The LOCOS structure shown in Fig. 6.3 is in principle a two-dimensional structure with a 0.4m stripped mask. Therefore, the three-dimensional simulation results from FEDOS can be compared with a two-dimensional oxidation simulation. For the stress dependent simulation with FEDOS a wet oxidation with a period of 20 minutes at 1000C was assumed. The same parameters are used for an oxidation simulation on an equivalent two-dimensional structure with the commercial process simulation program DIOS . The DIOS output is shown in Fig. 6.15. As illustrated in Fig. 6.10 the results from FEDOS are in good agreement with DIOS.