Analysis of relaxation time for nitrogen-containing species to enter steps on misoriented (0001) surfaces during homoepitaxial growth of 4H-SiC

Abstract

Reported experimental results on homoepitaxially grown nitrogen-doped 4H-SiC on (038) and misoriented (0001) substrates under carbon-rich conditions in a SiH4–C3H8–N2–H2 system were analyzed according to surface diffusion theory dealing with step kinetics. On misoriented (0001) surfaces at 1723–1873 K, the relaxation time for a silicon adatom to enter a step was negligibly small. This finding, however, was not the case with the relaxation time for nitrogen-containing species (τ k N). The ratio of τ k N to the residence time of the nitrogen-containing species on the surfaces was estimated to be 0.1–0.2 at 1723–1823 K and 0.04 at 1873 K.