US 12,216,072 B2
Reticle thermal expansion calibration method capable of improving sub-recipe
Maohua Ren, Shamen (CN); Yuan-Chi Pai, Fujian (CN); and Wen Yi Tan, Fujian (CN)
Assigned to United Semiconductor (Xiamen) Co., Ltd., Fujian (CN)
Filed by United Semiconductor (Xiamen) Co., Ltd., Fujian (CN)
Filed on Aug. 22, 2021, as Appl. No. 17/408,481.
Claims priority of application No. 202110879709.3 (CN), filed on Aug. 2, 2021.
Prior Publication US 2023/0030500 A1, Feb. 2, 2023
Int. Cl. G01N 25/16 (2006.01); G01B 5/00 (2006.01); G03B 27/42 (2006.01)
CPC G01N 25/16 (2013.01) [G01B 5/0014 (2013.01); G03B 27/42 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A reticle thermal expansion calibration method comprising:
exposing, by a scanner, a first group of wafers using a reticle;
generating, by a computing system, a first sub-recipe based on temperature data collected during the exposure of the first group of wafers, wherein the first sub-recipe comprises exposure parameters for subsequent wafer exposures;
performing, by the computing system, data mining and data parsing on the collected temperature data to generate a plurality of overlay parameters for the first group of wafers;
extracting, by the computing system, a plurality of predetermined parameters from the plurality of overlay parameters for the first group of wafers, wherein the predetermined parameters are related to reticle thermal expansion compensation;
performing, by the computing system, a linear regression on each of the predetermined parameters; and
generating, by the computing system, a first coefficient of determination for each of the predetermined parameters;
calibrating, by the computing system, the reticle thermal expansion compensation based on the first coefficient of determination for each of the predetermined parameters; and
exposing, by the scanner, subsequent wafers using the calibrated reticle thermal expansion compensation.