Fabrication of nanopores using electron beam

Abstract

Sub-5 nm nanopores are widely used in singlemolecule detections for biological and chemical applications. However, the traditional fabrication methods are difficult to reduce pore size to sub-5 nm. Focused electron beam irradiation inside a transmission electron microscope (TEM) is verified experimentally to be an effectively straightforward way to fabricate such small pores. The fabrication process can be explained by a simple physical collision model. We also fabricate graphene nanopores under various temperatures. The results verify that drilling at high temperature and direct thermal heating treatment can be beneficial to fabricate carbon nanostructure with high crystallization, which will promote the study of biological measurement. High temperature could also modulate the duration of fabrication, which can enhance the size control during nanopore fabrication.

Carbon nanopores for DNA sequencing: a review on nanopore materials

“…To obtain smaller graphene nanopores such as those with the sizes of sub-5 nm, shrinkage of the graphene nanopores has been realized in the temperature range of 400–1200 °C by setting the irradiation energies. 131 To further increase the crystallization of the graphene layers, various pore-forming temperatures have been applied in the apparatus. The utilization of a helium ion beam (HIM) led to the generation of ultrasmall (∼3.7 nm) graphene nanopores given that the diameter of the ion source beam can reach as small as ∼0.5 nm with an accelerating voltage of 30–35 kV (Fig.…”