2×2 silicon-based waveguide optical switch driven by mems electrostatic actuation

To overcome the limitations of current technologies, including the slow switching speed, heat accumulation, and high power consumption of thermo-optic waveguide switches, the high transmission loss of electro-optic waveguide switches, and the complex feedback control, difficulty in large-scale array integration, and narrow operating bandwidth commonly found in traditional photonic integrated circuit (PIC) waveguide switches, to meet the future demands of on-chip all-optical switching technologies for optical switches with fast response, low power consumption, broad bandwidth, low cost, and large-scale array fabrication capabilities, this study investigates micro-electro-mechanical systems (MEMS) driven silicon-based waveguide optical switch devices. By integrating silicon photonic waveguide technology with MEMS technology, we designed and fabricated an electrostatically driven MEMS 2×2 silicon waveguide optical switch (silicon photonic MEMS switch) capable of routing optical signals. The monolithic integration of silicon photonic waveguides and MEMS microactuators on a silicon wafer was achieved using electron-beam lithography combined with complementary metal-oxide-semiconductor (CMOS) processes. With a footprint of 192 μm × 192 μm, the device successfully demonstrated 2×2 optical switching functionality. The switching response times were measured at 20 μs and 15 μs, with optical signal rise and fall times of 15 μs and 10 μs, respectively. At a wavelength of 1550 nm, the device achieved an extinction ratio (ER) of 35 dB and an insertion loss (IL) of −0.8 dB. Over the 1500–1600 nm wavelength band, the ER remained above 20 dB, and the holding power consumption in the ON state was less than 0.5 μW. Experimental results demonstrate that this silicon photonic MEMS optical switch features fast response, low modulation power consumption, and excellent broadband performance. Furthermore, it can be fabricated into large-scale arrays with simple control mechanisms using existing process platforms, indicating significant application potential in future on-chip all-optical switching networks.