Solid-state nanopore fabrication by automated controlled breakdown

Solid-state nanopores are now well established as single-biomolecule sensors that hold great promise as sensing elements in diagnostic and sequencing applications. However, until recently this promise has been limited by the expensive, labor-intensive, and low-yield methods used to fabricate low-noise and precisely sized pores. To address this problem, we pioneered a low-cost and scalable solid-state nanopore fabrication method, termed controlled breakdown (CBD), which is rapidly becoming the method of choice for fabricating solid-state nanopores. Since its initial development, nanopore research groups around the world have applied and adapted the CBD method in a variety of ways, with varying levels of success. In this work, we present our accumulated knowledge of nanopore fabrication by CBD, including a detailed description of the instrumentation, software, and procedures required to reliably fabricate low-noise and precisely sized solid-state nanopores with a yield of >85% in less than 1 h. The assembly instructions for the various custom instruments can be found in the Supplementary Manual, and take approximately a day to complete, depending on the unit that the user is building and their level of skill with mechanical and electrical assembly. Unlike traditional beam-based nanopore fabrication technologies, the methods presented here are accessible to non-experts, lowering the cost of, and technical barriers to, fabricating nanoscale pores in thin solid-state membranes. This Protocol describes a low-cost and scalable solid-state nanopore fabrication method, termed controlled breakdown (CBD), for fabricating solid-state nanopores.