Patent · US Active

Method and system for EUV mask blank buried defect analysis

US10055833B2 · kind B2 · utility

1Cited by

5References

24Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Jan Hendrik Peters · Wuppertal, DE
Frederik Blumrich · Jena, DE
Anthony Garetto · Jena, DE
Thomas Scherübl · Berlin, DE
Renzo Capelli · Heidenheim, DE

Key dates

Filing date	Nov 25, 2015
Grant date	Aug 21, 2018
Priority date	—
Expiry date	Feb 17, 2036

Classification

Technology area (CPC G)Physics
CPC primaryG03F1/84
WIPO fieldComputer technology
WIPO sectorElectrical engineering

Abstract

A reflective mask inspection system comprises a short wavelength radiation source for irradiating a reflective mask. A detector system detects the short wavelength radiation reflected from the reflective mask and a controller compares reflectance images of the reflective mask from the detector to characterize the mask. The system analyzes the spatially resolved reflectance characteristics of the substrate from different angles with respect to normal to the substrate and/or at different angles of rotation of the substrate. This information can be used to then analyze the mask for buried defects and then characterize those defects. This technique improves over current systems that rely on atomic force microscopes, which can only provide surface information.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.