Impurity control (SIMS)

Impurity control with SIMS - O depth profile in Si
Common microanalysis techniques such as Glow Discharge Mass Spectrometry fail to measure light elements (H, C, N, and O) because of high background signal limitations. Time-of-Flight SIMS can analyze atmospheric gas elements, but with mediocre detection limits only, due to a too low acquisition speed and contamination issues resulting from its intrinsic pulsed ion beam design.
Based on the dynamic SIMS technique, the IMS 7f-Auto is designed to achieve excellent detection limits on light element measurements, thanks to:
  • Continuous ion beam sputtering and magnetic sector mass spectrometer design providing extreme sensitivity;
  • UHV analysis chamber with optimized vacuum conditions, minimizing the background level created by residual gases;
  • Fully automated six-holder storage chamber providing high throughput as multiple samples can be pumped down and outgassed overnight;
  • High density Cs primary ion beam allowing high sputtering rates that significantly improve the detection limits.
Moreover, the IMS 7f-Auto offers depth profiling capabilities with high depth resolution and high throughput, and can provide information about uniformity with sub-micron lateral resolution.

Above: Excellent Oxygen detection limit in Si (low E16 at/cm3) using high 15keV impact energy Cs+ primary beam under different sputter rate (SR) conditions. Such depth profiles can be recorded up to several microns within minutes.