Abstract:
PROBLEM TO BE SOLVED: To provide a system and a method for determining the vibration modes relating to a lithographic apparatus and a measure of respective magnitudes thereof. SOLUTION: In the method, vibration-related information is determined by projecting an aerial image at an image position in a projection plane, by mapping the intensity of the aerial image into an image map wherein the image map includes values of coordinates of sampling locations and of the intensity sampled at the respective sampling locations, and by measuring the intensity of the aerial image received through a slot pattern. The method further comprises a step for determining the detection position of an inclined portion of the image map from the image map, a step for measuring the temporal intensity of the aerial image at the detection position of the inclined portion and measuring the relative position between the slot pattern and the image position, and a step for determining vibration-related information relating to the aerial image from the temporal intensity of the aerial image. COPYRIGHT: (C)2006,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide a system which cleans an object located on a limited area on the upper surface of a substrate table or the upper surface of the substrate table. SOLUTION: An optical system used in an usual imaging is adjusted to limit a sectional area of a radiation beam and form a cleaning radiation beam correspondent to the limited area. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a system and method for determining vibration modes and a measure for their respective magnitude for a lithographic apparatus. SOLUTION: The invention relates to a method for determining vibration-related information by projecting an aerial image at an image position in a projection plane, mapping an intensity of the aerial image into an image map, wherein the image map comprises values of coordinates of sampling locations and of the intensity sampled at each sampling location, and measuring intensity of the aerial image received through a slot pattern. The method further includes a step of determining, from the image map, a detection position of a slope portion of the image map, a step of measuring, at the detection position of the slope portion, a temporal intensity of the aerial image and measuring relative positions of the slot pattern and the image position, and a step of determining, from the temporal intensity of the aerial image, vibration-related information for the aerial image. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
Method of measuring a position of an obj ect by performing a first position measurement on the object (WT) by a first sensor (AS) while the object is stationary and a second position measurement on the object by a second sensor (IF) while the object is stationary. The first and second position measurement are differing from one another. Both the first position measurement and the second position measurement comprise taking a plurality of samples in time and presenting the first measurement and the second measurement, wherein the method comprises: generating an alignment beam, directing the alignment beam to an alignment mark (AM) positioned on the object, receiving a reflected beam from the alignment mark by said first sensor, and measuring the reflected beam from the alignment mark with the first sensor. The measured intensity varies with the position of the object. The intensity as measured by the first sensor which varies with the position of the object has at least one of: a low intensity having a slope of substantially zero as function of the position at a first position, a high intensity having a slope of substantially zero as function of the position at a second position, and an intensity which is in between the intensities of the first and second position having a slope different from zero at a third position, wherein the first, second and third positions are determined by an alignment scan prior to the first and second position measurements