Design of a MEMS heterogeneous integrated switch filter bank

This paper presents a heterogeneous integrated micro-electro-mechanical system (MEMS) switching filter bank with silicon as the substrate. The silicon-based MEMS filter has the advantages of high Q value and low fabrication cost. The design solves the problem of large size and low integration of conventional filters. The filter bank is heterogeneously integrated between silicon by means of four filters layered two by two on the top and the bottom. A through silicon via (TSV) method is used to conduct the RF signal from the upper or lower layer to the output of the middle layer. The size of this assembly is significantly reduced without compromising the out-of-band rejection. In addition, this module improves the inter-channel isolation of the filter bank to a certain extent due to the low reflection effect of the coupling between the silicon on the RF signal.