公开(公告)号：US20220316863A1

公开(公告)日：2022-10-06

申请号：US17705910

申请日：2022-03-28

Applicant: EBARA CORPORATION

Inventor： Nachiketa CHAUHAN ,  Keita YAGI ,  Akira NAKAMURA ,  Rohit KAWDE

IPC: G01B11/06

Abstract: A method of producing a model capable of reducing an influence of spectral variation of reflected light from a workpiece, such as a wafer, and capable of determining an accurate film thickness is disclosed. The method includes: determining sample features representing features of sample spectra of reflected lights from a sample having a film; obtaining similarities by calculating a similarity between each of the sample spectra and a representative spectrum; and producing a film-thickness estimation model by performing machine leaning using training data including the sample features, the similarities, and film thicknesses corresponding to the sample spectra.