AIR-GAP-BASED RF COAXIAL TSV AND ITS CHARACTERISTIC ANALYSIS

摘要

Many 3D IC applications such as MEMS and RF systems require Through-Silicon Via(TSV) with operations for high-speed vertical communication.In this paper,we introduce a novel air-gap coaxial TSV that is suiTab.for such RF applications.Firstly,the detailed fabrication process is described to explain how to acquire such a structure.Then,an Resistor Inductance Conductance Capacitance(RLGC) model is developed to profile the transverse electromagnetic field effect of the proposed air-gap TSV.The model is further verified by a 3D field solver program through the S-parameter comparison.With reference to the numerically simulated results,this analytical model delivers a maximum deviation of less than 6‰,on the conditions of varying diameters,outer to inner radius ratios,and SU-8 central angles,etc.Taking advantages of scalability of the model,a number of air-gap-based TSV designs are simulated,providing 1.6~4.0 times higher bandwidth than the conventional coaxial TSVs and leading to an efficient high frequency vertical RF interconnection solution for 3D ICs.