Nanochannel system fabricated by MEMS microfabrication and atomic force microscopy

Area of Science:

• Nanotechnology
• Microfluidics
• Surface Science

Background:

• Nanochannels are crucial for nanoscale manipulation and analysis.
• Fabrication of precisely controlled nanochannels remains a challenge.
• Integrated electrodes are needed for electrical characterization and manipulation within nanochannels.

Purpose of the Study:

• To design and fabricate a silicon nanochannel system with integrated transverse electrodes.
• To demonstrate the functionality of the nanochannel for fluid flow and nanobead translocation.
• To investigate the electrical response of the nanochannel during nanobead passage.

Main Methods:

• Fabrication using micro-electro-mechanical systems (MEMS) micromachining and atomic force microscopy (AFM)-based nanolithography.
• Creation of a nanochannel with dimensions 30 µm long and 20 nm × 200 nm cross-section.
• Anodic bonding for sealing the nanochannel with a Pyrex cover.

Main Results:

• Verified continuous flow using fluorescein isothiocyanate solution.
• Demonstrated translocation of negatively charged nanobeads (approx. 20 nm diameter) using an external DC electric field.
• Observed a sharp increase in transverse electrical conductivity upon nanobead passage.

Conclusions:

• The fabricated silicon nanochannel system is functional for fluid transport and nanobead manipulation.
• The integrated electrodes allow for electrical detection of nanoscale events within the channel.
• This system shows promise for applications in sensing and molecular electronics.