Surface studies can support the physical understanding of the behaviour of superconducting material used in RF cavities. As most of the limitations occur in a very small portion of the surface, (typically less than the penetration depth of the material), only a few techniques can give valuable information. Some of these techniques will be discussed here, along with some examples of the results, showing the difficulty of interpretations. The used techniques are most commonly: XPS (X-ray Photoemission spectroscopy), SIMS, and TOF-SIMS (Time Of Flight Secondary Ions Mass Spectroscopy), EBSP (Electron BackScattering Patterns); some comments are also made about Auger, X-Ray reflectometry, GDL (Glow Discharge Luminescence), STM (Scanning Tunnelling Microscopy) and other common surface analyses. The influence of various surface treatments on grain boundary conduction is also explored. |
