Integrated Micro Coaxial Air-Lines with Perforations

Abstract- Three-dimensional micro coaxial transmission lines have been fabricated and measured on CMOS grade silicon wafers. One of the unique features of the structure is the perforated, coral-like outer shield and signal line which provides a means to control characteristic impedance and facilitates sacrificial layer removal after multi-layer deposition. These lines can thus be used to realize multilayer vertical interconnects with embedded MEM devices for RF to mm-wave frequencies. Measured S-parameters through 40 GHz for lines of varying impedance and perforation density are presented. Index Terms-micro coaxial, interconnects, MEMS transmission lines, suspended transmission line