Process and materials characterization using low energy secondary ion mass spectrometry (SIMS)

Secondary ion mass spectrometry (SIMS) is a widely used metrology technique for the characterization of semiconductor materials. The shrinking of feature size has lead to a new generation of SIMS tools capable of accurately analyzing advanced process technology and new materials. These tools offer high depth resolution by using very low primary beam energies. Quadrupole based SIMS tools have proven to be the best choice for using low energy beams, as the design offers several key advantages: independent incidence angle and energy variation allowing optimization of die SIMS parameters for specific applications, low extraction fields allow low energy ions to reach the sample surface without distortion, high level of reproducibility is achieved on a routine basis and a low cost of ownership compared to other types of SIMS instruments. In this study, a quadruple SIMS tool (ATOMIKA 4500™) that has floating low energy ion guns (FLIG™) to generate the low energy ions, was used to analyze a variety of different samples. For example, shallow boron implants and SiGe HBT samples. This paper will discuss the benefits of using quadruple SIMS for analyzing these new materials in a manufacturing environment.