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

We investigated low-hydrogen SiN films prepared by a low temperature (350 degrees C) PECVD method. The impact of SiH4/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 1550nm with waveguide cross-section of 700nm x 400nm. 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. (C) 2008 Optical Society of America