Nanoscale coaxial focused electrohydrodynamic jet printing

Area of Science:

• Materials Science
• Nanotechnology
• Mechanical Engineering

Background:

• Controlled positioning of nanostructures is crucial for high-performance micro/nano-electromechanical systems (M/NEMS).
• Existing fabrication methods often face limitations in resolution, speed, or cost-effectiveness.

Purpose of the Study:

• To demonstrate a novel, high-resolution, high-speed, and cost-effective fabrication method for functional nanostructures.
• To achieve precise control over the placement and characteristics of printed nanostructures.

Main Methods:

• Development of a coaxial needle system for focused electrohydrodynamic jet printing.
• Utilizing a stable coaxial jet with inner functional ink and outer high-viscosity liquid to focus the jet to the nanoscale.
• Optimizing electrical and viscous forces to induce shearing and pressure for nano-jet focusing.

Main Results:

• Direct printing of nanostructures, including highly aligned nanowire arrays, nano-freebeams, and nano-cantilever beams, down to 40 nm scale.
• Achieved a high ratio of needle size (130 μm) to printed structure size (up to 3250:1).
• Printed lead zirconate titanate (PZT) nanostructures demonstrated pure perovskite structures and distinct piezoelectric responses.

Conclusions:

• Coaxial focused electrohydrodynamic jet printing offers a viable technique for controllable nanoscale fabrication using micrometer-sized needles.
• The method enables the precise creation of functional nanostructures for advanced M/NEMS applications.
• The printed PZT nanostructures show promising properties for piezoelectric applications.