Nikon Corporation

Issey Tanaka

Hiroyuki Hiraiwa

Naomasa Shiraishi

Soichi Owa

Yasuhiro Omura

Shigeru Hirukawa

Mikihiko Ishii

Hitoshi Matsuzawa

Katsuya Miyoshi

Takeshi Suzuki

Nobutaka Magome

Hiroki Jinbo

Norio Komine

Seishi Fujiwara

Toshihiko Ozawa

Kazuhiro Nakagawa

Shunsuke Niisaka

Jun Takano

An exposure apparatus illuminates a pattern with an energy beam and transfers the pattern onto a substrate via a projection optical system. The exposure apparatus includes a substrate stage on which the substrate is mounted and that moves within a two-dimensional plane holding the substrate. A supply mechanism supplies liquid to a space between the projection optical system and the substrate on the substrate stage. A recovery mechanism recovers the liquid and an auxiliary recovery mechanism recovers the liquid which could not be recovered by the recovery mechanism.

Exposure apparatus and device manufacturing method

An exposure apparatus illuminates a pattern with an energy beam and transfers the pattern onto a substrate via a projection optical system. The exposure apparatus includes a substrate stage on which the substrate is mounted that moves within a two-dimensional plane holding the substrate. The apparatus also includes a supply mechanism that supplies liquid to a predetermined spatial area which includes a space between the projection optical system and the substrate on the substrate stage, and an adjustment unit that adjusts exposure conditions based on temperature information on the liquid between the projection optical system and the substrate.

An optical system attains good optical performance without substantially receiving the effects of birefringence even when using an optical material having intrinsic birefringence. An optical system that includes at least one radiation transmissive member that transmits light having a wavelength of 200 nm or less has an optical axis that substantially coincides with a crystal axis [100] or a crystal axis optically equivalent to the crystal axis [100]. In addition, an optical system can include: a first group of radiation transmissive members that transmits light having a wavelength of 200 nm or less and having an optical axis that substantially coincides with a crystal axis [100] or a crystal axis optically equivalent to the crystal axis [100]; and a second group of radiation transmissive members that transmits light having a wavelength of 200 nm or less and having an optical axis that substantially coincides with a crystal axis [100] or a crystal axis optically equivalent to the crystal axis [100]; wherein the first group of radiation transmissive members and the second group of radiation transmissive members have a positional relationship rotated substantially 45&#xb0; about the optical axis relative to each other.

Optical system and exposure apparatus provided with the optical system

A projection optical system, which forms a reduced image of a first surface onto a second surface, has excellent optical performance without substantially being affected by birefringence despite the use of optical material having intrinsic birefringence. This is done by suitably arranging certain crystal axes of radiation transmissive members that make up the projection optical system relative to the optical axis of the projection optical system, and by suitably arranging the certain crystal axes of the radiation transmissive members relative to the crystal axes of other radiation transmissive members in the projection optical system.

Projection optical system and an exposure apparatus with the projection optical system

In a projection optical system for projecting and transferring a pattern on a projection original R onto a photosensitive substrate W, one or a plurality of lenses having an in-homogeous radial refractive index about the optical axis are used, while one or a plurality of aspheric surfaces for correcting the aberration resulting from the in-homogeousness in refractive index of lenses are provided.

Illumination optical system and method of making exposure apparatus

A projection optical system of the present invention has a first lens group G being positive, a second lens group G being negative, a third lens group G being positive, a fourth lens group G being negative, a fifth lens group G being positive, and a sixth lens group G being positive in the named order from the first object toward the second object, in which the second lens group G comprises an intermediate lens group G between a negative front lens L and a negative rear lens L and in which the intermediate lens group G is arranged to comprise at least a first positive lens being positive, a second lens being negative, a third lens being negative, and a fourth lens being negative in the named order from the first object toward the second object. The present invention involves findings of suitable focal length ranges for the first to the sixth lens groups G to G and an optimum range of an overall focal length of from the second negative lens to the fourth lens with respect to a focal length of the second lens group G .

Exposure apparatus

In a projection optical system having at least two silica glass optical members, a birefringence value is measured at each of points in a plane normal to the optical axis with the center at an intersection of each optical member with the optical axis, a distribution of signed birefringence values in each optical member is obtained by assigning a positive sign to each birefringence value when a direction of the fast axis thereof is a radial direction to the intersection with the optical axis and assigning a negative sign to each birefringence value when the direction of the fast axis thereof is normal to the radial direction, and the optical members are combined with each other so as to satisfy such a placement condition that a signed birefringence characteristic value of the entire projection optical system calculated based on the distributions of signed birefringence values is between &minus;0.5 and &plus;0.5 nm/cm both inclusive. This permits minimization of influence from nonuniform distribution of birefringence values in the optical members on the imaging performance of the projection optical system or on the resolution of projection exposure apparatus and in turn enables provision of the projection optical system with high imaging performance, a production method thereof, and the projection exposure apparatus capable of achieving high resolution.

Projection optical system, production method thereof, and projection exposure apparatus using it

In a method for evaluating the homogeneity of the refractive index of an optical member, the refractive index distribution of the optical member is measured, the measured refractive index distribution is separated into a rotationally symmetric element and a non-rotationally symmetric element in the optical axis direction before or after correction of the power element, and the rotationally symmetric element is further subjected to 2nd/4th-order element correction. Upon execution of such comprehensive evaluation, a photolithography optical member, which can realize a fine, sharp exposure-transfer pattern (e.g., a line width of 0.3 &mgr;m or less) is provided.

Optical member for photolithography, method for evaluating optical member, and photolithography apparatus

A projection optical system of the present invention has a first lens group G.sub.1 being positive, a second lens group G.sub.2 being negative, a third lens group G.sub.3 being positive, a fourth lens group G.sub.4 being negative, a fifth lens group G.sub.5 being positive, and a sixth lens group G.sub.6 being positive in the named order from the first object toward the second object, in which the second lens group G.sub.2 comprises an intermediate lens group G.sub.2M between a negative front lens L.sub.2F and a negative rear lens L.sub.2R and in which the intermediate lens group G.sub.2M is arranged to comprise at least a first positive lens being positive, a second lens being negative, a third lens being negative, and a fourth lens being negative in the named order from the first object toward the second object. The present invention involves findings of suitable focal length ranges for the first to the sixth lens groups G.sub.1 to G.sub.6 and an optimum range of an overall focal length of from the second negative lens to the fourth lens with respect to a focal length of the second lens group G.sub.2.

In a method for evaluating the homogeneity of the refractive index of an optical member, the refractive index distribution of the optical member is measured, the measured refractive index distribution is separated into a rotationally symmetric element and a non-rotationally symmetric element in the optical axis direction before or after correction of the power element, and the rotationally symmetric element is further subjected to 2nd/4th-order element correction. Upon execution of such comprehensive evaluation, a photolithography optical member, which can realize a fine, sharp exposure-transfer pattern (e.g., a line width of 0.3 .mu.m or less) is provided.

Optical member for photolithography, method for evaluating optical

Recent UV-lithography is required to provide a fine and sharp pattern with a line width of 0.5 .mu.m or less. The present invention provides a silica glass member adapted for use as an optical element for UV-lithography, by giving consideration to the RMS value of wave front aberration and the slant element of refractive index, which have not been considered in the art. Also, there is provided a silica glass member excellent in durability to the ultraviolet irradiation, by introduction of hydrogen molecules at the synthesis of the silica glass, instead of using a secondary treatment for hydrogen introduction.

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Yokohama, Japan

Issey Tanaka