Amphiphilic silver particles for conductive inks with controlled wetting behavior

• Synthesis of amphiphilic silver particles.
• Surface modification of silver particles by amidation.
• Dispersion, contact angle, surface tension of silver inks.
• Aerosol jet printing of silver inks on polyimide.
• Conductivity by thermal and photonical annealing.

Silver inks find applications in printed electronics as conductive electrodes. Amphiphilic silver microparticles are prepared by modifying PAA-capped particles with functional amines via an amidation reaction. These modified silver particles can be dispersed in a wide variety of solvents ranging from water (ε = 80.4) to lipophilic alcohols (ε = 3–17) to yield conductive inks with tunable wettability. Using these inks, we have demonstrated aerosol jet printing of conductive silver patterns (36 μm wide, 1.2 μm thick) on Kapton. Electrical resistivity of 3.7 μΩ cm is obtained after thermal annealing at 225 °C for 5 min. Similar electrical resistivity (3.9 μΩ cm) is achieved after photonic annealing as short as 1 ms at 1.4 KV.