Low-pressure Cu-Cu bonding using in-situ surface-modified microscale Cu particles for power device packaging

• DOI: 10.1016/j.scriptamat.2016.04.018
• Publication Date: 2016-04-27T12:03:33Z
• Authors: Xiangdong Liu; Hiroshi Nishikawa
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract An oxidation-reduction bonding (ORB) was applied to achieve Cu-Cu bonding with microscale Cu particle paste. During sintering at 300 °C, Cu2O nanoparticles were homogeneously formed on the surface of the microscale Cu particles through a thermal oxidation, and were subsequently reduced to Cu nanotextured surface in formic acid atmosphere. This in-situ surface modification significantly enhances the sinterability of the microscale Cu particles, leading to a well-sintered microstructure and a three times higher bonding strength than that of the bonding joints prepared with non-oxidation bonding (NOB).