Patent ID: 9645079
Date: 2017-05-09
CPC Classifications: G01B,G01N,G03F

Claim:
1. An apparatus, comprising: an illumination source; a spatial light modulator (SLM); a beam splitter configured to direct a portion of light emanating from the illumination source along an illumination path to a surface of the spatial light modulator (SLM); an aperture stop disposed substantially at a pupil plane of the illumination path, the aperture stop having an aperture configured to transmit at least a portion of light directed from the surface of the SLM to a surface of one or more specimens; and a metrology tool configured to measure one or more characteristics of one or more metrology target structures of the one or more specimens, the metrology tool comprising: an entrance pupil configured to receive illumination directed from the surface of the SLM and transmitted through the aperture of the aperture stop; a beam splitter configured to receive illumination received through the entrance pupil of the metrology tool, the beam splitter further configured to direct at least a portion of the illumination passed through the entrance pupil to the one or more samples; an objective lens configured to focus the at least a portion of the illumination onto one or more target structures of the one or more samples; and a detector configured to collect a portion of illumination scattered from the one or more target structures of the one or more samples, wherein the SLM is configured to control an illumination pupil function of the illumination transmitted through the aperture, the illumination pupil function controlled by controlling a profile of illumination impinging on the surface of the SLM from the illumination source.