|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Advanced Microelectronic Packaging, Emerging Interconnection Technology, and Pb-free Solder
||Effective Control of the Statistical Spread in Cu TSV Extrusion by a Cap Layer
||Golareh Jalilvand, Omar Ahmed, Cullen Fitzgerald, Keenan Bosworth, Zhenlin Pei, Tengfei Jiang
|On-Site Speaker (Planned)
Via extrusion, especially its statistical spread, is an important reliability issue for TSV-middle 3D integration. As a novel approach to control extrusion, a thin metallic cap layer was applied on top of the via surface and an effective reduction in statistical variation of TSV extrusion height was demonstrated. Two cap materials, Co and W, were studied, and results showed that both were able to reduce the magnitude of extrusion considerably. More significantly, the spread of the extrusion values was much reduced for vias deposited with the Co cap layer. Further investigation on the mechanisms of observed extrusion reduction was carried out through thermo-mechanical characterizations and finite element analysis. Results suggested that being a known effective diffusion barrier for Cu interconnects, Co was able to suppress the mass transport causing extrusion near the top of the via, therefore improve the statistical distribution of via extrusion.
||Planned: Supplemental Proceedings volume