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:
Nov. 18, 2025
Filed:
Feb. 16, 2022
Kla Corporation, Milpitas, CA (US);
Stilian Ivanov Pandev, Santa Clara, CA (US);
KLA Corporation, Milpitas, CA (US);
Abstract
Methods and systems for improved monitoring of tool drift and tool-to-tool matching across large fleets of measurement systems employed to measure semiconductor structures are presented herein. One or more Quality Control (QC) wafers are measured by each of a fleet of measurement systems. Values of system variables are extracted from the QC measurement data associated with each measurement system using a trained QC encoder. The extracted values of the system variables are employed to condition the corresponding measurement model employed by each measurement tool to characterize structures under measurement having unknown values of one or more parameters of interest. Accurate tool-to-tool matching across a fleet of conditioned measurement systems is achieved by extracting values of system variables from measurement data collected from the same set of QC wafers. Tool health is monitored based on changes in values of system variables extracted from measurements performed at different times.