Due to the complexity of modern production processes it is no longer sufficient to look at a single process step, since the individual steps have a strong influence on each other. The problem is that all the process simulation tools use their individual optimized data structures which are not compatible with each other. To solve this problem, the so-called Wafer State Server has been developed during the last three years at the Institute for Microelectronics. It holds the complete information describing the simulation domain in a volume mesh discretized format, and it provides convenient methods to access these data. The idea was that the simulators make use of these access methods to initialize their internal data structure, and that the simulators report their modifications of the wafer structure to the Wafer State Server.
During the last year several three-dimensional process simulation tools have been integrated into the Wafer State Server and new tools have been developed on the basis of the Wafer State Server. Among them are simulation tools which cover several semicondutor processing steps like deposition, etching, ion implantation, annealing, oxidation and masking steps.