UNCG Research

Innovation in Nanotechnology – Ultrafocused Ion Beam Milling of Solid-State Nanopores

Posted on Wednesday, June 27th, 2012 by UNCG Research.

This technology is available through the UNCG Office of Innovative Commercialization

The global molecular diagnostics market should reach U.S. $15 billion by 2014. Reducing sample volume, improving sensitivity, and increasing the speed of biological detection continue to drive the development of technologies for improved diagnostics.

Solid-state nanopores (thin, fabricated membranes with nanoscale holes capable of facilitating single molecule analysis) provide an enabling platform technology to develop the next wave of biological diagnostics. Current solid-state methods of nanopore production include ion beam sculpting, transmission electron milling (TEM) ablation, and focused ion beam (FIB) milling. These methods typically take minutes to hours to perform and are limited to a single device per application.

Researchers at The University of North Carolina at Greensboro (UNCG) and industry partners have collaborated to develop a rapid, precise technique for the fabrication of solid-state nanopores for biomolecule detection. Using a scanning helium ion microscope, UNCG researchers have demonstrated the controlled fabrication of solid-state nanopores in thin SiN membranes. The output of this technology is highly repeatable and reliable for producing nanopores with diameters as low as 4nm.


  • Highly repeatable process allows for fabrication of nanopores in parallel arrays or single pores in a device chip.
  • Capable of producing solid-state nanopores rapidly (milliseconds to seconds per pore).
  • Process allows for greater control over thickness through the use of a low ion dose over a defined area prior to nanopore creation.
  • Amenable to other solid state membrane materials.
  • Allows for thinning of membrane and pore formation in same processing step.


The technology is a high-speed, high-throughput process capable of producing solid-state nanopores in thin, predefined membranes with precise control over pore size. The fabrication is achieved through direct, lithographically-defined milling using a focused helium beam produced by an atomically sharp metal cathode. The technology takes advantage of a motorized stage with a large range of motion, allowing for production of nanopores in multiple membranes without having to vent  the chamber between runs, therefore reducing preparation time. The researchers have demonstrated how this technology can be used to detect electrically the translocation of biomolecules (double stranded DNA) through the nanopores. This technology has wide applications in the study of other types of biomolecules (e.g. proteins)  or nanoparticles (e.g. nanotubes/nanowires.)


Dr. Adam Hall’s interests fall at the intersection of nanotechnology and biophysics. His lab is developing novel fabricated structures at the nanometer scale for use in detecting, manipulating, and probing single biological molecules.

His current research involves:

  • molecular detection and analysis using solid-state nanopores
  • single molecule force spectroscopy
  • detection of nucleic acid-binding entities
  • nanoelectromechanical devices

Dr. Hall earned his Ph.D. in Applied and Materials Sciences at the University of North Carolina at Chapel Hill and completed his post-doctoral training in the laboratory of Dr. Cees Dekker at the Kavli Institute of Nanoscience, TU Delft, Netherlands.


UNCG’s Office of Innovation Commercialization seeks to stimulate development and commercial use of UNCG-developed technologies. UNCG is flexible in its agreements, and opportunities exist for joint development, academic or commercial licensing (exclusive, non-exclusive, and field-of-use), publishing, or other mutually beneficial relationships. UNCG is pursuing intellectual property protection for this innovation.

For More Information

If you would like more information about this technology or the University of North Carolina at Greensboro’s technology transfer program, please contact:Staton Noel
Office of Innovation Commercialization
University of North Carolina at Greensboro

1613 MHRA Building
P.O. Box 26170
Greensboro, NC 27402-6170336.256.1041

06.26.12 Reference # 11-0029