Applied Physics Letters · 1992 · 58 citations · 8 references
Natural SciencesMaterials EngineeringMaterials ScienceElectronic MaterialsSemiconductor MaterialsThin FilmsDielectricsElectrode MaterialsMemory DevicesPerovskite MaterialsThin Film Electrical PropertiesThin-film MaterialsCapacitorsCharge StorageCurrent DensityDynamic Random-access MemoryLeakage CurrentPlatinum ElectrodesSol-gel ProcessingX-ray Diffraction Analysis
Paraelectric lead lanthanum zirconium titanate (PLZT) films, 150 nm thick, were deposited using a spin-coat, sol-gel process followed by a 650 °C oxygen anneal. X-ray diffraction indicated complete conversion to the perovskite phase. Sputter-deposited platinum electrodes were employed with the PLZT films to form thin-film capacitors with the best combination of high charge storage density (26.1 μC/cm2 at 3 V and 36.4 μC/cm2 at 5 V) and leakage current density (0.2 μA/cm2 at 3 V and 0.5 μA/cm2 at 5 V ) reported to date. The electrical characteristics of these thin-film capacitors meet the requirements for a planar bit cell capacitor for 64-Mbit dynamic random access memories.
8