Domain decomposition method for Maxwell's equations:: Scattering off periodic structures

We present a domain decomposition approach for the computation of the electromagnetic field within periodic structures. We use a Schwarz method with transparent boundary conditions at the interfaces of the domains. Transparent boundary conditions are approximated by the perfectly matched layer method (PML). An adaptive strategy to determine optimal PML parameters is developed. Thus we can treat Wood anomalies appearing in periodic structures. We focus on the application to typical EUV lithography line masks. Light propagation within the multilayer stack of the EUV mask is treated analytically. This results in a drastic reduction of the computational costs and allows for the simulation of next generation lithography masks on a standard personal computer. (C) 2007 Elsevier Inc. All rights reserved.