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

Abstract

<p>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 O200 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.</p>

Topics

• impedance spectroscopy
• experiment
• simulation
• semiconductor
• nitride
• Silicon
• chemical vapor deposition