Survey of sampling techniques for solids suitable for microanalysis by total-reflection X-ray fluorescence spectrometry

Abstract

A survey of solid sampling techniques is given, suitable for microanalysis or even ultramicroanalysis by total-reflection X-ray fluorescence (TXRF). A sample amount of 1 ng to 100 µg is placed on a clean, flat carrier usually made of quartz glass or Plexiglas ® . For quantification, a drop is added to the sample with a known amount of a single element serving as internal standard. Solid samples can be applied as small particles, fine powders, thin sections or deposits. Several techniques of solid sampling have been examined and one example of each technique is given demonstrating its suitability: direct placing of individual particles, suspension of powdered materials, collection of air dust by impaction, the touchstone technique for metals, laser ablation for local analysis, the Q-tip technique for paints and inks, freeze-cutting of organic materials and direct contamination control of wafers.