A Correlative ToF-SIMS/SPM Methodology for Probing 3D Devices.

Area of Science:

• Nanotechnology
• Materials Science
• Surface Science

Background:

• Miniaturization and complexity of nanodevices necessitate nm-scale 3D-spatial resolution characterization.
• Secondary Ion Mass Spectrometry (SIMS) lacks sufficient lateral resolution for advanced nanotechnology.
• Topographical changes during 3D SIMS analysis, caused by differential sputtering, hinder accurate 3D chemical imaging.

Purpose of the Study:

• To develop and evaluate a combined Scanning Probe Microscope (SPM) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) system.
• To overcome limitations in lateral resolution and topographical artifacts in 3D SIMS analysis.
• To enable accurate 3D chemical imaging of complex nanostructured materials.

Main Methods:

• Integration of a SPM module into a ToF-SIMS instrument.
• Alternating between SPM topography measurements and ToF-SIMS chemical analysis during depth profiling.
• Capturing time and spatially dependent surface erosion with high spatial resolution.

Main Results:

• The integrated SPM-ToF-SIMS system successfully acquired high-resolution topographical data.
• Demonstrated ability to correlate topographical changes with sputtering time and material composition.
• Significant improvements in the accuracy of 3D chemical imaging for complex systems were achieved.

Conclusions:

• Combining SPM and ToF-SIMS provides complementary topographical information essential for accurate 3D chemical analysis.
• The developed approach effectively mitigates artifacts arising from differential sputtering rates.
• This integrated technique offers a powerful solution for characterizing complex 3D nanostructures.