Method and calibration mask for calibrating a position measuring apparatus
AssigneeCarl Zeiss SMS GmbH
InventorsNorbert Kerwien, Jochen Hetzler
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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.
Claims33
A calibration mask for calibrating an apparatus for the position measurement of measurement structures on a lithography mask, wherein the calibration mask comprises diffractive structures configured for the interferometric position measurement of the diffractive structures.
A use of a calibration mask comprising diffractive structures arranged thereon for the calibration of an apparatus for the position measurement of measurement structures on a lithography mask, wherein the diffractive structures are configured for the interferometric position measurement of the diffractive structures.
A method for calibrating an apparatus for the position measurement of measurement structures on a lithography mask, comprising 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.
A method for measuring a mask for microlithography, comprising the following steps:
- providing the mask having diffractive structures arranged thereon, and
- determining the positions of the diffractive structures with respect to one another by means of interferometric measurement.
Dependencies are inferred from the claim text.