Direct laser writing of strip waveguide in sol-gel film

In order to study the application of laser direct writing technology in the fabrication of strip optical waveguides,the SiO2-TiO2 strip waveguides based on silicon were manufactured using a continuous fiber laser with the wavelength of 1.07μm.The mechanism on the fabrication of strip waveguides by laser direct writing was discussed.The effect of the laser parameter on the width of waveguides was studied.Finally,the propagation mode field and optical loss at the wavelength of 1550nm were measured.The results indicate that the width of strip waveguide increases with the increase of laser power density and the decrease of laser scan velocity at the range of 0.1mm/s~1mm/s.There is no evident influence on the width of the strip waveguide when the laser scan velocity is higher than 1 mm/s.The strip waveguide with a height of 0.4μm and a width of 120μm was obtained by laser direct writing at the optimized parameters.The mode field in the optical waveguide is multi-mode at the wavelength of 1550 nm.The minimum propagation loss is 1.7dB/cm.