Title :
Effects of SiO2 hard masks on si nanophotonic waveguide loss for photonic device integration
Author :
Ng, Doris Keh Ting ; Qian Wang ; Kim-Peng Lim ; Jing Pu ; Kun Tang ; Yicheng Lai ; Chee-Wei Lee ; Seng-Tiong Ho
Author_Institution :
Data Storage Inst., A*STAR (Agency for Sci., Technol. & Res.), Singapore, Singapore
Abstract :
As the basic building block for photonic device integration, silicon nanophotonic waveguide requires low-loss propagation for high-performance ultra-compact photonic device. We experimentally study silicon dioxide hard masks grown by two different methods, i.e., thermal oxidation and plasma-enhanced chemical vapor deposition (PECVD) for silicon nano-waveguides fabrication and their effects on the propagation loss. It is found that the denser and smoother quality of thermally grown silicon dioxide increases the etch selectivity against silicon and reduces the line edge roughness transferred to the silicon nano-waveguide sidewalls, hence resulting in a lower loss as compared with the PECVD silicon dioxide hard mask. With thermally grown silicon dioxide as a hard mask, the silicon nano-waveguides loss can be halved for a 650-nm-wide nano-waveguide, and the loss is comparable with a waveguide fabricated with a resist etch mask.
Keywords :
etching; integrated optics; masks; nanophotonics; optical fabrication; optical waveguides; oxidation; plasma CVD; silicon compounds; PECVD; SiO2; etch selectivity; hard masks; line edge roughness; nanophotonic waveguide loss; photonic device integration; plasma-enhanced chemical vapor deposition; propagation loss; resist etch mask; silicon nanowaveguides fabrication; size 650 nm; thermal oxidation; Loss measurement; Optical losses; Optical waveguides; Photonics; Propagation losses; Resists; Silicon; Dielectric materials; loss measurement; optical waveguides;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2013.2287276