Silicon-on-Insulator Substrates as a Micromachining Platform for Advanced Terahertz Circuits

This paper presents a comprehensive overview of the development and utilization of a micromachined silicon-on-insulator (SOI) fabrication process that has enabled the development of terahertz (THz) frequency superconducting-insulator-superconducting (SIS) and hot-electron bolometer (HEB) mixers, broadband directional couplers, on-wafer probes, as well as several multipliers. Through the detailed presentation of these circuits, it is demonstrated that ultrathin silicon is able to provide the required characteristics to enable the heterogeneous integration of multiple device technologies that is likely to be required for future THz system-on-chip (T-SoC) development.