High aspect ratio sharp nanotip for nanocantilever integration at CMOS compatible temperature

Area of Science:

• Materials Science
• Nanotechnology
• Mechanical Engineering

Background:

• Fabricating high aspect ratio (HAR) nanotips with small apex radii is challenging.
• Integrating nanotips with nano-mechanical structures requires precise and scalable methods.
• Existing Spindt tip fabrication methods often lack the required precision and density for advanced applications.

Purpose of the Study:

• To demonstrate a novel low-temperature nanofabrication approach for creating ultra-sharp, high-density nanotips.
• To integrate these nanotips onto nanoscale cantilever beams with high precision and yield.
• To enable CMOS-compatible parallel fabrication of nanotip-integrated nano-mechanical systems.

Main Methods:

• Utilized a low-temperature nanofabrication process.
• Fabricated nanotip structures comprising nanoscale thermally evaporated Chromium (Cr) Spindt tips on amorphous silicon rods.
• Integrated the nanotips onto 460 nm wide cantilever beams.

Main Results:

• Achieved nanotip apex radii as small as 2.5 nm.
• Fabricated 100 nm wide tips with aspect ratios exceeding 50 and densities greater than 5 × 10^9 tips/cm^2.
• Demonstrated high-precision, high-yield integration of HAR nanotips onto cantilever arrays.

Conclusions:

• The novel approach enables unprecedented sharpness and density in nanotip fabrication.
• This method allows for the first time, to our knowledge, the parallel and CMOS-compatible integration of HAR nanotips with nano-mechanical structures.
• Potential applications include on-chip high-speed atomic force microscopy and field emission devices.