E-beam defect review system

US8094924B2 · kind B2 · utility

Assignee

• HERMES MICROVISION INC. · TW

Inventors

• Jack Jau · Los Altos Hills, US
• Zhongwei Chen · San Jose, US
• Yi Wang · Chicago, US
• Chung-Shih Pan · Palo Alto, US
• Joe Wang · Toronto, CA
• Xuedong Liu · San Jose, US
• Weiming Ren · San Jose, US
• Wei Fang · Milpitas, US

Key dates

• Filing date: Dec 15, 2008
• Grant date: Jan 10, 2012
• Expiry date: May 4, 2030

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J2237/2817
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An apparatus comprises an imaging unit to image a wafer to be reviewed, wherein imaging unit is the modified SORIL column. The modified SORIL column includes a focusing sub-system to do micro-focusing due to a wafer surface topology, wherein the focusing sub-system verifies the position of a grating image reflecting from the wafer surface to adjust the focus; and a surface charge control to regulate the charge accumulation due to electron irradiation during the review process, wherein the gaseous molecules are injected under a flood gun beam rather than under a primary beam. The modified SORIL column further includes a storage unit for storing wafer design database; and a host computer to manage defect locating, defect sampling, and defect classifying, wherein the host computer and storage unit are linked by high speed network.