Rf Magnetron Sputter-Deposition of La 0.5 Sr 0.5 CoO 3 //Pt Composite Electrodes for Pb(Zr, Ti)O 3 Thin Film Capacitors

La0.5Sr0.5CoO3 (LSCO) thin films have been deposited using RF magnetron sputterdeposition for use as an electrode material for Pb(Zr, Ti)O3 (PZT) thin film capacitors. The effect of the O2:Ar sputter gas ratio during deposition, on the LSCO film properties was investigated. It was found that the resistivity of the LSCO films deposited at ambient temperature decreases as the O2:Ar ratio was increased for both the as-deposited and annealed films. In addition, it was found that thin overlayers of LSCO tend to stabilize the underlying Pt//Ti electrode structure during subsequent thermal processing. The LSCO//Pt//Ti composite electrode stack has a low resistivity and provides excellent fatigue performance for PZT capacitors. Furthermore, the LSCO//Pt//Ti electrode sheet resistance does not degrade with annealing temperature and the electrode does not display hillock formation. Possible mechanisms for the stabilization of the Pt//Ti electrode with LSCO overlayers will be discussed.