Low-temperature sintering of silver nanoparticles on paper by surface modification

Area of Science:

• Materials Science
• Nanotechnology
• Electronics Engineering

Background:

• Ultralow-temperature sintering is crucial for flexible printed electronics, enhancing flexibility and reducing energy use.
• Developing efficient sintering methods for silver nanoparticles (Ag NPs) at low temperatures remains a key challenge.

Purpose of the Study:

• To investigate ultralow-temperature sintering of large-sized Ag NPs using laser modification of substrate surfaces.
• To achieve high conductivity and mechanical stability in sintered Ag layers for flexible electronics.

Main Methods:

• Laser modification of substrate surfaces to create specific modified regions.
• Sintering of Ag NPs in conductive ink at a low temperature of 60 °C.
• Characterization of the sintered Ag layer's sheet resistance and folding endurance.
• Energy-dispersive X-ray spectroscopy (EDS) to analyze the composition and sintering mechanism.

Main Results:

• Ag NPs were successfully sintered at only 60 °C on laser-modified substrates.
• The sintered Ag layer achieved a low sheet resistance of 0.274 Ω.
• The flexible Ag layer demonstrated high durability, withstanding 10,000 folding cycles.
• Titanium dioxide (TiO2) formed by laser ablation was identified as a promoter for Ag NP sintering and substrate adhesion.

Conclusions:

• Laser modification of substrates enables efficient ultralow-temperature sintering of Ag NPs.
• The developed method is suitable for fabricating durable and conductive flexible printed electronics.
• A paper-based flexible integrated circuit board was successfully prepared, showcasing the practical application of this technique.