Periodic and disordered polytypes of SiC: A dynamic model based on local deformations
Résumé
Silicon carbide exists under a great variety of polytypes that can be described by a sequence of orientations of diatomic Si-C layers in a stacking direction. A dynamical model is proposed for the formation of polytypes during the layer-by-layer growth of the material that occurs in CVD/CVI. A recurrence law is determined for the sequence of layer deformations ; the orientation sequence is derived from it. The evolution of this law allows one to reproduce qualitatively the whole polytypism of SiC: short- or long- period periodic polytypes, as well as one-dimensionally disordered polytypes. A two-parameter bifurcation diagram has been studied : its fractal structure allows one to visualize various types of ''roads to chaos".
Domaines
Matériaux
Origine : Fichiers produits par l'(les) auteur(s)