Study on low temperature welding of needle like copper based micro nano array materials and tin based solder

A surface needle like copper based micro nano array material structure was prepared by electroless plating. The copper needle array layer height was 1-3 μm, and the root diameter was 1-2 μm. This structure has been applied to Cu and tin based solder interconnects at low temperature and solid state. The strength, microstructure, chemical composition and shear strength of the interconnection interface were analyzed by scanning electron microscope, transmission electron microscope and welding strength testing instrument. Due to the mechanical interlocking force produced by needle like material structure and the formation of intermetallic compounds by solid atom diffusion, the interconnection quality is excellent.