An integrated circuit, a method and a system for designing and a method
fabricating the integrated circuit. The method including: (a) generating
a photomask level design of an integrated circuit design of the
integrated circuit, the photomask level design comprising a multiplicity
of integrated circuit element shapes; (b) designating regions of the
photomask level design between adjacent integrated circuit element
shapes, the designated regions large enough to require placement of fill
shapes between the adjacent integrated circuit elements based on fill
shape rules, the fill shapes not required for the operation of the
integrated circuit; and (c) placing one or more monitor structure shapes
of a monitor structure in at least one of the designated regions, the
monitor structure not required for the operation of the integrated
circuit.