METROLOGY APPARATUS, LITHOGRAPHIC SYSTEM, AND METHOD OF MEASURING A STRUCTURE
First Claim
1. A metrology apparatus configured to measure a structure formed on a substrate to determine a parameter of interest, the metrology apparatus comprising:
- an optical system configured to focus radiation onto the structure and direct redirected radiation from the structure to a detection system, wherein;
the optical system is configured to apply a plurality of different offsets of an optical characteristic to radiation before and/or after redirection by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution; and
the detection system is configured to detect a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution, wherein each radiation intensity corresponds to a different one of the plurality of different offsets.
2 Assignments
0 Petitions
Accused Products
Abstract
A metrology apparatus is disclosed that has an optical system to focus radiation onto a structure and directs redirected radiation from the structure to a detection system. The optical system applies a plurality of different offsets of an optical characteristic to radiation before and/or after redirected by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution. The detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution. Each radiation intensity corresponds to a different one of the plurality of different offsets.
4 Citations
20 Claims
-
1. A metrology apparatus configured to measure a structure formed on a substrate to determine a parameter of interest, the metrology apparatus comprising:
-
an optical system configured to focus radiation onto the structure and direct redirected radiation from the structure to a detection system, wherein; the optical system is configured to apply a plurality of different offsets of an optical characteristic to radiation before and/or after redirection by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution; and the detection system is configured to detect a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution, wherein each radiation intensity corresponds to a different one of the plurality of different offsets. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method of measuring a structure formed on a substrate to determine a parameter of interest, the method comprising:
-
focusing radiation onto the structure and using a detection system to detect redirected radiation from the structure, wherein; a plurality of different offsets of an optical characteristic are applied to radiation before and/or after redirection by the structure, such that a corresponding plurality of different offsets are provided to redirected radiation derived from a first point of a pupil plane field distribution relative to redirected radiation derived from a second point of the pupil plane field distribution; and the detection system detects a corresponding plurality of radiation intensities resulting from interference between the redirected radiation derived from the first point of the pupil plane field distribution and the redirected radiation derived from the second point of the pupil plane field distribution, wherein each radiation intensity corresponds to a different one of the plurality of different offsets. - View Dependent Claims (16, 17, 18, 19, 20)
-
Specification