Compact and High-Resolution 256-Channel Silicon Nitride Based AWG-Spectrometer for OCT on a Chip

We present the design, simulation, and technological verification of a compact 256-channel, 42-GHz silicon nitride based AWG-spectrometer dedicated to the realization of an on-chip spectral domain optical coherence tomography (SD-OCT) system. The spectrometer was designed for TM-polarized light with a central wavelength of 850 nm and fabricated with CMOS foundry processes. Spectrometer features small size of (13 × 14) mm
²
and high resolution of 0.1 nm.