On the Nanostructure of SiC
|Periodical||Journal of Nano Research (Volume 12)|
|Main Theme||Journal of Nano Research Vol. 12|
|Citation||Maya Marinova et al., 2010, Journal of Nano Research, 12, 99|
|Online since||December, 2010|
|Authors||Maya Marinova, Efstathios K. Polychroniadis|
|Keywords||6H-SiC, Long Period Polytypes, Stacking Fault, TEM|
The present work deals with the structural properties of silicon carbide in nanoscale dimensions. The examined crystals were 6H-SiC grown by Liquid Phase Epitaxy. The study was concentrated on the stacking faults and any other differences from the “correct” stacking order of the Si-C bilayers for this polytype. Three main types of stacking faults were observed: (i) Cubic lamellae with thickness of four and two Si-C bilayers, always occurring in reverse stacking with respect to each other and separated by at least one unit cell of 6H-SiC; (ii) “twinned” 6H-SiC lamellae separated by a two-bilayer thick cubic inclusion. As a result the sequence in the “twinned” 6H-SiC changes from (3+3-) to (3-3+). (iii) Lamellae showing fringes, the interrelated distance of which suggests inclusion with sequence (22). Further, a high variety of sequences was found, leading to the appearance of rare 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.