Columbia University

Technology Ventures

Robust, consistent fabrication of nanoscale electrodes with molecular dimensions using a nanogap mask

Technology #m10-060

Single-walled carbon nanotubes (SWNT) are often used as electrodes in nanoscale electromechanical devices. These devices can be transformed into single molecule detectors by creating a deliberate gap in the nanotube. When single molecules in solution bridge this gap, they complete a circuit, and are detected. This detection technique is useful for many research applications; however, manufacturing these devices is inherently difficult. This technology outlines a robust fabrication process designed to create single-molecule-length breaks in a carbon nanotube. This is achieved via a self-aligning process that places a mask with a small gap above the nanotube, and cuts the tube using an oxygen plasma. The resulting gap can then be part of a molecular electronic switch for single molecule detection.

Reliable, reproducible fabrication of carbon nanotube electrodes allows consistent single molecule detection

Current fabrication methods for molecular SWNT devices are tedious and time-consuming. Imperfect carbon nanotube gaps can lead to a decrease in detection sensitivity. This technology’s self-aligning process allows the nanogap to be created reliably and reproducibly. This robust process yields highly uniform nanogaps of fewer than 10 nanometers, and was proven reliable over hundreds of devices.

This nanogap fabrication process has been demonstrated in the lab of Dr. Wind.

Lead Inventor:

Shalom J. Wind, Ph.D.


  • Molecular electronic switches sensitive enough to detect trace amounts of molecules in solution, e.g. DNA.
  • Fabrication process can be used to make templates for nanoimprint lithography.


  • Fabrication process produces a precise nanogap in the carbon nanotube.
  • Less tedious and time-consuming than conventional methods used to create nanoswitches
  • Retains consistency in gap uniformity even when production is scaled up

Patent information:

Patent Pending (US 20110268884)

Licensing Status:

Available for licensing and sponsored research support

Tech Ventures Reference: IR M10-060

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