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本発明は、例えば半導体素子又は液晶表示素子等をフォトリソグラフィ工程で製造する際に使用されるステッパー等の投影露光装置の投影光学系に関する。 The present invention relates to a projection optical system of a projection exposure apparatus such as a stepper which is used in fabricating semiconductor devices or liquid crystal display element or the like in the photolithography process. 特に、本発明は、光学系の要素として反射系を用いた反射屈折投影光学系に関する。 In particular, the present invention relates to a catadioptric projection optical system using a reflection system as an element of the optical system.
半導体素子又は液晶表示素子等をフォトリソグラフィ工程で製造する際に、レチクル(又はフォトマスク等)のパターン像を投影光学系を介して例えば1/4〜1/5程度に縮小して、フォトレジスト等が塗布されたウェハ(又はガラスプレート等)上に露光する投影露光装置が使用されている。 A semiconductor element or a liquid crystal display element or the like in manufacturing a photolithography process, by reducing the pattern image of the reticle (or photomask, etc.), for example, about 1 / 4-1 / 5 through a projection optical system, the photoresist projection exposure apparatus has been used for like is exposed onto the wafer coated (or a glass plate or the like). 投影露光装置としては、従来は主にステッパーのような一括露光方式が使用されていた。 The projection exposure apparatus, conventionally shot exposure method as mainly stepper has been used.
近年、半導体の製造や半導体チップ実装基板の製造ではますます微細化しており、これらのパターンを焼き付ける露光装置は、より解像力の高いものが要求されている。 In recent years, more and more miniaturization in the manufacture of semiconductor manufacturing and semiconductor chip mounting substrate, the exposure apparatus to burn these patterns are more having a high resolution is required.
この要求を満足するためには、露光用の光源の波長(露光波長)を短波長化するか、又は投影光学系の開口数NAを大きくしなければならない。 To satisfy this requirement, or a shorter wavelength of the wavelength (exposure wavelength) of the light source for exposure, or shall increase the numerical aperture NA of the projection optical system. しかしながら、露光波長が短くなると照明光の吸収のため実用に耐える光学ガラスが限られており、屈折系のみで投影光学系を構成することは困難である。 However, the exposure wavelength becomes and the optical glass is limited for practical use because of the absorption of the illumination light shorter, it is difficult to constitute a projection optical system only with refraction system. 特に、波長が300nm以下となると、実用上使用できる硝材は、合成石英と螢石とのみになってしまう。 In particular, when the wavelength is 300nm or less, practical glass material that can be used, it becomes only the synthetic quartz and fluorite.
一方、反射系のみで投影光学系を構成することも試みられているが、この場合、投影光学系が大型化し、且つ反射面の非球面化が必要となる。 On the other hand, attempts have been made to the projection optical system only in a reflection system, in this case, the projection optical system becomes large, and aspheric reflective surface is required. ところが、大型の高精度の非球面を製作するのは極めて困難である。 However, it is extremely difficult to fabricate the aspheric surface of a large high accuracy.
そこで、反射系と使用される露光波長に耐える光学ガラスからなる屈折系とを組み合わせたいわゆる反射屈折光学系で投影光学系を構成する技術が種々提案されている。 A technique for constructing the projection optical system by a so-called catadioptric system that combines a dioptric system formed of the optical glass to withstand exposure wavelength used and the reflection systems have been proposed.
その一例として、凹面鏡を1枚含む光学系と屈折光学系とを組み合わせて所定の縮小倍率のもとでレチクルの像を投影する反射屈折光学系が、例えば米国特許第4,779,966号公報、特開平4−234722号公報に開示されている。 As an example, catadioptric optical system for projecting a reticle image under a predetermined reduction magnification by combining optical system comprising one concave mirror and a refraction optical system, for example, U.S. Patent No. 4,779,966 Publication It is disclosed in Japanese Patent Laid-Open No. 4-234722.
上記米国特許第4,779,966号公報に開示される反射屈折光学系は、物体側から順に、屈折光学系と、この屈折光学系による中間像を再結像させる反射屈折光学系とから構成されている。 The U.S. catadioptric optical system disclosed in Japanese Patent No. 4,779,966 publication, consists in order from the object side, a dioptric system, a catadioptric optical system for re-imaging the intermediate image by the refractive optical system It is.
また、特開平4−234722号公報に開示される光学系は、物体側から順に、完全対称型の反射屈折光学系と、この反射屈折光学系による中間像を縮小倍率のもとで再結像させる屈折光学系とから構成されている。 The optical system disclosed in Japanese Patent Laid-Open No. 4-234722, in order from the object side, a completely symmetric catadioptric optical system, re-imaging the intermediate image by the catadioptric optical system under demagnification and a refractive optical system to.
上記米国特許第4,779,966号公報及び特開平4−234722号公報に開示される反射屈折光学系では、凹面鏡を含む反射屈折光学系中の屈折光学部材として、負屈折力のレンズ成分のみを用いていた。 In the U.S. Patent No. 4,779,966 and JP Laid catadioptric system No. disclosed in Japanese 4-234722, as a refractive optical element in the catadioptric optical system including a concave mirror, only the lens component having a negative refractive power the has been used. 従って、物体(中間像)から凹面鏡へ達する光束の光束径は拡大される一方であるため、凹面鏡自体の口径の小型化を図ることが困難であった。 Accordingly, since the beam diameter of the light beam which reaches the object (intermediate image) to the concave mirror which is one to be expanded, it is difficult to reduce the size of the diameter of the concave mirror itself.
上述の問題点に加えて、特に上記米国特許第4,779,966号公報に開示される反射屈折光学系において、像側の開口数を上げることを考えると、像側に近い光学系の開口数を上げざるを得ない。 In addition to the problems described above, particularly in the United States catadioptric optical system disclosed in Japanese Patent No. 4,779,966 Publication Given that increasing the numerical aperture on the image side, the aperture of the optical system closer to the image side inevitably raise the number. このときには、像側に配置される反射屈折光学系中の凹面鏡に入射させる光束の径を拡大させる必要があるため、この凹面鏡の口径が大型化する問題点がある。 At this time, it is necessary to enlarge the diameter of the light beam to be incident on the concave mirror in the catadioptric optical system disposed on the image side, there is a problem in that the diameter of the concave mirror becomes large. さらに、米国特許第4,779,966号公報に開示される反射屈折光学系では、縮小倍率の関係から凹面反射鏡M 2からウェハに到る光路が長く取れないため、この光路中に配置される屈折レンズのレンズ枚数を多くすることができず、十分な結像性能が得られにくいという不都合があった。 Further, in the catadioptric optical system disclosed in U.S. Pat. No. 4,779,966, the optical path reaching the wafer from the concave reflecting mirror M 2 from the relationship of reduction ratio can not be taken long, arranged in the optical path It can not be much the number of lenses of the refractive lens that sufficient imaging performance is a disadvantage that is difficult to obtain. また、このため、最もウェハ側の光学素子の端面とウェハとの距離、即ちウェハ側の作動距離(ワーキングディスタンス)が長く取れないという不都合があった。 Further, Therefore, there is a disadvantage that most distance between the end surface and the wafer of the wafer side optical element, i.e. the wafer-side working distance (working distance) can not be taken long.
また、特開平4−234722号公報に開示された反射屈折光学系では、往路と復路とが兼用となる光学系が完全対称型の光学系を構成しており、そこの光学系での収差発生を極力抑え、後に続く屈折光学系の収差補正負担を軽くしているものであるが、対称型光学系を構成しているため、第1面付近での作動距離(ワーキングディスタンス)が長く取れないという不都合があった。 Further, in the catadioptric optical system disclosed in JP-A-4-234722, an optical system forward path and the backward path and is also used have to form a complete symmetric optical system, aberration occurs in the bottom of the optical system minimized and it is intended that reduce the aberration correction burden subsequent refractive optics later for constituting the symmetric optical system, the working distance near the first surface (working distance) can not be taken long there is a disadvantage that.
以上のことに鑑み、本発明は、光学系の性能を劣化させることなく、凹面鏡の口径の小径化を達成することを目的とする。 In view of the above, the present invention is, without degrading the performance of the optical system, which aims to achieve a diameter of the aperture of the concave mirror. 更に、本発明は、凹面鏡の口径の小径化を達成しつつ、作動距離を十分に確保し、高い開口数を実現することを第2の目的とする。 Furthermore, the present invention, while achieving the diameter of the aperture of the concave mirror, a working distance sufficiently secured, and the second object to realize a high numerical aperture.
前記第1 反射屈折結像光学系と前記第2 屈折結像光学系との合成倍率は縮小倍率である反射屈折光学系を提供する。 Resultant magnification of said second refractive imaging optical system and the first catadioptric imaging optical system provides a catadioptric optical system is a reduction magnification.
上述の構成の如き本発明によれば、凹面鏡の前側に配置される第3レンズ群G3が正の屈折力を有しているため、第1面から発した光束に収束作用を及ぼし、第4レンズ群G4に入射する光束が絞り込まれる。 According to the present invention as configured as described above, since the third lens group is disposed in front of the concave mirror G3 has a positive refractive power, exerts a converging effect on the light beam emitted from the first surface, the fourth the light beam incident on the lens group G4 is narrowed. これにより、第4レンズ群G4中の凹面鏡は、小型化が達成される。 Accordingly, the concave mirror in the fourth lens group G4, downsizing is achieved. また、第3レンズ群G3を正の屈折力の第10レンズ群G10、負の屈折力の第11レンズ群G11、正の屈折力の第12レンズ群G12と構成することにより、諸収差を良好に補正することができる。 Further, by configuring the third lens group G3 tenth lens group G10 of positive refractive power, a 11 lens group G11 having negative refractive power, a second lens group G12 having positive refractive power, aberrations good it can be corrected to. 更に、この上述の構成により、第1結像光学系の長さを短くすることも可能である。 In addition, this configuration described above, it is possible to shorten the length of the first imaging optical system.
また、本発明では、上述の構成により、第1面付近の作動距離を大きくすることができるため、光路偏向部材が容易に挿入可能となる。 In the present invention, the construction described above, it is possible to increase the working distance near the first surface, the optical path deflecting member is easily inserted. ここで、光路偏向部材は単に光路を折り曲げる機能のみを持つようにすることが、好ましい。 Here, the optical path deflecting member is simply to have only a function of bending the optical path is preferred. このような光路偏向部材とすれば、ビームスプリッタの如く光束を分離する光路偏向部材の機能を持たせる必要がないため、光量損失をほぼ0%に抑えることが可能となり、フレアーの発生も極めて少なくできる利点が生じる。 With such an optical path deflecting member, it is not necessary to provide a function of optical path deflecting member for separating the light beam as the beam splitter, it is possible to suppress the amount of light loss almost 0%, extremely low generation of flare the advantage that can arise. 単に光路を折り曲げる機能のみを持つ光路偏向部材では、ビームスプリッタを用いる場合において発生するビームスプリッタの光分割面の特性の不均一性による収差の発生や、熱吸収により光分割面の特性が変化することによる収差の発生は、生じない。 Simply optical path deflecting member having only a function of bending the optical path, aberration or due to non-uniformity of characteristics of the light splitting surface of the beam splitter that occurs in the case of using the beam splitter, the characteristics of the light splitting surface by heat absorption changes the occurrence of aberration does not occur due to the fact.
ここでは、光路偏向部材を第1結像光学系が形成する中間像の近傍に配置することがさらに好ましい。 Here, it is more preferable to arrange the optical path deflecting member in the vicinity of the intermediate image by the first imaging optical system is formed. この構成により、光路を折り曲げる際の偏心誤差の影響を非常に少なくできる。 This arrangement enables very low influence of eccentricity errors in bending the optical path. 例えば、光路偏向部材に角度誤差が生じている場合には、第1結像光学系に対する第2結像光学系の偏心を招くことになるが、この結果としては、第2面上に形成される像が第1面に対してシフトするだけになり、結像性能に対する影響はほとんど生じない。 For example, if the angle error in the optical path deflecting member has occurred, but leads to an eccentricity of the second imaging optical system with respect to the first imaging optical system, as a result, formed on the second surface that the image is only shifted relative to the first surface, the impact on the imaging performance hardly occurs.
