Low temperature and low pressure Cu-Cu bonding with Ag doped Cu nanosolder paste

Abstract

In this paper, a novel Cu-Cu bonding method with Ag doped Cu nanosolder paste is proposed. The Cu nanoparticles were synthesized with an efficient method, and the nanosolder paste was fabricated by mixing synthesized Cu nanoparticles, commercial used Ag nanoparticles and organic solution. The shear strengths of Cu-Cu bonding with Ag doped Cu nanosolder paste and pure Cu nanosolder paste at the bonding temperature of 250 °C have been compared, and the highest shear strength in this work could achieve 20.32 MPa, which is suitable for 3D-IC packaging industry. The good performance showed by Ag doped Cu nanosolder paste makes it become a promising substitute of traditional Sn-Ag-Cu solder.