A voltage modulation technique was applied to the high sensitivity measurement In atomic emission spectrometry using a glow discharge source. The emission from the glow discharge plasma can be modulated by a cyclic variation In Input power to effect discrimination against the predominant noise sources on the discharge. Compared to a dc detection method, the signal-to-noise ratio was Improved by a factor of 20-50. It was found that the relative Intensities of the emission lines from sputtered elements were enhanced with the voltage modulation method. This Indicates that the sputtering process is greatly affected by the modulation.
ASJC Scopus subject areas
- Analytical Chemistry