Solid-state nanopore fabrication in LiCl by controlled dielectric breakdown.

Area of Science:

• Materials Science
• Nanotechnology
• Biophysics

Background:

• Controlled dielectric breakdown (CDB) fabricates solid-state nanopores.
• This method relies on trap-assisted current tunneling for pore creation.
• Traditional methods use potassium chloride (KCl) buffer.

Purpose of the Study:

• To investigate the fabrication of nanopores using lithium chloride (LiCl) buffer.
• To evaluate the impact of LiCl on nanopore structure and stability.
• To assess the performance of LiCl-fabricated nanopores in biosensing applications, specifically DNA detection.

Main Methods:

• Fabrication of silicon nitride (SiNx) nanopores using CDB in LiCl buffer.
• Characterization of nanopore structure and uniformity.
• Conducting DNA translocation experiments in both LiCl and KCl buffers for comparison.

Main Results:

• Direct fabrication in LiCl yields uniform, symmetric, cylindrical nanopores.
• LiCl buffer reduces the need for overnight pore stabilization.
• Nanopores fabricated in LiCl show increased double-stranded DNA (dsDNA) transport duration compared to KCl.
• A 3-fold increase in LiCl concentration resulted in a 10-fold increase in dsDNA transport duration.

Conclusions:

• Fabricating nanopores in LiCl buffer is a viable alternative to KCl.
• LiCl buffer enhances nanopore quality and stability for in situ experiments.
• This method offers improved performance for biosensing applications like dsDNA detection.