Factors Affecting VUV Emission Spectrum near Lyman-α from a Hydrogen Plasma Source

Abstract

Vacuum ultra violet (VUV) emission spectra from plasmas near walls of different metallic materials were measured to estimate the effect upon the local production rate of vibrational excited hydrogen molecules due to plasma wall interaction. Among Cu, Mo, Ni, Ta and Ti, the intensity of band spectrum around Lyman‐α had become the largest when Cu wall was used while it was the smallest for Ti. The role of particle reflection from the plasma electrode surface upon the H− production by a pure electron volume process is discussed.