Method of setting up a projection exposure system, a projection exposure method and a projection exposure system for microlithography

A projection exposure method for exposing a radiation sensitive substrate with at least one image of a pattern comprising:

• generating illumination radiation directed onto the pattern in an illumination field;
• projecting a part of the pattern lying in the illumination field onto an image field at the substrate with projection radiation using a projection lens comprising a plurality of optical elements, wherein the image field exhibits mirror symmetry with respect to a line of mirror symmetry;
• measuring at least one property of the projection radiation representing an aberration level at a plurality of spaced apart measuring points distributed in the image field in accordance with a measuring point distribution defining a number and positions of measuring points used in a measurement using a measuring system, wherein the measuring point distribution is asymmetric with respect to the line of mirror symmetry;
• modifying imaging properties of the projection exposure system based on measurement results generated by the measuring system by an operating control system comprising at least one manipulator operatively connected to one of the optical elements of the projection exposure system, the method comprising:
• performing, in a first use case, a first exposure by illuminating a first pattern with illumination radiation according to a first illumination setting;
• reconfiguring the projection exposure system from a first configuration adapted to the first use case to a second configuration adapted to a second use case different from the first use case;
• performing, in a second use case, a second exposure by illuminating a second pattern with illumination radiation according to a second illumination setting;
• determining for each of the first use case and the second use case a corresponding first measuring point distribution and a second measuring point distribution;
• measuring the at least one property of the projection radiation separately for each of the first and second use case at measuring points distributed according to the first measuring point distribution and the second measuring point distribution, and
• modifying imaging properties of the projection exposure system separately for the first and the second use case based on measurements performed based on the first measuring point distribution and the second measuring point distribution.

A projection exposure method for exposing a radiation sensitive substrate with at least one image of a pattern comprising:

• generating illumination radiation directed onto the pattern in an illumination field;
• projecting a part of the pattern lying in the illumination field onto an image field at the substrate with projection radiation using a projection lens comprising a plurality of optical elements;
• measuring at least one property of the projection radiation representing an aberration level at a plurality of spaced apart measuring points distributed in the image field in accordance with a measuring point distribution defining a number and positions of measuring points used in a measurement using a measuring system;
• and
• modifying imaging properties of the projection exposure system based on measurement results generated by the measuring system by an operating control system comprising at least one manipulator operatively connected to one of the optical elements of the projection exposure system,
• wherein the image field exhibits mirror symmetry with respect to a line of mirror symmetry and the measuring point distribution is asymmetric with respect to the line of mirror symmetry.

A projection exposure system for exposing a radiation sensitive substrate with at least one image of a pattern, comprising:

• an illumination system configured to generate illumination radiation directed onto the pattern in an illumination field;
• a projection lens comprising a plurality of optical elements configured to project a part of the pattern lying in the illumination field onto an image field at the substrate with projection radiation, wherein the image field exhibits mirror symmetry with respect to a line of mirror symmetry,
• a measuring system configured to measure at least one property of the projection radiation representing an aberration level at a plurality of spaced apart measuring points distributed in the image field according to two or more different measuring point distributions, a measuring point distribution defining a number and positions of measuring points used in a measurement;
• an operating control system comprising at least one manipulator operatively connected to an optical element of the projection exposure system to modify imaging properties of the projection exposure system based on measurement results generated by the measuring system;
• a measuring point distribution determination system configured to determine a measuring point distribution defining a number and positions of measuring points used in a measurement, specific for a use case, wherein the measuring point distribution is asymmetric with respect to the line of mirror symmetry.