PULSED-LASER DEPOSITION OF ELECTROCERAMIC THIN-FILMS

Sintered targets of BaTiO3 are ablated by KrF excimer laser radiation (lambda(L) = 248 nm) with pulsed-laser deposition (PLD) in order to pr oduce electroceramic thin films for dielectric and ferroelectric appli cations. Plasma formation and expansion is observed by a time-of-fligh t (TOF) setup with time-resolved (10 ns resolution) plasma emission sp ectroscopy (PES) in the 200 to 900 nm wave length range. Thin films wi th tetragonal crystalline structure and a dielectric constant up to 79 0 are deposited on Si(111)/Ti/Pt substrates. Ellipsometry is used to d etermine the influence of the laser cross-section geometry on the targ et surface on the film thickness homogeneity. The influence of beam pa rameters on particle speed in the plasma and on the electrical and str uctural properties of deposited films is presented. The chemical compo sition of the thin films as a function of processing variables is char acterized by X-ray photoelectron spectroscopy (XPS). Crystalline struc ture is analysed by Raman-microprobe spectroscopy (RMP) and X-ray diff raction (XRD). Electrical characterisation is done by impedance measur ements.