Method and apparatus for correcting errors on a wafer processed by a photolithographic mask
AssigneeCarl Zeiss SMS GmbH
InventorsDirk Beyer, Vladimir Dmitriev, Ofir Sharoni, Nadav Wertsman
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Abstract
The invention relates to a method for correcting at least one error on wafers processed by at least one photolithographic mask, the method comprises: (a) measuring the at least one error on a wafer at a wafer processing site, and (b) modifying the at least one photolithographic mask by introducing at least one arrangement of local persistent modifications in the at least one photolithographic mask.
Claims19
A method for correcting at least one overlay error on wafers processed by at least one photolithographic mask, the method comprising:
- a. measuring the at least one overlay error on a wafer at a wafer processing site;
- b. modifying a global overlay error of the at least one overlay error of the at least one photolithographic mask by a linear transformation;
- and
- c. modifying a local overlay error of the at least one overlay error of the at least one photolithographic mask by introducing at least one arrangement of local persistent modifications in the at least one photolithographic mask.
An apparatus for correcting at least one overlay error on wafers processed by at least one photolithographic mask, comprising:
- a. at least one metrology system located in a wafer processing site and/or in a mask shop and adapted to measure the at least one overlay error on a wafer;
- b. at least one computing means adapted to calculate parameters for at least two error correcting means based on the at least one overlay error;
- c. at least one first error correcting means adapted for modifying a local overlay error of the at least one overlay error by introducing at least one arrangement of local persistent modifications in the photolithographic mask by applying ultra-short light pulse;
- and
- d. at least one second error correcting means adapted for modifying a global overlay error of the at least one overlay error by performing a linear transformation.
Dependencies are inferred from the claim text.