Source optimization for image fidelity and throughput

A computer-readable medium storing a sequence of instructions that when executed by a computer causes the computer to perform a method, the instructions comprising:

• instructions for receiving all or a portion of a layout database from which a target pattern of features to be created via a photolithographic process is selected;
• instructions for generating first corrected features of the layout database with a resolution enhancement technique to reduce imaging errors between the target pattern of features and an image produced on a wafer using the first corrected features;
• and
• instructions for selecting first pixel intensity values to be produced by an optical element when illuminated with light from an illumination light source, wherein the first pixel intensity values are selected to reduce imaging errors between the target pattern of features and the image produced on the wafer using the first pixel intensity values.

A computer-readable medium storing a sequence of instructions that when executed by a computer causes the computer to perform a method, the instructions comprising:

• instructions for receiving a description of a pixilated light source, the description defining properties of the pixilated light source when the pixilated light source is used in a photolithographic process;
• instructions for receiving a layout pattern defining a desired pattern of features to be produced on a wafer using the photolithographic process;
• instructions for generating a desired light source distribution for the pixilated light source, the generating comprising simulating the pixilated light source using means for evaluating image fidelity of an image approximating the desired pattern of features produced on a wafer using the pixilated light source;
• and
• instructions for generating a corrected layout pattern, the corrected layout pattern calculated to produce an image on a wafer that approximates the desired pattern of features.

A computer-implemented method, comprising:

• by a computer:
• selecting a pattern of features in a layout database to be created on a wafer by determining a symmetrical pattern of layout features in the layout database;
• defining a mathematical relationship between one or more pixel intensities produced by a diffractive optical element and the selected pattern of features;
• and
• assigning pixel intensities for the diffractive optical element using the mathematical relationship in one or more computer simulations, wherein:
• runtime for the computer simulations is reduced by simulating a portion, but not all, of the symmetrical pattern of layout features, and
• the pixel intensities are calculated to produce an image of the selected pattern of features on the wafer with greater image fidelity than other features in the layout database.