本発明では、第2結像光学系中に凹面鏡を持たない構成であるため、高い開口数のもとでも、像側の作動距離を十分に確保することができる。 In the present invention, since in the second imaging optical system is a structure that does not have a concave mirror, even under high numerical aperture, it is possible to sufficiently secure the working distance on the image side.
また、本発明においては、第2結像光学系は、正屈折力の第5レンズ群G5と、正屈折力の第6レンズ群G6とを有する構成が好ましい。 In the present invention, the second imaging optical system, a fifth lens group G5 having a positive refractive power, a configuration and a sixth lens unit G6 having a positive refractive power are preferred. そして、本発明においては、これらの第5レンズ群G5と第6レンズ群G6との間の光路中に開口絞りを配置する構成をとることが好ましい。 Then, in the present invention, it is preferable to adopt a configuration in which the aperture stop is disposed in an optical path between these fifth lens group G5 and the sixth lens group G6. この開口絞りを可変開口絞りとすれば、コヒーレンスファクタ(σ値)を調整できる。 If the aperture stop and a variable aperture stop can be adjusted coherence factor (sigma value).
ここで、焦点深度を深くして且つ解像力を上げる一つの手法として、例えば特公昭62−50811号公報において、レチクルのパターン中の所定部分の位相を他の部分からずらす位相シフト法が提案されている。 Here, as one of the techniques for increasing the and resolution and depth of focus, for example, in Japanese Patent Publication 62-50811 and JP been proposed phase shift method for shifting the phase of a predetermined portion in the pattern of the reticle from other parts there. 本発明においては、コヒーレンスファクタ(σ値)を調整することが可能であるため、この位相シフト法の効果をさらに向上できる利点がある。 In the present invention, since it is possible to adjust the coherence factor (sigma value), there is an advantage that the effect of this phase shift method can be further improved.
本発明では、前記第1結像光学系は縮小倍率を有し、前記第2結像光学系は縮小倍率を有することが好ましい。 In the present invention, the first imaging optical system has a reduction magnification, the second imaging optical system preferably has a reduction magnification. この様な屈折力の配置によって、光学系を無理なく構成することができる。 The arrangement of such a power can be configured without difficulty optics.
また、本発明においては、第1結像光学系は、第1面と第3レンズ群G3との間の光路中に配置された第7レンズ群G7を有するように構成されることが好ましい。 In the present invention, the first imaging optical system is preferably configured to have a seventh lens group G7 which are disposed in an optical path between the first surface and the third lens group G3. この第7レンズ群G7は、第1結像光学系及び第2結像光学系では補正しきれない非対称収差、特に歪曲収差、倍率色収差を良好に補正する機能を有する。 The seventh lens group G7 has asymmetrical aberrations in the first imaging optical system and the second imaging optical system can not be corrected, especially distortion, the ability to satisfactorily correct lateral chromatic aberration. そして、この第7レンズ群G7は、第1面側から順に、正屈折力の前群と、負屈折力の後群とを有するように構成されることが好ましい。 Then, the seventh lens group G7, in order from the first surface side, a front group having positive refractive power, is preferably configured to have a rear group having negative refractive power. この構成により、第7レンズ群G7全体としては小径化を達成しつつ、テレセントリック性を良好に維持できる。 With this configuration, as a whole seventh lens group G7 while achieving small diameter, it can be preferably maintained telecentricity.
本発明において、第2結像光学系を構成する光学材料は、互いに分散値の異なる少なくとも二種類の光学材料であることが好ましい。 In the present invention, an optical material constituting the second imaging optical system is preferably at least two kinds of optical materials having different different dispersion values. これにより、色収差の補正効果を向上できる。 Thus, it is possible to improve the effect of correcting chromatic aberration.
また、本発明において、第2結像光学系中の前記第5レンズ群G5は、高分散ガラスから構成される負レンズ成分と、低分散ガラスから構成される正レンズ成分とを含むように構成され、第2結像光学系中の前記第6レンズ群G6は、低分散ガラスから構成される正レンズ成分を含むように構成されることが好ましい。 In the present invention, the in the second imaging optical system the fifth lens group G5 is configured to include a negative lens component composed of a high dispersion glass and a positive lens component made of a low dispersion glass it is, the sixth lens group G6 in the second imaging optical system is preferably configured to include a positive lens component composed of a low dispersion glass. この構成により、色収差の補正効果をさらに向上できる利点がある。 This configuration has the advantage of further improving the correction effect of chromatic aberration.
更に、本発明では、以下の条件を満足することが好ましい。 Further, in the present invention, it is preferable to satisfy the following condition.
ここで、Y0は第1面上の物体の高さであり、Y1は前記第1結像光学系によって結像される前記中間像の高さである。 Here, Y0 is the height of the object on the first surface, Y1 is the height of the intermediate image formed by said first imaging optical system.
以上の様な条件範囲とすることにより、無理なく光学系を構成することが可能となる。 With more such conditions ranges, it is possible to configure reasonably optics. 下限を超えると、第1結像光学系の縮小倍率が大きくなり、広範囲の露光が困難になる。 Below the lower limit, the reduction magnification of the first imaging optical system is increased, a wide range of exposure becomes difficult. また、上限を超えると、第1群の縮小倍率が小さくなり、凹面鏡を小型化するという本発明の目的から外れることになる。 If it exceeds the upper limit, the reduction ratio of the first group becomes small, so that out of the concave mirror from the object of the present invention that compact. 尚、下限を0.6、上限を1.0とすると、更に良い結果が得られる。 Incidentally, the lower limit 0.6 and the upper limit to 1.0, even better results are obtained.
また更に、本発明では、以下の条件を満足することが好ましい。 Furthermore, in the present invention, it is preferable to satisfy the following condition.
ここで、βは、全体の倍率である。 Here, beta is the overall magnification.
以上の様な条件範囲とすることにより、前記条件(1)同様に、無理なく光学系を構成することが可能となる。 With more such condition range, the condition (1) Similarly, it is possible to configure reasonably optics. 下限を超えると、縮小倍率が大きくなり、広範囲の露光が困難になる。 Below the lower limit, the reduction ratio is increased, a wide range of exposure becomes difficult. また、上限を超えると、光学系の縮小倍率が小さくなり、縮小投影露光装置とは言えなくなってしまう。 If it exceeds the upper limit, the reduction magnification of the optical system is reduced, no longer be said to be a reduction projection exposure apparatus. ここで、下限を1/8とすると、更に良い結果が得られる。 Here, the lower limit is 1/8, even better results are obtained.
また、本発明は、以下の条件を満たすことが望ましい。 Further, the present invention preferably satisfies the following conditions.
ここで、P4は、第4レンズ群G4のペッツバール和である。 Here, P4 is a Petzval sum of the fourth lens group G4. もし、条件(3)を満足しないと、第4レンズ群G4に入射する光束に対し射出する光束が大きくなるため、第3レンズ群G3の各レンズが大型化するようになるので、好ましくない。 If the do not satisfy the condition (3), since the light flux emitted to the light beam incident on the fourth lens group G4 is increased, since the lenses of the third lens group G3 becomes larger, undesirable. また更に、反射屈折光学系自体のペッツバール和が大きくなり、像面が平坦でなくなるので、好ましくない。 Furthermore, the Petzval sum of the catadioptric optical system itself becomes large, since the image surface is not flat, which is not preferable.
更に、本発明は、以下の条件を満たすことが望ましい。 Furthermore, the present invention preferably satisfies the following conditions.
ここで、P3は第3レンズ群G3のペッツバール和であり、P5は第5レンズ群G5のペッツバール和であり、P6は第6レンズ群G6のペッツバール和であり、P7は第7レンズ群G7のペッツバール和である。 Here, P3 is the Petzval sum of the third lens group G3, P5 is a Petzval sum of the fifth lens group G5, P6 is a Petzval sum of the sixth lens group G6, P7 is the G7 seventh lens group is a Petzval sum. もし、条件(4)を満足しないと、反射屈折光学系全体の倍率が大きくなり、好適な縮小倍率が得られなくなるので、好ましくない。 If the do not satisfy the condition (4), the catadioptric optical system as a whole magnification becomes large, so a suitable reduction ratio can not be obtained, which is not preferable.
また更に、本発明は、以下の条件を満たすことが望ましい。 Furthermore, the present invention preferably satisfies the following conditions.
上記条件は、光学系の全構成要素のペッツバール和に関するものである。 The above condition relates to Petzval's sum of all components of the optical system. もし、条件(5)を満足しないと、像面がプラス側に湾曲するようになり、像面での平坦性がなくなるので、好ましくない。 If the do not satisfy the condition (5), now the image surface is curved to the plus side, since there is no flatness of the image plane, which is not preferable.
そして、本発明は、以下の条件を満たすことが望ましい。 The present invention preferably satisfies the following conditions.
と表すことができる。 It can be expressed as. もし、条件(6)を満足しないと、像面の平坦性がなくなるので、好ましくない。 If the do not satisfy the condition (6), since the flatness of the image plane is eliminated, undesirable.
以下、本発明による反射屈折光学系の実施例を図面を参照して説明する。 Hereinafter, an embodiment of a catadioptric optical system according to the present invention with reference to the drawings. 以下に説明する各実施例は、レチクル上に形成されたパターンの像をレジストが塗布されたウェハ上に転写する露光装置の投影光学系に本発明を適用したものである。 Each embodiment described below is one in which an image of a pattern formed on reticle resist the present invention is applied to a projection optical system of an exposure apparatus for transferring onto a wafer coated.
まず、図1を参照して、本発明による反射屈折光学系の概略的な構成を説明する。 First, referring to FIG. 1, illustrating a schematic configuration of a catadioptric optical system according to the present invention. 図1において、光軸からの高さがY0で第1面上のレチクルRからの光束は、正の屈折力を有する第10レンズ群G10と負の屈折力を有する第11レンズ群G11と正の屈折力を有する第12レンズ群G12とを含む第3レンズ群G3を通過した後に、凹面鏡M1と前記第1面側に凹面を向けたメニスカス成分とを有する第4レンズ群G4に達する。 In Figure 1, the light flux from the reticle R of the height from the optical axis on the first surface at Y0 includes a first lens group G11 having a tenth lens group G10 and a negative refractive power having a positive refractive power positive of after passing through the third lens group G3 includes a twelfth lens group G12 having a refractive power, reaches the fourth lens group G4 having a meniscus component having a concave surface facing the concave mirror M1 the first surface side. 第2実施例中では上述の第3レンズ群G3と第4レンズ群G4とで第1結像光学系G1を構成しているが、第1実施例中では、第1面上のレチクルRと第3レンズ群G3との間に、正の屈折力を有する第8レンズ群G8と負の屈折力を有する第9レンズ群G9とから構成される第7レンズ群G7が存在する。 The in the second embodiment constitutes a first imaging optical system G1 in the third lens group G3 described above and the fourth lens group G4, but in the first embodiment, the reticle R on the first surface between the third lens group G3, a positive seventh lens group G7 consists ninth lens G9 and having an eighth lens G8 and a negative refractive power having a refractive power is present.
