A simple method to monitor the beam flux of neutral free radicals produced by photo-deionization of negative ion beams

Ion-current difference measurement by light intensity modulation (ICD) is introduced as a convenient method to determine the number flux of netural free radicals produced by photo-deionization of a negative ion beam for the purpose of surface-reaction-selective device processing. The ICD setup developed in this study exhibited the high precision and the high sensitivity under the experimental condition that the beam kinetic energy of the neutral free radicals was higher than 10 keV.