Method of determining regularity of a pattern array to enable positioning of patterns thereof relative to a reference position

• US 5,153,678 A
• Filed: 08/30/1990
• Issued: 10/06/1992
• Est. Priority Date: 09/04/1989
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Ota, Kazuya
• Primary Examiner(s): Turner, Samuel A.
• Assistant Examiner(s): Kurtz, II, Richard E.
• Application Number:
  US07/575,426
• Time in Patent Office: 768 Days
• Field of Search: 356/401, 356/400, 356/399, 250/548, 250/557, 364/491
• US Class Current: 356/401
• CPC Class Codes: G03F 7/70425 Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning
• CPC Class Codes: G03F 7/70616 Monitoring the printed patterns
• CPC Class Codes: G03F 9/7003 Alignment type or strategy, e.g. leveling, global alignment
• CPC Class Codes: G03F 9/7049 Technique, e.g. interferometric

Abstract

A method of determining regularity of a pattern array on a substrate to enable sequential positioning of patterns of the array relative to a reference position includes the step of calculating a reliability degree regarding a measured value of a pattern position, and the step of determining the regularity of the pattern array on the basis of the calculated reliability degree, and a design value and the measured value of the pattern position.

Claims

1. A method of determining regularity of a pattern array on a substrate and of positioning patterns of the array relative to a reference position, comprising:

the step of calculating a reliability degree for a measured value of a pattern position;

the step of determining the regularity of the pattern array on the basis of the calculated reliability degree and a design value and the measured value of the pattern position; and

the step of sequentially positioning said patterns of the array relative to said reference position on the basis of the determined regularity.

2. A method according to claim 1, wherein

the measured value of the pattern position is detected as a position of an associated alignment mark with respect to the reference position, and

the reliability degree of the measured value is calculated on the basis of optical information generated by the alignment mark when a position of the alignment mark is optically detected.