Photonic crystal waveguides on silicon rich nitride platform

Abstract

We demonstrate design, fabrication, and characterization of two-dimensional photonic crystal (PhC) waveguides on a suspended silicon rich nitride (SRN) platform for applications at telecom wavelengths. Simulation results suggest that a 210 nm photonic band gap can be achieved in such PhC structures. We also developed a fabrication process to realize suspended PhC waveguides with a transmission bandwidth of 20 nm for a W1 PhC waveguide and over 70 nm for a W0.7 PhC waveguide. Using the Fabry-Pérot oscillations of the transmission spectrum we estimated a group index of over 110 for W1 PhC waveguides. For a W1 waveguide we estimated a propagation loss of 53 dB/cm for a group index of 37 and for a W0.7 waveguide the lowest propagation was 4.6 dB/cm.

Silicon Nitride Photonics for the Near-Infrared

“…With the aim of exploiting the large nonlinear response of the Si-rich silicon nitride, we employed this material for the fabrication of PhC waveguides [48] and high-Q PhC microcavities [49], [50]. The PhC membrane was obtained in a 300 nm thick film of material with a refractive index n=2.48 patterned with a triangular lattice of air holes of period a=580 nm and radius r = 0.3a.…”

The Emergence of Silicon Photonics as a Flexible Technology Platform

“…Devices fabricated on SiN have shown high insensitivity to temperature variations while achieving propagation losses below 2 dB/cm in the MIR and well below 1 dB/cm in the visible and telecom wavelength ranges [108]- [111]. Furthermore, SiN with a high silicon content has demonstrated the potential for fabrication of devices with enhanced nonlinear response and low nonlinear losses such as photonic crystal waveguides and cavities [112], [113].…”

Low-loss, compact, spot-size-converter based vertical couplers for photonic integrated circuits

“…For example, SiN allows the fabrication of low-loss array-waveguide gratings (AWGs) for wavelength-division multiplexing (WDM) [9]. Moreover, due to the low refractive index (n SiN = 1.875 at 1550 nm) and low TOC (α SiN = 1.7 × 10 −5 K −1 ) [10], SiN is more suitable than silicon for wavelength-selective elements such as gratings [11], ring-resonators [12] and photonic crystals [13], for example as mirrors in hybrid laser technology [11]. However, the direct co-planar integration of SiN with silicon waveguides limits the pattern density and scalability [14].…”