Impact of Al-Doping on Ferroelectricity and Reliability of HfZrO Film Under High Temperature Annealing

This study explores the influences of Al-doping on a ferroelectricity and a reliability of Hf ${}_{{0}.{5}}$ Zr ${}_{{0}.{5}}$ O2 (HZO) films with a high temperature annealing. The Al-doped HZO (Al:HZO) films, in which the Al2O3 (AlO) layers are uniformly doped into the HZO films, are fabricated by using the super-cycles of atomic layer deposition (ALD). All the Al:HZO films show the reduced leakage current, increased breakdown field, 10-year lifetime voltage (> 2.32 V), endurance (> $10^{{10}}$ cycles) without observable fatigue and wake-up effect. Among the Al:HZO films, the 72:1 cycle ratio (CR) exhibits the highest remanent polarization ( ${P}_{\text {r}}\text {)}$ of $\boldsymbol {\sim } 22.7~\boldsymbol {\mu }$ C/cm2, while the 36:1 CR offered an optimal trade-off between reliability and ${P}_{\text {r}}$ ( $\boldsymbol {\sim } 19.1~\boldsymbol {\mu }$ C/cm ${}^{{2}}\text {)}$ . These results suggest that the Al:HZO films are promising candidates for the next-generation 3D ferroelectric memory applications requiring high thermal budget compatibility and robust reliability.