Influence of electrode materials and surface roughness on the homogeneity of discharges in fluorine-based excimer laser gas mixtures

The influence of electrode materials and surface roughness on the discharge homogeneity of F₂ based excimer laser gas mixtures is investigated in a small x-ray preionised discharge chamber. The temporal and spatial evolution of the discharge is monitored by taking photographs of the discharge luminosity with an ICCD camera. It is found that for the same surface roughness, discharges with nickel coated aluminum electrodes are more homogeneous than the discharges using chromium or gold coated aluminum, massive copper, aluminum, brass and steel electrodes. Moreover, the surface roughness of copper electrodes does not have a large influence on the homogeneity of discharges in F₂ doped excimer laser gas discharges.