Characteristics of a hollow-cathode discharge containing negative ions

Abstract

Characteristics of the hollow-cathode discharge containing negative ions have been investigated focusing on a discharge in oxygen. Discharges with other gases which do not generate negative ions were measured for comparison. The electron energy distribution f(E) was measured by using the probe technique and the negative ion density by the laser photodetachment technique. Radial variations in the negative ion density, the discharge pattern and optical emissions were measured. The form of f(E) has a depletion in the low-energy part, suggesting that the effect of dissociative attachment occurs to generate negative ions.