抄録
5 mol% MgO doped LiNbO_3 thin film optical waveguides were fabricated by liquid phase epitaxy on Z-cut LiTaO_3 substrates using Li_2O-V_2O_5 and Li_2O-B_2O_3 flux systems to investigate a dependence of optical proper-ties on melt composition. Lattice mismatches between LiNbO_3 thin film and LiTaO_3 substrate were measured 5.5×10^<-3> A by X-ray powder deffractometer. Na was add-ed to the flux system to achive lattice matching. 5 mol% MgO doped LiNbO_3 thin films with good surface morpholgy, high crystallinity, nearly stoichiometric singl crystal and single frerroelectric domain were grown on Z-cut LITaO_3 substrates by a flat one-side dipping LPE method. The optical waveguide had a step index for the ordinary and the extraordinary waves. Using Li_2O-B_2O_3 flux system, the optical waveguide with high optical damage resistance and low optical absorption at visible wavelength was obtained.
