An improved analytical performance of magnetically boosted radiofrequency glow discharge

Direct current glow discharge mass spectrometric analysis of non-conducting materials using a surface coating method

“…One method is to use radio frequency (rf) glow discharge coupled with GD-MS. As rf-GD-MS can be directly used for the analysis of non-conducting materials including block, plate samples or pressed powdered samples without exposing any auxiliary conductors to the discharge, it has become one of the important research topics. [17][18][19][20][21][22][23][24] For instance, Bayón et al had used rf-GD-MS coupled with gas chromatography to determine selenoamino acids in biological samples, 21 Muñiz et al had used the pulsed-rf-GD-TOF-MS to analyze the bulk and thin coated glasses directly, 22 and Pisonero et al had used pulsed-RF-GD-TOF-MS for minor element determination and evaluation of diffusion/segregation effects on ultra-thin layers. 23 A second method was dc-GD-MS analysis using a secondary cathode.…”

Signal Enhancement with Stacked Magnets for High-Resolution Radio Frequency Glow Discharge Mass Spectrometry

“…17,18,22 Here, we demonstrate the effects of the magnetic field strength under different experiment conditions, namely, the discharge pressure and the rfpower.…”

“…16−18,21−23 For instance, Vega et al introduced a permanent block magnet into the rf-GD chamber coupled with an optical emission spectroscopy. 17 Similarly, Saprykin et al used a ring-shaped magnet behind the sample to improve the sensitivity of the rf-GD-MS. 21 The added external magnetic field could modify the motion of the electrons and cations into spiral trajectory under the Lorentz forces, leading to an increased ion bombardment probability and resulting in higher sputtering rates and signal intensities. 16,24,25 Such enhancement can be significantly affected by the magnetic field strength and its spatial distribution.…”

“…10,16 For a mass spectrometry, the sputtering rate and ionization efficiency play important roles in achieving the optimum analytical performance, 16 which could also be influenced by other factors such as gas pressure, rf-power, sample thickness, lattice binding energy of sample and so on. 17,18 With radio frequency (rf) discharges, nonconducting materials can be analyzed directly. However, the generator power is usually coupled capacitive to the plasma, so that the plasma power decreases with increasing thickness, thus sputtering rates, sensitivities and signal intensity decrease at the same time.…”

Larmor Precession: Observation and Utilization for Boosting the Signal Intensity of Radio Frequency Glow Discharge Mass Spectrometry

“…[8][9][10][11][12] Although GD-MS has been widely used in advanced materials, geology, environmental science, and other fields, it usually requires conducting material to support the discharge of the insulators because of poor sample conductivity. [13][14][15][16][17][18] The introduction of a radio-frequency (rf) source into GD-MS allows direct analysis of conductive and non-conductive samples, either bulk solids or layered materials. In addition, the development of a pulsed-rf-GD source has improved the analytical capabilities of rf-GD techniques.…”