# Laser-Engineered Interfacial Dielectrophoresis-Aligned Nanowire Networks for Transparent Electromagnetic Interference-Shielding Films

## TL;DR

A new laser-based method aligns nanowires for transparent, high-performance electronic films with improved electromagnetic shielding.

## Contribution

A scalable interfacial dielectrophoresis and laser-welding method for precise nanowire alignment and enhanced performance.

## Key findings

- Sheet resistance of silver nanowire networks was reduced by ~46× with laser treatment.
- Electromagnetic interference shielding effectiveness reached 35 dB, a 1000× improvement over random networks.
- Optical transmittance increased by 10% in laser-treated nanowire films.

## Abstract

Nanowires (NW) hold substantial promise for high-performance
electronics;
however, the lack of programmable, deterministic control and alignment
strategies limits their seamless integration onto flexible target
substrates, posing challenges to manufacturing reliability, efficiency,
and scalability. Herein, we propose a scalable and adaptable interfacial
dielectrophoresis (i-DEP) method for precise translational and rotational
(0–150°) manipulation of NWs on thin polymer films. A
subsequent noncontact picosecond laser post-treatment is introduced
to effectively enhance electrical and optical properties by welding
NW junctions through controlled thermal diffusion and localized-field
confinement. The laser-welded silver nanowires (AgNW) network has
attained ∼46× reduction in sheet resistance and a 10%
enhancement in transmittance. The i-DEP aligned, laser-treated ultrathin
AgNW/polyimide film achieves 35 dB electromagnetic interference shielding
effectiveness, demonstrating over 1000× improvement compared
to randomly oriented drop-cast AgNW networks. The additional shielding
contribution arises from the capacitively coupled interwire network
in the predefined aligned-NWs structure, realizing performance beyond
that attainable by conductivity alone. This work presents a laser-engineered,
i-DEP-aligned NW network that reinforces interfacial NW network quality
and provides a systematic fabrication and optimization strategy for
advancing wireless, flexible, and high-performance transparent electronic
devices.