Solid-State Nanopore-Based DNA Sequencing Technology

Figure 3

TEM and SEM images of various nanopores fabricated by typical and advanced technologies. (a) A 3.7 nm nanopore formed on free-standing SiN membrane by helium ion microscope (HIM) direct drilling technique [64]. Copyright © 2011, IOP Publishing. (b) A 1.8 nm SiN_x nanopore obtained by Ar-ion beam sculpting technique [65]. Copyright © 2001, Nature Publishing Group. (c) A graphene nanopore formed by FEB sculpting technique whose diameter was about 3.5 nm [31]. Copyright © 2008, AIP Publishing LLC. (d) A silicon nanoslit with feature size down to 13 nm fabricated by KOH wet etching process [73]. (e) Nanopore arrays manufactured by MaPE technique combined with nanoimprint lithography technology. Inset figure shows representative zoomed-in image of the nanopore arrays [76]. Copyright © 2012, American Chemical Society. (f) A 2 nm Al₂O₃ nanopore formed by ALD process [78]. Copyright © 2004, American Chemical Society. (g) ~18 nm nanopore created by electrodeposition process [79]. Copyright © 2010, IOP Publishing. (h) A FIB-fabricated nanopore shrunk from 1 μm to 25–30 nm by local oxide deposition method [81]. Copyright © 2006, John Wiley and Sons.

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