Analysis of wideband multilayer LTCC vertical via transition for millimeter-wave System-in-package

Abstract

In order to understand of the relation between the configuration of vertical via interconnection and its transition properties, the performance of millimeter wave wideband vertical via interconnection is investigated in multilayer LTCC substrate in this paper. From physics-based equivalent circuit modeling approach, the equivalent circuit are related to the geometry directly, which is an efficient and intuitive analysis method. The matching pads and anti-pads are employed and optimized to realize impedance matching of vertical transition at a certain frequency range. Furthermore, in order to mitigate the radiation loss and the propagation of parallel-plate mode, the relationship between the signal transition performance and the distribution of ground vis is obtained. Based on above analysis, a millimeter-wave low loss microstrip-to-microstrip vertical via transition is designed and simulated by high-frequency simulator structure (HFSS). The simulated results indicates that the proposed structure exhibits better than −1.2 dB insertion loss from 5 GHz up to 60 GHz.