On the Polytypic Transformations in SiC

Abstract

In the present work we report on the polytypic transformations taking place in nanoscale dimensions within 6H-SiC crystals. The examined crystals were grown by Liquid Phase Epitaxy using a mixture of Si and Al as solvents. The study concentrated on the differences from the “correct” stacking order of the Si-C bilayers for 6H-SiC leading to the formation of other polytypes. A great variety of sequences was found, which resulted to the appearance of rare short and long period polytypes or individual lamellae having their “own” stacking inside the 6H-SiC matrix. These nanostructured faults which deteriorate the quality of the grown material indicate also their “sensitivity” to any small or even infinitesimal change of the growth conditions, due to the very small energy among them.