Facile synthesis of high silver content MOD ink by using silver oxalate precursor for inkjet printing applications

• Facile synthesized high silver content MOD ink by using silver oxalate precursor.
• Microstructure and resistivity of films at various post-heat treatments were studied.
• Printed lines show low resistivity and good adhesion on PI substrate.

In this paper, a particle-free MOD ink (MOD = metal–organic-decomposition) of high silver content was directly used for inkjet printing silver conductive patterns on PI substrate. The ink was synthesized by using silver oxalate as precursor, ethylamine as a complexing ligand, ethyl alcohol and ethylene glycol as the solvent. The chemical and physical properties of the solution ink were investigated. The MOD ink has 27.6 wt.% of silver. The deposited films on PI substrate were thermally treated at a range of temperatures and times, and then analyzed in terms of their morphology and resistivity. The silver film cured at 170 °C for 30 min had a resistivity of 8.4 μΩ·cm. The printed patterns on PI substrate cured at 150 °C for 30 min showed metalized silver with low resistivity (8.6 μΩ·cm), high reflection, and good adhesion.