Study on negative ion production by electronegative gases in a helicon source

Abstract

A helicon plasma source (HeliPS) experimental set-up is developed to perform experiments in electronegative gases. Characterization of HeliPS is done in argon and oxygen discharge by varying the working pressure, magnetic field strength as well as radio frequency power at 13.56 MHz thereby identifying the optimum parameters for its operation. After characterization, experiments have been performed in electronegative gases such as oxygen and hydrogen to understand the effect of electron affinity in producing negative ions in such plasmas. To enhance the negative ion production, both magnetic filter and magnetic cage, used innovatively in such a system, shows interesting results on their influence in electronegative plasma production.