A Study on the Hf0.5Zr0.5O2 Ferroelectric Capacitors fabricated with Hf and Zr Chlorides

Ferroelectric capacitor memory devices with carbon-free Hf 0.5 Zr 0.5 O 2 (HZO) ferroelectric films are fabricated and characterized. The HZO ferroelectric films are deposited by ALD at temperatures from 225 to 300°C, with HfCl 4 and ZrCl 4 as the precursors. Residual chlorine from the precursors is measured and studied systematically with various process temperatures. 10nm HZO films with optimal ALD growth temperature at 275°C exhibit remanent polarization of 25µC/cm2 and cycle endurance of ~ 5×10 ¹¹ . Results will be compared with those from HZO films deposited with carbon containing metal-organic precursors.