Generating an alignment signal without dedicated alignment structures

Abstract

Generating an alignment signal for alignment of features in a layer of a substrate as part of a semiconductor manufacturing process is described. The present systems and methods can be faster and/or generate more information than typical methods for generating alignment signals because they utilize one or more existing structures in a patterned semiconductor wafer instead of a dedicated alignment structure. A feature (not a dedicated alignment mark) of the patterned semiconductor wafer is continuously scanned, where the scanning includes: continuously irradiating the feature with radiation; and continuously detecting reflected radiation from the feature. The scanning is performed perpendicular to the feature, along one side of the feature, or along both sides of the feature.

Dependencies are inferred from the claim text.