Variations of the emission Intensities of sputtered particles are Investigated when helium gas Is Introduced in argon (or neon) glow discharge plasmas. It Is clearly recognized that though the number of sample atoms In the plasma gradually decreases, the spectrum intensities emitted from neutral species Increase with the helium partial pressures mixed. In Ar–He mixture plasmas, the maximum Intensities are obtained at He/Ar pressure ratio = 1/1 or slightly more. A degree of the Intensity enhancement Is more marked as the emission line originates from the transition among energy levels having higher excitation energies. The addition of helium gas also provides a great Influence on the emission lines from singly Ionized Ions of sample. In Ar(Ne)-He mixture plasmas, a series of emission lines from singly Ionized Ions, which cannot be excited with pure argon (neon) plasmas, can be observed. This effect could be explained from the resonance colllsional energy transfer between helium Ions and sample atoms.
ASJC Scopus subject areas
- Analytical Chemistry