Chloride‐based CVD of 3C‐SiC Epitaxial Layers on On‐axis 6H (0001) SiC Substrates

The growth of 3C‐SiC epitaxial layers on nominally on‐axis 6H‐SiC Si‐face substrates using the chloride‐based CVD process is demonstrated. A hot‐wall CVD reactor was used and HCl was added to the standard precursors (silane and ethylene). Several growth parameters were tested: temperature, in‐situ surface preparation, C/Si ratio, Cl/Si ratio, and nitrogen addition. Each parameter had a very important effect on the polytype formation. In the case of 3C‐SiC deposition the morphology and typology of defects could change significantly depending on the different combinations of growth conditions, including the addition of nitrogen. At a growth rate of 10 μm/h, a mirror‐like surface with a single domain decorated by some parallel stripes and few epitaxial defects were obtained. The near‐band gap luminescence of high quality 3C‐SiC layers was characterized by very sharp lines. Microscope and AFM analysis showed a very smooth surface. A background doping in the low $1015 cm−3$ range was achieved.