Development and Prospect of Coaxial Through-Silicon Via in 3D Integrated Circuits

Three-dimensional integration technology is characterized by high density, high performance, and multi-function, which has promoted the further development of integrated circuits. At present, there is an increasing demand for novel high-frequency vertical connections in 3D integrated systems. Using conventional through-silicon via (TSV) structures at high frequencies has limitations due to coupling noise and crosstalk. Therefore, coaxial TSV structures with self-shielding capability have great application prospects in wireless communication systems, RF modules, 5G applications, and other fields. Over the past decade, coaxial TSV structures have attracted widespread attention, and significant progress has been made in the study of their parasitic effects, equivalent circuit models, and transmission characteristics, and new structures and materials of coaxial TSV proposed to suit the needs of different three-dimensional integration applications. However, the difficulty of manufacturing has become a key bottleneck restricting the application of coaxial TSV. This article reviews the relevant research literature on coaxial TSVs, classifies and summarizes the main literature in recent years, focusing on the latest progress and challenges in coaxial TSVs in technology and equivalent circuit models, summarizes the advantages and disadvantages of coaxial or quasi coaxial TSVs with new structures or materials, and prospects the research prospects in these fields.