ここで、第3レンズ群G3を通過した光束は、第4レンズ群G4に達する。 Here, the light beam which has passed through the third lens group G3 reaches the fourth lens group G4. この第4レンズ群G4に達した光束は、第4レンズ群G4中の凹面鏡M 1によって反射され、再び第3レンズ群G3を通過して、光路偏向部材としての光路折曲げミラーM 2へ向かう。 The light beam reaching the fourth lens group G4 is reflected by the concave mirror M 1 in the fourth lens group G4, directed through the third lens group G3 again, the optical path bending mirror M 2 as a light path deflecting member . この光路折曲げミラーM 2は、第1結像光学系G1、第2結像光学系G2の光軸に対して45°で斜設されている。 The optical path bending mirror M 2, the first imaging optical system G1, which is obliquely disposed at 45 ° with respect to the optical axis of the second imaging optical system G2. そして、第1結像光学系G1からの光束は、収斂光束となり、光路折曲げミラーM 2の近傍にレチクルRの中間像をY1の高さで形成する。 Then, the light flux from the first imaging optical system G1 becomes a converging light flux, in the vicinity of the optical path bending mirror M 2 an intermediate image of the reticle R is formed at a height of Y1. 次に、光路折曲げミラーM 2にて反射された光束は、第2結像光学系G2を構成する第5レンズ群G5及び第6レンズ群G6を順に介して、第2面上のウェハーW上にレチクルRの2次像(中間像の像)を形成する。 Then, the light beam reflected by the optical path bending mirror M 2 is the fifth lens group G5 and the sixth lens group G6 constituting the second imaging optical system G2 through sequentially, wafer W on the second surface to form a secondary image of the reticle R (the image of the intermediate image) above. ここで、第5レンズ群G5と第6レンズ群G6との間には、開口絞りaが配置されている。 Here, the fifth lens group G5 is formed between the sixth lens group G6, the aperture stop a is disposed.
また、図2は、本発明による反射屈折光学系の別の配置を示す図である。 2 is a diagram showing another arrangement of the catadioptric optical system according to the present invention. 尚、図2においては、図1と同様の機能を有する部材には同一の符号を付してある。 In FIG. 2, members having the same functions as those in FIG. 1 are denoted by the same reference numerals.
図2において、図1の例とは異なる点は、第1面と第3レンズ群G3との間の光路中に、光路偏向部材としての光路折曲げミラーM 0を配置した点である。 2, differs from the example of Figure 1, in the optical path between the first surface and the third lens group G3, it is the point where the optical path bending mirrors M 0 as an optical path deflecting member is disposed. ここで、光路折曲げミラーM 0は第3レンズ群G3の光軸に対して45°で斜設されており、光路折曲げミラーM 2に対して直交して設けられている。 Here, the optical path bending mirror M 0 is obliquely disposed by 45 ° with respect to the optical axis of the third lens group G3, it is provided perpendicular to the optical path bending mirror M 2. この構成により、第1結像光学系G 1及び光路折曲げミラーM 2を介した光束が第1面からの光束の進行方向と同方向となるため、第1面と第2面とを平行な配置とすることができる。 With this configuration, since the light beam through the mirror M 2 Bending the first imaging optical system G 1 and the optical path folding is the same direction as the traveling direction of the light beam from the first surface, parallel to the first and second surfaces it can be a Do arrangement. この構成により、第1面及び第2面をそれぞれ保持し、かつそれぞれ走査させるための機構の構成が容易となる利点がある。 With this configuration, the first and second surfaces respectively held, and there is an advantage that the configuration is easy mechanism for scanning respectively.
なお、図2において、光路折曲げミラーM 0と光路折曲げミラーM 2とを一体の部材で構成しても良い。 In FIG. 2, the optical path bending mirror M 0 and the optical path bending mirror M 2 may be constituted by an integral member. この構成の場合には、互いに直交する光路折曲げミラーM 0の反射面と光路折曲げミラーM 2の反射面との加工が容易となり、この角度の維持が容易となる利点がある。 In the case of this configuration, it becomes easy to process the reflection surface and the optical path deflection reflecting surface of the mirror M 2 of the optical path bending mirror M 0 are orthogonal to each other, there is an advantage that the maintenance of this angle becomes easy. また、一体に構成する場合には、光路折曲げミラーM 0 ,M 2の小型化を図ることができ、レンズの配置の自由度を向上させることができる利点がある。 Further, when configuring integrally, it is possible to reduce the size of the optical path bending mirror M 0, M 2, there is an advantage that it is possible to improve the flexibility of arrangement of the lenses.
また、図3は、本発明による反射屈折光学系のさらに別の配置を示す図である。 3 is a diagram showing still another arrangement of the catadioptric optical system according to the present invention. なお、図3においては、図1と同様の機能を有する部材には同一の符号を付してある。 In FIG. 3, members having the same functions as those in FIG. 1 are denoted by the same reference numerals.
図3において、図1の例とは異なる点は、第2結像光学系中の第5レンズ群G5と第6レンズ群G6との間に、第5レンズ群G5の光軸に対して(第6レンズ群G6の光軸に対して)45°で斜設された光路偏向部材としての光路折曲げミラーM 3を配置した点である。 3, differences from the example of Figure 1, between the fifth lens group G5 in the second imaging optical system and the sixth lens group G6, the optical axis of the fifth lens group G5 ( It lies in that the optical path bending mirror M 3 as an optical path deflecting member which is obliquely disposed with the optical axis with respect to) 45 ° in the sixth lens group G6 is arranged. この構成により、レンズ群G 22から射出されて第2面に到る光束の進行方向が、第1面から第1結像光学系へ入射する光束の進行方向と同方向となるため、第1面と第2面とを互いに平行な配置とすることができる。 By this configuration, the traveling direction of the light beam reaches the second surface is emitted from the lens group G 22 becomes the the same direction as the traveling direction of the light beam incident from the first surface to the first imaging optical system, the first it can be a plane and a second plane and parallel to each other. この構成により、第1面及び第2面をそれぞれ保持し、かつそれぞれ走査させるための機構の構成が容易となる利点がある。 With this configuration, the first and second surfaces respectively held, and there is an advantage that the configuration is easy mechanism for scanning respectively.
また、図3の例では、第1結像光学系G1の第10レンズ群G10から光路折曲げミラーM 2へ向かう光束の進行方向と、第2結像光学系G2中の光路折曲げミラーM 3から第6レンズ群G6へ向かう光束の進行方向とを互いに逆方向とするように、光路折曲げミラーM 2 ,M 3を配置しているため、反射屈折光学系自体をコンパクトに構成することができる。 Further, in the example of FIG. 3, the traveling direction of the light beam directed from the tenth lens group G10 of the first imaging optical system G1 in the optical path bending mirror M 2, the optical path bending mirror M of the second in the imaging optical system G2 from 3 and the traveling direction of the light beam directed to the sixth lens group G6 to the opposite directions, since the mirror M 2, M 3 bend the optical path folding arranged, configuring the catadioptric optical system itself compact can. 特に、この構成によれば、第1面と第2面との間隔を短くすることができる利点があり、露光装置全体のコンパクト化を図ることができる。 In particular, according to this configuration, there is an advantage that it is possible to shorten the distance between the first surface and the second surface, it is possible to reduce the size of the entire exposure apparatus. さらに、図3の例では、光路折曲げミラーM 2を第1結像光学系が形成する中間像の近傍に配置することができるため、光路折曲げミラーM 2の小型化を実現でき、光学系の配置の自由度を増すことができる。 Further, in the example of FIG. 3, it is possible to arrange the light path deflection mirror M 2 in the vicinity of the intermediate image by the first imaging optical system is formed, it can realize miniaturization of the optical path bending mirror M 2, an optical it is possible to increase the degree of freedom of the arrangement of the system.
更に、図2に示す実施例においては、第1面の法線と第2面の法線とが重力方向に対して直角をなすように配置することが好ましい。 Further, in the embodiment shown in FIG. 2, it is preferable that the normal of the normal and the second surface of the first surface is arranged to form a right angle to the direction of gravity. この様に配置すると、第1面、第2面及び最も精度が要求される凹面鏡M 1が重力による非対称な変形を受けなくなるので、大型のフォトマスクやガラスプレートを用いて投影露光する際に有利になる。 When arranged in this manner, the first surface, the concave mirror M 1 to the second surface and the most accuracy is required is not subjected to asymmetrical deformation due to gravity, advantageous for projection exposure using a large-size photomask or glass plate become.
また、図3に示す実施例においては、第1面及び第2面が水平方向となるように光学系を配置すると、重力によって非対称な変形を受ける光学素子が少なくなる。 Further, in the embodiment shown in FIG. 3, the first and second surfaces are arranged an optical system such that the horizontal direction, an optical element for receiving the asymmetric deformation by gravity is reduced. それ故、第1面及び第2面が水平方向で、第1面を第2面よりも上方となるように配置することが好ましい。 Therefore, in the first and second surfaces is horizontal, it is preferable to arrange the first surface such that the above the second face. 特に、第2結像光学系中の第5レンズ群G5以外は非対称な変形を受けないため、この様な配置とすると、光学性能上非常に有利である。 In particular, other than the fifth lens group G5 in the second imaging optical system because it does not undergo asymmetric deformation, when such arrangement is very advantageous on optical performance. ここで、凹面鏡M 1が水平に配置されているということは、殊更有効である。 Here, the fact that the concave mirror M 1 is disposed horizontally is especially effective.
また、上記各実施例では、凹面鏡M 1付近又は第2結像光学系中(特に、第5レンズ群G5と第6レンズ群G6との間)に開口絞りを配置することが可能である。 Further, in the above embodiments, the concave mirror M 1 or near the second imaging optical system in (in particular, between the fifth lens group G5 and the sixth lens group G6) it is possible to place an aperture stop. また、このとき、照明光学系の開口数NAと投影光学系の開口数NAとの比であるシグマ(σ)値を、可変にすることも可能である。 At this time, the sigma (sigma) value which is the ratio of the numerical aperture NA of the numerical aperture NA of the illumination optical system projection optical system, it is also possible to variably. 本実施例中では、機械的干渉が起こりにくい第2光学系に配置することが特に好ましい。 In the present embodiment, it is particularly preferable to arrange the second optical system that mechanical interference hardly occurs.
また、開口絞りを配置する代わりに、様々な特殊フィルターを配置することによって、焦点深度を深くすることが可能である。 Further, instead of arranging the aperture stop, by placing various special filter, it is possible to deepen the depth of focus. 特殊フィルターの一例の図を示した図8を参照しながら説明する。 Referring to FIG. 8 shows a diagram of an example of a special filter will be described.
下記の各数値実施例は、物体側及び像側がテレンセントリックな光学系となっていて、物体側の各点からの主光線はある光軸の一点で交わるようになっている。 Each numerical example below, the object side and the image side have a terrain centric optical system is adapted to intersect at one point of the optical axis with the principal ray from each point on the object side. この様な状況で主光線が光軸と交わる一点を含む平面を、フーリエ変換面と呼び、特殊フィルターは、このフーリエ変換面に配置する。 A plane principal rays in such a situation includes a point which intersects the optical axis, called the Fourier transform plane, a special filter is disposed on this Fourier transform plane. 以下に示す各数値実施例では、凹面鏡M 1付近又は第2結像光学系中にフーリエ変換面を設けることが可能である。 In each numerical example shown below, it is possible to provide a Fourier transform plane in the concave mirror M 1 or near the second imaging optical system. フーリエ変換面では、光軸から放れた特定の位置によって回折光の次数が決まる。 The Fourier transform plane, the order of diffracted light is determined by the particular location Hore from the optical axis. 光軸から離れるほど次数は高くなる。 Order as the distance from the optical axis increases. 一般的な投影露光光学系は、0次及び1次の回折光を取り入れている。 General projection exposure optical system incorporates a zero-order and first-order diffracted light. これより、図8(a)及び(b)に示す様に、0次光の成分が存在する半径r 1の光軸付近の領域FAと、半径r 1から半径r 2までの1次光(及びそれ以上の次数の回折光)が存在する開口部周辺付近の領域FBとに、フィルターの領域を分割する。 From this, as shown in FIG. 8 (a) and (b), a region FA in the vicinity of the optical axis of a radius r 1 that there are components of the 0 order light, 1 order light from radius r 1 to a radius r 2 ( and a region FB around the periphery of an opening there are more orders of diffracted light), divides the area of the filter.
