Characteristics of metal-ferroelectric-insulator-silicon structures with ferroelectric (Pb0.8Ba0.2)ZrO3 thin films and (Ba0.5Sr0.5)TiO3 buffer layer

Abstract

The results of the fabrication and characterization of ferroelectric (Pb0.8Ba0.2)ZrO3 (PBZ) thin films grown on nitrided silicon substrates with a (Ba0.5Sr0.5)TiO3 (BST) buffer layer by the rf-magnetron sputtering technique are reported. The PBZ thin films were used as the ferroelectric layer in the ferroelectric field effect transistors. The PBZ thin films were grown with highly (100) preferred orientation on BST buffer layers. The Auger electron spectroscopy depth profiles showed no significant interdiffusion between the PBZ and silicon components. The capacitance-voltage properties of Pt/PBZ (360nm)∕BST (30nm)∕Si structures demonstrated ferroelectric switching effect. The memory windows were about 0.6, 1.25, and 1.76V, respectively, for sweeping bias of ±3, ±4, and ±5V. The leakage current density was below 1×10−8A∕cm2 at ±4V.