Abstract:
A pulse modifying unit is provided in the illumination system of the lithographic apparatus to reduce the degradation of the expensive lens elements by billions of the high intensity ultraviolet pulses from the laser is configured to receive an input pulse of radiation along a first optical axis and further configured to emit one or more corresponding output pulses of radiation along a second optical axis, including a divider disposed along the first optical axis and configured to divide the incoming pulse into a first and a second pulse portion, wherein the divider is further configured to direct the first pulse portion along the second optical axis. A first and a second mirror, each with a radius of curvature, are disposed facing each other with a predetermined separation, configured to receive the second pulse portion and to redirect the second portion along the second optical axis. The optical path of the second portion through the pulse modifier is longer than that of the first portion, and the separation is less than radius of curvature.
Abstract:
A lithographic apparatus includes an illumination system including a field faceted mirror including a plurality of field facets and configured to receive radiation from a radiation source and form a plurality of images of the radiation source on corresponding pupil facets of a pupil faceted mirror. Each of the field facets is configured to provide an illumination slit at a level of a patterning device. The illumination slits are summed together at the level of the patterning device to illuminate the patterning device. First blades are configured to block radiation from a radiation source and each first blade is selectively actuable to cover a portion of a selectable number of field facets. The field faceted mirror further comprises partial field facets, the partial field facets being configured to produce a partial illumination slit at the level of the patterning device, and the pupil faceted mirror further includes pupil facets corresponding to the partial field facets. The partial field facets are configured to produce an illumination slit that is summed with the summed illumination slits of the field facets and/or correct for non-uniformity in the summed illumination slits of the field facets. Second blades are selectively actuable to cover a portion of a selectable number of partial field facets.
Abstract:
A beam modifying device configured to receive an input radiation beam along a first optical axis, and configured to emit an output radiation beam along a second optical axis. The beam modifying device includes a divider disposed along the first optical axis and configured to divide the incoming radiation beam into a first part and a second part, the divider being configured to direct the first part along the second optical axis and to direct the second part via a delay path. The beam modifying device further includes optics forming the delay path, the optics being configured to receive the second part and to direct the second part via the delay path and then along the second optical axis. The optics are arranged to mirror the second part such that the second part is mirrored with respect to the first part.
Abstract:
An optical attenuator device operates to remove a part of a beam of radiation having a higher than average intensity using at least one optical attenuator element. The device has application in a radiation system, and/or a lithographic apparatus, in particular a scanning lithographic apparatus, wherein the optical attenuator element(s) are provided in a central part of the beam, for example perpendicularly to a scanning direction.
Abstract:
The invention relates to an illumination assembly, including a beam expander being arranged for receiving from a radiation source a radiation beam directed in a first direction (z) and for expanding the beam with a first magnification factor in a second direction (x) and with a second magnification factor in a third direction (y). The first, second and third directions being substantially mutually orthogonal. The illumination assembly further includes a beam splitter that is arranged for splitting the radiation beam in two split radiation beams split in at least one of the second and third direction, the propagation direction of the split radiation beams being substantially in the first direction. The beam splitter is further arranged for delivering the split radiation beams to the beam expander, of which at least one of the magnification factors is adjustable.
Abstract:
A lithographic apparatus comprises an illumination system for providing a projection beam of radiation. A support structure is provided for supporting a patterning device, the patterning device serving to impart the projection beam with a pattern in its cross-section. A substrate table holds a substrate, while a projection system projects the patterned beam onto a target portion of the substrate. The illumination system comprises a field defining element arranged to define an illuminating field in the plane of the patterning device or in a plane conjugate thereto, the field being off-axis with respect to the optical axis of the illuminating system.
Abstract:
The present invention provides a lithographic apparatus comprising an illumination system for providing a projection beam of radiation. The illumination system comprises at least one movable optical element (7), such that a projection beam of radiation (4) can be shifted around a central position. This ensures that inhomogeneities in the intensity distribution in the projection beam (4) will be smeared out, which in turn provides an improved homogeneity of the exposure of a surface to be illuminated by the system, such as a wafer or other substrate. The optical element (7) may comprise a motor movable mirror, prism, filter, lens, axicon, diffuser, diffractive optical array, optical integrator, etc. The invention further provides a device manufacturing method, using a lithographic apparatus according to the invention, wherein the optical element is moved, in order to provide an optimum homogeneity for the projection beam of radiation.