Liquid Phase Epitaxy of 4H-SiC Layers on On-Axis PVT Grown Substrates

Abstract

We performed liquid phase epitaxial growth of SiC layers on on-axis 4H-SiC substrates using Si solvent. It was found that the polytype controllability of the epilayer significantly depends on the growth process conditions. By optimizing them, polytype mixing in the epilayers can be completely suppressed. It is shown that the density of basal plane dislocations in the epilayers is much less than in the substrates due to on-axis growth. SIMS analysis showed that the concentrations of trace impurity elements (B,Al,Ti,V,Cr,Fe,Ni,P) in the epilayers are under lower detection limit. The only impurity is nitrogen resulting in an n-type layer. Carrier concentrations Nd-Na ranging from high 1016 to low 1017cm-3 are achievable.