Effects Of Water Vapour On TiO 2 ,LiNb 3 O 8 AND (TixNb1_x)O 2 Compound Kinetics During Ti:LiNbO 3 Waveguide Fabrication

The knowledge of the Ti:LiNb03 waveguide formation mechanism is required to understand the factors influencing the waveguide optical characteristics, performances, quality and reliability. Despite the increasing importance of the Ti:LiNbO3 waveguides in the development of hybrid integrated optical devices, the Ti indiffusion process is not still completely understood. This paper reports the results of a study on the different compounds which form during the process which leads to the Ti diffusion in LiNbO3 and on the effect of Lle presence of water vapours on their growth kinetics. Ti indiffusion process on Z- and Y- cut substrates and in different (dry and wet) atmospheres was investigated by many microanalytical techniques. Some correlations between the structural and optical characteristics of the waveguides are also reported.