A Study on the Breakdown Mechanism of an Electroless-Plated Ni(P) Diffusion Barrier for Cu/Sn/Cu 3D Interconnect Bonding Structures

Autor: Byunghoon Lee, Hoo-Jeong Lee, Seong-jae Jeon, Haseok Jeon, Kee-Won Kwon
Rok vydání: 2011
Předmět:
Zdroj: Journal of Electronic Materials. 41:109-114
ISSN: 1543-186X
0361-5235
DOI: 10.1007/s11664-011-1759-x
Popis: This study examined the thermal stability of an electroless-plated Ni(P) barrier layer inserted between Sn and Cu in the bonding structure of Cu/Sn/Cu for three-dimensional (3D) interconnect applications. A combination of transmission electron microscopy (TEM) and scanning electron microscopy allowed us to fully characterize the bonding morphology of the Cu/Ni(P)/Sn/Ni(P)/Cu joints bonded at various temperatures. The barrier suppressed Cu and Sn interdiffusion very effectively up to 300°C; however, an interfacial reaction between Ni(P) and Sn led to gradual decomposition into Ni3P and Ni3Sn4. Upon 350°C bonding, the interfacial reaction brought about complete disintegration of the barrier in local areas, which allowed unhindered interdiffusion between Cu and Sn.
Databáze: OpenAIRE