Abstract: Prior to entering into manufacturing of a final production wafer, a series of test wafers are produced to analyze and test various structures. Each of the test wafers include a substrate, an insulating layer overlying the substrate, and a semi-conductive film layer formed over the insulating layer. The film layer is comprised of, for example, poly-silicon and has a predetermined thickness which substantially corresponds to the thickness of a film layer deposited on the final production wafer. The film layer is etched to form a desired pattern of structures and implanted with a dopant to diffuse dopant atoms thoughout. Thereafter, critical dimension measurements of the structures are taken preferably using electrical line width measurements techniques.

Abstract: A method of determining at least one of focus and coma of a lens at a selected location in an imaging field, includes the step of forming a predetermined pattern on a mask for transference to a wafer through a lens. The pattern including a plurality of features such that a first of the plurality of features is situated adjacent a first side of a first phase shift region formed on the mask, and a second of the plurality of features is situated adjacent a second side of a second phase shift region formed on the mask, the second side being substantially opposite the first side.