Quantitative trace metal analysis of silicon surfaces by ToF-SIMS

✍ Scribed by Douglas, M. A.; Chen, P. J.

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 249 KB
• Volume: 26
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199812)26:13<984::aid-sia446>3.0.co;2-k

✦ Synopsis

Volumetric relative sensitivity factors (RSFs) are determined for 52Cr, 56Fe and 58Ni in an silicon O 2 '-formed oxide using a 12 keV Ga' primary ion beam, and the inÑuence of matrix oxygen content on these RSF values is evaluated. A multivariate expression for RSF values as a function of oxygen content is developed. Si 2 '-referenced This expression indicates that 12 keV Ga' ion beam RSF values for 52Cr, 56Fe and 58Ni in oxide at O 2 '-formed 1.0 nm depth are in excellent agreement with well-established 8 keV RSF values in a silicon matrix. Because O 2 ' calculated RSF values for oxide at 1.0 nm depth and native silicon oxide are almost equivalent, O 2 '-formed time-of-Ñight (ToF) SIMS metal RSF values and detection limits in native oxide for a Ga' liquid metal ion source are predicted, using the well-established 8 keV RSF values for metals in a silicon matrix. Time-of-Ñight O 2 ' SIMS silicon surface detection limits of 5 Â 106 to 5 Â 108 atoms cm-2 0.5 nm are predicted for most metals = of interest to the semiconductor community.