[14a-A410-1~10] 15.6 Group IV Compound Semiconductors (SiC)

[14a-A410-6] Step morphology on SiC surfaces clarified by first-principles calculations

〇Kaori Seino^1,2, Atsushi Oshiyama¹ (1.Nagoya Univ., 2.X-Ability)

Keywords:SiC, first-principles calculations, surface step

We have performed real-space density-functional calculations that reveal the causality between the energetics of the surface atomic steps and the morphology of the stepped surfaces on the SiC(0001) surface. We have done detailed structural optimization for possible mono-bilayer atomic steps on SiC surfaces and found the peculiar structural reconstruction near step edges. The calculated formation energies of the atomic steps reveal the origin of the experimentally observed variation of the step morphology, i.e., the emergence of either the straight or the meandering step edge, depending on the inclined direction of the vicinal SiC surfaces. We find that the reconstructions near the steps play decisive roles in the step energetics.