Influence of Silicon Via Morphology on RF Performance of TSV

Abstract

In order to study the influence of Silicon Through Via (TSV) morphology on RF performance, HFSS is used to model and simulate a single truncated cone shaped TSV. By using control single variable method, firstly, we change the radius difference $\Delta r$ between the TSV upper and lower ends to change TSV sidewall inclination angle $\theta$, and TSV shape; Then, fix $\theta$ and change TSV upper end radius, two insulation layers and substrate thickness h and then analyze RF performance changes. The simulation results show that the closer $\theta$ is to 90, the better the RF performance is; increasing h and TSV radius or appropriately reducing TSV sidewall insulation layer thickness can improve the electrical performance; moreover, increasing the insulation layer thickness on silicon surface alone or increasing the thickness of the two insulation layers which are integrally formed can also improve the RF performance, the impedance matching should be considered.