Atomic force microscopy study of atomically flat (001) diamond surfaces treated with hydrogen plasma

An atomically flat (001) diamond surface has been obtained by hydrogen-plasma treatment. Atomic force microscopy shows that the diamond surface after the treatment consists of successive terraces with atomic steps runing parallel to the [110] direction. Step bunching with several atoms high sometimes takes place originating from the remaining polishing marks. The morphology is sensitive to the surface temperature during the treatment; the step bunching is not observed on the surfaces treated at higher temperatures (> 850°C). The experimental results indicate that the lateral propagation of the atomic steps takes place during the hydrogen-plasma treatments.