Thermally Driven Approach To Fill Sub-10-nm Pipettes with Batch Production

TL;DR

This paper presents a novel thermally driven method for batch filling of sub-10-nm nanopipettes, enabling improved nanotechnology applications by overcoming previous filling challenges.

Contribution

The study introduces a temperature-gradient technique for filling tiny nanopipettes with consistent pore sizes, applicable to various shapes, and validated by TEM and electrical measurements.

Findings

Effective removal of bubbles from nanopipettes using thermal gradients

Consistent pore size confirmation via TEM and conductance measurements

Potential for enhanced single-molecule detection and nanostructure imaging

Abstract

Typically, utilization of small nanopipettes results in either high sensitivity or spatial resolution in modern nanoscience and nanotechnology. However, filling a nanopipette with a sub-10-nm pore diameter remains a significant challenge. Here, we introduce a thermally driven approach to filling sub-10-nm pipettes with batch production, regardless of their shape. A temperature gradient is applied to transport water vapor from the backside of nanopipettes to the tip region until bubbles are completely removed from this region. The electrical contact and pore size for filling nanopipettes are confirmed by current-voltage and transmission electron microscopy (TEM) measurements, respectively. In addition, we quantitatively compare the pore size between the TEM characterization and estimation on the basis of pore radius and conductance. The validity of this method provides a foundation for highly sensitive detection of single molecules and high spatial resolution imaging of nanostructures.