Design of 160-Channel Si3N4 based AWG-Spectrometer for Medical Applications

D. Seyringer, C. Burtscher, J. Edlinger, A. Maese-Novo, P. Muellner, R. Hainberger, J. Kraft, G. Koppitsch, G. Meinhardt and M. Sagmeister
Vorarlberg University of Applied Sciences,
Austria

Keywords: arrayed waveguide gratings, AWG, AWG design, silicon nitride waveguides, medicinal applications, photonics, high-channel AWG, Si3N4 AWG, optical spectrometer, high-index contrast AWGs

Summary:

We present the design of 160-channel, 50-GHz Si3N4 based AWG applying our proprietary AWG-Parameters tool. For the simulations of the AWG layout, we used PHASAR photonics tool from Optiwave. The simulated transmission characteristics were then evaluated applying our AWG-Analyzer tool. The AWGs were designed for TM-polarized light with a central wavelength of 850 nm. This design is based on the previous study of the various AWGs designs (8-channel, 100-GHz; 20-channel, 50-GHz; 40-channel, 50-GHz and 80-channel, 50-GHz AWGs), which were also technologically proven. The simulated results show very satisfying optical properties of the designed AWG. The final layouts were already sent to our technological partner for the fabrication. The goal of the silicon nitride waveguide based AWG development is to take a significant step towards the integration of spectral domain optical coherence tomography (SD-OCT) system operating in a wavelength range of 800 nm to 900 nm and having 0.1 nm resolution. OCT is a contact-free imaging method, which has become significantly important in ophthalmology to visualize the retina. In the course of the project, key-components of an SD-OCT system will be integrated on a single optical waveguide chip employing CMOS compatible processes.