Method to fabricate taper waveguide using fixed-beam moving stage electron-beam lithography

A method of tapering waveguides using fixed-electronic-beam-moving-stage (FBMS) paths is presented. The tapering is achieved by joining two FBMS paths to a common point. Compared to conventional area and FBMS tapering methods, the proposed method offers smooth and alignment-error-free tapering between waveguides of different widths. We experimentally demonstrate a fully functional FBMS patterned photonic circuit with a power splitter, wire-to-slot coupler, slot waveguide, and a slotted ring resonator. The device response with an insertion loss of -1.35 dB is measured around 1550-nm wavelength. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)