Scatterometry target employing non-periodic defect features to enhance or optimize target sensitivity to a parameter of interest

摘要

Embodiments of the invention include a target having a lattice of many periodically spaced and uniformly configured metrology features arranged in an array pattern over a target region. The lattice includes at least one defect region in the lattice, the defect region includes at least one intentionally introduced defect metrology feature. The defect feature configured to enable increased sensitivity of the target to a selected parameter of interest. The invention further encompassing associated methods of implementing the target and evaluating the parameter of interest.