Measurements and interpretation of EEDF in a discharge with a hollow cathode in helium: effect of the measuring probe and the anode on the form of the distribution function

Experimental and theoretical studies of the electron energy distribution function in hollow cathode discharge plasma have been carried out. The discharge was ignited in helium at a pressure of 0.75 Torr, and the distance between the rectangular hollow cathode and anode was 3 cm. The measurements were performed using the probe method at various distances from the anode. The obtained distribution functions turned out to be strongly depleted in low-energy electrons. As applied to the experimental conditions, the role of two effects that can lead to such depletion was analyzed: instrumental distortions of the distribution function due to the electron sink on the probe and the absorption of electrons by the anode. According to the calculations, under the considered conditions, the main contribution to the depletion of the measured distribution functions by the slow electrons comes from the second effect.

Automated summary

Experimental and theoretical studies have been conducted on the electron energy distribution function in hollow cathode discharge plasma. It was found that under these conditions, low-energy electrons are significantly depleted, mainly due to electron absorption by the anode in close proximity.