CPC G01N 21/211 (2013.01) [G01N 2021/213 (2013.01); G01N 2201/126 (2013.01)] | 6 Claims |
1. A method for measuring a characteristic of a thin film formed on a substrate, the method comprising:
a) obtaining a measured spectrum (SE) from a target region on the substrate by using a spectroscopic ellipsometer,
b) obtaining a physical model (MP) capable of obtaining an estimated parameter value (PP) related to the characteristic of the thin film through a regression analysis of the measured spectrum (SE),
c) obtaining a machine learning model (MML) capable of obtaining a reference parameter value (PML) related to the characteristic of the thin film by using the measured spectrum (SE), and
d) obtaining an integrated model which uses an integrated error function (f) capable of considering both of a first error function (f1) between the measured spectrum (SE) and a calculated spectrum (SP) by the physical model (MP) and a second error function (f2) between the estimated parameter value (PP) input into the physical model (MP) in order to obtain the calculated spectrum (SP) and the reference parameter value (PML), and obtaining an optimum parameter value (PBEST) through a regression analysis of the integrated model.
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