Pascal M. Seiler | Searcharxiv

arXiv2022

Dual-polarization multiplexing amorphous Si:H grating couplers for silicon photonic transmitters in the photonic BiCMOS backend of line

We report on polarization combining 2D grating couplers (2D GCs) on amorphous Si:H, fabricated in the backend of line of a photonic BiCMOS platform. The 2D GCs can be used as an interface of a hybrid silicon photonic coherent transmitter, which can be implemented on bulk Si wafers. The fabricated 2D GCs operate in the telecom C-band and show an experimental coupling efficiency of -5 dB with a wafer variation of +/-1.2 dB. Possibilities for efficiency enhancement and improved performance stability in future design generations are outlined and extension towards O-band devices is investigated as well.

physics.app-ph↗

arXiv2020

Cross-polarization effects in sheared 2D grating couplers in a photonic BiCMOS technology

We investigate numerically and experimentally sheared 2D grating couplers in a photonic BiCMOS technology with a focus on their splitting behavior. Two realization forms of a waveguide-to-grating shear angle are considered. The cross-polarization used as a figure-of-merit is shown to be strongly dependent on the grating perturbation strength and is a crucial limitation not only for the grating splitting performance, but also for its coupling efficiency.

physics.optics↗