Influence of hydrogen on (Ne + H 2 ) hollow cathode discharge characteristics

Abstract

The Hydrogen influence on (Ne+ H<SUB>2</SUB>) hollow cathode discharge plasma characteristics has been studied. The discharge voltage/current characteristics have been registered and the electron temperatures and concentrations have ben measured by using Langmuir's probe technique in both pure Ne and (Ne + H<SUB>2</SUB>) hollow cathode discharges as a function of H<SUB>2</SUB> concentration. The Hydrogen negative ion concentration has been obtained by the laser photodetachment method. The results show that small (up to 10%) concentrations of H<SUB>2</SUB> to Ne hollow cathode plasma improve the plasma conductivity and decrease the electron temperature. Negative hydrogen ions occur in (Ne + H<SUB>2</SUB>) hollow cathode discharge. Their density with (Ne + 10%H<SUB>2</SUB>) discharge is 2 X 10<SUP>8</SUP> cm<SUP>-3</SUP> and they should be taken into account for a description of the plasma studied.