화학공학소재연구정보센터
Korean Journal of Chemical Engineering, Vol.15, No.1, 85-89, January, 1998
THE INFLUENCE OF CHEMICAL PASSIVATION ON THE PZT/Pt ELECTRODE INTERFACE
It has been recognized that the interdiffusion of atomic species between a PZT film and the Pt bottom electrode leads to the gradual degradation of a PZT capacitor. In order to prevent this interdiffusion, experimental studies on chemical passivation to the bottom electrode surface were carried out by the sulfurization method. It was observed that a sulfur layer was built up on the Pt substrate with small grains, which resulted in a structural change at the Pt surface. Atomic force microscopy (AFM) showed that the film roughness of the Pt surface was increased by sulfur treatment. Pb(Zr0.5Ti0.5)O3(PZT) thin films were prepared on a Pt/Ti/SiO2/Si bottom electrode by spin-coating techniques. The microstructure and the preferred orientation of the PZT films were shown to depend on the sulfurtreated electrode. The PZT capacitor on a clean Pt electrode was confirmed to be ferroelectric with Pr=17.7 μC/㎠ and Ec=65 kV/cm from the P-E hysteresis curves. The fatigue behavior of a PZT film capacitor prepared on a sulfurtreated one was observed to be relaxed, but the absolute value of Pr was paid off.
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