Abstract
A 13.56-MHz Grimm-style glow discharge plasma in which pulsated bias currents are introduced was investigated concerning the analytical applications. The d.c. bias currents driven by a self-bias potential are conducted through the r.f. plasma body by using a low-pass filter circuit and a variable resistor. Excitation by a modified r.f. plasma can yield larger emission intensities. By modulating the bias current associated with phase- sensitive detection, the emission intensities can be measured at very low noise levels, enabling the detection limit to be improved more. A detection limit of 3 x 10-4 mass % was obtained for Mn determination in Fe-based binary alloy samples, whereas 1.4 x 10-2 mass % Mn was obtained in the conventional excitation of an 80-W r.f. discharge plasma.
Original language | English |
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Pages (from-to) | 517-523 |
Number of pages | 7 |
Journal | analytical sciences |
Volume | 15 |
Issue number | 6 |
DOIs | |
Publication status | Published - 1999 Jun |
Keywords
- Conduction of the bias current
- Current modulation
- Detection limit
- Fe-based alloys
- Radio-frequency Grimm glow discharge plasma
- Self-bias potential
ASJC Scopus subject areas
- Analytical Chemistry