiment, when the optical axis is defined by the origin and the orthogonal coordinates, the secondary light source formed outside the optical axis has an independent light source portion in each of the four quadrants of the orthogonal coordinates. Like that.

【００４２】又、本実施例において前記原板として回路
パターンの最小線幅が比較的大きな第１原板と回路パタ
ーンの最小線幅が比較的小さな第２原板とが使用され、
該第１原板を使用する場合には図４の開口１８ａの如く
前記２次光源が光軸近傍に形成され、該第２原板を使用
する場合には前記２次光源が図４の開口１８ｂ，１８
ｃ，１８ｄの如く光軸外に形成されるようにしている。In this embodiment, a first original plate having a relatively large minimum line width of the circuit pattern and a second original plate having a relatively small minimum line width of the circuit pattern are used as the original plate.
When the first original plate is used, the secondary light source is formed near the optical axis as in the opening 18a of FIG. 4, and when the second original plate is used, the secondary light source is formed by the openings 18b and 18b of FIG. 18
c, 18d, it is formed off the optical axis.

【００４３】この他、２次光源が光軸外に形成される形
態としては例えば円形のリング状や矩形のリング状等が
適用可能である。In addition, as a form in which the secondary light source is formed off the optical axis, for example, a circular ring shape or a rectangular ring shape can be applied.

【００４４】この他、一般的な傾向として高解像用の照
明系の場合、オプテイカルインテグレータ１７は従来の
照明系で必要とされる大きさより、瞳面上でより外側の
領域まで使う方が高空間周波数に対し有利である。例え
ば従来の照明系では半径０．５以内の微小レンズ群を使
うことが好ましいのに対し、高解像用の照明系の場合に
は中心部の微小レンズは使用しないものの、例えば最大
半径０．７５以内の円の中ににある微小レンズ群まで使
用する方が好ましいことがある。In addition, as a general tendency, in the case of an illumination system for high resolution, it is better to use the optical integrator 17 up to a region outside the pupil plane than the size required in the conventional illumination system. Advantageous for high spatial frequencies. For example, in a conventional illumination system, it is preferable to use a microlens group having a radius of 0.5 or less, whereas in a high-resolution illumination system, a microlens at the center is not used. It may be preferable to use up to a minute lens group within a circle within 75.

【００４５】このためオプテイカルインテグレータ１７
の大きさ、及び、照明系のその他の部分の有効径は、予
め従来型と高解像型の両者を考慮して設定しておくこと
が好ましい。また、オプテイカルインテグレータ１７の
入射口１７ａにおける光の強度分布も、絞りが挿入され
ても十分機能が果たせるような大きさを持っていること
が好ましい。絞り１８ａで外側の微小レンズ群を遮光す
る場合があるのは以上のような理由からで、例えばオプ
ティカルインテグレータ１７としては半径０．７５のと
ころまで用意しておいても、絞り１８ａではそのうちか
ら半径０．５以内の部分を選ぶといったことが行なわれ
る。For this reason, the optical integrator 17
And the effective diameter of the other parts of the illumination system are preferably set in advance in consideration of both the conventional type and the high-resolution type. Further, it is preferable that the light intensity distribution at the entrance 17a of the optical integrator 17 also has such a size that the function can be sufficiently performed even when a stop is inserted. For the reasons described above, the aperture 18a may shield the outer minute lens group from light. For example, even if the optical integrator 17 is prepared up to a radius of 0.75, the aperture 18a may have a radius smaller than that. For example, a part within 0.5 is selected.

【００４６】以上示したように露光を行なうべき半導体
集積回路のパターンの特殊性を考慮したうえで絞りの形
状を決定すれば、パターンに応じた最適の露光装置を構
成することができる。これらの絞りの選択は例えば露光
装置全体の後述する制御コンピュータ（制御部５４）か
ら与えて、自動的に行なっている。図４に示したのはこ
のような絞りを搭載した絞り形状調整部材１８の一例
で、この場合には４種類の絞り１８ａ〜１８ｄのパター
ンを選択することが可能である。勿論この数はもっとふ
やすことも容易である。As described above, if the shape of the stop is determined in consideration of the specificity of the pattern of the semiconductor integrated circuit to be exposed, an optimal exposure apparatus according to the pattern can be constructed. These apertures are selected automatically from, for example, a control computer (control unit 54) described later of the entire exposure apparatus. FIG. 4 shows an example of the aperture shape adjusting member 18 equipped with such an aperture. In this case, it is possible to select four types of aperture 18a to 18d patterns. Of course, this number can easily be increased.

【００４７】絞りを選択したとき、絞りの選択に従って
照度むらが変化する場合がある。そこで本実施例ではこ
のような場合の照度むらをレンズ系２０を調整して微調
を行なっている。照度むらの微調については、レンズ系
２０を構成する個々の要素レンズの光軸方向の間隔で調
整可能であることが既に本出願人の先の出願によって示
されている。５１は駆動機構であり、レンズ系２０の要
素レンズを駆動させている。レンズ系２０の調整は絞り
の選択に応じて行なっている。また場合によっては絞り
の形状の変更に応じてレンズ系２０自体をそっくり交換
するようにすることも可能である。そのような場合には
レンズ系２０に相当するレンズ系を複数個用意し、絞り
の形状の選択に従ってターレット式に交換されるように
レンズ系を入れ替えている。When the aperture is selected, the illuminance unevenness may change according to the selection of the aperture. Therefore, in this embodiment, the illuminance unevenness in such a case is finely adjusted by adjusting the lens system 20. It has already been shown by the applicant of the present application that the fine adjustment of the illuminance unevenness can be adjusted at intervals in the optical axis direction of the individual element lenses constituting the lens system 20. A driving mechanism 51 drives the element lenses of the lens system 20. The adjustment of the lens system 20 is performed according to the selection of the aperture. In some cases, it is also possible to completely replace the lens system 20 itself according to a change in the shape of the stop. In such a case, a plurality of lens systems corresponding to the lens system 20 are prepared, and the lens systems are exchanged so as to be changed to a turret type according to the selection of the shape of the diaphragm.

