Abstract: Techniques used to optimize the alignment performance of the CORE-2564PSM reticle writer are presented. In particular, unique procedures for accurately locating alignment marks with nonuniform background intensities are discussed. Site-by-site automatic illumination control is implemented to ensure optimal image intensity and contrast for the CCD-based image capture system. Process and metrology considerations that affect error measurement are discussed. The mean $PLU range/2 aligned overlay of the CORE-2564PSM is shown to be 35 - 55 nm. !6
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