Annealing induced defects in SiC, SiOx single layers, and SiC/SiOx hetero‐superlattices

SiC/SiOx hetero‐superlattices as well as single layers of SiC and SiOx were fabricated and annealed at various annealing temperatures to investigate the evolution of annealing induced defects in these materials. We show that in SiC and SiOx materials and in SiC/SiOx multilayer system, crystallization, atomic diffusion, structural reconstruction, and hydrogen effusion take place upon annealing with different characteristic temperature dependences. The dependence of the spin densities on annealing temperature is explained as an overlap of the temperature dependence of the creation of additional dangling bonds due to hydrogen effusion and of the healing of dangling bonds due to element motion during the structural reconstruction. The stronger increase of spin density upon annealing in SiC as compared to SiO1.2 is ascribed to the effusion of a higher amount of hydrogen and the less efficient atomic diffusion up to the annealing temperature of 1050 °C.

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