図8(c)に示す通り、同心円状に分割したフィルターは、中心部領域FAがS偏光のみを透過し、周辺部領域FBがP偏光のみを透過するように偏光膜を形成する。 As shown in FIG. 8 (c), the filter divided concentrically in the center area FA transmits only S-polarized light, a peripheral area FB to form a polarizing film to transmit only P-polarized light. 当然のことながら、中心部領域FAがP偏光、周辺部領域FBがS偏光のみを透過するようにしても構わない。 Of course, the central part area FA P-polarized light, the peripheral region FB is may be transmitted through only the S-polarized light. また、このとき、中心部領域FAの屈折率が、周辺部領域FBの屈折率より低くなるようにする。 At this time, the refractive index of the central portion area FA, to be lower than the refractive index of the peripheral area FB.
上記に示した構成により、特殊フィルターの周辺部領域FBを透過した光束は、焦点面で通常の結像を行う。 The configuration shown in, the light beam passing through the peripheral area FB of the special filter performs normal imaging at the focal plane. 一方、特殊フィルターの中心部領域FAを透過した光束は、屈折率が低いために、通常の焦点面よりレンズから遠ざかる位置に焦点を結ぶ。 On the other hand, the light beam transmitted through the central region FA of the special filter, due to the low refractive index, a focal point at a position away from the normal of the focal plane from the lens. ここで、周辺部領域FBを透過した光束と中心部領域FAを透過した光束とは偏光状態が違うため、それぞれの光束が干渉することは無い。 Here, since the polarization state different from the light beam transmitted through the light beam and the center region FA passing through the peripheral area FB, never respective light beams interfere. これにより、焦点深度を深くすることが可能となる。 Thereby, it becomes possible to deepen the depth of focus. また、焦点深度を深くする技術としては、特開昭61−91662号公報、特開平5−234850号公報、特開平6−120110号公報、特開平6−124870号公報、特開平7−57992号公報及び特開平7−57993号公報等に開示された技術があり、それぞれ本発明に適用可能である。 As the deeply technical focal depth, JP 61-91662, JP-A No. 5-234850, JP-A No. 6-120110, JP-A No. 6-124870, JP-A No. 7-57992 There are publications and Hei 7-57993 Patent Publication technique disclosed in, is applicable to the present invention, respectively. 特に、この様な技術は、孤立パターンを形成するときに有効である。 In particular, such techniques are effective in forming an isolated pattern.
ここで、凹面鏡M 1付近に特殊フィルターを配置した場合、第2結像光学系の方に開口絞りを配置して、開口数を変化させることが可能である。 Here, the case of arranging a special filter in the vicinity of the concave mirror M 1, by arranging the aperture stop towards the second imaging optical system, it is possible to change the numerical aperture. また、第2結像光学系に特殊フィルターを配置し、凹面鏡M 1付近に開口絞りを配置することも可能である。 Further, a special filter disposed in the second imaging optical system, it is also possible to arrange the aperture stop in the vicinity of the concave mirror M 1. このように、本実施例中における反射屈折光学系は、開口絞りと特殊フィルターとを同一光学系中に分離して配置することができ、空間配置において有利である。 Thus, a catadioptric system in the present embodiment may be arranged to separate the aperture stop and the special filter in the same optical system is advantageous in spatial arrangement.
また、中間像を形成する場所に絞りを置けば、この絞りは、視野絞りとすることができる。 Also, if you put a stop to a location for forming an intermediate image, the diaphragm may be a field stop. 各実施例の場合、第1結像光学系と第2結像光学系の間に、視野絞りを設けることが可能である。 For each example, between the first imaging optical system and the second imaging optical system, it is possible to provide a field stop. 上記実施例では、図1から図3までに示すように、中間像のできる位置がミラーの付近となっている。 In the above embodiment, as shown in FIGS. 1 to 3, a position which can intermediate image is in the vicinity of the mirror. このため、ミラーの付近に絞りを配置すればよい。 Thus, it may be arranged a stop near the mirror. 絞りを配置する構成としては、例えば、図9に示す例がある。 The construction of arranging the aperture, for example, there is an example shown in FIG.
視野絞りを設ける場合は、図9に示す例のごとく、光路折り曲げミラーM 2をなるべく第1結像光学系G1の第10レンズ群G10の近傍となるように配置する。 In the case of providing the field stop, as in the example shown in FIG. 9, to place the mirrors M 2 folded optical path as possible the vicinity of the tenth lens group G10 of the first imaging optical system G1. これにより、中間像が形成される面が、光路折り曲げミラーM 2近傍から第2結像光学系中の第5レンズ群G5よりとなる。 Thus, the surface intermediate image is formed becomes the than the fifth lens group G5 from the mirror M 2 near the optical path bending in the second imaging optical system. この様な配置とすることにより、光路折り曲げミラーM 2と第1結像光学系G1の第10レンズ群G10と視野絞り機能とが機械的干渉が起こりにくくなる。 By virtue of the above arrangement, the mirror M 2 folded optical path and the tenth lens group G10 and the field stop function of the first imaging optical system G1 is less likely to occur mechanical interference. そして、中間像を形成する面に、視野絞りSを配置する。 Then, the surface forming an intermediate image, placing the field stop S. 視野絞りSが動くことにより、中間像のできる範囲が変化する。 By field stop S moves, the range that can intermediate image is changed. これにより、最終的に第2面上で像の形成される範囲が変化するとになる。 Thus, ultimately range formed in the image on the second surface is to vary.
また、視野の大きさを変化させるものとして、特開昭57−192024号公報、特開昭60−30132号公報、特開昭60−45252号公報、実開昭62−124845号公報、米国特許第4,473,293号公報及び米国特許第4,474,463号公報等に開示された技術があり、それぞれ応用可能である。 Further, as for changing the size of the field of view, JP 57-192024, JP-Sho 60-30132, JP-Sho 60-45252, JP-Utility Model 62-124845, JP-US There is the technique disclosed in the 4,473,293 Patent Publication and US Patent No. 4,474,463 Publication, respectively applicable.
上記のように、可動な遮光部材を場合に応じて動かすことにより視野絞りを達成する方法以外に、大きさの異なるミラー自体を交換することにより、視野絞りの代わりとすることができる。 As described above, in addition to the method of achieving the field stop by moving as the case of the movable light shielding member, by exchanging different mirror itself sizes, it can be substituted for the field stop.
なお、図9に示す開口可変な視野絞りの形状は、四角形のみならず、円弧状及び四角以上の多角形状にも適用できることは言うまもない。 The opening variable field stop having a shape shown in FIG. 9, not square only, is no or say can be applied to an arc shape and a square or polygonal shape. また、投影光学系中に視野絞りを配置することができるため、照明光学系に配置された所謂レチクルブラインドを無くすこと可能であることも言うまでもない。 The projection it is possible to arrange a field stop in the optical system, it is also naturally be possible to eliminate the placed-called reticle blind in the illumination optical system.
次に、本発明の反射屈折光学系の数値実施例を説明する。 Next, a description will be given of numerical examples of the catadioptric optical system of the present invention. 以下の数値実施例においては、レンズ配置を図4及び図6に示すように、展開光路図で表す。 In the following numerical examples, the lens arrangement as shown in FIG. 4 and FIG. 6, represented in exploded optical path diagram. 展開光路図においては、反射面は透過面として表され、レチクルRからの光が通過する順に各光学要素が配列される。 In development optical path diagram, the reflecting surface is represented as a transmissive surface, the optical elements are arranged in the order in which light from the reticle R passes. また、凹面反射鏡の反射面では、平面の仮想面を使用している。 Further, the reflecting surface of the concave reflecting mirror, are using virtual surface plane. そして、レンズの形状及び間隔を表すために、例えば図4に示すように、レチクルRのパターン面を第0面として、レチクルRから射出された光がウェハーWに達するまでに通過する面を順次第i面(i=1,2,‥‥)としている。 Then, in order to represent the shape and spacing of the lenses, for example, as shown in FIG. 4, the pattern surface of the reticle R as the 0 surface, the frame sequential light emitted from the reticle R passes before reaching the wafer W the i-th surface (i = 1,2, ‥‥) is set to. ここで、第i面の曲率半径ri の符号は展開光路図の中でレチクルRに対して凸面を向ける場合を正にとる。 Here, the sign of the curvature radius ri of the i-th surface takes exactly the case of directing the convex surface to the reticle R in the expansion optical path diagram. また、第i面と第(i+1)面との面間隔をdi とする。 Also, the surface interval between the i-th surface and the (i + 1) -th surface, and di. また、硝材として、SiO2 は溶融石英を表し、CaF2 は蛍石を表す。 Further, as the glass material, SiO2 represents fused quartz, CaF2 represents fluorite. 溶融石英及び蛍石の使用基準波長(193.0nm)に対する屈折率は次のとおりである。 Refractive index to use reference wavelength (193.0 nm) of fused quartz and fluorite are as follows.
また、分散値1/νは、次の通りである。 Further, the dispersion value 1 / [nu, is as follows.
但し、実施例中での分散値は、使用基準波長(193.0nm)に対する±0.1nmの分散値である。 However, the dispersion values in the examples is the variance value of ± 0.1 nm with respect to the operating reference wavelength (193.0 nm).
図4を参照して本発明による第1実施例を説明する。 Referring to FIG. 4 illustrating a first embodiment according to the present invention. 図4は第1実施例における反射屈折光学系の展開光路図である。 Figure 4 is a developed optical path diagram of the catadioptric optical system in the first embodiment.
図4に示す各レンズ群のレンズ構成について説明すると、第7レンズ群G7は、レチクルR側から順に、第8レンズ群G8である両凸形状の正レンズL1 と第9レンズ群G9である両凹形状の負レンズL2 とから構成される。 Referring to the lens configuration of each lens group shown in FIG. 4, the seventh lens group G7, in order from the reticle R side, a positive lens L1 having a biconvex shape which is the eighth lens G8 is the ninth lens group G9 both concave composed negative lens L2 Prefecture. 第7レンズ群G7に続いて配置される第3レンズ群G3は、第10レンズ群G10である両凸形状の正レンズL3 と、第11レンズ群G11であるレチクルR側に凸面を向けたメニスカス形状の負レンズL4 と、第12レンズ群G12である両凸形状の正レンズL5 とから構成される。 Meniscus third lens group is arranged subsequent to the seventh lens group G7 G3 includes a positive lens L3 having a biconvex shape which is a tenth lens group G10, with a convex surface facing the reticle R side is first lens group G11 a negative lens L4 shape, and a positive lens L5 and a bi-convex, which is the second lens subunit G12. 更に、第3レンズ群G3に続いて配置される第4レンズ群G4は、レチクルR側に凹面を向けたメニスカス形状の負レンズL6 と凹面鏡M1 とから構成される。 The fourth lens group G4 is arranged subsequent to the third lens group G3 is composed of a negative lens L6 and a concave mirror M1 Metropolitan meniscus shape with a concave surface facing the reticle R side.
ここで、レチクルRからの光束は、第8レンズ群G8、第9レンズ群G9、第10レンズ群G10、第11レンズ群G11、第12レンズ群G12、第4レンズ群G4、第12レンズ群G12、第11レンズ群G11、第10レンズ群G10を順に経由して、第3レンズ群G3と第7レンズ群G7との間にレチクルRの中間像を形成する。 Here, the light beam from the reticle R, the eighth lens G8, ninth lens group G9, tenth lens group G10, the first lens subunit G11, the second lens subunit G12, the fourth lens group G4, a lens subunit G12, the first lens subunit G11, via a tenth lens group G10 in order to form an intermediate image of the reticle R between the third lens group G3 and the seventh lens group G7.
