Solid-liquid Diffusion Interconnection Method Based on Cu-In Secondary Micro Nano Layer

Abstract

A solid-liquid diffusion interconnection method based on Cu-In secondary micro nano layer is proposed. The substrate surfaces of two copper indium secondary micro nano layers with special morphology are contacted with each other, and the contact area is heated to carry out solid-liquid interconnection. The special morphology of copper indium micro nano layer includes copper needle layer and indium micro layer coated on it. During interconnection, liquid indium infiltrates copper needle layer and forms intermetallic compound with good plasticity. The microstructure, intermetallic compounds and shear strength of the interface were analyzed by scanning electron microscope (SEM), transmission electron microscope (TEM) and welding strength tester. The results show that this solid-liquid interconnection method can obtain good interconnection quality and it is of great significance to green packaging.