Direct Laser Writing of Copper Micropatterns from Deep Eutectic Solvents Using Pulsed near-IR Radiation

Area of Science:

• Materials Science
• Additive Manufacturing
• Laser Processing

Background:

• Fabricating conductive patterns on dielectric substrates is crucial for microelectronics.
• Existing methods often face limitations in efficiency, resolution, or material compatibility.
• Deep eutectic solvents offer a promising medium for material synthesis and deposition.

Purpose of the Study:

• To develop an improved laser-induced synthesis method for fabricating electrically conductive copper patterns.
• To enhance processing efficiency and achieve arbitrary pattern topologies on dielectric substrates.
• To establish a complete, single-laser manufacturing cycle for copper pattern fabrication.

Main Methods:

• Utilized improved laser-induced synthesis from deep eutectic solvents.
• Implemented acceptor substrate pretreatment with laser-induced microplasma.
• Employed auxiliary glass substrates and optional laser post-processing.
• Used a single, commercially available, pulsed Yb fiber laser system.

Main Results:

• Achieved fabrication of electrically conductive copper patterns and films on dielectric substrates.
• Demonstrated a significant increase in processing efficiency through substrate pretreatment.
• Successfully created patterns of arbitrary topology.
• Observed laser-induced periodic surface structures (LIPSSs) on the fabricated tracks.

Conclusions:

• The developed method provides an efficient and versatile approach for copper pattern fabrication.
• The single-laser manufacturing cycle simplifies the production process.
• The observed LIPSSs offer potential for tuning the functional properties of the copper tracks.