A Comparative Study on the Ferroelectric Performances in Atomic Layer Deposited Hf0.5Zr0.5O2 Thin Films Using Tetrakis(ethylmethylamino) and Tetrakis(dimethylamino) Precursors
Baek Su Kim, Seung Dam Hyun, Taehwan Moon, Keum Do Kim, Young Hwan Lee, Hyeon Woo Park, Yong Bin Lee, Jangho Roh, Beom Yong Kim, Ho Hyun Kim, Min Hyuk Park, Cheol Seong Hwang
Abstract
Abstract The chemical, physical, and electrical properties of the atomic layer deposited Hf 0.5 Zr 0.5 O 2 thin films using tetrakis(ethylmethylamino) (TEMA) and tetrakis(dimethylamino) (TDMA) precursors are compared. The ligand of the metal-organic precursors strongly affects the residual C concentration, grain size, and the resulting ferroelectric properties. Depositing Hf 0.5 Zr 0.5 O 2 films with the TDMA precursors results in lower C concentration and slightly larger grain size. These findings are beneficial to grow more ferroelectric-phase-dominant film, which mitigates its wake-up effect. From the wake-up test of the TDMA-Hf 0.5 Zr 0.5 O 2 film with a 2.8 MV/cm cycling field, the adverse wake-up effect was well suppressed up to 10 5 cycles, with a reasonably high double remanent polarization value of ~40 μC/cm 2 . The film also showed reliable switching up to 10 9 cycles with the 2.5 MV/cm cycling field without involving the wake-up effect but with the typical fatigue behavior.