Application of the hybrid finite-difference time-domain method to modeling curved surfaces in three-dimensional lithography simulation

摘要

Abstract: The original hybrid-FDTD method developed by Wu andItoh is extended to handle lossy material with positiveor negative dielectric constants. Numerical results aregiven to compare the hybrid-FDTD method and standardFDTD. The result show that the hybrid-FDTD method ismuch more accurate than standard FDTD when the samemesh spacing is used in both methods. In the case oflossy materials with negative dielectric constants, thehybrid-FDTD method is found to be found to be much moreaccurate than standard FDTD even when a mesh spacingfour times finer is used in the latter method. Theseresults highlight the importance of modeling curvedsurfaces accurately in DUV lithography simulation usingthe hybrid-FDTD method. !10