PHYSICAL INVESTIGATIONS OF NANOPHOTONIC LiNbO3 FILMS FOR PHOTONIC APPLICATIONS

The nanocrystalline structure of Lithium niobate (LiNbO3) was prepared and deposited onto substrate made of quartz by utilize pulse laser deposition technique. The effect of substrate temperature on the structural, optical and morphological properties of lithium niobate photonic film grown was studied. The chemical mixture was prepared by mixing the raw material (Li2CO3, Nb2O5) with Ethanol liquid without any further purification, at time of stirrer 3hrs but without heating, then annealing process the formed material at 1000C degrees for 4hrs. We characterized and analyzed the LiNbO3 nanostructure thin films by utilize Ultra-Violet Visible (UV-vis), X-Ray Diffraction (XRD) and Atomic Force Microscopy (AFM). The UV-vis measurements show that, when the substrate temperature increases, the values of transmission, absorption and energy band gap will decreased, but the values of reflection and refractive index will increased. While, the XRD measurements show that, the LiNbO3 structure will be more purity and crystalline with rising the substrate temperature, because the intensity of phase 2 theta( )at value of 34.8 degrees, 40.06 degrees and 48.48 degrees correspond to (110), (113) and (024) planes will be disappeared when the substrate temperature increases. Also, the AFM measurements show that, when the substrate temperature increased, the structure of film started to crystallization to be more homogeneous, smooth and uniform, while the surface roughness and grain size increased also with increase the substrate temperature. That means the LiNbO3 thin film prepared at substrate temperatures 300C degrees give the best result for manufacture the optical waveguide.