Low propagation loss SiN optical waveguide prepared by optimal low-hydrogen module

Abstract

We investigated low-hydrogen SiN films prepared by a low temperature (350 degrees C) PECVD method. The impact of SiH(4)/N(2) flow ratio and radio frequency power on the hydrogen content in the SiN films was studied. In this work, we demonstrated a low-loss sub-micron SiN waveguide by using the corresponding optimal SiN films. The propagation loss was found to be as low as -2.1+/-0.2 dB/cm at 1550 nm with waveguide cross-section of 700 nm x 400 nm. The results suggest that the SiN films grown by PECVD with low hydrogen can be used in photonics integrated circuits for new generation communications applications.

Multilayer Silicon Nitride-on-Silicon Integrated Photonic Platforms and Devices

“…The low waveguide losses in the O-band imply that the multilayer platform using PECVD can be useful for Ethernet and data center interconnects. Further loss reduction can be achieved by process optimization that reduces the hydrogen content during deposition [30]. Again, the 150 and 220 nm thick Si waveguides had similar losses of about 6 dB/cm.…”

Ultra-Low Loss Large Area Waveguide Coils for Integrated Optical Gyroscopes

“…5. The increased loss at lower wavelengths is due to the hydrogen present from the PECVD oxide [9]. At higher wavelengths the curve flattens, which our model indicates is a result of scattering loss.…”

“…As future work, this reduction could be combated with multiple waveguide layers, allowing for increased length and maximizing the area of the coil. Low loss and broadband vertical couplers have been demonstrated with this platform [9].…”

Amorphous silicon and silicon nitride channel optical waveguides

“…The motivation for fabricating optical devices on silicon substrates is mainly due to the mature silicon processing technology, with availability of low-cost high-purity wafers and the possibility of integrating these optical devices with microelectronic and/or micromechanical elements. In the last decade, amorphous silicon technology has been also involved in the fabrication of optoelectronic elements like optical waveguides, where the core materials, differently from devices based on SOI technology, can be directly grown on the substrate/cladding layer [1,2]. Furthermore, the compatibility with standard CMOS processes opens up new possibilities to replace electrical by optical interconnects, in order to reduce the power consumption of microprocessors and other functional devices [3].…”