Ultra-Wideband Silicon Plasma Switches

The design, optimization, and characterization of an ultra-wideband solid-state plasma shunt switch with state-of-the-art performance is presented, achieving up to 5x reduction in dc power consumption, 4x faster switching speeds, and 2x smaller footprint compared to prior work. The switch is realized by patterning a coplanar waveguide transmission line on a high-resistivity silicon substrate and illuminating the gaps with up to three fibers, creating a highly efficient shunt switch. For efficient power consumption, multiple bias fibers are incorporated to distribute the light avoiding photoconductive saturation. Furthermore, to enhance agility, silicon micromachining is employed, achieving single-digit microsecond switching times under 2.75 mu s, the fastest ever recorded for this technology. The result is an ultra-wideband dc-110+ GHz shunt switch with less than 0.81 dB insertion loss and up to 71 dB isolation. This is accomplished with a straightforward manufacturing process in a compact footprint of less than 0.057 mm$<^>{2}$, paving the way for seamless technology integration. Lastly, highly accurate wideband co-simulations for solid-state plasma modeling are discussed and validated against measurements, underscoring the superior performance and reliability of this disruptive technology.