Laser annealing of SiO2 film deposited by ICPECVD for fabrication of silicon based low loss waveguide

Laser annealing of silicon dioxide （SiO2） film formed by inductively coupled plasma enhanced chemical vapor deposition （ICPECVD）is studied for the fabrication of low loss silicon based waveguide. The influence of laser annealing on ICPECVD-deposited SiO2 film is investigated. The surface roughness, refractive index, and etch rate of annealed samples are compared with those of SiO2 film obtained by thermal oxidation. It is demonstrated that the performance of ICPECVD-deposited SiO2 film can be significantly improved by laser annealing. Al2O3/SIO2 waveguide has been fabricated on silicon substrate with the SiO2 lower cladding formed by ICPECVD and laser annealing process, and its propagation loss is found to be comparable with that of the waveguide with thermally oxidized lower cladding.