Nondestructive imaging of atomically thin nanostructures buried in silicon

Area of Science:

• Solid State Physics
• Materials Science
• Quantum Computing

Background:

• Atomically thin silicon dopant structures are crucial for quantum devices.
• Characterizing these buried nanostructures previously required destructive methods, hindering development.

Purpose of the Study:

• To introduce a non-destructive method for imaging and characterizing 3D dopant nanostructures in silicon.
• To assess the potential of scanning microwave microscopy (SMM) for fabricating quantum information processing devices.

Main Methods:

• Utilized scanning microwave microscopy (SMM) to image phosphorus nanostructures fabricated by scanning tunneling microscope lithography.
• SMM measurements were sensitive to as few as 1900-4200 densely packed P atoms.
• Employed finite element modeling to explore resolution enhancement strategies.

Main Results:

• Achieved non-destructive imaging and electronic characterization of 3D phosphorus nanostructures.
• Demonstrated SMM sensitivity to dopant atoms at depths of 4-15 nm below the silicon surface.
• Observed reduced carrier mobility in shallow dopant layers.

Conclusions:

• SMM provides a powerful, non-destructive tool for analyzing atomic-scale dopant structures.
• This technique can significantly aid the fabrication process for quantum computers, particularly surface code architectures.