@inproceedings{FuenningPeczekKrohetal.2025, author = {F{\"u}nning, Tabea and Peczek, Anna and Kroh, Aleksandra and Mai, Christian and Paul, Martin and Thomsen, Florian and Tannenberg, Robert and Schumann, Christoph and Weller, Michael G. and Mai, Andreas and Steglich, Patrick}, title = {Optimization of local backside released micro-ring resonators for sensing applications using silicon photonic integrated circuits in a SOI technology}, series = {Proceedings of SPIE : Optical Sensors 2025}, volume = {13527}, booktitle = {Proceedings of SPIE : Optical Sensors 2025}, editor = {Baldini, Francesco and Homola, Jiri and Lieberman, Robert A.}, publisher = {SPIE}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-20449}, year = {2025}, abstract = {Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors.}, language = {en} }