Quantitative Determination of Boron and Phosphorus in Borophosphosilicate Glass by Secondary Ion Mass Spectrometry

Secondary ion mass spectrometry (SIMS) using positive oxygen km bombardment and positive secondary ion spectrometry was applied to the quantitative depth profile analysis of insulating borophosphosilicate glass (BPSQ) films. The sample charging problem was alleviated by prior deposition of a thin gold layer onto the samples, use of an electron flood gun, and automatic sample voltage optimization. The SIMS results were compared to data acquired by wet chemical analysis and Rutherford backscattering (RBS), and excellent quantitative correspondence was obtained. The wet chemical analysis results were then used to calibrate the SIMS results quantitatively. In addition to the SIMS analytical procedures, the advantages of SIMS over conventional analytical techniques such as electron microprobe, wet chemical methods, and Auger electron spectroscopy are also discussed.