Indications are that very thin dielectrics needed for future generation of integrated circuits will be in a form of nitrogen-modified oxide. A significant amount of experimental data on growth kinetics for oxides grown/nitrided in N2O has been gathered. It appears that nitrogen neutralizes growth sites at the oxide-silicon interface, which significantly slows down the oxidation process when N2O is used as an oxidizing ambient. In this paper, the classic Deal-Grove formulation is extended to include the concentration of the growth sites. Also, the continuity equation applied to the growth sites is used to determine the concentration of the growth sites. This model has been incorporated into a TMA SUPREM-3 process simulator, and the model parameters calibrated with available experimental data. This provides not only the tool needed for process simulation, but also a better understanding of nitrogen modified oxide films.
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