Copper Oxide Ink Composition for Stable Low-Resistance Conductive Films

The patent uses copper oxide particles as an intermediary substance between copper metal and the oxidizing environment. The copper oxide layer acts as a protective barrier that prevents further oxidation of the conductive copper particles, while still allowing the formation of conductive networks through sintering and particle aggregation.

The patent creates an inert environment by incorporating antioxidant agents and controlling the atmosphere during storage and processing. This prevents oxygen from reaching the copper particles, thereby maintaining low resistivity over time without requiring vacuum or inert gas packaging.

The patent optimizes the particle size of copper oxide to ultrafine ranges (1-100 nm), which fundamentally changes the sintering behavior. The ultrafine particles have higher surface energy and can sinter at lower temperatures and for shorter durations, overcoming the hindrance caused by antioxidation treatment.

The patent creates a composite structure where copper oxide particles are combined with organic antioxidants and binders. This composite material allows the copper oxide to maintain its reduced state while the organic components provide protection against oxidation and facilitate sintering through controlled decomposition.

The patent extracts and removes the photoresist step from the conventional manufacturing process. By using direct printing methods with copper oxide-based inks, the patent eliminates the need for photoresist application, exposure, and development steps, while still achieving precise circuit patterns through controlled deposition and sintering.

The copper oxide-based ink serves multiple functions: it provides the conductive material, acts as the pattern definition medium, and eliminates the need for separate photoresist and etching steps. This multi-functional approach simplifies the overall manufacturing process while maintaining precision.