Estimating and eliminating inter-cell process variation inaccuracy

US10415963B2 · kind B2 · utility

Assignee

• KLA-TENCOR CORPORATION · US

Inventors

• Tal Marciano · Haifa, IL
• Eran Amit · Haifa, IL
• Barak Bringoltz · Rehovot, IL
• Nuriel Amir · Yoqneam Illit, IL
• Amit Shaked · Nes Ziona, IL

Key dates

• Filing date: Jun 1, 2015
• Grant date: Sep 17, 2019
• Expiry date: Jun 1, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F30/398
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Metrology methods and targets are provided, for estimating inter-cell process variation by deriving, from overlay measurements of at least three target cells having different designed misalignments, a dependency of a measured inaccuracy on the designed misalignments (each designed misalignment is between at least two overlapping periodic structures in the respective target cell). Inaccuracies which are related to the designed misalignments are reduced, process variation sources are detected and targets and measurement algorithms are optimized according to the derived dependency.