Reliability Improvement of high Temperature sintered Ag Die-Attachment by adding Sub-micron SiC Particles

Based on our previous research results, SiC-particle (SiC-p) added Ag sintering paste exhibits excellent high temperature reliability in Cu-Cu dummy bonding joints. Thus this paper explores the possibility of utilizing SiC-p added Ag paste as a novel high temperature die-attachment solution in actual situation. The bonding structure in this research is composed of Si dummy chips and a DBC (Direct bonded copper) substrate. Different additional amount (0~5%) of sub-micron SiC-p was added into a hybrid Ag paste in order to prepare a SiC-p/porous Ag compound structure. In earlier research, this structure had already exhibited stable cross-section morphology of both sintered Ag itself and of interfacial region. In addition to the Ag paste, the surface metallization of DBC substrate was also focused on in this research. Metallization was prepared separately by electroplating and sputtering and compared, and a Ti diffusion barrier layer was adopted. According to our results, SiC-p added Ag sintering paste shows better stability in extra-high temperature storage test and the Ti diffusion barrier layer plays an active role in the prevention of oxidation in ultra high temperature.