3-D impedance matching network (IMN) based on through-silicon via (TSV) for RF energy harvesting system

Radio Frequency Energy Harvesting (RFEH) system can harvest radio frequency (RF) energy from the natural environment, showing potential applications to play the role of the battery in specific settings, such as outdoors or human body, demonstrating vast potential applications on the scenarios with difficulty to renew the traditional battery. In the RFEH system, Impedance Matching Network (IMN) consumes substantial amounts of metal wire and chip area in standard CMOS process and is not easy to be integrated into the monolithic substrate. The planar structure shows the shortcoming of large area and prominent parasitic influences, limiting its integration in the REFH system. The development of 3-D integrated circuit technology based on Through-Silicon Vias (TSV) offers a possible solution for RF passive devices. In the paper, a novel TSV-based 3-D IMN is designed. The capacitor is implemented with the TSV structure, while the inductor is designed with Redistribution Layer (RDL) spiral pattern. The co-design of 3D LC matching circuit shows the merits of the proposed solution, including high performance and compact size. It can be used as a technical solution for the integration of IMN in a monolithic CMOS RFEH system.