Fabrication of 3D Direct-Taper for the Optimization of SiN Waveguides Edge Couplers

The performance of the coupling between integrated photonic waveguides and optical fibers defines one of the most important bottlenecks for the overall performance of photonic integrated circuit devices, compared to competing technologies. In this work, we present a novel fabrication technique to realize 3D direct-tapering of waveguides, which allows to increase of the optical mode dimensions in both the horizontal and the vertical directions, thus improving the overall efficiency of edge couplers with optical fibers compared to the traditional 2D design.