Observation of stacking faults formed during homoepitaxial growthof p -type 4 H -SiC

Threading dislocations and their transformation into stacking faults (SFs) are observed in p -type 4 H -SiC epitaxial layers by high voltage transmission electron microscope. Homoepitaxial growth and in situ aluminum doping of 4 H -SiC epitaxial layers are carried out using the organosilicon precursor bistrimethylsilylmethane ( C 7 H 20 Si 2 and the metal-organic precursor trimethylaluminum ( C 3 H 9 Al ), and the free hole concentration of the most heavily aluminum-doped epitaxial layers is > 10 21 cm − 3 . Threading dislocations are formed at the interface between the epitaxial layer and the substrate. However, the density of these threading dislocations decreases toward the epitaxial layer surface with their transformations to SFs.