Nanopore Fabrication via Transient High Electric Field Controlled Breakdown and Detection of Single RNA Molecules

The fabrication of nanopores through a dielectric breakdown method, achieved by simple, low-cost desktop setups, has promoted the research of solid-state nanopore sensing. This paper reports a method for fabricating nanopores. This method uses transient high electric field controlled breakdown (THCBD) to form electric-field-dependent nanopores with different diameters in the order of milliseconds. By manipulating a micropipette with a high electric field to establish the meniscus contact with the SiN membrane, nanopores can be formed through an "auto-brake" fabrication process. Compared with the traditional dielectric breakdown, THCBD can greatly shorten the breakdown time and form pores of different sizes under higher electric fields without causing additional damage to the SiN membrane. The nanopores formed by this method can be successfully used to detect two types of RNA molecules. One is transfer RNA from yeast extract and the other is a synthetic RNA oligonucleotide fragment (rArArArArArArArArArArArA).