Patent ID: 7538344

Claim:
A test wafer comprising: a plurality of test regions; and a plurality of test structures within each of said plurality of test regions, each of said plurality of test structures having a different alignment between a first feature and a second feature within each of said test structures, said first feature and said second feature each in contact with at least one test pad, wherein a total number of test pads within each of said plurality of said test regions is equal to: a first number of test structures formed by a first photolithography condition multiplied by a first number of test pads required to measure each of said first number of test structures formed by said first photolithography condition; and one or more other test structures formed by one or more other photolithography conditions multiplied by one or more other number of test pads required to measure each of said one or more other test structures formed by said one or more other photolithography conditions, wherein said first photolithography condition comprises a first alignment between said first and second feature, and said one or more other photolithography conditions comprises another alignment between said first and second feature.