Pulsed-laser deposition of barium titanate films and plume dynamics

Barium titanate BaTiO3.thin films were fabricated by the pulsed-laser deposition PLD.technique. The temporal changes of ablated barium Ba. and titanium Ti. atoms in the gas phase during PLD process were monitored by imaging laser-induced fluorescence LIF.technique. The expansion of the plume was influenced by the presence of a hot substrate as well as the pressure of an ambient oxygen gas. The quality of deposited films were characterized by X-ray diffraction XRD. method, scanning electron microscope SEM.and in-situ optical second harmonic generation SHG.. A smooth surface was obtained when the film was deposited at 10 mTorr. The lattice parameter was shortened, as the ambient oxygen gas pressure was increased. q1998 Elsevier Science B.V.