Nanopore Fabrication by Controlled Dielectric Breakdown

Abstract

Nanofabrication techniques for achieving dimensional control at the nanometer scale are generally equipment-intensive and time-consuming. The use of energetic beams of electrons or ions has placed the fabrication of nanopores in thin solid-state membranes within reach of some academic laboratories, yet these tools are not accessible to many researchers and are poorly suited for mass-production. Here we describe a fast and simple approach for fabricating a single nanopore down to 2-nm in size with sub-nm precision, directly in solution, by controlling dielectric breakdown at the nanoscale. The method relies on applying a voltage across an insulating membrane to generate a high electric field, while monitoring the induced leakage current. We show that nanopores fabricated by this method produce clear electrical signals from translocating DNA molecules. Considering the tremendous reduction in complexity and cost, we envision this fabrication strategy would not only benefit researchers from the physical and life sciences interested in gaining reliable access to solid-state nanopores, but may provide a path towards manufacturing of nanopore-based biotechnologies.

Interfacing solid‐state nanopores with gel media to slow DNA translocations

“…Traditionally, nanopore fabrication has been done through the use of an ion beam, typically a transmission electron microscope (TEM) [16]. However, the creation of nanopores using a TEM is a complex method which includes the use of a high vacuum inside the TEM chamber (10 -5 Pa), focusing the electron beam on the membrane, and drilling the nanopore in such a way as to ensure pore formation by sputtering.…”

“…Recently, a breakthrough was achieved in the Tabard-Cossa lab which makes the entire process much simpler and less expensive [16]. This novel technique relies upon the phenomenon of dielectric breakdown of a thin SiNx membrane.…”

Nanopore Sensing

“…163 In this method, a constant potential is applied to the SiN x membrane immersed in solution to induce leakage current. It is important that the potential applied results in an electric field strength close to the membrane’s dielectric breakdown strength, i.e., 0.4–1 V/nm.…”

Solid-state nanopore localization by controlled breakdown of selectively thinned membranes

“…With that goal in view, we recently introduced a technique called controlled breakdown (CBD) as a means to fabricate pores rapidly, reliably, economically, and with high precision. [19–22] Since then, we have been exploring methods to enhance the functionality of this transformative new approach.…”

“…[19,21] Most standard nanopore-based sensors do not require pore positioning, but a number of specialized applications – including nanofluidic transistors, electrode-embedded devices,[23– 34] and plasmonic optical detection of analytes[35–38] – necessitate formation of the pore within a short distance of an existing structure on the membrane. Other applications require pore fabrication in a region of the membrane that has been locally thinned to maximize the signal amplitude of translocating biomolecules.…”