Nikon Corporation

Hajime Ichikawa

Shigeru Nakayama

Makoto Uehara

Shigeru Kato

Takashi Gemma

Takahiro Yamamoto

Hiroshi Ichihara

Masahiko Yomoto

Tetsuji Onuki

Masami Ebi

Takashi Genma

Bruce Jacobsen

A method of manufacturing a projection optical system ( ) for projecting a pattern from a reticle to a photosensitive substrate, comprising a surface-shape-measuring step wherein the shape of an optical test surface ( ) of an optical element ( ) which is a component in the projection optical system is measured by causing interference between light from the optical surface ( ) and light from an aspheric reference surface ( ) while the optical test surface ( ) and said reference surface ( ) are held in integral fashion in close mutual proximity. A wavefront-aberration-measuring step is included, wherein the optical element is assembled in the projection optical system and the wavefront aberration of the projection optical system is measured. A surface correction calculation step is also included wherein the amount by which the shape of the optical test surface should be corrected is calculated based on wavefront aberration data obtained at the wavefront-aberration-measuring step and surface shape data obtained from the surface-shape-measuring step. The method also includes a surface shape correction step wherein the shape of the optical test surface is corrected based on calculation performed at the surface correction calculation step. Surface shape measuring interferometer systems and wavefront-aberration-measuring interferometer systems ( J- Q) used in performing the manufacturing method are also disclosed.

Interferometer that measures aspherical surfaces

Apparatus and methods are disclosed for measuring the surface topography of a test surface, such as a spherical or aspherical surface of a refractive or reflective optical element. The test surface is measured by detecting the state of interference fringes generated by interference of a reference light beam and a measurement light beam that interacts (e.g., reflects from) the test surface. The reference and measurement beams are produced by a point light source having a reflective surface. The point light source is disposed between a source of input light and the test surface. The measurement beam (after interacting with the test surface) and the reference beam are caused to interfere with each other to produce a first interference-fringe state. The distance between the point light source and the test surface can be changed between production of the first interference-fringe state and production of a second interference-fringe state. The profile of the test surface is determined by analyzing the resulting interference fringes. A null element can be used to convert a spherical wavefront of the measurement beam into an aspherical wavefront corresponding to the aspherical test surface, or to convert an aspherical wavefront generated by reflection of a spherical wavefront from an aspherical test surface into a spherical or planar wavefront.

Interferometric apparatus and methods for measuring surface topography of a test surface

A magnification calibration apparatus includes an optical system optically coupled to an object surface for forming an image of the object surface, a detector for detecting the image of the object surface, and a movable support for supporting the object surface, the movable support being capable of laterally moving the object surface by a predetermined distance from a first lateral position to a second lateral position. The magnification calibration apparatus further includes a reference point recognition unit for, at each of the first and second lateral positions of the object surface, detecting the position of the image of an imaginary reference point on the object surface as a position in a detector coordinate system fixed to the detector in accordance with the image detected by the detector, and a computation unit for deriving a correspondence between an object coordinate system at the object surface and the detector coordinate system from the detected positions of the image in the detector coordinate system at the first and second lateral positions of the object surface and from the predetermined distance by which the object surface is moved from the first lateral position to the second lateral position by the movable support.

Magnification calibration apparatus and shape measuring system

A non-spherical surface shape measuring device and method that measures the shapes of object surfaces that have rotationally symmetrical non-spherical surface shapes on the basis of relative deviation values from the shape of a reference surface, the non-spherical surface shape measuring device includes a measuring means for obtaining relative deviation values between a reference surface and an object surface by measuring corresponding sampling points on the surfaces of the reference surface and the object surface and storing predetermined coefficients of variables prior to measurement. A first operating means approximates the partial differential coefficients for the predetermined variables and models the relative displacement, between the object surface and the reference surface and the XY-coordinates of the sampling points, into functional equivalents of the partial differential coefficients. A second operating means approximates the relative displacement between the object surface and the reference surface and a third operating means corrects the relative deviation values according to the relative displacement approximated by the second operating means.

Non-spherical surface shape measuring device

A method of measuring a surface shape of a target surface, and a lens manufacturing process for manufacturing a lens having a surface shape figured to high-precision. The method and process includes the steps of first, interferometrically measuring the surface shape of the target surface or the lens surface. Then second, measuring a surface shape of a prototype target surface. Then third, determining a rotationally symmetric error component of the difference between the target surface shape or the lens surface shape and the prototype target surface shape. Then fourth, expressing the rotationally symmetric error as a sum of two components, one being slowly varying and the other being a remainder. The slowly varying component is at least determined by performing the third step, while the remainder component is determined by performing the first step.

Shape measurement method and high-precision lens manufacturing process

A method is provided for deriving an absolute surface profile of an object having a rotationally symmetric component and a rotationally asymmetric component using a detection system for measuring a relative surface profile of the object with respect to a predetermined reference surface. The method includes the steps of positioning the object to a first predetermined position relative to the detection system, rotating the object around a predetermined measurement axis of rotation at the first predetermined position, acquiring data indicating the relative surface profile of the object with respect to the predetermined reference surface at each of a plurality of rotational positions of the object during the rotating step, averaging the data acquired in the acquiring step over the plurality of rotational positions to derive a rotationally averaged data, and processing the rotationally averaged data and the data indicating the relative surface profile of the object at at least one of the plurality of rotational positions of the object to derive the rotationally asymmetric component of the absolute surface profile of the object. The method further includes the steps of translating the object to a second predetermined position relative to the detection system, acquiring data indicating the relative surface profile of the object at the second predetermined position, and processing the data indicating the relative surface profile of the object at the second predetermined position and at least one of the rotationally averaged data and the data indicating the relative surface profile at at least one of the plurality of rotational positions of the object to derive the rotationally symmetric component of the absolute surface profile of the object, the data processing using a polynomial best fitting method for the data indicating the relative surface profile at the second predetermined position.

Apparatus and method for wavefront absolute calibration and method of

An apparatus and a method for detecting the temperature of a substrate, and for controlling the radiation-annealing of the substrate, for example, measures the intensity of infrared light from the substrate when the substrate is irradiated by measuring infrared light and also when the substrate is not irradiated by the infrared light. The temperature is calculated from the transmissivity and emissivity of the substrate, which are calculated from the intensity measurements.

Method for measuring temperature of semiconductor substrate and

An apparatus for annealing a substrate includes a plurality of annular light sources concentric about a predetermined axis, a holder for placing the substrate such that the substrate receives radiation from the plurality of annular light sources and is substantially perpendicular to the predetermined axis, and a measuring device having a measuring optical system with an optical axis substantially aligned with the predetermined axis. The measuring device is adapted to receive radiation through the measuring optical system from the substrate placed on the holder and to detect a temperature distribution of the substrate.

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Yokohama, Japan

Hajime Ichikawa