High Frequency Analysis of Cu-CNT Based Tapered TSV Bumps

In latest development of three-dimensional integrated circuit technology, tapered through silicon via (TSV) bumps are becoming a popular alternative to traditional cylindrical structure due to extremely low coupling and volume fraction, which leads to reduced crosstalk delay and better signal integrity. The tapered TSV bump structure is filled with Cu-CNT composite, which can exhibit better mechanical, thermal and electrical properties. The electrical equivalent for tapered TSV has been modeled along with redistribution layer (RDL). In this work, crosstalk and power loss analyses have been carried out. Further, we report that Cu-CNT composite TSVs outperform Cu and CNT TSVs. In addition, analysis of the different bump structures has been presented in this paper.