Metal Proportion Optimization of Annular Through-Silicon via Considering Temperature and Keep-Out Zone

For annular through-silicon via (TSV)-based 3-D integrated circuits (3-D ICs), a greater TSV metal proportion of annular TSV leads to lower temperature but induces larger keep-out zone (KOZ). In this paper, the figure of merit (FOM) tradeoff model between temperature and KOZ is proposed to obtain the optimal metal proportion of annular TSV. First, the analytical models of the temperature of annular TSV-based 3-D IC and the KOZ induced by annular TSV are given, respectively, and both of them are verified by ANSYS software. Second, based on the analytical models, the FOM model is proposed. Then, the effects of total radius, material, and insertion density of annular TSV on FOM and optimal metal proportion are analyzed in detail. It is concluded that, the optimal metal proportion of annular TSV is approximately 0.3 with large ranges of the total radius and density of annular TSV, and various materials filled in annular TSV.