US 12,216,412 B2
Frequency-picked methodology for diffraction-based overlay measurement
Hung-Chih Hsieh, Miaoli County (TW); and Ming-Hsiao Weng, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on Nov. 22, 2023, as Appl. No. 18/517,653.
Application 18/517,653 is a continuation of application No. 17/132,871, filed on Dec. 23, 2020, granted, now 11,852,981.
Claims priority of provisional application 62/982,721, filed on Feb. 27, 2020.
Prior Publication US 2024/0085804 A1, Mar. 14, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. G03F 7/00 (2006.01); H01L 21/66 (2006.01)
CPC G03F 7/70633 (2013.01) [G03F 7/70625 (2013.01); H01L 22/12 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
disposing a first pattern over a substrate, the first pattern having a plurality of first sub-patterns extending in a first interval along a first direction and being arranged with a first pitch in a second direction crossing the first direction; and
disposing a second pattern over the substrate having a plurality of second sub-patterns disposed among the first sub-patterns and extending in a second interval along the first direction and being arranged with a second pitch different from the first pitch, in the second direction crossing the first direction;
disposing a third pattern over the first pattern, the third pattern having the first pitch and at least partially overlapping with the first pattern;
generating a first diffraction light associated with the first pitch at a first angle and a second diffraction light associated with the third pattern at the first angle;
generating a third diffraction light associated with the second pitch at a second angle, wherein the second angle is between 2 to 4 times larger than the first angle; and
determining an overlay error between the first pattern and the third pattern based on the first diffraction light and the second diffraction light.