Patent · US Active

Method and calibration mask for calibrating a position measuring apparatus

US8617774B2 · kind B2 · utility

3Cited by

8References

33Claims

0Family size

Assignee

Carl Zeiss SMS Ltd. · IL

Inventors

Norbert Kerwien · Mögglingen, DE
Jochen Hetzler · Aalen, DE

Key dates

Filing date	Apr 10, 2010
Grant date	Dec 31, 2013
Priority date	—
Expiry date	Jun 22, 2030

Classification

Technology area (CPC G)Physics
CPC primaryG03F9/7011
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A method for calibrating an apparatus for the position measurement of measurement structures on a lithography mask comprises the following steps: qualifying a calibration mask comprising diffractive structures arranged thereon by determining positions of the diffractive structures with respect to one another by means of interferometric measurement, determining positions of measurement structures arranged on the calibration mask with respect to one another by means of the apparatus, and calibrating the apparatus by means of the positions determined for the measurement structures and also the positions determined for the diffractive structures.

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