Effect of postdeposition annealing on the structural and electrical properties of thin Dy₂TiO₅ dielectrics

This paper describes the effect of postdeposition annealing on the structural and electrical characteristics of high-k Dy₂TiO ₅ dielectric films deposited on Si (100) through reactive cosputtering. We used X-ray diffraction, X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and atomic force microscopy to investigate the structural and morphological features of these films after they had been subjected to annealing at different temperatures. The Dy₂TiO ₅ dielectrics annealed at 800 °C exhibited excellent electrical properties such as high capacitance value, small density of interface state, almost no hysteresis voltage, and low leakage current. This phenomenon is attributed to a rather well-crystallized Dy₂TiO₅ structure and the reduction of the interfacial layer at oxide/Si interface. This film also shows almost negligible charge trapping under high constant voltage stress.