Role of depth resolution in quantitative glow discharge optical emission spectrometry depth analysis

Abstract

The deterioration of depth profiles as observed in glow discharge optical emission spectrometry (GD-OES) is described by a numerical simulation in terms of crater shape and sputter-induced effects. Comparing measured intensity versus time curves with calculated profiles, information can be deduced which enables a better co-ordination between analytical signals and eroded depths, and thus improves the accuracy of quantitative GD-OES depth analysis. The practical depth resolution is satisfactory for the analysis of layers in the micrometre range. If layers with sub-µm thickness have to be analysed, crater curvature and surface roughness must be controlled carefully. Low argon gas pressure and constant operating voltage were found to be optimum working conditions.