Abstract
Titanium diffused LiNbO3 crystals are widely used in integrated optics. This paper reports the observations of the LiNbO3 crystal surface under the diffusion of Ti. At the first stage of the diffusion process, Ti diffusion areas swelled up to about 3 times that of the initial metal Ti film thickness, and the surface roughness increases. On the progress of diffusion, the height and roughness of the Ti diffusion area decrease; finally the height becomes 1.5-2 times as small as that of the initial metal Ti thickness, and the surface roughness becomes as small as the initial condition. After the diffusion time calculated based on the experimental diffusion coefficie, the crystal surface becomes smooth.
