Invited Paper: Sintering Mechanism of Vapor Self-Assembled Multilayer (VSAM) Coated Cu Nano Particles for Application in Cu Nano Ink

Oxidation preventive Cu nano ink was prepared using a vapor self-assembed multi-layer coating method (VSAMs). These particles were prepared using 100 nm Cu nano particles coated with 1-octanethiol under ultrahigh vacuum condition with octanol used as a solvent. Octanol-based non-oxidized 10% (wt.) nano ink was well-dispersed without any surfactant. The conductive ink had good dispersion and remains stable for more than 6 weeks. It also has a low viscosity rating of 8.3 cPs. In addition, 5 mu L of copper nano ink was dropped into a 1 cm x 1 cm glass substrate to form a copper pattern. The copper pattern was then sintered at 350 degrees C in a tube furnace in a H-2 gas atmosphere. The resistivity of the film using the fabricated ink was determined to be 5.8 x 10(-6) Omega cm. The results show that the non-oxidized oxidation-preventive copper nano ink is suitable for ink-jet printing.