Process tuning with polarization

摘要

A method for configuring an illumination source of a lithographic apparatus, the method including dividing the illumination source into pixel groups, each pixel group including one or more illumination source points in a pupil plane of the illumination source; changing a polarization state of each pixel group and determining an incremental effect on each of the plurality of critical dimensions resulting from the change of polarization state; calculating a first plurality of sensitivity coefficients for each of the plurality of critical dimensions using the determined incremental effects; selecting an initial illumination source; iteratively calculating a lithographic metric as a result of a change of polarization state using the calculated first plurality of sensitivity coefficients, the change of the polarization state of the pixel group in the initial illumination source creating a modified illumination source; and adjusting the initial illumination source based on the iterative results of calculations.

主权项

1. A method for configuring an illumination source of a lithographic apparatus to enhance the imaging of a mask pattern onto a substrate, the image of the mask pattern on the substrate having a plurality of critical dimensions, the method comprising:
dividing the illumination source into pixel groups, each pixel group including one or more illumination source points in a pupil plane of the illumination source; changing a polarization state of each pixel group and determining an incremental effect on each of the plurality of critical dimensions resulting from the change of polarization state of each pixel group; calculating a first plurality of sensitivity coefficients for each of the plurality of critical dimensions using the determined incremental effects; selecting an initial illumination source including a plurality of pixel groups; iteratively calculating a lithographic metric as a result of a change of polarization state of a single pixel group in the initial illumination source using the calculated first plurality of sensitivity coefficients, the lithographic metric in each iteration being calculated with the selected plurality of pixel groups in which the polarization state of the single pixel group has been changed and in which a polarized or unpolarized state of another pixel group of the selected plurality of pixel groups is unchanged, the change of the polarization state of the pixel group in the initial illumination source creating a modified illumination source; and adjusting the initial illumination source based on the iterative results of calculations.