Utilizing overlay misregistration error estimations in imaging overlay metrology

US10565697B2 · kind B2 · utility

Assignee

• KLA-TENCOR CORPORATION · US

Inventors

• Tzahi Grunzweig · Hillsboro, US
• Nadav Gutman · Zichron Ya'akov, IL
• David Gready · Tigard, US
• Mark Ghinovker · Migdal HaEmek, IL
• Vladimir Levinski · Milpitas, US
• Claire E. Staniunas · Forest Grove, US
• Nimrod Shuall · Beaverton, US
• Yuri Paskover · Or Akiva, IL

Key dates

• Filing date: Oct 22, 2017
• Grant date: Feb 18, 2020
• Expiry date: Feb 23, 2038

Classification

• Technology area (CPC G): Physics
• CPC primary: G06T2207/30148
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

Systems and methods are provided, which calculate overlay misregistration error estimations from analyzed measurements of each ROI (region of interest) in at least one metrology imaging target, and incorporate the calculated overlay misregistration error estimations in a corresponding estimation of overlay misregistration. Disclosed embodiments provide a graduated and weighted analysis of target quality which may be integrated in a continuous manner into the metrology measurement processes, and moreover evaluates target quality in terms of overlay misregistration, which forms a common basis for evaluation of errors from different sources, such as characteristics of production steps, measurement parameters and target characteristics. Such common basis then enables any of combining various error sources to give a single number associated with measurement fidelity, analyzing various errors at wafer, lot and process levels, and/or to trade-off the resulting accuracy for throughput by reducing the number of measurements, in a controlled manner.