Validation of vapor phase decomposition–droplet collection–total reflection X-ray fluorescence spectrometry for metallic contamination analysis of silicon wafers

Picoliter solution deposition for total reflection X-ray fluorescence analysis of semiconductor samples

“…Previous experiments with 20 nL droplet size showed a linearity of TXRF signal response up to 20 ng total Ni in the array [20], which was an improvement in the linearity range over previously reported dried residues measured by TXRF [10,11]. The linearity range of the picoliter droplet arrays was studied by jetting a pattern of 88 × 87 depositions of 9 pL droplets, for a total of 7656 droplets in each array.…”

“…This level of automation, while possible with VPD-ICP-MS, is more difficult to achieve and thus it is usually regarded as a laboratory analysis. Even though automated VPD-TXRF systems are widely accepted in the semiconductor industry [7][8][9] there are areas for improvement such as expanding the linear dynamic range and controlling the morphology of the dried residue as that impacts the analytical signal [10][11][12][13][14][15][16][17]. The morphology has critical influence on effects like absorption of the fluorescence photons of the primary beam and therefore on the accuracy of the analysis.…”

A Procedure for the Improvement in the Determination of a TXRF Spectrometer Sensitivity Curve

“…Other inter-comparison studies have focused on the combination of VPD-DC with TXRF, more specifically on the accuracy of TXRF in the analysis of the micro-droplet residues. In comparison with independent techniques such as ICPMS and GFAAS, [14][15][16] these studies have reported the tendency of TXRF to underestimate the metallic concentration. Such of studies can be avoided with the appropriate selection of the samples studied.…”

Trends in total reflection X-ray fluorescence spectrometry for metallic contamination control in semiconductor nanotechnology

“…In comparison with independent techniques such as ICPMS and GFAAS [19,39,40], these studies have reported the tendency of TXRF to underestimate the metallic concentration. A very systematical decrease in the apparent TXRF accuracy has been observed as a function of the metallic content of the droplet residue; the effect starting typically above a total number of 3 × 10 13 -1 × 10 14 metal atoms in the residue (i.e.…”