Effect of the inside profile of a hollow cathode on the plasma plume

The effect of the inside profile of a hollow cathode on the intensity of plasma plume has been studied in a low-pressure ( approximately 3-torr) argon discharge. The effectiveness of three different 'inside' profiles of a hollow cathode was compared by performing emission spectroscopy on the plasma plume in each case. A conical-profile hollow cathode produced a plasma plume that was much more intense than the one in a commonly used cylindrical-profile hollow cathode.<
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