Abstract
Ta_2O_5 thin film waveguides were prepared by RF magnetron sputtering system onto the fused quartz substrates. As- sputtered Ta_2O_5 films have a refractive index of n=2.11 which agrees well with the previous reported value of n=2.2. The sample surface measured by AFM is found to be sufficiently flat(the roughness of surface is estimated to be ∿ 2 nm.). The surface roughness increased to ∿ 20 nm after annealing of 800 ℃ for 1 hour. The Ta_2O_5 films with the thicknesses of 500 nm and 1 μm exhibited the transmission loss of ∿ -4.7 dB/cm at 633 nm measured by the prism - film coupler. The 2 μm width Ta_2O_5 optical waveguide having a sharp edge and a flat film surface was fabricated by the photo lithography micro procces.
