We provide a full set of growth rate coefficients to enable high-accuracy two-and three-dimensional simulations of dry thermal oxidation of 4H-silicon carbide. The available models are insufficient for the simulation of complex multi-dimensional structures, as they are unable to predict oxidation for arbitrary crystal directions because of the insufficient growth rate coefficients. By investigating timedependent dry thermal oxidation kinetics, we obtain temperature-dependent growth rate coefficients for surfaces with different crystal orientations. We fit experimental data using an empirical relation to obtain the oxidation growth rate parameters. Time-dependent oxide thicknesses at various temperatures are taken from published experimental findings. We discuss the oxidation rate parameters in terms of surface orientation and oxidation temperature. Additionally, we fit the obtained temperaturedependent growth rate coefficients using the Arrhenius equation to obtain activation energies and pre-exponential factors for the four crystal orientations. The thereby obtained parameters are essential for enabling high-accuracy simulations of dry thermal oxidation and can be directly used to augment multi-dimensional process simulations. Published by AIP Publishing.

We analyze the early stage of the highly anisotropic silicon carbide oxidation behavior with reactive force field molecular dynamics simulations. The oxidation of a-, C,- m-, and Si-crystallographic faces is studied at typical industry-focused temperatures in the range from 900 to 1200 °C based on the time evolution of the oxidation mechanism. The oxide thicknesses and the growth rates are obtained from these simulation results. In addition, an investigation of the silicon and carbon emission is performed with respect to various orientations in order to support further development of macroscopic physical models that aim to predict initial silicon carbide oxidation.

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We present numerical methods to enable accurate and robust level-set based simulation of anisotropic wet etching and non-planar epitaxy for semiconductor fabrication. These fabrication techniques are characterized by highly crystal orientation-dependent etch/growth rates, which lead to non-convex Hamiltonians in their description by the level-set equation. As a consequence, instable surface propagation may emerge, leading to unphysical results. We propose a calibration-free Stencil Lax-Friedrichs scheme and an advanced adaptive time-stepping approach, tailored to the level-set speed functions associated with anisotropic etching and epitaxy. The scheme calculates the numerical dissipation based on information about the local geometry and the nature of the etch rates/growth function, which enables an optimized tradeoff between overly rounding of sharp geometric features and stable surface propagation. Furthermore, we introduce the deposition top layer method, which allows for robust handling of multiple material regions in non-planar epitaxy simulations. Both methods are demonstrated in a prototypical implementation, which is used to validate the capability and accuracy of our approaches. In particular, two-dimensional wet etching and three-dimensional epitaxy simulations are performed and characteristic geometry parameters are compared to the ideally expected values, showing robustness and high accuracy.

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