Optimization design of an electroabsorption modulator integrated with spot-size converter

A novel 1.55 μ spot-size converter integrated with electroabsorption modulator is designed and fabricated with conventional photolithography and chemical process. For the modulator, we employed a deeply-etched ridge waveguide structure with polyimide on each side of its walls. For the spot-size converter, we employed a buried double-core structure in which a ridge-based passive wavegude is incorporated. The wide and thim passive waveguide is optically combined with a laterally tapered active waveguide to control the mode size. By simulation, the figure of merit is 4. 17 (dB/V/ 100 μ) and the beam divergence angles in teh horizontal and vertical directions are as small as 11. 2† x 13. 0† respectively.