Method of inspection, a method of manufacturing, an inspection apparatus, a substrate, a mask, a lithography apparatus and a lithographic cell

摘要

Each target used in a method of measuring overlay using a scatterometer includes a first portion and a second portion, the first portion has features varying only in a first direction and the second portion has features only varying in a second direction. The first and second directions are orthogonal, thus eliminating cross talk between the directions, and improving the accuracy of overlay error calculations.