▎ 摘　　要

Damaged layers and polishing haze exist on substrate surfaces owing to abrasion during figuring processes, which deteriorate surface integrity. We have developed a novel damage-free ultraprecision figuring technique and obtained atomically flat and damage-free SiC(0001) surfaces with a domain size of 300-500 nm. Using ultraprecision-figured 0 degrees-off 4H-SiC(0001) surfaces as substrates, we demonstrated the formation of graphene layers upon them and successfully produced atomically flat monolayer graphene with a domain size of over 300 nm on entire ultraprecision-figured SiC surfaces by annealing in ultra high vacuum without any Si flux. The quality of the graphene layers on the ultraprecision-figured SiC surfaces was markedly higher than that of layers on non-figured SiC surfaces. This indicates that the damaged surface layers with scratches, defects, and so on, enhance roughness on SiC surfaces, and reduce the quality of graphene films. In addition, we found a new phenomenon:step terraces of 500 nm width exhibited erosion at step edges, leading to the creation of hexagonal pits at terraces, while step terraces of 300 nm width exhibited hardly any erosion. A graphitization mechanism was discussed. (C) 2011 Elsevier B.V. All rights reserved.