第5レンズ群G5は、この中間像側から順に、屈折力の弱い両凸形状の正レンズL 7と、両凸形状の正レンズL 8と、両凹形状の負レンズL 9と、中間像側に凸面を向けたメニスカス形状の負レンズL 10と、両凹形状の負レンズL 11と、中間像側に凹面を向けたメニスカス形状の負レンズL 12と、両凸形状の正レンズL 13と、両凸形状の正レンズL 14とから構成される。 The fifth lens group G5 includes, in order from the intermediate image side, a positive lens L 7 of weak refractive power biconvex positive lens L 8 biconvex, a negative lens L 9 biconcave, intermediate image a negative lens L 10 of a meniscus shape with a convex surface on the side, a negative lens L 11 of double concave, a negative lens L 12 of a meniscus shape having a concave surface facing the intermediate image, a biconvex positive lens L 13 When, and a positive lens L 14 and a bi-convex.
また、この第5レンズ群G5に続いて配置される第6レンズ群G6は、中間像側から順に、中間像側に凸面を向けたメニスカス形状の正レンズL 15と、中間像側に凸面を向けたメニスカス形状の正レンズL 16と、中間像側に凹面を向けたメニスカス形状の負レンズL 17と、両凸形状の正レンズL 18と、中間像側に凸面を向けたメニスカス形状の負レンズL 19と、中間像側に凸面を向けたメニスカス形状の正レンズ成分L 20と、屈折力の弱い両凹形状の負レンズL 21と、中間像側に凸面を向けたメニスカス形状の負レンズL 22と、中間像側に凸面を向けたメニスカス形状の正レンズL 23とから構成される。 The sixth lens group G6 is arranged subsequent to the fifth lens group G5 includes, in order from the intermediate image side, a positive lens L 15 of a meniscus shape with a convex surface faces the intermediate image, the convex surface faces the intermediate image a positive lens L 16 of meniscus, a negative lens L 17 of a meniscus shape with a concave surface facing the intermediate image side, a positive lens L 18 of a biconvex shape, a negative meniscus shape with a convex surface faces the intermediate image a lens L 19, a positive lens component L 20 of the meniscus shape with a convex surface facing the intermediate image side, a negative lens L 21 weak biconcave refractive power, a negative meniscus lens having a convex surface faces the intermediate image and L 22, and a positive lens L 23 Metropolitan of meniscus shape with a convex surface faces the intermediate image.
以下の表1に本実施例の諸元の値を掲げる。 It shows numerical data of the embodiment shown in Table 1 below. 本実施例において、全系の倍率は1/4倍(縮小)であり、ウェハW側の開口数NAは0.57である。 In the present embodiment, the magnification of the entire system is 1/4 (reduction), the numerical aperture NA of the wafer W side is 0.57. そして、図1に示す如く、本実施例の反射屈折光学系は、レチクルR上における露光領域は、縦方向が光軸Axからの物体高の範囲が52から76までの長さ24で、横方向が120の矩形状である。 Then, as shown in FIG. 1, the catadioptric optical system of this embodiment, the exposure area on the reticle R, the vertical direction from the object height ranging from the optical axis Ax 52 to 76 length 24, the horizontal direction is 120 rectangular.
なお、表1に示す本実施例においては、光路折曲げミラーM2 は、第7面と第28面とに位置する。 In the present embodiment shown in Table 1, the optical path bending mirror M2 is located in the seventh surface and the 28 surface. また、表1では、凹面鏡M1 は第18面に相当する。 Further, in Table 1, the concave mirror M1 corresponds to the eighteenth surface. 本実施例中において第17面(仮想面)と第18面とを反射面(屈折率=−1)とすることで、 図4に示す展開光路図を作成可能とした。 With seventeenth surface in the present embodiment the reflecting surface and a plane (virtual plane) and the eighteenth surface (refractive index = -1), made it possible to create a deployment optical path diagram shown in FIG.
条件対応値を以下に示す。 The conditions corresponding value in the following.
図5 (a)は第1実施例の縦収差図であり、 図5 (b)は第1実施例の倍率色収差図、 図5 (c)は第1実施例の横収差図である。 5 (a) is a longitudinal aberration diagram of a first embodiment, FIG. 5 (b) the lateral chromatic aberration diagram of a first embodiment, FIG. 5 (c) is a lateral aberration diagram of the first embodiment. 各収差図中において、NAは開口数を表し、Yは像高を表す。 During these graphs, NA represents the numerical aperture, Y denotes an image height. また、符号J、P及びQは、波長がそれぞれ193.0nm、192.9nm及び193.1nmであることを示す。 Further, reference numeral J, P and Q indicate that wavelength are each 193.0 nm, 192.9Nm and 193.1Nm. そして、 図5 (a)において、球面収差中において、破線は正弦条件違反量を表し、非点収差中においては、破線はメリジオナル像面、実線はサジタル像面をそれぞれ表す。 Then, in FIG. 5 (a), in in the spherical aberration, the dashed line represents an offense against sine condition, during the astigmatism, the broken line a meridional image surface, the solid line represents a sagittal image plane, respectively. 図5 (c)に示す横収差図において、各コマ収差図中の上部に記載される数字は、物体高を表し、特に、RANDは物体高0のときを表している。 In the transverse aberration chart shown in FIG. 5 (c), the numbers described upper in the coma diagram, represents the object height, in particular, RAND indicates when the object height 0.
図5 (a) 〜 (c)に示す諸収差図より、本実施例では、0.57という大きな開口数NAでありながら、広い領域において諸収差が良好に補正されていることが分かる。 From various aberrations shown in FIG. 5 (a) ~ (c) , in the present embodiment, it is understood that while a large numerical aperture NA of 0.57, various aberrations in a wide area are well corrected. また、 図5 (a) 〜 (c)に示す諸収差図より、本実施例では、波長幅0.1nmの範囲において軸上及び倍率の色収差も良好に補正されていることが分かる。 Further, from the aberration diagrams shown in FIG. 5 (a) ~ (c) , in the present embodiment, it can be seen that are well corrected even longitudinal chromatic and magnification within the range of wavelength width 0.1 nm.
図6を参照して本発明による第2実施例を説明する。 Referring to FIG. 6 illustrating a second embodiment according to the present invention. 図6は第2実施例による反射屈折光学系の展開光路図である。 6 is a developed optical path diagram of the catadioptric optical system according to the second embodiment.
図6に示す各レンズ群のレンズ構成について説明すると、レチクルR側から順に、第10レンズ群G10、第11レンズ群G11、第12レンズ群G12から構成される。 Referring to the lens configuration of each lens group shown in FIG. 6, in order from the reticle R side, the tenth lens group G10, the first lens subunit G11, composed of the second lens subunit G12. ここで、第10レンズ群G10は、両凸形状の正レンズL1 と、両凹形状の負レンズL2 と、両凸形状の正レンズL3 と、レチクルR側に凹面を向けたメニスカス形状の負レンズL4 から構成される。 Here, the tenth lens group G10, a positive lens L1 biconvex, a negative lens L2 biconcave positive lens L3 having a biconvex shape, a negative meniscus lens having a concave surface facing the reticle R side consisting of L4. また、第11レンズ群G11は、レチクルR側に凸面を向けたメニスカス形状の負レンズL5 である。 Further, an eleventh lens group G11 is a negative lens L5 of a meniscus shape with a convex surface facing the reticle R side. 第12レンズ群G12は、両凸形状の正レンズL6 と、レチクルR側に凸面を向けたメニスカス形状の負レンズL7 と、両凸形状の正レンズL8 とから構成される。 Twelfth lens group G12 is composed positive lens L6 biconvex, and the negative lens L7 having a meniscus shape with a convex surface facing the reticle R side, a positive lens L8 and a bi-convex. 更に、第3レンズ群G3に続いて配置される第4レンズ群G4は、 負レンズL 9と凹面鏡M1 とから構成される。 Further, the fourth lens group is arranged subsequent to the third lens group G3 G4 is composed of a negative lens L 9 and the concave mirror M1 Prefecture.
ここで、レチクルRからの光束は、第10レンズ群G10、第11レンズ群G11、第12レンズ群G12、第4レンズ群G4、第12レンズ群G12、第11レンズ群G11、第10レンズ群G10を順に経由して、第3レンズ群G3とレチクルRとの間にレチクルRの中間像を形成する。 Here, the light beam from the reticle R, the tenth lens group G10, the first lens subunit G11, the second lens subunit G12, the fourth lens group G4, a lens subunit G12, the first lens subunit G11, the tenth lens group via G10 in order to form an intermediate image of the reticle R between the third lens group G3 and the reticle R.
第5レンズ群G5は、この中間像側から順に、中間像に凹面を向けたメニスカス形状の負レンズL 10と、両凸形状の正レンズL 11と、両凹形状の負レンズL 12と、両凸形状の正レンズL 13と、中間像側に凹面を向けたメニスカス形状の負レンズL 14と、両凸形状の正レンズL 15と、両凸形状の正レンズL 16ととから構成される。 The fifth lens group G5 includes, in order from the intermediate image side, a negative lens L 10 of a meniscus shape with a concave surface facing the intermediate image, a positive lens L 11 of double-convex shape, a negative lens L 12 of double-concave shape, a positive lens L 13 of double-convex shape, a negative lens L 14 of a meniscus shape with a concave surface facing the intermediate image side, a positive lens L 15 of double-convex shape, and a positive lens L 16 Toto biconvex that.
また、この第5レンズ群G5に続いて配置される第6レンズ群G6は、中間像側から順に、中間像側に凸面を向けたメニスカス形状の正レンズL 17と、両凸形状の正レンズL 18と、両凹形状の負レンズL 19と、中間像側に凸面を向けたメニスカス形状の正レンズL 20と、中間像側に凸面を向けたメニスカス形状の負レンズL 21と、中間像側に凸面を向けたメニスカス形状の正レンズ成分L 22と、中間像側に凹面を向けたメニスカス形状の負レンズL 23と、両凸形状の正レンズL 24と、中間像側に凸面を向けたメニスカス形状の正レンズL 25とから構成される。 Further, the fifth sixth lens group G6 is arranged subsequent to the lens group G5 includes, in order from the intermediate image side, a meniscus shape with a convex surface faces the intermediate image and a positive lens L 17, a biconvex positive lens and L 18, a negative lens L 19 of double-concave shape, a positive lens L 20 of a meniscus shape with a convex surface facing the intermediate image side, a negative lens L 21 of a meniscus shape with a convex surface faces the intermediate image, the intermediate image towards a positive lens component L 22 of a meniscus shape with a convex surface on the side, a negative lens L 23 of a meniscus shape with a concave surface facing the intermediate image side, a positive lens L 24 of a biconvex shape, a convex surface faces the intermediate image It was composed of the positive lens L 25 Metropolitan meniscus. また、このとき、開口絞りaは、第5レンズ群G5と第6レンズ群G6との間に配置される。 At this time, the aperture stop a is disposed between the fifth lens group G5 and the sixth lens group G6.
以下の表2に本実施例の諸元の値を掲げる。 It shows numerical data of the embodiment shown in Table 2 below. 本実施例において、全系の倍率は1/4倍(縮小)であり、ウェハWー側の開口数NAは0.57である。 In the present embodiment, the magnification of the entire system is 1/4 (reduction), the numerical aperture NA of the wafer W over the side is 0.57. 本実施例の反射屈折光学系は、レチクルR上における露光領域は、縦方向が光軸Axからの物体高の範囲が48から72までの長さ24で、横方向が120の矩形状である。 Catadioptric optical system of this embodiment, the exposure area on the reticle R, the vertical direction in the length 24 from the object height ranging from the optical axis Ax 48 to 72, the lateral direction is 120 rectangular .
