For the most critical gate layers, the manual describes "Chromeless" designs where the quartz is etched to create 180° trenches with no chrome. Caution: This requires rigorous etch-depth control (etch depth = λ/(2*(n-1))). For quartz at 193nm, that is 172nm ± 1nm.
Because the High-NA lens uses a central obscuration (like a reflecting telescope), the manual introduces specific . Reticle designs must avoid placing critical features at the “shadow” of the obscuration. The manual provides a forbidden zone map for reticle coordinates relative to the field stop. asml reticle design manual
ASML systems rely on specific fiducial marks for reticle-to-wafer alignment and tool calibration. These must be included in the GDS-II or OASIS design file. For the most critical gate layers, the manual