【００４８】以上のように本実施例では、絞りの形状を
変更することによって半導体集積回路のパターンの特徴
に応じた照明系を選択している。また本実施例の場合、
高解像用の照明系にした場合、大きく有効光源全体を見
ると光源自体が４つの領域に別れることが特徴となって
いる。この場合の重要要素はこの４つの領域の強度のバ
ランスである。しかしながら図１のような系だと超高圧
水銀灯１１のケーブルの影がこのバランスに悪影響を与
える場合がある。従って、図３に示した絞りを用いる高
解像用の照明系ではケーブルの影になる線状の部分をオ
プティカルインテグレータ１７で遮光する微小レンズの
位置と対応するようにセットさせることが望ましい。As described above, in this embodiment, the illumination system according to the feature of the pattern of the semiconductor integrated circuit is selected by changing the shape of the stop. In the case of this embodiment,
When an illumination system for high resolution is used, the light source itself is divided into four regions when the entire effective light source is viewed largely. The important factor in this case is the balance between the intensity of these four regions. However, in the system as shown in FIG. 1, the shadow of the cable of the ultra-high pressure mercury lamp 11 may adversely affect this balance. Therefore, in the illumination system for high resolution using the aperture shown in FIG. 3, it is desirable to set the linear portion which becomes the shadow of the cable so as to correspond to the position of the minute lens which is shielded by the optical integrator 17.

【００４９】即ち、図３（Ａ）の絞りの場合で言えば図
５（Ａ）に示す様にケーブル１１ａを引っ張る方向はｘ
またはｙ方向にセットすることが好ましく、図３（Ｂ）
の絞りを使用した場合のケーブル１１ａを引っ張る方向
は図５（Ｂ）に示す様にｘ及びｙ方向に対して±４５°
にセットすることが好ましい。本実施例では超高圧水銀
灯のケーブルを引っ張る方向も、絞りの変更に対応して
変えることが好ましい。That is, in the case of the diaphragm of FIG. 3A, the direction of pulling the cable 11a is x as shown in FIG. 5A.
Alternatively, it is preferable to set in the y direction.
5B, the direction in which the cable 11a is pulled is ± 45 ° with respect to the x and y directions as shown in FIG.
Is preferably set to. In this embodiment, it is preferable that the direction in which the cable of the ultrahigh pressure mercury lamp is pulled is also changed in accordance with the change of the aperture.

【００５０】尚、図１の５２，５３は各々ウエハ３２の
面位置（光軸３１ｂ方向）を検出する為の投光系と受光
系である。Reference numerals 52 and 53 in FIG. 1 denote a light projecting system and a light receiving system for detecting the surface position of the wafer 32 (in the direction of the optical axis 31b).

【００５１】投光系５２からの光はウエハ３２面上にス
ポット光を形成する。ウエハ３２で反射した光は受光系
５３のポジションセンサーに入射し、光源像を結像して
いる。The light from the light projecting system 52 forms a spot light on the surface of the wafer 32. The light reflected by the wafer 32 enters the position sensor of the light receiving system 53 and forms a light source image.

【００５２】即ち、同図に示すウエハ３２の面位置検出
においてはウエハ３２の面上の光束の反射点と受光系５
３からのポジションセンサー上の入射点とを結像関係と
なるようにし、ウエハ３２の上下方向の位置ずれ量をポ
ジションセンサー上の光束の入射位置より検出してい
る。That is, in detecting the position of the surface of the wafer 32 shown in FIG.
An incident point on the position sensor from No. 3 is formed into an imaging relationship, and the amount of vertical displacement of the wafer 32 is detected from the incident position of the light beam on the position sensor.

【００５３】本実施例では第１物体面（レチクル）３０
上のパターンを投影光学系３１により第２物体面（ウエ
ハ）３２上に投影露光する際、第１物体面上のパターン
形状に対応させて複数の微小レンズを２次元的に配列し
たオプティカルインテグレータ１７の複数の微小レンズ
のうちから例えば図３（Ａ），（Ｂ）に示すように所定
の微小レンズを通過する光束を選択している。In this embodiment, the first object plane (reticle) 30
When the upper pattern is projected and exposed on the second object plane (wafer) 32 by the projection optical system 31, the optical integrator 17 in which a plurality of minute lenses are two-dimensionally arranged in correspondence with the pattern shape on the first object plane. For example, as shown in FIGS. 3A and 3B, a light beam passing through a predetermined minute lens is selected from the plurality of minute lenses.

【００５４】即ち、該投影光学系の瞳面上で例えば図４
で示す開口の領域を光束が通過するようにし、該領域を
通過するような光束で該第１物体面上のパターンを照明
している。That is, on the pupil plane of the projection optical system, for example, FIG.
The light flux is made to pass through the area of the opening indicated by the symbol, and the pattern on the first object plane is illuminated with the light flux passing through the area.

【００５５】次にこのときの投影光学系の使用態様の違
いにより光学特性、例えば歪曲収差や倍率変化等の作用
の違いのうち少なくとも１つを調整する方法について説
明する。Next, a method of adjusting at least one of optical characteristics, for example, a difference in operation such as distortion and a change in magnification, according to a difference in usage of the projection optical system at this time will be described.

【００５６】本実施例では投影光学系３１の光学特性の
調整をマイクロプロセッサーから成る制御部５４を中心
に行なっている。制御部５４は例えば次のような機能を
有している。In this embodiment, the adjustment of the optical characteristics of the projection optical system 31 is performed mainly by the control unit 54 composed of a microprocessor. The control unit 54 has, for example, the following functions.

【００５７】（イ）レチクル３０の照明方法を絞り形状
調整部材１８を駆動させる駆動手段５０からの信号に基
づいて検出している。(A) The illumination method of the reticle 30 is detected based on a signal from the driving means 50 for driving the aperture shape adjusting member 18.

