Automated and low cost method to manufacture addressable solid-state nanopores

Abstract

In this paper an easy, reproducible and inexpensive technique for the production of solid state nanopores, using silicon wafer substrate is proposed. The technique is based on control of pore formation, by neutralization etchant (KOH) with a strong acid. Thus, a local neutralization is produced around the nanopore, which stops the silicon etching. The etching process was performed with 7M KOH at 80°C, where 1.23 µm/min etchings speed was obtained, similar to those published in literature. The control of the pore formation with the braking acid method was done using 12M HCl and different extreme conditions: i) at 25ºC, ii) at 80°C and iii) at 80°C applying a potential. In these studies, it was found that nanopores can be obtained automatically, addressable and at a low cost. Additionally, a way to obtain the nanopores leaving the silicon wafer completely clean after the etching process was found. This method offers the possibility of an efficient scale-up from the laboratory to production scale.