Measurement and Simulation of Ultra-Low-Energy Ion-Solid Interaction Dynamics

Area of Science:

• Materials Science
• Semiconductor Physics
• Nanotechnology

Background:

• Ion implantation is crucial for semiconductor manufacturing, but traditional methods struggle with precision for shrinking devices and new quantum technologies.
• Novel materials and quantum technologies demand higher precision in ion implantation regarding energy, ion species, and spatial accuracy.
• Current ion implantation techniques face limitations in achieving the required energy control and positional accuracy for next-generation electronics and quantum devices.

Purpose of the Study:

• To demonstrate and validate low-energy (1 keV) focused ion beam (FIB) gold (Au) implantation into silicon (Si).
• To investigate methods for achieving precise low-energy ion implantation while maintaining sub-micron beam focus.
• To compare experimental results with simulation models and highlight discrepancies in low-energy heavy-ion implantation simulations.

Main Methods:

• Focused ion beam (FIB) implantation of 1 keV Au ions into Si.
• Atom probe tomography (APT) for validating implant depth and distribution.
• Comparison of experimental data with SRIM (static) and TRIDYN/IMSIL (dynamic) simulations.
• Analysis of factors influencing simulation accuracy, such as lattice enrichment and sputtering.

Main Results:

• Achieved a precise Au implant depth of 0.8 nm at 1 keV in Si.
• Demonstrated that low-energy ion implants can be controlled by adjusting column voltage or ion deceleration bias.
• Identified a significant discrepancy between static and dynamic simulation models, attributed to lattice enrichment and surface sputtering.
• Highlighted the critical importance of model details for accurately simulating low-energy heavy-ion implantations.

Conclusions:

• The study successfully demonstrates precise 1 keV Au ion implantation into Si, achieving a shallow 0.8 nm depth.
• Results indicate that controlling ion energy via column voltage or deceleration bias is effective for low-energy, high-resolution implantation.
• Discrepancies in simulation models underscore the need for advanced modeling techniques for low-energy heavy-ion scenarios.
• The findings pave the way for significantly lower implantation energies while preserving high spatial resolution in semiconductor and quantum device fabrication.