Patent ID: 7450748
Filing Date: 2008-11-11
Classification: G03F

Abstract:
1. A mask inspection method, comprising: generating a mask fabrication database describing geometrical shapes S to be printed as part of a mask pattern on a reticle to fabricate a mask through use of a mask fabrication tooling, said geometrical shapes S appearing on the mask pattern as geometrical shapes S′ upon being printed by the mask fabrication tooling in accordance with the mask fabrication database, at least one of said geometrical shapes S′ being geometrically distorted relative to a corresponding at least one of said geometrical shapes S due to a lack of precision in the mask fabrication tooling; generating a mask inspection database to be used for inspecting the mask after the mask has been fabricated by the mask fabrication tooling using the mask fabrication database, said mask inspection database describing geometrical shapes S″ approximating said geometrical shapes S′, a geometric distortion between said geometrical shapes S′ and said geometrical shapes S″ being less than a corresponding geometric distortion between said geometrical shapes S′ and said geometrical shapes S; fabricating the mask via the mask fabrication tooling using the mask fabrication database; inspecting the fabricated mask using the mask inspection database; determining an inspection failure rate from said inspecting, said determined inspection failure rate being lower than an inspection failure rate that would have been determined by using the mask fabrication database for inspecting the fabricated mask; wherein said generating the mask inspection database comprises: wherein the geometrical shapes S includes a geometric shape S wherein the calibration transformation transforms S wherein a first dimension of S wherein a second dimension of S