【００５８】（ロ）照明方法を検出することにより投影
光学系３１の使用態様による光学特性の変化、例えば歪
曲収差や倍率誤差等を後述するように演算し求めてい
る。そしてこのときの歪曲収差や倍率誤差等の光学特性
の変化を例えば投影光学系３１のレチクル３０に近いレ
ンズ５６を駆動手段５７によって光軸上移動させたり、
又はレチクル位置検出手段６５からの信号を利用して駆
動手段６６によりレチクル３０の位置を駆動させたりし
て調整している。(B) By detecting the illumination method, a change in optical characteristics due to the usage of the projection optical system 31, such as a distortion or a magnification error, is calculated and obtained as described later. At this time, changes in optical characteristics such as distortion and magnification error can be determined by, for example, moving the lens 56 of the projection optical system 31 close to the reticle 30 on the optical axis by the driving unit 57,
Alternatively, the position of the reticle 30 is adjusted by driving the position of the reticle 30 by the driving unit 66 using a signal from the reticle position detecting unit 65.

【００５９】（ハ）気圧センサー６１、温度センサー６
２、湿度センサー６３からの信号及びレンズ温度センサ
ー６４からの信号に基づいて投影光学系３１のピント位
置変動や倍率変化等を予め記憶した式及び係数等を用い
て演算し求めている。そしてこのときの変化量を例えば
駆動手段５５によりステージ３４を光軸３１ｂ方向に移
動させて補正している。(C) Barometric pressure sensor 61, temperature sensor 6
2. Based on the signal from the humidity sensor 63 and the signal from the lens temperature sensor 64, the focus position fluctuation and the magnification change of the projection optical system 31 are calculated and calculated by using an equation and a coefficient stored in advance. The amount of change at this time is corrected by, for example, moving the stage 34 in the direction of the optical axis 31b by the driving means 55.

【００６０】次に本実施例において表−１に示す数値よ
り成る投影光学系を用いたときの光学特性の調整方法の
具体例について説明する。図７に表−１の投影光学系の
レンズ断面図を示す。Next, a specific example of a method for adjusting optical characteristics when a projection optical system having the numerical values shown in Table 1 is used in this embodiment will be described. FIG. 7 shows a lens sectional view of the projection optical system shown in Table 1.

【００６１】まず表−２にレチクル３０と投影光学系３
１との間隔Ｓ１、及び各レンズ間隔Ｌ１〜Ｌ１３を個別
に１ｍｍ変化させたときのウエハ２面上の像高１０ｍｍ
の位置における対称歪曲収差の変化量（ΔＳＤ）、投影
倍率の変化量（Δβ）、これらの比（ΔＳＤ／Δβ）、
像高の変化量（Δｙ）、片ボケの変化量ΔＡｙ、ピボタ
ル傾きの変化量ΔＰを示す。First, Table 2 shows the reticle 30 and the projection optical system 3.
10 and an image height of 10 mm on the surface of the wafer 2 when the lens distances L1 to L13 are individually changed by 1 mm.
, The change amount of the symmetric distortion at the position (ΔSD), the change amount of the projection magnification (Δβ), their ratio (ΔSD / Δβ),
The change amount (Δy) of the image height, the change amount ΔAy of the one-sided blur, and the change amount ΔP of the pivotal inclination are shown.

【００６２】本実施例ではこのようにレンズ間隔を変化
させたときの光学特性の変動を予め求めておき、照明方
法を種々と変えたときの投影光学系の使用態様の違いに
よる生じる光学特性の変化を調整している。In this embodiment, the variation of the optical characteristics when the lens interval is changed is obtained in advance, and the optical characteristics caused by the difference in the usage of the projection optical system when the illumination method is variously changed. Adjusting for changes.

【００６３】表−１ R 1= 223.62 D 1= 15.00 N 1= 1.52113 R 2= -3002.34 D 2= 198.58 R 3= 447.09 D 3= 8.00 N 2= 1.52113 R 4= 120.41 D 4= 6.85 R 5= 1361.15 D 5= 8.00 N 3= 1.52113 R 6= 116.03 D 6= 60.00 R 7= 233.10 D 7= 24.00 N 4= 1.52113 R 8= -194.78 D 8= 1.00 R 9= 183.54 D 9= 20.00 N 5= 1.52113 R10= -539.45 D10= 30.00 R11= 68.35 D11= 27.00 N 6= 1.52113 R12= 49.48 D12= 55.00 R13= -74.38 D13= 12.00 N 7= 1.52113 R14= 121.20 D14= 30.00 R15= -36.94 D15= 20.00 N 8= 1.52113 R16= -53.05 D16= 1.00 R17= -664.38 D17= 18.00 N 9= 1.52113 R18= -89.10 D18= 1.00 R19= 358.30 D19= 16.50 N10= 1.52113 R20= -215.20 D20= 1.00 R21= 122.34 D21= 18.50 N11= 1.52113 R22= 608.00 D22= 1.00 R23= 68.11 D23= 20.00 N12= 1.52113 R24= 103.07 D24= 73.14 表−１においてＲｉはレチクル側より数えて第ｉ番目の
レンズ面の曲率半径、Ｄｉはｉ番目のレンズ厚又は空気
間隔、Ｎｉはｉ番目のレンズの材質の屈折率である。Table 1 R 1 = 223.62 D 1 = 15.00 N 1 = 1.52113 R 2 = -3002.34 D 2 = 198.58 R 3 = 447.09 D 3 = 8.00 N 2 = 1.52113 R 4 = 120.41 D 4 = 6.85 R 5 = 1361.15 D 5 = 8.00 N 3 = 1.52113 R 6 = 116.03 D 6 = 60.00 R 7 = 233.10 D 7 = 24.00 N 4 = 1.52113 R 8 = -194.78 D 8 = 1.00 R 9 = 183.54 D 9 = 20.00 N 5 = 1.52113 R10 = -539.45 D10 = 30.00 R11 = 68.35 D11 = 27.00 N 6 = 1.52113 R12 = 49.48 D12 = 55.00 R13 = -74.38 D13 = 12.00 N 7 = 1.52113 R14 = 121.20 D14 = 30.00 R15 = -36.94 D15 = 20.00 N 8 = 1.52113 R16 = -53.05 D16 = 1.00 R17 = -664.38 D17 = 18.00 N 9 = 1.52113 R18 = -89.10 D18 = 1.00 R19 = 358.30 D19 = 16.50 N10 = 1.52113 R20 = -215.20 D20 = 1.00 R21 = 122.34 D21 = 18.50 N11 = 1.52113 R22 = 608.00 D22 = 1.00 R23 = 68.11 D23 = 20.00 N12 = 1.52113 R24 = 103.07 D24 = 73.14 In Table 1, Ri is the radius of curvature of the ith lens surface counted from the reticle side, and Di is the ith lens thickness. Alternatively, Ni is the refractive index of the material of the i-th lens.

