POWER, FLOW-RATE, AND PRESSURE EFFECTS IN A JET-ASSISTED GLOW-DISCHARGE SOURCE

Effects brought about by power and flow rate through the jets and pressure changes in a jet-assisted glow discharge source were studied. An increase in the power dissipated in the glow discharge increased both the sample sputtering and excitation of sputtered species in the negative glow. Although the application of the jets resulted in a similar increase in sample atomization, no uniform enhancement of emission intensities was observed. Instead, some emission lines were reduced in intensity, typically those characterized by relatively large absorption coefficients; while others were enhanced, those possessing relatively small absorption coefficients. This behaviour is suggestive of a self-absorption problem. Consequently, the most sensitive lines typically used for atomic emission analyses in glow discharges, resonance lines with large absorption coefficients, suffered from profound self-absorption with the application of the jets.