なお、表2では、凹面鏡M1 は第20面に相当する。 In Table 2, the concave mirror M1 corresponds to a 20 surface. 本実施例中において第19面(仮想面)と第20面とを反射面(屈折率=−1)とすることで、 図6に示す展開光路図を作成可能とした。 With the nineteenth surface in the present embodiment the reflecting surface and a plane (virtual plane) and the twentieth surface (refractive index = -1), made it possible to create a deployment optical path diagram shown in FIG.
図7 (a)は第2実施例の縦収差図であり、 図7 (b)は第2実施例の倍率色収差図、 図7 (c)は第2実施例の横収差図である。 7 (a) is a longitudinal aberration diagram of a second embodiment, FIG. 7 (b) the lateral chromatic aberration view of a second embodiment, FIG. 7 (c) is a lateral aberration diagram of a second embodiment. 各収差図中において、NAは開口数を表し、Yは像高を表す。 During these graphs, NA represents the numerical aperture, Y denotes an image height. また、符号J、P及びQは、波長がそれぞれ193.0nm、192.9nm及び193.1nmであることを示す。 Further, reference numeral J, P and Q indicate that wavelength are each 193.0 nm, 192.9Nm and 193.1Nm. そして、 図7 (a)において、球面収差中において、破線は正弦条件違反量を表し、非点収差中においては、破線はメリジオナル像面、実線はサジタル像面をそれぞれ表す。 Then, in FIG. 7 (a), in the in the spherical aberration, the dashed line represents an offense against sine condition, during the astigmatism, the broken line a meridional image surface, the solid line represents a sagittal image plane, respectively. 図7 (c)に示す横収差図において、各コマ収差図中の上部に記載される数字は物体高を表し、特に、RANDは物体高0のときを表している。 In the transverse aberration chart shown in FIG. 7 (c), the numbers described on top in each coma chart indicates the object height, in particular, RAND indicates when the object height 0.
図7 (a) 〜 (c)に示す諸収差図より、本実施例では、0.57という大きな開口数NAでありながら、広い領域において諸収差が良好に補正されていることが分かる。 From various aberrations shown in FIG. 7 (a) ~ (c) , in the present embodiment, it is understood that while a large numerical aperture NA of 0.57, various aberrations in a wide area are well corrected. また、 図7 (a) 〜 (c)に示す諸収差図より、本実施例では、波長幅0.1nmの範囲において軸上及び倍率の色収差も良好に補正されていることが分かる。 Further, from the aberration diagrams shown in FIG. 7 (a) ~ (c) , in the present embodiment, it can be seen that are well corrected even longitudinal chromatic and magnification within the range of wavelength width 0.1 nm.
以上の通り、本発明による各実施例によれば、非常に大きな開口数でありながら、凹面鏡M 1が小さく、広い露光領域において諸収差が良好に補正された反射屈折光学系を提供することが可能である。 As described above, according to the embodiments of the present invention, while a very large numerical aperture, small concave mirror M 1, that is to provide a satisfactorily corrected catadioptric optical system aberrations in a wide exposure area possible it is. そして、第1実施例中では、凹面鏡M 1は、直径を330程度とすることができる。 Then, during the first embodiment, the concave mirror M 1 can be a 330 about a diameter. 第2実施例中では、凹面鏡M 1は、直径を210程度とすることができる。 In the in the second embodiment, the concave mirror M 1 can be about 210 in diameter. また、各実施例の屈折レンズの直径についても、小型化することが可能となっている。 As for the diameter of the refractive lens of each embodiment, it is possible to miniaturize.
また、上述の各実施例では、光路偏向手段としての光路折曲げミラーM 2が第1結像光学系G1が形成する中間像の近傍に配置される構成であるため、光路折曲げミラーM 2に対する第1及び第2結像光学系G1,G2の偏心誤差の影響を少なくできる。 In the embodiments described above, since the mirror M 2 Bending optical path folding as an optical path deflecting means is constituted by the first imaging optical system G1 is disposed near the intermediate image formed, the optical path bending mirror M 2 the first and the influence of the eccentricity error of the second imaging optical system G1, G2 for can be reduced. また、上記各実施例では、光路折曲げミラーM 2の反射面に達する光束の径が小さくなるため、光路折曲げミラーM 2自体の小型化を図ることができる。 Further, in the above embodiments, since the diameter of the light beam reaching the reflecting surface of the optical path bending mirror M 2 becomes smaller, it is possible to reduce the size of the optical path bending mirror M 2 itself. 従って、光路折曲げミラーM 2による光束の遮蔽を少なくできるため、露光領域の拡大化を達成できる利点もある。 Therefore, it is possible to reduce the shielding of the light flux by the optical path bending mirror M 2, an advantage that can be achieved enlargement of the exposure region.
さらに、各実施例では、光路折曲げミラーM 2によって、第1結像光学系G1からの光束を90°偏向させた後に第2結像光学系G2へ導く構成としているため、第1結像光学系G1と第2結像光学系G2との偏心調整が容易に行なえる利点がある。 Furthermore, in each embodiment, the optical path bending mirror M 2, since the a configuration that leads to the second imaging optical system G2 after the light beam is deflected 90 ° from the first imaging optical system G1, the first imaging eccentricity adjustment of the optical system G1 and the second imaging optical system G2 is easily is advantageous performed.
また、各実施例においては、第2結像光学系G2中の第5レンズ群G5と第6レンズ群G6との間に開口絞りaを配置できるため、この開口絞りaを開口径可変となるように構成すれば、NA可変(或いはσ可変)による露光をも達成できる。 In each embodiment, since the fifth lens group G5 of the second in the image-forming optical system G2 can be disposed an aperture stop a between the sixth lens group G6, the the aperture stop a aperture diameter variable if configured, it can also be achieved exposure by NA variable (or σ variable).
尚、上述の第1及び第2実施例の光路折曲げミラーM 1の代わりに、ビームスプリッタを用いる構成をとる場合には、レチクルR上の光軸Axからの物体高が0〜72の範囲内(第1実施例では〜76の範囲内まで使用可能)を用いる一括露光を行うこともできる。 Incidentally, in place of the optical path bending mirror M 1 in the first and second embodiments described above, when a configuration using a beam splitter, range object height of 0-72 from the optical axis Ax on the reticle R inner (in the first embodiment usable to within to 76) can be performed batch exposure using.
以上の通り本発明によれば、凹面鏡の口径の小型化をも達成することができ、なお且つ、作動距離を十分に確保したうえで高い開口数を実現できる。 According to the above as the present invention, miniaturization of the diameter of the concave mirror can also be achieved, even and can realize a high numerical aperture in terms of the sufficient working distance.
【図1】本発明の基本的な光学系の構成の概略を示す平面図である。 1 is a plan view schematically showing a basic optical system configuration of the present invention.
【図2】本発明の別の態様の構成の概略を示す平面図である。 Is a plan view showing a schematic configuration of another embodiment of the present invention; FIG.
【図3】本発明の別の態様の構成の概略を示す平面図である。 3 is a plan view showing a schematic configuration of another embodiment of the present invention.
【図4】本発明の第1実施例による反射屈折光学系の展開光路図である。 4 is a developed optical path diagram of the catadioptric optical system according to a first embodiment of the present invention.
【図5】第1実施例による反射屈折光学系の諸収差図である。 5 is graphs showing various aberrations of the catadioptric optical system according to the first embodiment.
【図6】本発明の第2実施例による反射屈折光学系の展開光路図である。 6 is a developed optical path diagram of the catadioptric optical system according to a second embodiment of the present invention.
【図7】第2実施例による反射屈折光学系の諸収差図である。 7 is graphs showing various aberrations of the catadioptric optical system according to the second embodiment.
【図8】実施例における特殊フィルターの一例を示した図である。 8 is a diagram showing an example of a special filter in the embodiment.
【図9】実施例における視野絞りの一例を示した図である。 9 is a diagram showing an example of a field stop in the embodiment.
前記第1反射屈折結像光学系と前記第2屈折結像光学系との合成倍率は縮小倍率であることを特徴とする反射屈折光学系。 Catadioptric system, wherein the synthetic magnification of the second refractive imaging optical system and the first catadioptric imaging system is a reduction ratio.
前記第2屈折結像光学系は縮小倍率を有することを特徴とした請求項1記載の反射屈折光学系。 Claim 1 catadioptric optical system according to the, wherein the second refractive imaging optical system having a reduction magnification.
前記第1光路偏向部材を前記第1面と前記第3レンズ群G3との間の光路中であって、前記第3レンズ群G3の光軸からそれた位置に配置することを特徴とする請求項1又2記載の反射屈折光学系。 Wherein said first an optical path deflecting member is an optical path between the third lens group G3 and the first surface, characterized in that arranged at a position that the optical axis of the third lens group G3 claim 1 or 2 catadioptric optical system according.
前記第2屈折結像光学系は、正屈折力の第5レンズ群G5と、正屈折力の第6レンズ群G6とを有することを特徴とする請求項1乃至3のいずれか一項に記載の反射屈折光学系。 Said second refractive imaging optical system, a fifth lens group G5 having a positive refractive power, according to any one of claims 1 to 3, characterized in that it has a positive refracting sixth lens group force G6 catadioptric optical system.
前記第5レンズ群G5と前記第6レンズ群G6との間の光路中に開口絞りを配置することを特徴とする請求項4記載の反射屈折光学系。 Claim 4 catadioptric optical system, wherein the arranging the aperture stop in the optical path between the fifth lens group G5 and the sixth lens group G6.
該第7レンズ群G7は、前記第1面側から順に、正屈折力の前群と負屈折力の後群とを有することを特徴とする請求項1乃至5のいずれか一項に記載の反射屈折光学系。 Is said seventh lens group G7, in order from the first surface side, according to any one of claims 1 to 5, characterized in that it has a rear group of the front group and the negative refractive power of the positive refractive power catadioptric system.
前記第1光路偏向部材を前記第3レンズ群G3と前記第7レンズ群G7との間の光路中であって、前記第7レンズ群G7の光軸からそれた位置に配置することを特徴とする請求項6に記載の反射屈折光学系。 And characterized in that arranged at a position a light path, which then the seventh lens group G7 of the optical axis between the first optical path deflecting member and said third lens group G3 and the seventh lens group G7 catadioptric optical system according to claim 6.
を満足することを特徴とする請求項1乃至7のいずれか一項に記載の反射屈折光学系。 Catadioptric optical system according to any one of claims 1 to 7, characterized by satisfying the.
前記第2屈折結像光学系を構成する光学材料は、互いに分散値の異なる少なくとも二種類の光学材料であることを特徴とする請求項1乃至8のいずれか一項に記載の反射屈折光学系。 The optical material second constituting a refractive imaging optical system, a catadioptric optical system according to any one of claims 1 to 8, characterized in that at least two kinds of optical materials having different different dispersion values .
前記第2屈折結像光学系中の前記第6レンズ群G6は、低分散ガラスから構成される正レンズ成分を含むことを特徴とする請求項4又は5に記載の反射屈折光学系。 The second refraction imaging the sixth lens group G6 in the optical system is a catadioptric optical system according to claim 4 or 5, characterized in that it comprises a positive lens component composed of a low dispersion glass.
前記第1面と前記第2面とを平行にするために、前記第1面と前記第1反射屈折結像光学系中の前記第3レンズ群G3との間に前記第1面からの光を偏向させる第2光路偏向部材を配置することを特徴とする請求項1乃至10のいずれか一項に記載の反射屈折光学系。 Wherein in order to collimate the first surface and the second surface, the light from the first surface between the third lens group G3 of the first surface and the in the first catadioptric imaging system catadioptric optical system according to any one of claims 1 to 10, characterized in that arranging the second optical path deflecting member that deflects the.