【００６４】表−２Table 2

【００６５】[0065]

【表１】 [Table 1]

【００６６】[0066]

【表２】次に本実施例における光学特性の調整方法の具体例につ
いて説明する。今、照明方法として図３と同様に表わし
たとき図６（Ａ）に示すように直交座標の４つの象限に
各々独立した光源部分を有する照明法１と図６（Ｂ）に
示す従来のように光軸近傍のみに光源部分を有する照明
法２とを用いた場合を例にとる。[Table 2] Next, a specific example of a method for adjusting optical characteristics in the present embodiment will be described. Now, when the illumination method is represented in the same manner as in FIG. 3, as shown in FIG. 6 (A), the illumination method 1 has independent light source portions in four quadrants of rectangular coordinates, and the conventional method shown in FIG. 6 (B). An example in which the illumination method 2 having a light source portion only near the optical axis is used.

【００６７】このときの投影光学系３１の倍率誤差、歪
曲誤差、像面湾曲が照明法により以下のように変化し
た。これはウエハ面上での像高１０ｍｍの位置における
ものである。At this time, the magnification error, distortion error, and field curvature of the projection optical system 31 changed as follows by the illumination method. This is at a position with an image height of 10 mm on the wafer surface.

【００６８】[0068]

【表３】ここで表−２のデータを用いて、倍率誤差、歪曲誤差、
像面湾曲、片ボケとピボタル傾きを補正する。[Table 3] Here, using the data in Table 2, magnification error, distortion error,
Corrects field curvature, one-sided blur, and pivotal tilt.

【００６９】今、間隔Ｓ１の変化量をΔＳ１、間隔Ｌ１
の変化量をΔＬ１、間隔Ｌ３の変化量をΔＬ３、間隔Ｌ
５の変化量をΔＬ５、間隔Ｌ８の変化量をΔＬ８とする
と、歪曲誤差ΔＳＤ、倍率誤差ΔＢ、像面湾曲ΔＹ、片
ボケΔＡＹとピボタル傾きΔＰは各々次式となる。Now, the change amount of the interval S1 is ΔS1, the interval L1
ΔL1, the change amount of the interval L3 is ΔL3, the interval L3.
Assuming that the change amount of No. 5 is ΔL5 and the change amount of the interval L8 is ΔL8, the distortion error ΔSD, the magnification error ΔB, the field curvature ΔY, the one-sided blur ΔAY, and the pivotal inclination ΔP are expressed by the following equations.

【００７０】 ΔＳＤ＝０．７７×ΔＳ１＋１．０８×ΔＬ１＋４．４０×ΔＬ３ −０．３２×ΔＬ５＋０．５８×ΔＬ８ ΔＢ＝ −２０．０×ΔＬ１＋２０．０×ΔＬ３＋４５．０×ΔＬ５−９０．０×ΔＬ８ ΔＹ＝−０．１０×ΔＳ１−０．１０×ΔＬ１−２２．７×ΔＬ３＋７．６０×ΔＬ５＋３８．１×ΔＬ８ ΔＰ＝０．１８×ΔＳ１＋０．１２×ΔＬ１−１．７１×ΔＬ３ −０．５０×ΔＬ５−１０．２×ΔＬ８ ΔＳＤ＝−０．０２×ΔＳ１−０．１９×ΔＬ１＋７．０１×ΔＬ３ −２．０９×ΔＬ５＋０．１３×ΔＬ８照明法１から照明法２に切り替える場合を考える。ΔSD = 0.77 × ΔS1 + 1.08 × ΔL1 + 4.40 × ΔL3−0.32 × ΔL5 + 0.58 × ΔL8 ΔB = -20.0 × ΔL1 + 20.0 × ΔL3 + 45.0 × ΔL5-90.0 × ΔL8 ΔY = −0.10 × ΔS1−0.10 × ΔL1-22.7 × ΔL3 + 7.60 × ΔL5 + 38.1 × ΔL8 ΔP = 0.18 × ΔS1 + 0.12 × ΔL1-1.71 × ΔL3-0. 50 × ΔL5-10.2 × ΔL8 ΔSD = −0.02 × ΔS1−0.19 × ΔL1 + 7.01 × ΔL3−2.09 × ΔL5 + 0.13 × ΔL8 Consider a case where the illumination method 1 is switched to the illumination method 2.

【００７１】片ボケΔＡＹとピボタル傾き変化ΔＰを０
とし、上表の諸量の差、歪曲誤差ΔＳＤ、倍率誤差Δ
Ｂ、像面湾曲ΔＹを補正するためには、以下の式よりΔ
Ｓ１，ΔＬ１，ΔＬ３，ΔＬ５，ΔＬ８を未知数として
解けばよい。The one-sided blur ΔAY and the pivotal inclination change ΔP are set to 0.
And the difference between the quantities in the above table, distortion error ΔSD, magnification error Δ
B, to correct the field curvature ΔY, Δ
S1, ΔL1, ΔL3, ΔL5, and ΔL8 may be solved as unknowns.

