Copper Electrode Material using Copper Formate-Bicarbonate Complex for Printed Electronics

Abstract

Copper ink has been prepared by mixing copper(II) formate and 2-ethyl-1-hexylammonium bicarbonate (EHABC) to overcome some weak points such as aggregation and degradation of copper nano-type ink. Ink was coated on glass substrate and calcined at 110 o C to 150 o C to generate electrically conductive copper film under two different atmospheres such as nitrogen gas and gaseous mixture of formic acid and methanol. The lowest resistivity of 1.88 ·cm of copper film was obtained at 150 o C in gaseous formic acid condition. The long-term resistivity shows to increase from 1.88 ·cm to 2.61 ·cm after one month.

Improved Behavior of Copper–Amine Complexes During Thermal Annealing for Conductive Thin Film Synthesis

“…It has a relatively easy mode of preparation and generates highly conductive film at low temperatures. Although, from a researcher's perspective and as shown in our previous work, such inks on glass substrate tend to move during thermal annealing which leads to the deformation of the printed pattern as viscosity increases at elevated temperatures. In this study, diamine (DA) was added in the formulation of the inks to preserve the conductive pattern throughout the annealing period.…”

“…Studies have been conducted to address this problem with oxidation through the introduction of capping agents to the formulation of inks . In addition, several procedures for the decomposition of inks to metallic form were modified such as laser sintering, calcination under nitrogen, hydrogen, and formic acid atmospheres.…”