Physical and electrical properties of nanolaminated HfO 2/ LaAlO 3HfO 2 dielectric on Si

Abstract

Because of high defectivity and poor uniformity in polycrystalline Hf O2, searching for an amorphous dielectric with a high dielectric constant and good stability has become an increasingly important task for high- k gate-stack research. We show that nanolaminated Hf O2 LaAl O3 Hf O2 dielectric grown on Si not only remains amorphous after annealing in N2 at 900°C for 60 s but also has an effective dielectric constant comparable to that of Hf O2. Additionally, electrical characterization of the capacitors made from the laminated dielectric revealed a smaller hysteresis and improved voltage stress behavior compared to its polycrystalline Hf O2 counterpart. © 2006 American Institute of Physics.