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

Galina Georgieva; Christian Mai; Pascal M Seiler; Anna Peczek; Lars Zimmermann

doi:10.1007/s12200-022-00005-8

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

Front Optoelectron. 2022 Apr 21;15(1):13. doi: 10.1007/s12200-022-00005-8.

Authors

Galina Georgieva¹, Christian Mai², Pascal M Seiler^{3

2}, Anna Peczek⁴, Lars Zimmermann^{3

2}

Affiliations

¹ Hochfrequenztechnik-Photonik/Siliziumphotonik, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany. galina.georgieva@tu-berlin.de.
² IHP-Leibnitz Institut für innovative Mikroelektronik, Im Technologiepark 25, 15236, Frankfurt (Oder), Germany.
³ Hochfrequenztechnik-Photonik/Siliziumphotonik, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
⁴ IHP Solutions GmbH, Im Technologiepark 7, 15236, Frankfurt (Oder), Germany.

Abstract

In this paper, we report on polarization combining two-dimensional 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 toward O-band devices is also investigated.

Keywords: Amorphous silicon; Dual-polarization coherent communication; Hybrid integration; Photonic BiCMOS; Silicon photonics; Two-dimensional grating coupler (2D GC).