Effect of laser fluence on c‐axis orientation of LiNbO3 piezoelectric films on nanocrystalline diamond by pulsed laser deposition

Completely c-axis oriented LiNbO3 piezoelectric films have been deposited on nanocrystalline diamond (NCD)/Si substrates with SiO2 buffer layer by pulsed laser deposition. The amorphous SiO2 buffer layer was formed on NCD/Si substrates by sol-gel method. The c-axis orientation and crystallinity of LiNbO3 films are strongly dependent on the laser fluence, and the laser fluence 3.6 J/cm2 is found to be the optimal value for the growth of oriented LiNbO3 film, which has a smooth surface with composed of a large mount of uniform grains. The average surface roughness of LiNbO3 films is about 6.7 nm.