Influence of growth conditions on the structural perfection of β-SiC epitaxial layers fabricated on 6H-SiC substrates by vacuum sublimation

We report on the influence of the surface quality of substrate, growth rate and vapour phase composition in the growth cell on, both, the size of double position twins (and correspondingly the density of double position boundaries) in β-SiC epitaxial layers and on the perfection of interfacial layers in β-SiC/6H-SiC structures. The growth of β-SiC was done by vacuum sublimation on the (0001)Si-face of 6H-SiC Lely substrates. Epitaxial layers of β-SiC, with 5–6 mm2 double position twins and low (101–102 cm2) defect density, have been grown. The resulting β-SiC/6H-SiC heterostructures had no damaged intermediate layers at the interface.