Performances of Rh and Mo mirrors under JET exposure

• The aim of this work was to provide a comprehensive surface characterization of rhodium and molybdenum mirrors exposed on the main chamber wall of JET during campaigns with carbon plasma-facing components. As determined using X-ray photoelectron spectroscopy, Secondary Ion Mass Spectrometry, Scanning Electron Microscopy and optical measurements the co-deposits formed on the mirrors were composed of C, Be, Ni, Mo and Fe. Most of the metallic elements on the surface were in the oxidized states. After removing a part of the film by sputtering with Ar+ ions, Mo carbide state was studied by XPS. The reflectivity measurements showed the dependence of the thickness of the deposited film on the optical properties of the mirror: a thinner film on the Mo mirrors results in an identical reduction in reflectivity as that seen on the exposed Rh mirror.

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Nyckelord

Chamber walls

Deposited films

Metallic elements

Optical measurement

Oxidized state

Plasma-facing components

Reflectivity measurements

Surface characterization

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)