LITHIUM-NIOBATE FILMS GROWN BY EXCIMER-LASER DEPOSITION

Laser ablation of single-crystal LiNbO3 targets is performed by means of an ArF laser. Films are grown onto glass, quartz and carbon-coated mica substrates held at room temperature. Amorphous and particulate-free films with the refractive index and optical energy gap close to those of bulk single-crystal LiNbO3 are obtained depending on the oxygen pressure applied during deposition and the laser fluence. Optical diagnostics of the laser induced plume show that the complex dynamics followed by lithium species in the gas phase are responsible for the variation of the film refractive index as a function of the laser fluence.