Metallic bonding methodology for heterogeneous integration of optoelectronic dies to CMOS circuits

A metallic bonding methodology appropriate for wafer-level optoelectronic die to complementary metal oxide semiconductor (CMOS) circuit integration is introduced. A thin multilayer structure of the Au–20Sn eutectic alloy along with a starting layer of a rare-earth element (Gd) is utilized. Its main advantage is the accomplishment in a single step of both mechanical bonding and electrical interconnection of the heterogeneous devices. Bonding quality assessment and electrical parameters measurements are presented.