Fabrication and characterization on an organic/inorganic 2 × 2 Mach–Zehnder interferometer thermo-optic switch

•We optimized and fabricated an organic/inorganic hybrid thermo-optic switch.•The device reveals low switching power of 7.2 mW and fast response time of 100 μs.•The driving-noise-tolerance characteristics were investigated.•The minimum extinction ratio is larger 18 dB under a noise level of 2.5 Vpp.

An organic/inorganic hybrid 2 × 2 directional coupler (DC) Mach–Zehnder interferometer (MZI) thermo-optic (TO) switch was successfully designed and fabricated using simple direct ultraviolet photolithography process. The hybrid organic/inorganic waveguide structure includes poly-methyl-methacrylate-glycidyl-methacrylate (P(MMA-GMA)), SU-8 2005 and silica as core, upper cladding and under cladding, respectively. Device optimization and simulation were performed to decrease radiation loss and leakage loss, quicken response time and cut down power consumption. Measurements of the fabricated devices at 1550 nm wavelength result in a switching power of 7.2 mW, a response time of ∼100 μs, and crosstalk of −22.8 and −26.5 dB under cross state and bar state, respectively. Besides, the driving-noise-tolerance characteristics of this device were experimentally investigated by directly imposing a generated tunable noise on the pure driving signal (4 Vpp) and the minimum extinction ratio is larger than 18 dB under a noise level of 2.5 Vpp. The effect of noise on extinction ratio was found decreased with the increase of noise frequency.