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AssigneeCanon Kabushiki Kaisha
InventorMichio Kohno
Estimating the term…
An exposure apparatus wherein a first object is illuminated with slit-like exposure light while the first object and a second object are scanningly moved at a speed ratio corresponding to a projection magnification of a projection optical system such that a pattern of the first object is projected onto the second object through the projection optical system. The apparatus includes an illuminating device for illuminating a mark provided on the first object side with light having the same wavelength as that of the exposure light, wherein light from the mark is incident on the projection optical system whereby a revolutionally asymmetric aberration of the projection optical system due to an exposure is corrected or reduced.
An exposure apparatus wherein a first object is illuminated with slit-like exposure light while the first object and a second object are scanningly moved at a speed ratio corresponding to a projection magnification of a projection optical system such that a pattern of the first object is projected onto the second object through the projection optical system, said apparatus comprising:
An exposure apparatus wherein a first object is illuminated with a slit-like light beam while the first object and a second object are scanningly moved at a speed ratio corresponding to a projection magnification of a projection optical system such that a pattern of the first object is projected onto the second object through the projection optical system, said apparatus comprising:
An exposure apparatus wherein a first object is illuminated with a slit-like light beam while the first object and a second object are scanningly moved at a speed ratio corresponding to a projection magnification of a projection optical system such that a pattern of the first object is projected onto the second object through a projection optical system, said apparatus comprising:
An exposure apparatus for illuminating a first object with exposure light and for projecting a pattern of a first object onto a second object through a projection optical system, said apparatus comprising:
An exposure apparatus for projecting a pattern of a first object onto a second object through a projection optical system, said apparatus comprising:
An exposure apparatus for projecting a pattern of a first object onto a second object through a projection optical system, said apparatus comprising:
Dependencies are inferred from the claim text.
No related US applications are recorded in the indexed filing history.
Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring: testing optical components
Mask projection systems: scanning exposure, i.e. relative movement of patterned beam and workpiece during imaging
Of optical system: temperature
Photomechanical production of textured or patterned surfaces
Term ended 30 Aug 2020 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
This invention relates to an exposure method and a scanning exposure apparatus using the same. The present invention is suitably usable, for example, for photoprinting a photomask pattern (reticle pattern) illuminated with slit-like light on a wafer while synchronously scanning the photomask and the wafer relative to the slit-like light and a projection optical system, for the manufacture of a semiconductor device such as an IC or LSI, an image pickup device such as a CCD, a display device such as a liquid crystal panel, or a device such as a magnetic head, for example.
The semiconductor device manufacturing technology has advanced remarkably, and the microprocessing technology has also advanced notably. Particularly, as regards reduction projection exposure apparatuses having a resolving power of submicron order, which play a major role in the optical processing technology, enlargement of a numerical aperture (NA) and shortening of exposure wavelength have been attempted, for further improvement of the resolution.
Also, changing a unit-magnification scanning exposure apparatus using a conventional reflection projection optical system has been proposed. That is, there is a scanning exposure apparatus which includes a reduction projection optical system comprising a combination of reflective and refractive optical elements (catadioptric system), or a reduction projection optical system comprising refractive elements only, wherein a mask stage for a photomask and a wafer stage for a photosensitive substrate are scanningly moved in synchronism with each other and at a speed ratio corresponding to the reduction magnification.
FIGS. 1 and 2 are schematic views, respectively, of a main portion of a scanning exposure apparatus which uses an exposure method according to a first embodiment of the present invention.
FIG. 3 is a flow chart for explaining the timing of a preparatory exposure in the exposure method according to the present invention.
FIGS. 4A-4D are schematic views, respectively, for explaining a preparatory exposure mark according to the present invention.
FIGS. 1 and 2 are schematic views, respectively, of a first embodiment wherein the exposure method of the present invention is applied to a scan type exposure apparatus. Specifically, FIG. 2 shows the irradiation range of exposure light in the scanning exposure apparatus. The structures of the optical systems in FIGS. 1 and 2 are exactly the same.
The first embodiment concerns a step-and-scan type exposure apparatus wherein light emitted from a light source 100 is projected through an illumination system (illumination optical system) 101 onto a reticle (mask) 102. In response thereto and by scanningly moving the reticle 102 and a wafer 108, a circuit pattern formed on the reticle 102 is projected in a reduced scale through a projection lens (projection optical system) PL and printed thereby on the wafer 108 having a photosensitive material applied thereto. Such a scanning exposure apparatus is suitably usable for the manufacture of semiconductor devices such as ICs or LSIs, image pickup devices such as CCDs, display devices such as liquid crystal panels, or devices such as magnetic heads, for example.
In FIGS. 1 and 2, an exposure light beam emitted from the light source 100, which may comprise a laser or an ultra-high pressure Hg lamp, is directed to the illumination system 101, by which the light is transformed into an illumination light beam having a predetermined numerical aperture, a predetermined illuminance, a predetermined light intensity and a predetermined uniformness and being effective to define a predetermined rectangular illumination region. The illumination light then illuminates a reticle (second object) 102.