Structure and morphology evolution of concave-shaped SiC {0001} surfaces in liquid silicon

TL;DR

This study investigates how the surface structure and morphology of concave 4H-SiC {0001} surfaces evolve in liquid silicon, revealing differences between Si and C faces related to symmetry, step bunching, and faceting.

Contribution

It provides detailed insights into the surface reconstruction and morphology evolution of SiC {0001} surfaces in liquid silicon, highlighting the effects of azimuthal and off-axis angles.

Findings

Si face shows six-fold symmetry and stronger step bunching along <1100>

C face exhibits more significant step bunching and less azimuthal sensitivity

Step faceting is more pronounced on the Si face and independent of off angle

Abstract

Concave-shaped 4H-SiC {0001} surfaces have been prepared and reconstructed in pure liquid silicon for investigating the structure and morphology evolution of the SiC surface as a function of both azimuthal and off-axis angles. Different surface characteristics are revealed on two polar surfaces where only the Si face reflects the six-fold symmetry of 4H-SiC crystal. On the Si face, the step bunching along the <1100> direction is stronger than the <1120> direction, which is related to the bonding state at the step edge. More significant step bunching is observed on the C face whereas it is not sensitive to azimuthal orientation. The extent of step faceting is stronger on the Si face. The step faceting is independent of the off angle on both polarities of SiC {0001} surfaces.