前記第1面の法線と前記第2面の法線とが重力方向に対して直角をなすように前記第1面及び前記第2面を配置することを特徴とする請求項11記載の反射屈折光学系。 Reflection of claim 11, wherein the the normal normal to the second surface of the first surface to place the first surface and the second surface to form a right angle to the direction of gravity refractive optics.
前記第1面と前記第2面との配置を平行にするために、第1光路偏向部材と前記第2結像光学系中の前記第5レンズ群G5と前記第6レンズ群G6の間に、前記第1光路偏向部材を経由した光を偏向させる第3光路偏向部材を配置することを特徴とする請求項4又は5に記載の反射屈折光学系。 To parallel arrangement of the first surface and the second surface, between the said fifth lens group G5 in the first optical path deflecting member and the in the second imaging optical system sixth lens group G6 , catadioptric optical system according to claim 4 or 5, characterized in that arranging the third optical path deflecting member that deflects the light through the first optical path deflecting member.
前記第1面と前記第2面とを水平に配置し、且つ前記第1面を前記第2面よりも上方に配置することを特徴とする請求項13記載の反射屈折光学系。 Wherein the first surface and the second surface is disposed horizontally, and claim 13 catadioptric optical system according to the first surface, characterized in that disposed above the second surface.
前記第1反射屈折結像光学系と前記第2屈折結像光学系との間に形成される中間像の位置に、前記第2面上の像形成領域の大きさが可変となる視野絞りを設けることを特徴とする請求項1乃至14のいずれか一項に記載の反射屈折光学系。 The position of the intermediate image is formed between the second refractive imaging optical system and the first catadioptric imaging system, a field stop size of the image forming region on the second surface is variable catadioptric optical system according to any one of claims 1 to 14, wherein the providing.
前記第1反射屈折結像光学系中の前記凹面鏡付近の光路中又は前記第2屈折結像光学系の光路中に、焦点深度を深くするフィルターを設けることを特徴とする請求項1乃至15のいずれか一項に記載の反射屈折光学系。 In the optical path of the optical path or the second refractive imaging optical system near said concave mirror in said first catadioptric imaging system, according to claim 1 to 15, characterized by providing a filter that depth of focus catadioptric optical system according to any one.
前記第2屈折結像光学系の光路中に、開口絞りを配置することを特徴とする請求項1乃至15のいずれか一項に記載の反射屈折光学系。 Wherein the second intermediate refractive imaging optical path of the optical system, a catadioptric optical system according to any one of claims 1 to 15, characterized in that the aperture stop is disposed.
前記投影光学系が請求項1乃至請求項17のいずれか一項に記載の反射屈折光学系であることを特徴とする投影露光装置。 Projection exposure apparatus, wherein the projection optical system is a catadioptric optical system according to any one of claims 1 to 17.


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Trout Unlimited Calls for Action on Drilling Regulation Changes Proposed by SRBC
by Ben Kryzinski - Thursday, Aug 18th, 2011
Historic Penns Creek, a tributary of the Susquehanna River. (Photo: B. Kline)
Trout Unlimited issued to its members today a call to action regarding changes to gas drilling regulations proposed by the SRBC (Susquehanna River Basin Commission). According to Trout Unlimited, these changes pose a significant threat to water quality and aquatic life in the Susquehanna River Basin, which includes some of the finest trout rivers and streams in Pennsylvania. Many of the proposed changes identify an ease of administrative burdens on the SRBC, rather than scientific or case-proven rationale, as their motivating factor.
One of the key proposed changes is the extension of the life-cycle of water withdrawal permits for drilling operations from the current 5 to 15 years, citing the aforementioned "ease of administrative burden" which would result from lengthening permit life. Trout Unlimited argues that once drilling operations come online in neighboring New York and Maryland, the burden of dramatically increased water withdrawal from area streams and rivers could have dire consequences. The current 5 year permit cycle, argues TU, would allow for reasonable re-evaluation of the burden of water withdrawal on resources in the Susquehanna River Basin.
Another, perhaps more important change, proposed by the SRBC is the institution of "approval by rule" which, in short, allows approval of operations which meet certain criteria to be "fast-tracked" to the executive director for direct approval, without requiring review by the commission. Not only does this reduce the amount of scrutiny applied by the SRBC, it removes the ability for the public to provide input on newly proposed operations.
Also included in the SRBC's proposed changes are the allowance of well-to-well transfers of waste water from drilling operations. These allowances could also fall under the "approval by rule" process, removing public scrutiny on operations that involve "the transfer of fluids that may contain heavy metals, chemicals, salts and radioactive elements".
Leading Environmental Group Calls Pennsylvania Drilling Plan 'Full of Loopholes'
Gas Companies Targeting State Parks for Drilling
To learn more about the proposed changes, or to respond to TU's call to action, visit the Trout Unlimited Action Center.
Susquehanna River Basin
SRBC
Chad Shmukler replied on Thu, 08/18/2011 - 20:52 Permalink
I get it. Put an entire major watershed at risk so the SRBC doesn't have to hire a few more paper pushers.
Rock solid.
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The family of a Redcar dad who died after a fall at work say they are "unable to accept the scant version of events" released by Saudi Arabian authorities.
The precise details of how Stephen Morten died while working on a construction site are unknown, an inquest has heard.
But his family say they find it "inconceivable" that Mr Morten, who was "highly experienced", would have had "such a complete disregard for his own safety" as was alleged in statements released to the coroner.
They added that they were "extremely upset" that it has "proved almost impossible to establish" how Mr Morten died, as the coroner was forced to rely on statements from people who had not witnessed what happened and which they believe contain "inconsistencies".
Now they want a formal procedure to be developed with Saudi Arabia for UK coroners to obtain information so other families "do not suffer such further misery over and above their tragic loss".
At the time of his death in December 2011 Mr Morten was working as a supervisor at a power station which was being constructed in Rabigh.
Saudi police classified the 49-year-old's death as accidental and coroner Michael Sheffield recorded an accident verdict at an inquest held at Teesside Coroner's Court.
But he said evidence supplied by Saudi authorities was "limited" and did not mention electrical burns to Mr Morten's hands, which he believes were "not likely to have killed him but caused him to fall".
The dad-of-five from Redcar sustained multiple injuries following a fall. Statements received from Saudi were read out, which said that Mr Morten fell 176m while replacing a rope for a platform in a chimney which was being built.
The statements said Mr Morten used a basket normally used to hoist tools and failed to wear a harness despite being told to. But Mr Sheffield said these statements had not been confirmed by any other means.
Dr Jan William Lowe conducted the post mortem examination at Middlesbrough's James Cook University Hospital when Mr Morten's body was returned to the UK.
He told the court that the details he received were "brief", adding no post-mortem examination was held in Saudi, which was "unusual".
Charring was found to Mr Morten's hands and while Dr Lowe said electrocution was "unlikely" to be the cause of his death, he believed they occurred shortly beforehand as "he would have been severely incapacitated as a result of them and would not have been able to work".
He said he would have expected Mr Morten to have sustained a greater number of injuries if he had fallen 176m, adding he was surprised there was no skull or pelvis fracture.
Shortly before he travelled to Saudi, Mr Morten was diagnosed with a heart murmur, but there was no evidence this contributed to his death. A toxicology analysis showed there was no drugs or alcohol in his system.


What do Adam and Eve, out-of-control goth dolls, Etta James, multiple personalities, and Metallica have in common? Innervation Dance Cooperative has brought them all together in their upcoming dance concert, Our Own Devices. IDC's roots are in theater and contemporary dance, and the many choreographers and dancers come from wildly different backgrounds. These qualities always lead to an eclectic show, and the company's mainstays of narrative dancing and a high-energy, multi-layered aesthetic bring it all together. In this concert, each of the eight choreographers presents the audience with a different struggle and shows us what happens when groups and individuals are left to their "own devices." The subjects range from a comedic and sultry reinterpretation of Eve's relationship with the Snake, to the frustration, bliss, and heartbreak involved in pursuing a man, to a portrayal of a woman whose mind created multiple personalities to deal with childhood abuse, to goth-esque dolls running amok in the dollhouse. There are eye-opening moments of intensity and belly-shaking moments of comedy, thought-provocation and good times guaranteed.
Dance novices and aficionados will appreciate the accessible style and, because IDC's roots are in theater, will come to know and empathize with each character without necessarily knowing the difference between a pirouette and a plie. The music choices, from Etta James to John Lennon, from Bob Seger to Metallica, also contribute to the comfort level. IDC's mission is to present dance to ever-widening audiences in Chicago -- striving to draw people from the already faithful and the soon-to-be faithful Chicago dance community. This is a great opportunity for you to come join!
Links Hall, 3435 N. Sheffield Ave., Chicago, IL. November 13 & 14 @ 8:00 p.m. and November 15 @ 7:00 p.m. $15 ($10 students and seniors). Click here or call 773.281.0824 for tickets.


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St. James Church Office: 741-5300 M-F, 9-4
St. James Fish Fry 2023
February 24,
March 3, 10, 17, 24, 31
St. James Fish Fry 2023 February 24, March 3, 10, 17, 24, 31St. James Fish Fry 2023 February 24, March 3, 10, 17, 24, 31St. James Fish Fry 2023 February 24, March 3, 10, 17, 24, 31
St. James Fish Fry 2023St. James Fish Fry 2023St. James Fish Fry 2023
Hours: 4:30 - 7:30 p.m.
Dine in, order carry-out OR
Drive Thru Pick-Up when using
the app: MyMenuHelper
Sign Ups will begin January 15th. Please sign up to volunteer. This button will send you to our volunteer sign up pages. You can sign up for 1 or all 6 weeks. Feel free to comment any requests for where you'd like to work or any specialized hours.
Click here to volunteer
Order Online Today for the Fish Fry
Fridays Only During Lent - 2023 Dates: February 24, March 3, 10, 17, 24 and 31.
No Fish Fry on Good Friday. HOURS: 4:30 p.m. - 7:30 p.m.
CLICK HERE TO ORDER FOR PICK-UP TODAY!
Menu - All items and Pricing subject to change due to supply
All dinners are served with 2 sides: 1. choice of Mac-n-Cheese or French Fries, AND 2. choice of Greens Beans, Applesauce or Coleslaw.
Fried Fish - beer-battered cod
Fish dinners are served with choice of white, rye or salted rye bread.
6 pieces of fried shrimp with your choice of 2 sides.
served with French Fries and Coleslaw.
Small Fried Fish Basket
one 4 oz. portion of fried fish.
Large Fried Fish Basket
two 4 oz. portions of fried fish.
Choice of white, rye or salted rye bread
LaRosa's Cheese Pizza - large
Slice of Cheese Pizza
Mac-n-Cheese
A "mystery dessert" will be included for only $1.00 if you order through the app or by phone! Desserts will be 2 of a selection of homemade cookies, brownies or rice krispie treats. Dine-in customers may purchase a variety of desserts from the dessert table.
Coke, Diet Coke, Sprite or bottled water - $1.00 and Little Hugs for $ .50.
St. James Fish Fry
3565 Hubble Rd, Cincinnati, Ohio 45247, United States
St. James Church Office: (513) 741-5300
Fridays Only During Lent
2023 Dates: February 24, March 3, 10, 17, 24 and 31.
No Fish Fry on Good Friday.
To Call Church Hall for Carry-Out Orders during Fish Fry Hours, Call 513-741-5311
For DRIVE-THRU, CONTACT-LESS pickup, download the "MyMenuHelper" app to your smart phone. Search for St. James Fish Fry. Order and pay by your phone and pick up at the labeled curbside pickup spots in the lower church parking lot at your designated time!
For the past 16 years, our mission has been to provide a high-quality Lenten meal at a reasonable price
for our parish and community while promoting fellowship and fun.
Copyright © 2023 St. James Fish Fry - All Rights Reserved.


