Simulation of critical IC fabrication processes using advanced physical and numerical methods

Critical steps of IC fabrication are simulated by one- and two-dimensional computer programs using advanced physical models. Our codes deal with an arbitrary number of physical quantities such as concentrations of dopants, vacancies, interstitials and clusters, the electrostatic potential, and so on. Furthermore, they easily permit the exchange or variation of the physical models under consideration. As typical applications phenomena of coupled diffusion in one and two dimensions and dynamic arsenic clustering are investigated. The differences caused by the models of the zero space-charge approximation and the solution of the exact Poisson equation are studied by examples of As-B diffusion with various doping concentrations at different temperatures. A dynamic cluster model developed for the simulation of thermally annealed As implantations is compared to measured data of laser annealing experiments. A short outline of the mathematical and the numerical problems is given to show the amount of sophistication necessary for up-to-date process simulation.