Patent ID: 6604233
Filing Date: 2003-08-05
Classification: G03F

Abstract:
A method for determining an optimum shot map in a photolithographic process for a wafer surface, said method comprising the steps of:defining a set of input parameters; defining a circle with a diameter on said wafer surface; constructing a chip matrix comprising a plurality of chips, each of said plurality of chips having a plurality of corners, and whereby said plurality of chips are arranged in a regular pattern in a x-y Cartesian coordinate plane; generating a plurality of line segments formed by connecting said corners of any two chips in said plurality of chips such that each of said plurality of line segments has a length that is less than said diameter of said circle; defining a plurality of chip-to-wafer offsets of said chip matrix and said wafer surface whereby each of said chip-to-wafer offsets is defined by a chord formed by one of said plurality of line segments and said circle; determining a plurality of shot maps from said chip-to-wafer offsets and said set of input parameters; and determining an optimum shot map from said set of input parameters and said plurality of shot maps.