Composition controlling of KNbO3 thin films prepared by pulsed laser deposition

The composition of KNbO3 thin films prepared by pulsed laser deposition is crucially influenced by the deposition configuration. In the present study, the composition of KNbO3 thin films grown on Si (100) substrates by pulsed laser ablation was tried to be controlled by adjusting the target–substrate distance and the oblique angle of substrate from the plume axial direction. It was found that the K deficiency in the films can be effectively avoided by setting the substrate at an appropriate oblique angle from the plume axial direction. The stoichiometric KNbO3 thin films with a K/Nb molar ratio of 0.98 were successfully obtained, where the substrates were set at an oblique angle of 3–12° from the plume axis while the target–substrate distance was kept at 40 mm.