The Ion Beam Etching (IBE) model is developed assuming the analogy between the evolution of hydrodynamic surfaces and that of vacuum-solid interfaces. The main physical phenomenon in the IBE is the ion sputtering where the transfer of ion energy to the surface allows to eject the surface atoms. The local etching rate is thus proportional to the energetic flux and to the sputtering yield. Mask erosion and shadowing are taken into account in the model. The angular dependence of the sputtering yield permits to underscore the faceting and trenching phenomena which respectively represent the formation of the facets in mask corners and the overetching in the trench sides. Besides, the effect of mask erosion on pattern transfer of both trench and mesa structures is studied. In comparison with the experimental profile, the simulated etching profile of the mesa, based on the IBE model, shows a good agreement.
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