Paper Title
Signal Transmission Performance of TSV Stacked Die

Abstract
3-D integration technologies have been of increasing interest for compact and high performance system integration and packaging. Through-silicon-via (TSV) is one of the key technologies to enable vertical connections for stacked ICs and silicon packages. A TSV is a conducting copper nail, which provides an electrical connection though the substrate and is expected to be used extensively to provide high-speed interconnects between the top and bottom of the active dies. High speed signals on TSVs can interact with the active device area through a lossy substrate, causing circuit malfunctioning and signal integrity problems. This paper evaluates the effects of substrate conductivity on the electrical performance of 3D stacked die structures based on High Frequency Structure Simulator (HFSS) techniques. The results indicate the loss term is determined by the conductance of the silicon substrate. Thus, the high-resistivity material as the substrate can reduce the insertion loss of not only a TSV but also a horizontal interconnect on the substrate. Keywords- 3D Stacked-ICs, Through Silicon Via (TSV), High Frequency Structure Simulator (HFSS).