Patent ID: 9080971
Filing Date: 2015-07-14
Classification: G01B,G01N,G03F

Abstract:
1. A metrology system, comprising: a light source configured to produce a diffraction-limited light beam; an apodizer configured to shape the light beam in an entrance pupil of illumination optics; a micromirror array device configured to direct the light beam from the light source to only certain portions of the entrance pupil; optical elements configured to direct the diffraction-limited light beam from the apodizer to a spot on a wafer and to collect scattered light from the spot; a field stop configured to reject a portion of the collected scattered light; a detector configured to detect scattered light that passes through the field stop and to generate output responsive to the detected scattered light such that the wafer is measured by the metrology system using scatterometry; and a computer system configured to determine a characteristic of the wafer using the output.