Nitrogen Atom Density Measurements in NAGDIS-T Using Vacuum Ultraviolet Absorption Spectroscopy

Abstract

For the development of a high nitrogen atom density source, we produced nitrogen plasmas and measured the nitrogen atom density using vacuum ultraviolet absorption spectroscopy (VUVAS) at high neutral gas pressure (>1.5 mTorr) and discharge power (>500 W) in the NAGDIS-T, which could generate spiral-shaped dissociative recombining plasmas. It was seen that the nitrogen atom density increases with increasing neutral gas pressure and discharge power, and it reached 6.2 × 10¹⁷ m⁻³. In the low gas pressure case, the estimated atom density was confirmed to be consistent with that measured by the actinometry method.