Benchmark of FEM, Waveguide and FDTD Algorithms for Rigorous Mask   Simulation
  An extremely fast time-harmonic finite element solver developed for the transmission analysis of photonic crystals was applied to mask simulation problems. The applicability was proven by examining a set of typical problems and by a benchmarking against two established methods (FDTD and a differential method) and an analytical example. The new finite element approach was up to 100 times faster than the competing approaches for moderate target accuracies, and it was the only method which allowed to reach high target accuracies. 
S. Burger, R. K\"ohle, L. Zschiedrich, W. Gao, F. Schmidt, R. M\"arz,   C. N\"olscher