Structure of C Deposition Layers Under Various Deposition Conditions

The structure of deposited carbon layers formed under various conditions ranging from small scale laboratory to large scale magnetic confinement devices was characterized using Raman spectroscopy. By comparing ion beam and TEXTOR experiments, the deposition temperature is found to be the dominant factor in three dimensional disorder of sp2 sites and sp3 ratio at T>493 K. While, no clear temperature dependence on properties of aromatic rings was observed, indicating other parameters responsible for the aromatic rings present in carbon deposition layers. The carbon layers from JET differed significantly, indicating influence of Be compound formation on Raman parameters.