Influence of Discharge Parameters on the Resultant Sputtered Crater Shapes for a Radio Frequency Glow Discharge Atomic Emission Source

Abstract

A parametric study has been conducted on a radio frequency glow discharge atomic emission spectrometry (rf-GD-AES) source to evaluate the sputtering characteristics and resultant crater shapes for both metallic and nonconducting samples. These studies include a determination of how the operating parameters, namely, power and pressure, influence the sputtered crater's depth, the degree of convexity and/or concavity, and the crater bottom roughness. The results imply that many similarities exist between the rf mode of powering and the well-characterized dc powered devices. Some differences are noted, namely, differing crater shapes at low operating pressures and a lesser dependence of crater flatness on the applied voltage, i.e., dc-bias voltage. A new method of quantifying the degree of concavity/convexity is introduced which involves comparison of the calculated (ideal) cross-sectional area to the resultant crater area as measured by a diamond stylus profilometer. The studies indicate that the rf-GD is well suited for depth-resolved analysis under correctly chosen operating conditions, which fortuitously correspond to those used for optimum bulk elemental analyses.

Practical Aspects in the Determination of Gaseous Elements by Radiofrequency Glow Discharge Atomic Emission Spectrometry

“…surface which: (1) reduces electrical conductivity and/or (2) has a lower sputter yield than pure aluminium. 24 Comparisons between the absorbance values for elements sputtered from the Nitrogen I Emission Intensities same samples sputtered with and without the addition of water vapor indicated that water also served to reduce free atom…”

“…Specifically, a Tencor P-10 (Mountain View, CA, USA) diamond stylus profilometer was employed to determine the In the present paper, a detailed analysis of the sources of gaseous element contamination in the operation of an rf-GD-average depth across the bottom of the sputter-eroded crater. 24 In this way, the respective sputtering rates for each experiment AES system is described. It is important to note that, unlike in GDMS experiments, cryogenic cooling of the GD volume could be compared under the same conditions of discharge power, pressure and analysis time.…”

“…The The external sample mount rf-GD source has been described in a previous study so only a brief description is given here. 24 gettering action of this device is based on the heating of the Zr powder to a temperature of 350-400 °C, which activates The source body (anode) is constructed of stainless steel with the dimensions of 8×6.5×6.5 cm. The flat sample is sealed the metal to adsorb molecular species in the supply gas stream.…”

On-line determination of sputtered depth in a radio frequency glow discharge atomic emission source by laser confocal displacement

“…Radio-frequency GD plasma conditions (power and pressure) and sample matrix greatly influence crater shape. 2 In the case where a very flat crater profile is obtained [ Fig. 5(b)], a single-point measurement method (anywhere along the crater bottom) would yield accurate results.…”

“…1 -4 Methods developed for depth-resolved analyses have been reported for a wide range of materials, including painted and oxide coatings, metals and glasses and superlattice materials. 2,3 Experience has illustrated that sputter rate (depth) determination remains the single most significant source of uncertainty in quantitative measurements.…”