Dielectric Properties of (Pb, La)TiO3 Thin Films by Multiple-Cathode Sputtering and Its Application to Dynamic Random Access Memory Capacitors

Abstract

(Pb, La)TiO3 (PLT) thin films were fabricated by multiple-cathode RF-magnetron sputtering. PLT films deposited on Pt/SiO2/Si at 460° C had a perovskite structure with preferred orientation in the (111) plane. The diffuse phase transition behavior was observed for the deposited PLT thin films. Thickness dependence and La content dependence of the electrical properties of the deposited PLT thin films are discussed. The dielectric constant and leakage current of the 100-nm-thick PLT(La/Ti=0.28) thin films were 396 and 10-7 A/cm2 (at a field of 500 kV/cm). These results indicate that the PLT thin films fabricated by multiple cathode RF magnetron sputtering are suitable for dynamic random access memory (DRAM) applications.