【００７２】 ΔＳＤ＝０．７７×ΔＳ１＋１．０８×ΔＬ１＋４．４０×ΔＬ３ −０．３２×ΔＬ５＋０．５８×ΔＬ８＝０．２ ΔＢ＝ −２０．０×ΔＬ１＋２０．０×ΔＬ３＋４５．０×ΔＬ５−９０．０×ΔＬ８＝０．３ ΔＹ＝−０．１０×ΔＳ１−０．１０×ΔＬ１−２２．７×ΔＬ３＋７．６０×ΔＬ５＋３８．１×ΔＬ８＝１．０ ΔＰ＝０．１８×ΔＳ１＋０．１２×ΔＬ１−１．７１×ΔＬ３ −０．５０×ΔＬ５−１０．２×ΔＬ８＝０．０ ΔＳＤ＝−０．０２×ΔＳ１−０．１９×ΔＬ１＋７．０１×ΔＬ３ −２．０９×ΔＬ５＋０．１３×ΔＬ８＝０．０解がない場合には、歪曲誤差ΔＳＤ、倍率誤差ΔＢ、像
面湾曲ΔＹ、ピボタル傾きΔＰと片ボケΔＡＹそれぞれ
の量に最も近いものでよい。ΔSD = 0.77 × ΔS1 + 1.08 × ΔL1 + 4.40 × ΔL3−0.32 × ΔL5 + 0.58 × ΔL8 = 0.2 ΔB = −20.0 × ΔL1 + 20.0 × ΔL3 + 45.0 × ΔL5- 90.0 × ΔL8 = 0.3 ΔY = −0.10 × ΔS1−0.10 × ΔL1-22.7 × ΔL3 + 7.60 × ΔL5 + 38.1 × ΔL8 = 1.0 ΔP = 0.18 × ΔS1 + 0. 12 × ΔL1-1.71 × ΔL3 −0.50 × ΔL5-10.2 × ΔL8 = 0.0 ΔSD = −0.02 × ΔS1-0.19 × ΔL1 + 7.01 × ΔL3 -2.09 × ΔL5 + 0. 13 × ΔL8 = 0.0 If there is no solution, the distortion error ΔSD, the magnification error ΔB, the field curvature ΔY, the pivotal inclination ΔP and the one-sided blur ΔAY may be the closest ones.

【００７３】又、５つの量を補正するために、必ずしも
５つの未知数、即ち５つのレンズ間隔でなくともよく、
レンズ間の少なくとも１つ以上あるいは５つ以上であっ
てもよい。In order to correct the five amounts, it is not always necessary to use five unknowns, that is, five lens intervals.
It may be at least one or more or five or more between lenses.

【００７４】次に気圧や温度など周囲の環境や、露光エ
ネルギーの吸収によって時間的に変化する歪曲誤差、倍
率誤差、像面湾曲、ピボタル傾きと片ボケも、時間的変
化の各量を、測定あるいは予め計算することによって同
様にレンズ間の少なくとも１つ以上の間隔を調整して補
正することができる。Next, the amount of temporal change is measured for the ambient environment such as atmospheric pressure and temperature, and the distortion error, magnification error, field curvature, pivotal tilt and one-sided blur that change with time due to absorption of exposure energy. Alternatively, at least one or more intervals between the lenses can be similarly adjusted and corrected by calculating in advance.

【００７５】次に例えば対称歪曲誤差、投影倍率誤差の
２つを補正する場合について説明する。Next, a description will be given of a case where two errors, for example, a symmetric distortion error and a projection magnification error are corrected .

【００７６】このとき本実施例では環境変化に伴なう時
間的な対称歪曲誤差、投影倍率の変化に対してレチクル
とレンズを動かすことにより対称歪曲誤差、投影倍率を
調整している。At this time, in the present embodiment , a reticle is used to prevent a temporal symmetric distortion error and a change in projection magnification due to an environmental change.
By moving the lens, the symmetric distortion error and the projection magnification are adjusted.

【００７７】今、間隔Ｓ１の変化量をΔＳ１、間隔Ｌ１
の変化量をΔＬ１とすると表−２のデータより対称歪曲
と投影倍率の変化量ΔＳＤ，Δβは各々次式となる。Now, the change amount of the interval S1 is ΔS1, the interval L1
Let ΔL1 be the change amount of the symmetric distortion and the change amounts ΔSD and Δβ of the projection magnification from the data in Table 2.

【００７８】[0078]

【数２】従って対称歪曲と投影倍率の各々の修正目標値が与えら
れるとΔＬ１，ΔＳ１は次式で与えられる。(Equation 2) Therefore, when the correction target values of the symmetric distortion and the projection magnification are given, ΔL1 and ΔS1 are given by the following equations.

【００７９】[0079]

【数３】以上の値を利用して、本実施例では気圧、温度等の環境
の変化等による歪曲誤差の中で最も影響の多い投影倍率
誤差及び対称歪曲誤差の双方を良好に補正している。(Equation 3) By using the above values, in this embodiment, both the projection magnification error and the symmetric distortion error, which are the most influential among the distortion errors due to changes in the environment such as atmospheric pressure and temperature, are satisfactorily corrected.

【００８０】又、間隔Ｓ１、即ち投影光学系と物体面
（レチクル）の距離の変化による収差の変化は投影倍
率、ピント位置等の近軸量の変化に比べて通常少なく、
投影光学系内のレンズ間の空気間隔と比較しても収差量
の変化量と近軸量の変化量の比、即ち（収差量の変化量）／（近軸量の変化量）が小さい。これは投影光学系内での光線の傾きが物体面
と投影光学系の間の光線の傾きに比べて通常大きく、空
気間隔が変化した場合には屈折面での光線の入射高差が
大きくなるので収差変化が大きくなる為である。The change in the aberration due to the change in the distance S1, ie, the distance between the projection optical system and the object plane (reticle) is usually smaller than the change in the paraxial amount such as the projection magnification and the focus position.
The ratio of the amount of change in the amount of aberration to the amount of change in the paraxial amount, that is, (the amount of change in the amount of aberration) / (the amount of change in the amount of paraxial amount) is smaller than the air gap between the lenses in the projection optical system. This is because the inclination of the light beam in the projection optical system is usually larger than the inclination of the light beam between the object surface and the projection optical system, and when the air gap changes, the difference in the incident height of the light beam on the refraction surface increases. Therefore, the change in aberration becomes large.

