Optical inspection method and apparatus

US5982921A · kind A · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• David Alumot · Rehovot, IL
• Gad Neumann · Rehovot, IL
• Rivka Sherman · Ramat HaSharon, IL
• Ehud Tirosh · Nes Ziona, IL

Key dates

• Filing date: Dec 3, 1997
• Grant date: Nov 9, 1999
• Expiry date: Dec 3, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/887
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and apparatus for inspecting the surface of articles, such as chips and wafers, for defects, includes a first phase of optically examining the complete surface of the article inspected at a relatively high speed and with a relatively low spatial resolution, and a second phase of optically examining with a relatively high spatial resolution only the suspected locations for the presence or absence of a defect therein.