Diamond probe preparation for developing faster high-speed atomic force microscopy

Area of Science:

• Materials Science
• Nanotechnology
• Mechanical Engineering

Background:

• Single-crystal diamond (SCD) is a superior material for advanced sensing and imaging.
• Nanoscale fabrication of ultrathin, free-standing SCD devices is difficult.
• Existing methods face limitations in speed and precision for high-performance applications.

Purpose of the Study:

• To develop a universal hybrid micro/nanofabrication strategy for ultrathin SCD devices.
• To overcome performance limits in high-speed atomic force microscopy (HS-AFM).
• To enable fabrication of high-frequency, high-performance SCD cantilevers.

Main Methods:

• Combined high-throughput angled laser micromachining with focused ion beam refinement.
• Achieved precise geometric control and nanoscale surface flatness.
• Integrated amorphous carbon tips using electron-beam-induced deposition.

Main Results:

• Fabricated free-standing SCD cantilevers (∼7 × 2 × 0.08-0.15 μm³).
• Achieved resonance frequencies 3-4 times higher than commercial cantilevers (3.7-6.0 MHz).
• Demonstrated stable HS-AFM imaging of actin filaments at 25 fps.

Conclusions:

• The hybrid method enables scalable fabrication of high-performance diamond nanostructures.
• This approach advances ultrafast HS-AFM and nanomechanical sensing.
• Opens opportunities for micro- and nanoelectromechanical systems.