Abstract:
A method of correcting an optical image formed by an optical system, the method including obtaining a map indicative of a polarization dependent property of the optical system across a pupil plane of the optical system for each spatial position in an image plane of the optical system, combining the map indicative of the polarization dependent property of the optical system with a radiation map of the intensity and polarization of an input radiation beam to form an image map, and using the image map to correct an optical image formed by directing the input radiation beam through the optical system.
Abstract:
Lithographic apparatus and device manufacturing methods are disclosed. In one arrangement there is provided an immersion lithographic apparatus comprising a projection system (PS). The projection system is configured to project a patterned radiation beam through an immersion liquid onto a target portion of a substrate. An external surface of the projection system comprises a first surface (102). The first surface has a non-planar shape. An element (106) is attached to the first surface and positioned so that at least a portion of the element contacts the immersion liquid in use. The element comprises a closed loop of continuously integral material in a preformed state and conforming to the non-planar shape of the first surface.
Abstract:
Described herein is a method for tuning a target apparatus of a patterning process. The method includes obtaining a reference performance, and measurement data of a substrate subjected to the patterning process at the target apparatus, the measurement data indicative of a performance of the target apparatus; determining a cause of a performance mismatch based on a difference between the reference performance and the performance of the target apparatus, wherein the cause includes an optical characteristic; and responsive to the cause, adjusting optical parameters associated with an adjustable optical characteristic to reduce the performance mismatch in the optical characteristic.
Abstract:
A method of modifying a lithographic apparatus comprising an illumination system for providing a radiation beam, a support structure for supporting a patterning device to impart the radiation beam with a pattern in its cross-section, a first lens for projecting the radiation beam at the patterning device with a first magnification, a substrate table for holding a substrate, and a first projection system for projecting the patterned radiation beam at a target portion of the substrate with a second magnification. The first lens and the first projection system together provide a third magnification. The method comprises reducing by a first factor the first magnification to provide a second lens for projecting the radiation beam with a fourth magnification; and increasing by the first factor the second magnification to provide a second projection system for projecting the patterned radiation beam at the target portion of the substrate with a fifth magnification.
Abstract:
A method for quantifying the effect of pupil function variations on a lithographic effect within a lithographic apparatus is disclosed. The method comprises: determining a discrete, two-dimensional sensitivity map in a pupil plane of the lithographic apparatus, wherein the lithographic effect is given by the inner product of said sensitivity map with a discrete, two-dimensional pupil function variation map of a radiation beam in the pupil plane. The pupil plane of a lithographic apparatus generally refers to the exit pupil of a projection system of the lithographic apparatus. Pupil function variations may comprise: relative phase variations within the pupil plane and/or relative intensity variations within the pupil plane.
Abstract:
An immersion lithographic apparatus comprising: a projection system for projecting a patterned radiation beam through an optically active part of a final lens element of the projection system towards a substrate supported by a substrate table, the final lens element having an exposed bottom surface; a liquid confinement structure configured to supply and confine immersion liquid to an immersion space between the final lens element of the projection system and a surface formed of at least one of the substrate and substrate table; and a passageway-former between the projection system and the liquid confinement structure, and a passageway between the passageway-former and the optically active part of the final lens element, the passageway being in liquid communication via an opening with the immersion space and extending radially outwardly with respect to an optical axis of the projection system at least to an edge of the exposed bottom surface of the final lens element and being constructed and configured such that in use it is filled with liquid from the immersion space by capillary action.
Abstract:
An immersion lithographic apparatus includes a projection system. The projection system is configured to project a patterned radiation beam through an immersion liquid onto a target portion of a substrate. An external surface of the projection system includes a first surface. The first surface has a non-planar shape. An element is attached to the first surface and positioned so that at least a portion of the element contacts the immersion liquid in use. The element includes a closed loop of continuously integral material in a preformed state and conforms to the non-planar shape of the first surface.
Abstract:
Described herein is a method for tuning a target apparatus of a patterning process. The method includes obtaining a reference performance, and measurement data of a substrate subjected to the patterning process at the target apparatus, the measurement data indicative of a performance of the target apparatus; determining a cause of a performance mismatch based on a difference between the reference performance and the performance of the target apparatus, wherein the cause includes an optical characteristic; and responsive to the cause, adjusting optical parameters associated with an adjustable optical characteristic to reduce the performance mismatch in the optical characteristic.