A low-noise silicon nitride nanopore device on a polymer substrate

Area of Science:

• Nanotechnology
• Biophysics
• Materials Science

Background:

• Silicon nitride (Si3N4) membranes on silicon (Si) substrates are used for nanopore devices.
• These devices face challenges with dielectric noise, impacting signal sensitivity.
• Improving signal-to-noise ratio is crucial for sensitive biomolecule detection.

Purpose of the Study:

• To develop a novel low-noise nanopore device.
• To reduce dielectric noise in nanopore sensing.
• To enhance the detection capabilities for biomolecules like DNA.

Main Methods:

• Replaced the conventional Si substrate with a polymer (polyimide, PI) substrate.
• Fabricated a micro-hole in the PI substrate using laser machining.
• Transferred a thin Si3N4 membrane onto the PI substrate and formed a nanopore using a transmission electron microscope.

Main Results:

• Significantly reduced dielectric noise compared to Si-substrate devices.
• Decreased root-mean-square noise level from 146.7 pA to 5.4 pA.
• Successfully detected double-strand deoxyribonucleic acid (DNA) translocation with a high signal/noise ratio.

Conclusions:

• The polymer-substrate nanopore device offers substantially lower noise.
• This technology demonstrates high sensitivity for biomolecule detection.
• The device holds potential for future versatile sequencing applications.