The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 20, 2026
Filed:
Jun. 15, 2023
Kla Corporation, Milpitas, CA (US);
Ming Di, Milpitas, CA (US);
Qiang Zhao, Milpitas, CA (US);
Tianhao Zhang, Shanghai, CN;
Dawei Hu, Shanghai, CN;
Yih Chang, Shanghai, CN;
XI Chen, Shanghai, CN;
KLA Coporation, Milpitas, CA (US);
Abstract
Methods and systems for measuring values of one or more parameters of interest, including changes in values of one or more parameters of interest, based on measured spectral differences are presented herein. A trained spectral difference based measurement model determines changes in the values of one or more parameters of interest based on a measure of differences in spectra measured before and after one or more process steps. In some examples, a measure of spectral difference is determined based on a difference in measured intensity, a difference in harmonic signal values, or a difference in value of one or more Mueller Matrix elements. A measure of spectral difference may be expressed as a set of difference values, a scalar value, or coefficients of a functional fit to difference values. A measure of spectral difference may be determined based on a weighting of spectral differences according to wavelength.