【００８１】この為、本実施例では投影倍率の補正をレ
チクル３０を駆動手段６６で動かすことにより、主に間
隔Ｓ１で行ない、対称歪曲誤差に補正を投影光学系内の
レンズ５６を動かすことにより行なうようにし、これに
より投影倍率誤差と対称歪曲誤差を同時に良好に補正し
ている。特に対称歪曲以外の収差の変化が少ない空気間
隔を選ぶことにより、全ての光学性能を良好に維持して
いる。For this reason, in the present embodiment, the correction of the projection magnification is mainly performed at the interval S1 by moving the reticle 30 by the driving means 66, and the correction of the symmetrical distortion error is performed by moving the lens 56 in the projection optical system. Thus, the projection magnification error and the symmetric distortion error are simultaneously satisfactorily corrected. In particular, all optical performances are favorably maintained by selecting an air space having little change in aberrations other than symmetric distortion.

【００８２】投影光学系３１が両側テレセンの場合には
物体側をテレセントリックにする為にレンズが存在し、
これはフィールドレンズと呼ばれている。When the projection optical system 31 is telecentric on both sides, a lens exists to make the object side telecentric,
This is called a field lens.

【００８３】両側テレセンの場合にはレチクル〜レンズ
間を変化させても倍率及び対称歪曲以外の収差の変化は
僅少であるが、対称歪曲は変化する。又フィールドレン
ズを変化させると他の収差を悪化させずに倍率及び対称
歪曲を変化させることができる。そこで本実施例ではレ
チクル〜レンズ間及びフィールドレンズの２者を動かす
ことにより像性能は悪化させずに歪曲誤差を変化させて
いる。In the case of a double-sided telecentric lens, even if the distance between the reticle and the lens is changed, the change in aberration other than the magnification and the symmetric distortion is small, but the symmetric distortion changes. Further, when the field lens is changed, the magnification and the symmetric distortion can be changed without deteriorating other aberrations. Therefore, in the present embodiment, the distortion error is changed without deteriorating the image performance by moving the reticle to the lens and the field lens.

【００８４】本実施例では図８に示すようにレチクルＲ
の一部に設けたバーコード１００１をバーコードリーダ
ー（入力手段）１００２で読取り、レチクルに形成され
ているパターン形状や解像線等の情報を検出し、コント
ローラ５８に入力している。又、このパターン情報は操
作パネル等から成る入力手段５９によりコントローラ５
８に入力してもいい。コントローラ５８はバーコードリ
ーダーや入力手段５９からのパターン情報により、２次
光源の強度分布としてどのような分布が良いかを判断
し、それに基づいて駆動手段５０を駆動制御して例えば
図３（Ａ），（Ｂ）で示す強度分布となるように設定し
ている。In the present embodiment, as shown in FIG.
A bar code 1001 provided in a part of the reticle is read by a bar code reader (input means) 1002, and information such as a pattern shape and a resolution line formed on the reticle is detected and input to the controller 58. The pattern information is input to the controller 5 by input means 59 including an operation panel and the like.
8 may be entered. The controller 58 determines what distribution is good as the intensity distribution of the secondary light source based on the pattern information from the bar code reader or the input unit 59, and controls the driving of the driving unit 50 based on the determined distribution. ) And (B).

【００８５】[0085]

【発明の効果】本発明によれば投影露光するレチクル面
上のパターンの細かさ、方向性などを考慮して、該パタ
ーンに適合した照明系を選択することによって最適な高
解像力の投影露光を行なう際の投影光学系の光路の変更
に伴なう、即ち投影光学系の使用態様の違いから生じる
光学特性の違いを前述の如く調整することにより、常に
高い解像力を維持することができる半導体デバイスの製
造方法及びそれを用いた投影露光装置を達成することが
できる。According to the present invention, an optimal high-resolution projection exposure can be achieved by selecting an illumination system suitable for the pattern in consideration of the fineness and directionality of the pattern on the reticle surface to be projected and exposed. A semiconductor device that can always maintain a high resolving power by adjusting the difference in optical characteristics accompanying the change in the optical path of the projection optical system when performing, that is, the difference in the optical characteristics resulting from the difference in the usage of the projection optical system as described above. And a projection exposure apparatus using the same.

[Brief description of the drawings]

【図１】本発明の実施例１の要部概略図FIG. 1 is a schematic view of a main part of a first embodiment of the present invention.

【図２】投影光学系の瞳とオプティカルインテグレ
ータの関係を示す説明図FIG. 2 is an explanatory diagram showing a relationship between a pupil of a projection optical system and an optical integrator.

【図３】投影光学系の瞳面上を示す説明図FIG. 3 is an explanatory diagram showing a pupil plane of the projection optical system.

【図４】本発明で使用される絞りの詳細図FIG. 4 is a detailed view of an aperture used in the present invention.

【図５】超高圧水銀灯からケーブルの引き出し方を
示す図FIG. 5 is a diagram showing how to draw a cable from an ultra-high pressure mercury lamp.

【図６】本発明に係る投影光学系の瞳面上を示す説
明図FIG. 6 is an explanatory diagram showing a pupil plane of the projection optical system according to the present invention.

【図７】本発明に係る投影光学系の数値例のレンズ
断面図FIG. 7 is a lens sectional view of a numerical example of the projection optical system according to the present invention.

【図８】レチクル面上のバーコードの読取りを示す
説明図FIG. 8 is an explanatory diagram showing reading of a barcode on a reticle surface.

