OPC model prediction capability improvements by accounting formask 3D-EMF effects

摘要

As mask feature sizes have shrunk well below the exposure wavelength, the thin mask of Kirchhoff approximationbreaks down and 3D mask effects contribute significantly to the through-focus CD behavior of specific features.While full-chip rigorous 3D mask modeling is not computationally feasible, approximate simulation methods doenable the 3D mask effects to be represented. The use of such approximations improves model prediction capability.This paper will look at a 28nm darkfield and brightfield layer datasets that were calibrated with a Kirchhoff modeland with two different 3D-EMF models. Both model calibration accuracy and verification fitness improvements arerealized with the use of 3D models.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.