Silicon Nitride Photonic Particle Detector—Experiments and Model Assessment

Anton Buchberger, Paul Maierhofer, Felix Stollberger, Anderson Singulani, Martin Sagmeister, Omar Basso, Victor Sidorov, Jochen Kraft, Marcus Baumgart, Andreas Tortschanoff, Alexander Bergmann

Research output: Contribution to journalArticlepeer-review

Abstract

Sensors based on the interaction between analytes and the evanescent field of a silicon nitride waveguide are emerging in the field of bio-medical and environmental applications. We designed and implemented the first single particle detector based on this sensor principle that consists of a silicon nitride waveguide with sub-micron dimensions. The detection capabilities of the prototype were demonstrated with polystyrene latex (PSL) spheres equal to or greater than Ø200 nm. Single PSL spheres caused a decrease of the transmission through the waveguide from 0.2 up to 10%, depending on their diameter and position with respect to the waveguide. The experiments were supported by 3D finite element method (FEM) simulations of the particle-waveguide interaction. The simulated relative scattered power of a single sphere is in agreement with experimental results obtained from two different setups. The silicon nitride photonic chip was fabricated with a plasma-enhanced chemical vapor deposition (PECVD) process, which is compatible with established complementary metal-oxide-semiconductor (CMOS) processes for high-volume production. The demonstrator setup was realized with an external laser and photodetector, but with recent advances in light source and detector integration, our work leverages the realization of a fully integrated, low-cost photonic particle detector.
Original languageGerman (Austria)
Article number9448233
Pages (from-to)18829-18836
Number of pages8
JournalIEEE Sensors Journal
Volume21
Issue number17
DOIs
Publication statusPublished - 8 Jun 2021

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