The annealing behavior of amorphous SiC layers, which were produced by MeV Si-implantation of 6H-type samples, was investigated systematically by means of step-height measurements, X-ray diffraction and optical microscopy. Two annealing stages were found, and each of them caused a densification of the amorphous layer. At temperatures between 250 and 700C, the rapidity and the low activation energy (0.184eV) of the densification suggested that defect annealing processes were responsible for it. Partial crystallization and changes in the amorphous network structure were excluded as possible reasons for low-temperature densification. Annealing at temperatures above 700C was characterized by a combination of defect annealing and recrystallization. The crystallization kinetics were analyzed in terms of the Johnson-Mehl-Avrami theory. It was shown that the crystallization mode changed, with increasing temperature, from nucleated growth at 800C to epitaxial growth at 1000C. Recrystallization generated stresses in the layer, and could lead to surface cracking if the layer thickness exceeded a critical value.

Annealing and Recrystallization of Amorphous Silicon Carbide Produced by Ion Implantation. A.Höfgen, V.Heera, F.Eichhorn, W.Skorupa: Journal of Applied Physics, 1998, 84[9], 4769-74