US 12,135,504 B2
Method for determining best focus and best dose in exposure process
Kihyun Kim, Seongnam-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed on Nov. 17, 2021, as Appl. No. 17/528,637.
Claims priority of application No. 10-2021-0061322 (KR), filed on May 12, 2021.
Prior Publication US 2022/0365447 A1, Nov. 17, 2022
Int. Cl. G03F 7/00 (2006.01)
CPC G03F 7/70558 (2013.01) [G03F 7/70508 (2013.01); G03F 7/70625 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
selecting a selection pattern from first and second shot regions of a wafer for split;
measuring a critical dimension (CD) value of the selection pattern, thereby deriving a measurement CD value;
calculating an effective CD value of the selection pattern for each of the first and second shot regions using the measurement CD value;
calculating an upper-limit CD value and a lower-limit CD value of the selection pattern using the effective CD value of the selection pattern;
calculating a process window area for the first shot region and a process window area for the second shot region using the upper-limit CD value and the lower-limit CD value of the selection pattern; and
comparing the process window area for the first shot region and the process window area for the second shot region with each other.