Modeling stress retarded self-limiting oxidation of suspended silicon nanowires for the development of silicon nanowire-based nanodevices

In this paper, we present a model for the oxidation of silicon nanowires (NWs) based on a modification of the cylindrical Deal and Grove equation and taking into account stress effects associated with non-uniform deformation of the oxide by viscous flow. The validity of this model has been tested on a set of experimental results describing the thermal oxidation of suspended silicon NWs. The NWs oxidation is examined upon different atmospheres (pure O2 and H2O) and at different thermal budgets by scanning electron microscopy and transmission electron microscopy measurements. The good agreement between the experimental results and the simulations confirm the validity of the key model assumptions: the SiO2 flow can be approximated as purely viscous and the non-linear effects of shear stress on oxide viscosity [S. M. Hu, J. Appl. Phys. 64, 323 (1988)] can be neglected. In addition, the model gives some interesting insight about the physics of the oxidation process. In particular, we demonstrate that the compr...