Manufacture tolerance analysis and control for a polymer-on-silicon Mach-Zehnder-interferometer-based electro-optic switch

Abstract:

To enhance the electro-optic (EO) modulation efficiency and realize the impedance-matching, a polymer-on-silicon multimode interference (MMI) Mach-Zehnder interferometer (MZI) -based electro-optic (EO) switch is designed and optimized. Under the central operation wavelength of 1550 nm, the driving voltages of the designed switch are 0 and ±1.375 V, respectively, with a short active region length of 5 mm, and the characteristic impedance of the electrode is about 49.6 Ω. The manufacture tolerance is analyzed for instructing the device fabrication. The results show that to realize ideal switching function, high fabrication accuracy on the buffer thickness, core thickness, electrode width and MMI waveguide width is extremely required, and a small voltage drift of −0.03 0.05 V is also expected for reducing the crosstalk to less than −30 dB. The allowed 3 dB bandwidth is 60 nm, and within this spectrum range, the insertion loss and crosstalk are less than 6.71 dB and −30 dB, respectively.