text:
Martin Huckerby
Keywords: Tolerance, discrimination, human rights, gender, on-line, investigative reporting, Freedom of expression and diversity, Peace journalism, English, print, on-line, All Regions, All Organizations
British journalist, with wide experience as a reporter and news editor on leading British newspapers – for the last dozen years, an editorial consultant, training journalists and advising news organizations around the globe.
From 2005 to 2007, editorial director of the human rights reporting programme, working with the Great Britain-China Centre and Tsinghua University, producing the first manual of human rights reporting for Chinese journalists.
Half a year in Afghanistan (2004-5) as managing editor of the new national Pajhwok news agency (IWPR for USAID).
UN media consultant in Bangladesh (2001-2), for the UNDP's Parliament and Democracy project.
Martin Huckerby CV.doc


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Schools in South Africa
Understanding the fundamentals
Expat parents moving to South Africa have a wide range of high-quality options for educating their children. South African schools are classified as either public and government-funded or independent schools and privately run.
In practice, there are also semi-private schools, meaning that while they are ultimately accountable to the government, they are partially self-funded and are often able to offer better facilities and a higher standard of education than other government schools.
Although there are 11 official languages in South Africa, English is most commonly spoken in major cities such as Cape Town and Johannesburg and is therefore the teaching medium in the vast majority of schools. That is, however, where uniformity ends – schools in South Africa vary widely in terms of cost, quality and curriculum.
While most expats choose to send their children to private or international schools, the decision depends on a number of factors, such as location, cost, the availability of places at the school and the intended length of the family's stay in South Africa.
Are you moving abroad?
Before venturing to another country, make sure you have a health insurance plan you can rely on. Our international health insurance plans offer comprehensive health cover for when you are in your home country and abroad.
Public schools in South Africa
Public schools in South Africa partly rely on the government for funding and supplies. No-fee schools are fully funded by the government, and only exist in the poorest areas of the country. All other public schools are partly funded by school fees paid by parents, which are generally much lower than those of private schools. Families who cannot afford the fees can apply to the government for funding. Each province is responsible for its schools and, as such, standards vary immensely depending on the efficiency and wealth of the province.
Unfortunately, many public schools in South Africa, especially those in poorer, more rural areas, suffer as a result of poor funding, lack of government monitoring and a lack of suitably qualified teachers. Because of such shortcomings, parents who can afford it usually opt to send their children to private or semi-private schools.
Private schools in South Africa
Private education in South Africa is much more expensive than public education, but standards are high. These schools are attended mostly by children from middle and high income families. In South Africa's large cities, expats will be spoilt for choice in terms of private schooling options.
Many private schools have religious origins and aim to provide pupils with a spiritual foundation to complement their academic offerings. Others subscribe to a particular learning philosophy, such as Waldorf or Montessori.
Similar to other countries, private schools generally have better facilities, smaller classes and a larger selection of extra-curricular activities than public schools.
Private schools are extremely popular in South Africa and can therefore be difficult to get into. The application process for these schools often includes a test and an interview.
International schools in South Africa
There are a number of international schools in South Africa that offer a variety of globally recognised curricula, such as that of the UK, the US, Germany, France or the International Baccalaureate.
Many expats, especially those who are only relocating to South Africa for a short period of time, opt to send their children to an international school. This allows for a smoother transition, as the student will continue following a familiar curriculum from their home country. International schools are also a great way to connect with fellow expat families.
There are two major downsides to international schooling. Firstly, fees can be exorbitant and, secondly, it can often be difficult to secure a place in some of the more popular schools. For the best chance at being admitted, parents should start the application process as early as possible. To mitigate costs, those moving to South Africa for work should try to negotiate a school allowance into their relocation package.
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to South Africa
Obtaining a visa for South Africa
Healthcare in South Africa


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Arts & Culture, news, Social Justice No Comments
JR's New Houston Bowery Mural Takes Aim at 'Guns in America'
October 26, 2018 By Summer Cartwright
(Photos: Summer Cartwright)
It's a weird sight: families and high school tour groups smiling and posing against a wall of activists with guns slung on their shoulders, or signs held high above their heads.
But that strange sight might continue, at least for the month during which "The Gun Chronicles: A Story of America" is up at the Houston Bowery Wall in Soho. The image is a compilation of portraits photographed by French street artist JR, and it's featured on the front cover of Time magazine's November issue.
Depending on where one stands on the sidewalk, a certain stance on gun regulation might seem prominent; people and activists on both sides of the divided aisle are scattered throughout the art. But no single side or group is the focus; instead, it's the conversation.
Or, more accurately, it's the many conversations Time reporters, editors, producers and JR had with 245 people in Texas, St. Louis and Washington, DC. Mia Tramz, managing editor for Life VR and producer of the project, said the cover (and mural) have been in development since early summer.
After its debut in New York, the mural will come to many other states, Tramz said, in hopes that it will fuel civil conversation and prompt viewers to explore further into gun legislation. The issue is "something we, as a media organization, have to report on again and again," she said.
325 million people. More than 265 million guns. 35,000 deaths a year. And one 227-year-old constitutional right. To tell this uniquely American story, we worked with @time. In three U.S. cities profoundly affected by guns—Dallas, St. Louis and Washington, D.C.—we invited people to share their views and describe their experiences in a search for common ground. In all, we filmed and photographed 245 people—hunters and activists, teachers and police officers, parents and children—to create this mural for TIME's November 5, 2018, cover. Explore the full project at TIME.com/guns-in-america @time
A post shared by JR (@jr) on Oct 25, 2018 at 7:13am PDT
Survivors of shootings, mayors, senators, pastors, principles, moms, dads, brothers and sisters are among the people featured in the mural and the interactive feature at Time.com, as are groups like Black Lives Matter, Moms Demand Action, the NRA and Texas Gun Rights. Notable appearances include former U.S. Rep. Gabrielle Giffords, Republican majority whip Steve Scalise and Forward Through Ferguson organizer David Dwight IV. The youngest person pictured is 7 and the oldest is 77.
Basically, Time made it so there's a spot for 245 people with different opinions at the table — and room for the hundred, thousands or millions of people that might see, watch, hear, or take selfies with them.
Tags: Arts + Culture, East Village
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Like many of you, breast cancer has touched us personally, affecting many near and dear people in our lives. But it was our mom's experience with breast cancer that inspired us to stand up and find a way to support others on their journey. After a very long, frustrating and fruitless day of shopping for bras during her recovery from a lumpectomy and radiation, we quickly realized there had to be a better option and—if we could not find it—we would create it. And in that one shopping trip, an idea was born.
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Human error. It has been a part of our game since its birth. Refs making big calls 'in the moment' based on their own judgement and expertise.
Frustrating at times, especially when incorrect decisions are made against you. Accepted however because at the end of the day you win some, you lose some. It has contributed to some of the greatest rivalries in football and is just a part of our game. No matter the importance of the match or experience of the ref, human error can eventually be forgiven.
Since the implementation of the Video Assistant Referee into the Hyandai A-league, fans have been unforgiving of referees. Human error has become irrelevant and a non-excuse due to the power of the machine.
When Melbourne Victory took the lead over Newcastle in the 2017/18 season grand final, I could not have cared less that James Donachie was offside. I was thankful to the machine for failing and I was thankful for human error. Ordinarily the human would have been criticised but forgiven because making those calls during important moments is a tough gig. But that game won't be remembered as anything other than 'that time the technology failed our game' and this is not what football is about.
Last night, Kurt Ams was offered the use of the VAR to confirm or rectify his initial judgement that Corey Brown had fouled Bruno Fornaroli. After reviewing the footage, it was clear to all that Kurt Ams was wrong to stand by his initial call for a penalty. But what is most disappointing is that he actually had the chance to prove just why VAR deserves a place in our game.
But what is its place if humans are still to have the final call? Can human error be forgiven as easily when there is a machine available to them at all times? After last night, the answer to that is clear. There is no place for human error anymore, leaving implications for our game's future if refs are going to continue making the wrong calls. At least until round 2, Melbourne Victory's season opener will be spoken about as the game where Kurt Ams had no excuse.
If we are going to persist with the implementation of this technology in our sport, then there is no place for human error anymore. But as a passionate supporter of my club and the game, I say take the technology away and trust our refs. When the machine still does not have the final say at the end of the day, really what's the point?


A HomeLight concierge will reach out on Gaetan Ruggeri's behalf within 3 mins during business hours.
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from your phone calls and enjoy HiFi stereo music in daily life.
microphone both suit to listen to music and make phone calls,it is fine workmanship, beautiful appearance,worth for this price.
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A:This bluetooth earphone is not only suit for Android phone,but also suit for ios apple iphone system.
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A:the color of this bluetooth earphone all shows in the store,we can't provide other colors.
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A:This model bluetooth earphone is great noise cancelling headphone.
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A:This model bluetooth earphone is sweafproof,can't take it to the water.
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The Moon Garden of Agra, located right across the river from the Taj Mahal, is one of the best places to see the famous structure. The garden features remains of what many people believe was the start of a replica Taj Mahal to be built in black. While that has never been confirmed, there are ruins in this garden of a structure and it is an amazing place to walk the lush trees and plant life while gazing upon India's jewel, the Taj Mahal.
Thank you to Josh McNair of Our Unique World for permission to share the photograph.
I hadn't heard before that the garden across the river is called the Garden of the Moon. Any idea why? I'm visiting Agra in November and can't wait to see this beautiful building!
The most perfect monument I have ever seen. My job gave me the privilege to see it at all times and the best time for me has been during sunrise and sunset. And sipping a cup of coffee from the balcony of the hotel Amarvilas during full moon. Truly mesmerising and magical!


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Taking A Minute
Yesterday's release of the minutes of the ECB's December 14 policy meeting, being perceived by the market as more hawkish, prompted a move higher in the value of the euro (EURUSD, EURGBP, EURJPY). But perhaps one issue that traders might wish to consider is that while the minutes said "the language pertaining to various dimensions of the monetary policy stance and forward guidance could be revisited early in [2018]" the ECB also added that while there was a widely shared view that "communication would need to evolve gradually, without a change in sequencing." Specifically stipulating 'without a change in sequencing' might indicate an attempt by the ECB to temper a wider market reaction to a seemingly slightly more hawkish approach.
While the ECB seems committed to updating forward guidance "in line with evolving data with a view to avoiding more abrupt or disorderly adjustments at a later stage," it likely still wouldn't want to trigger a near-term surge in the value of the euro which would be disadvantageous to its hopes of generating inflation of close to but below 2 per cent in the euro zone, or render euro zone manufacturers who export outside the currency bloc less competitive. The ECB's problem is that the currency market will, as is usually the case, be the ultimate arbiter of the euro's external value. The risk, as the ECB no doubt were reminded of on Thursday, is that the currency market doesn't feel it needs to wait for the ECB to make up its mind. The currency market can act if it collectively concludes a direction of travel is quietly being established. Whether, on this occasion, December's ECB minutes are enough to underpin a more sustained broad rally in the euro's value through the end of this week and into the next is a judgement only individual traders can make.
Written by Neal Kimberley, External Currency Analyst.
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Serendipity is Sweet: It's Someone's Birthday!
Happy birthday to my beautiful, sweet, sassy seven year old! I can hardly believe how grown up you have become, especially over the past year. I love you to pieces!! I am so proud of your kind heart, your loving nature and your creative mind. I love that you are friendly and sweet, but also strong and level-headed. Those traits will serve you well as you get older (as will having learned to fend off two brothers!). Don't go changing sweet sister.
I wish you all the very best this year and always.
What a sweet birthday girl! Great photos as always.
happy birthday to your princess!!
Awwwww- Happy Birthday to her. 7 is a BIG DEAL!!!!
What a beauty she is. Happy birthday!
She looks so happy! Happy Birthday!!
Beautiful Lady ;) ! Happy Birtday ! Thanks for passing by ..