Abstract:
PROBLEM TO BE SOLVED: To provide tools for optimizing illumination sources and mask design layouts for use in lithographic apparatuses and processes.SOLUTION: Provided is a computer-implemented method for improving a lithographic process for imaging a portion of a design layout onto a substrate using a lithographic projection apparatus comprising an illumination source and projection optics, the method including: computing a multi-variable cost function of a plurality of design variables that are characteristics of the lithographic process, at least some of the design variables being characteristics of the illumination source and the design layout, the computation of the multi-variable cost function accounting for lens heating effects; and reconfiguring the characteristics of the lithographic process by adjusting the design variables until a predefined termination condition is satisfied.
Abstract:
A computer-implemented method for improving a lithographic process for imaging a portion of a design layout onto a substrate using a lithographic projection apparatus comprising an illumination source and projection optics, the method including computing a multi-variable cost function of a plurality of design variables that are characteristics of the lithographic process, at least some of the design variables being characteristics of the illumination source and the design layout, the computing of the multi-variable cost function accounting for lens heating effects; and reconfiguring the characteristics of the lithographic process by adjusting the design variables until a predefined termination condition is satisfied.