Patent ID: 8464193

Claim:
A method of performing optical proximity correction on a design layout, said method comprising: a first step of generating at least one design clip from said design layout, wherein each of said at least one design clip includes a subset of said design layout; a second step of assigning at least one measurement site to each of said at least one design clip; a third step of determining, for each selected design clip among said at least one design clip, whether said selected design clip satisfies a predetermined criterion for classifying said selected design clip as including at least one complex design feature, wherein said predetermined criterion includes one or a logical combination of whether said selected design clip has a perimeter to area ratio that is greater than a redefined critical perimeter to area ratio, and whether said selected design clip includes a measurement site at which an areal image slope is less than a predefined critical areal image slope, said areal image slope being a magnitude of a two-dimensional gradient of areal image intensity that is measured for a simulated intensity distribution that corresponds to said selected design clip; a fourth step of marking, for each selected design clip that is identified as satisfying said predetermined criterion, a region that satisfies said predetermined criterion with a marker layer; and a fifth step of performing OPC on regions not marked with said marker layer with an OPC program and performing OPC on regions marked with said marker layer with at least another OPC program different from said OPC program, wherein at least one of said second, third, fourth, and fifth steps is performed employing a system configured for performing optical proximity correction on design layouts, said system comprising a computing means and a non-transitory machine-readable data storage medium, wherein said computing means comprises a processor and a memory that are configured to run an automated program comprising said at least one of said second, third, fourth, and fifth steps.