[Explanation of symbols]

１１超高圧水銀灯１２楕円ミラー１３ミラー１４シャッター１５レンズ１６波長選択フィルター１７オプティカルインテグレータ１８メカ絞り１９ミラー２０レンズ２１ハーフミラー２２マスキングブレード２３，２５ミラー２４，２６レンズ３０レチクル３１投影光学系３２ウエハ３３ウエハーチャック３４ウエハーステージ３５レーザー干渉計のミラー３６レーザー干渉計３７レチクルステージ３８レンズ３９ピンホール４０フォトディテクタ５０絞りの駆動系５１レンズ駆動系５２投光系５３受光系５４計算手段５５駆動手段５８コントローラ DESCRIPTION OF SYMBOLS 11 Ultra-high pressure mercury lamp 12 Elliptical mirror 13 Mirror 14 Shutter 15 Lens 16 Wavelength selection filter 17 Optical integrator 18 Mechanical stop 19 Mirror 20 Lens 21 Half mirror 22 Masking blade 23, 25 Mirror 24, 26 Lens 30 Reticle 31 Projection optical system 32 Wafer 33 Wafer chuck 34 Wafer stage 35 Laser interferometer mirror 36 Laser interferometer 37 Reticle stage 38 Lens 39 Pinhole 40 Photodetector 50 Aperture drive system 51 Lens drive system 52 Light projection system 53 Light reception system 54 Calculation means 55 Drive means 58 Controller

フロントページの続き (58)調査した分野(Int.Cl.⁷，ＤＢ名) H01L 21/027 G03F 7/20 Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/027 G03F 7/20

Claims

(57) [Claims]

1. A secondary light source is formed by light from a light source.
Illuminating a circuit pattern with a light beam from a next light source, and exposing the substrate with the circuit pattern by projecting the illuminated circuit pattern onto the substrate by a projection optical system, the method of manufacturing a semiconductor device, Independently of the adjustment for correcting the change in the optical characteristics of the projection optical system due to the exposure, the projection magnification, the symmetric distortion, the field curvature, and the one-sided projection of the projection optical system are changed according to the change in the shape of the secondary light source.
A method for manufacturing a semiconductor device, comprising adjusting at least one of a tilt and a pivotal inclination .

2. A secondary light source is formed by light from a light source.
Illuminating the circuit pattern by the light beam from the next source, method of manufacturing a semiconductor device including the step of projecting on the substrate by the illuminated circuit pattern projection optical system, wherein
Projection magnification of projection optical system, symmetric distortion, field curvature, one-sided
The second order of at least one of ke and pivotal inclination
A method for manufacturing a semiconductor device, wherein a change due to a change in the shape of a light source is corrected .

3. A secondary light source is formed by light from the light source.
Illuminating a circuit pattern with a light beam from a secondary light source, and projecting the illuminated circuit pattern onto a substrate by a projection optical system, the method comprising: changing the shape of the secondary light source; Projection optics
Projection magnification, symmetric distortion, field curvature, one-sided blur and pivot
A method for manufacturing a semiconductor device, wherein at least one of the tilts is adjusted.

4. The method according to claim 1, wherein a shape of said secondary light source is changed according to a type of said circuit pattern.
Or 3) the method of manufacturing a semiconductor device.

5. The circuit pattern according to claim 1, wherein the minimum line width is relatively large.
The minimum line width between the first original plate and the circuit pattern is relatively small
When the second original plate is used and the first original plate is used,
A secondary light source having a light source section near the optical axis is formed, and the second light source is formed.
When using a plate, a secondary light source whose light source is off the optical axis
5. The method according to claim 4, wherein the semiconductor device is formed .

6. A secondary light source formed off the optical axis.
A circular ring-shaped light source or a substantially rectangular ring-shaped light
When orthogonal coordinates are determined from the source unit or the optical axis as the origin, the orthogonal
6. The method according to claim 5, wherein each of the four quadrants of coordinates has an independent light source unit .

7. A secondary light source is formed by light from a light source.
Illuminating the circuit pattern with a light beam from the next light source;
The projected circuit pattern onto the substrate by the projection optical system.
Exposing the substrate with the circuit pattern
A method of manufacturing a semiconductor device, comprising:
A key for correcting a change in optical characteristics of the projection optical system due to light.
Independent of the adjustment, according to a change in the shape of the secondary light source,
Adjusting at least one optical characteristic of a projection optical system
The minimum line width of the circuit pattern is relatively large
The second line in which the minimum line width between the first original plate and the circuit pattern is relatively small
When an original plate is used, when the first original plate is used,
A secondary light source having a light source section near the optical axis is formed, and the second light source is formed.
When using a plate, define the rectangular coordinates with the optical axis as the origin.
When the light source is turned on, the light source unit
A method of manufacturing a semiconductor device, wherein an standing secondary light source is used .

8. A secondary light source is formed by light from the light source.
Illuminating the circuit pattern with a light beam from the next light source;
The projected circuit pattern onto the substrate by the projection optical system.
The method of manufacturing a semiconductor device, comprising:
The secondary light source having at least one optical characteristic of a projection optical system;
To correct the change due to the change of the shape of
Circuit board with a relatively large minimum line width
A second blank with a relatively small minimum line width is used.
When the first original plate is used, the light source section is located near the optical axis.
When the secondary light source is used and the second original plate is used
When the orthogonal coordinates are determined with the optical axis as the origin,
Quadratic that exists independently in each of the four quadrants of the Cartesian coordinates
A method for manufacturing a semiconductor device, wherein a light source is used .

9. A secondary light source is formed by light from a light source.
Illuminating the circuit pattern with a light beam from the next light source;
The projected circuit pattern onto the substrate by the projection optical system.
The method of manufacturing a semiconductor device, comprising:
Of the projection optical system, which is changed by changing the shape of the secondary light source.
Adjusting at least one optical property, wherein
The first original plate having a relatively large minimum line width of the circuit pattern and the circuit
Used with the 2nd original plate where the minimum line width of the road pattern is relatively small
When it is, the optical axis is the light source unit to when using the first master plate
A secondary light source in the vicinity is formed, and the second original plate is used.
In the case, when the orthogonal coordinates are defined with the optical axis as the origin, the light source
Part exists independently in each of the four quadrants of the Cartesian coordinates
A method for manufacturing a semiconductor device, wherein a secondary light source is used .

10. The x and y directions of the rectangular coordinates and the circuit.
Each direction of the vertical and horizontal pattern that mainly forms the pattern
The method for manufacturing a semiconductor device according to any one of claims 6 to 9, wherein the values substantially coincide with each other .

