Studies on Quantification Analysis of Thin Film Layers (Si3N4, SiO2, and TiW) in Wafer Fabrication Using Energy-Dispersive X-Ray Microanalysis Technique and SEC Factors

Abstract Currently standardless EDAX ZAF quantification method has been widely used in many new generation FESEM machines. This method is able to provide good and reliable elemental results for bulk samples and some films for some particles and contamination analysis, but for some cases, EDX results may not be accurate, especially for thin film layer identification in wafer fabrication. In this paper, standardless EDAX ZAF quantification method will be further studied and an EDX quantification analysis method with the SEC factor correction will be introduced. The SEC factors can be calculated using current EDAX software. Application results from passivation thin film Si3N4, SiO2 layers and barrier metal thin film TiW layer show that the EDX results have been greatly improved after performing the SEC factor correction and the relative error is greatly reduced from 64.3–101% to 0.23–3.93% for passivation Si3N4 layer, from 51.5–62.3% to 0.73–3.10% for passivation SiO2 layer and from 18.2–77.0% to 0.04–11.5% for barrier metal TiW layer. If we assume that the passivation and barrier metal layers always have a stoichiometric composition, this method could be used for the monitoring purpose in wafer fabrication.