3-D topography and impurity integrated process simulator (3-D MIPS) and its applications

We have developed a practical 3-D integrated process simulator (3-D MIPS) b ased on the orthogonal grid. 3-D MIPS has a 3-D topography simulator (3-D M ULSS) and 3-D impurity simulator which simulates the processes of ion impla ntation, impurity diffusion and oxidation. In particular, its diffusion and segregation model is new and practical. It assumes the continuity of impur ity concentration at the material boundary in order to coordinate with the topography simulator (3-D MULSS) with cells in which two or more kinds of m aterials exist. And then, we introduced a time-step control method using th e Dufort-Frankel method of diffusion analysis for stable calculation, and a selective oxidation model tu al,ply to more general structures than LOGOS structure. After that, the 3-D MIPS diffusion model is evaluated compared w ith experimental data. Finally, the 3-D MIPS is applied to 3-D simulations of the nMOS Tr. structure with LOGOS isolation, wiring interconnect and pn- junction capacitances, and DRAM storage node area.