Use of overlay diagnostics for enhanced automatic process control

US7310789B2 · kind B2 · utility

Assignee

• KLA-Tencor Technologies Corp. · US

Inventors

• Joel Seligson · Kiryat Shmona, IL
• Mark Ghinovker · Migdal HaEmek, IL
• John Robinson · Austin, US
• Pavel Izikson · Haifa, IL
• Michael Adel · Zichron Ya'akov, IL
• Boris Simkin · Haifa, IL
• David Tulipman · Or Akiva, IL
• Vladimir Levinski · Milpitas, US

Key dates

• Filing date: Aug 24, 2006
• Grant date: Dec 18, 2007
• Expiry date: Aug 24, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70633
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Disclosed are apparatus and methods for obtaining and analyzing various unique metrics or “target diagnostics” from one or more semiconductor overlay targets. In one embodiment, an overlay target is measured to obtain one or both of two specific types of target diagnostic information, systematic error metrics and/or random noise metrics. The systematic error metrics generally quantify asymmetries of the overlay target, while the random noise metrics quantify and/or qualify the spatial noise that is proximate to or associated with the overlay target.