11. A projection magnification and a symmetric distortion of the projection optical system.
The circuit pattern and the projection optics for adjusting aberrations
11. The system according to claim 1, wherein the distance between the systems is adjusted.
Any one of the semiconductor device manufacturing methods.

12. A projection magnification and a symmetric distortion of the projection optical system.
The refractive power of the projection optical system is adjusted to adjust the aberration
The method for manufacturing a semiconductor device according to claim 1, wherein:

13. A secondary light source is formed by light from a light source.
Illumination that illuminates the pattern on the original plate with the light flux from the secondary light source
Bright optics and projecting the illuminated pattern onto a substrate
A projection exposure apparatus having a projection optical system;
Adjustment to correct the change in the optical characteristics of the projection optical system due to
Independently project the projection according to a change in the shape of the secondary light source.
Projection magnification of optical system, symmetric distortion, field curvature, one-sided blur
Means for adjusting at least one of tilt and pivotal tilt
A projection exposure apparatus comprising:

14. A secondary light source is formed by light from a light source.
Illumination that illuminates the pattern on the original plate with the light flux from the secondary light source
Bright optics and projecting the illuminated pattern onto a substrate
A projection exposure apparatus having a projection optical system;
Projection magnification of optical system, symmetric distortion, field curvature, one-sided blur
And at least one of the following:
Having a means for correcting the change due to the change of the shape of
Characteristic projection exposure apparatus.

15. A secondary light source is formed by light from a light source.
Illumination that illuminates the pattern on the original plate with the light flux from the secondary light source
Bright optics and projecting the illuminated pattern onto a substrate
A projection exposure apparatus having a projection optical system;
Projection of the projection optical system changed by changing the shape of the light source
Magnification, symmetric distortion, field curvature, unilateral blur and pivotal tilt
Having means for adjusting at least one of
A projection exposure apparatus.

16. The shape of said secondary light source is determined by the type of said original plate.
Claims 13 and 14 characterized by the following:
Are 15 projection exposure apparatuses.

17. The minimum line width of the pattern as the original plate
Relatively small first original plate and pattern have relatively small minimum line width
When the second original plate is used and the first original plate is used
Is formed with a secondary light source having a light source unit near the optical axis.
If two original plates are used, the secondary light whose light source is off the optical axis
17. The projection exposure of claim 16, wherein a source is formed.
apparatus.

18. A secondary light source formed off the optical axis,
An almost circular ring-shaped light source or an almost rectangular ring
When orthogonal coordinates are determined from the light source or the optical axis as the origin,
Each quadrant of the intersection must have an independent light source section
18. The projection exposure apparatus according to claim 17, wherein:

19. An illumination optical system for forming a secondary light source with light from a light source and illuminating a pattern on an original plate with a light beam from the secondary light source, and a projection optical system for projecting the illuminated pattern onto a substrate. A projection exposure apparatus having at least one optical characteristic of the projection optical system according to a change in the shape of the secondary light source, independently of adjustment for correcting a change in the optical characteristic of the projection optical system due to projection exposure. have the means to adjust the
And a first original plate having a relatively large minimum line width of the pattern.
A second original plate having a relatively small minimum line width of the pattern is used.
When using the first original plate, the light source section
A secondary light source near the axis is formed, and the second original plate is used.
When the orthogonal coordinates are defined with the optical axis as the origin,
Sources are independently located in each of the four quadrants of the Cartesian coordinates
And a secondary light source .

20. An illumination optical system for forming a secondary light source with light from a light source, and illuminating a pattern on an original plate with a light beam from the secondary light source, and a projection optical system for projecting the illuminated pattern onto a substrate. And a means for correcting a change in at least one optical characteristic of the projection optical system due to a change in the shape of the secondary light source.
Between the first original plate having a relatively large minimum line width and the pattern
When a second original plate having a relatively small minimum line width is used,
When the first original plate is used, the light source section is located near the optical axis.
When the next light source is formed and the second original plate is used,
When orthogonal coordinates are defined with the optical axis as the origin, the light source
Secondary light sources that exist independently in each of the four quadrants of coordinates are used.
A projection exposure apparatus characterized by being used.

21. An illumination optical system for forming a secondary light source with light from a light source, and illuminating a pattern on an original plate with a light beam from the secondary light source, and a projection optical system for projecting the illuminated pattern onto a substrate. A projection exposure apparatus comprising: means for adjusting at least one optical characteristic of the projection optical system according to a change in the shape of the secondary light source ;
The first original plate having a relatively large minimum line width and the minimum of the pattern
When a second original having a relatively small line width is used, the first original
When an original plate is used, the light source section is a secondary light near the optical axis.
If a source is formed and the second master is used, the light source
When the rectangular coordinates are determined with the axis as the origin, the light source unit
Secondary light sources that exist independently in each of the four quadrants
A projection exposure apparatus which is characterized in that.

22. The x and y directions of said rectangular coordinates and said original plate
Each direction of the vertical and horizontal pattern that mainly forms the pattern
Are substantially equal to each other.
Some projection exposure equipment.

23. A projection magnification and a symmetric distortion of the projection optical system.
The distance between the original plate and the projection optical system to adjust aberration
23 is adjusted.
Re one of the projection exposure apparatus.

24. A projection magnification and a symmetric distortion of the projection optical system.
The refractive power of the projection optical system is adjusted to adjust the aberration.
The projection exposure apparatus according to any one of claims 13 to 22, wherein the projection exposure apparatus is used.

25. The projection exposure apparatus according to claim 13, wherein an illuminance distribution is adjusted according to a change in the shape of said secondary light source.

26. The minimum size of a pattern formed on the original plate.
Enter information about the line width into the controller of the device.
Means, the controller according to the information,
The shape of the secondary light source of the illumination optical system is adjusted.
A projection exposure apparatus according to any one of claims 13 to 22 .

27. The input means is formed on the original plate.
Means for reading a barcode on which the information is recorded or
The apparatus according to claim 1, further comprising an operation panel of the apparatus.
26 projection exposure apparatus.