Fabricating nanopores with diameters of sub-1 nm to 3â € nm using multilevel pulse-voltage injection

Abstract

To date, solid-state nanopores have been fabricated primarily through a focused-electronic beam via TEM. For mass production, however, a TEM beam is not suitable and an alternative fabrication method is required. Recently, a simple method for fabricating solid-state nanopores was reported by Kwok, H. et al. and used to fabricate a nanopore (down to 2â €...nm in size) in a membrane via dielectric breakdown. In the present study, to fabricate smaller nanopores stably - specifically with a diameter of 1 to 2â €...nm (which is an essential size for identifying each nucleotide) - via dielectric breakdown, a technique called multilevel pulse-voltage injectiona (MPVI) is proposed and evaluated. MPVI can generate nanopores with diameters of sub-1 nm in a 10-nm-thick Si 3 N 4 membrane with a probability of 90%. The generated nanopores can be widened to the desired size (as high as 3â €...nm in diameter) with sub-nanometre precision, and the mean effective thickness of the fabricated nanopores was 3.7â € nm.