Positive Effect of Parasitic Monoclinic Phase of Hf0.5Zr0.5O2 on Ferroelectric Endurance

Endurance of ferroelectric HfO2 needs to be enhanced for its use in commercial memories. This work investigates fatigue in epitaxial Hf0.5Zr0.5O2 (HZO) instead of polycrystalline samples. Using different substrates, the relative amount of orthorhombic (ferroelectric) and monoclinic (paraelectric) ph...

Descripción completa

Detalles Bibliográficos
Autores: Song, Tingfeng, Estandía, Saúl, Tan, Huan, Dix, Nico, Gázquez, Jaume, Fina, Ignasi, Sánchez Barrera, Florencio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/250859
Acceso en línea:http://hdl.handle.net/10261/250859
Access Level:acceso abierto
Palabra clave:Epitaxial oxide
Ferroelectric endurance
Ferroelectric hafnium oxide
Descripción
Sumario:Endurance of ferroelectric HfO2 needs to be enhanced for its use in commercial memories. This work investigates fatigue in epitaxial Hf0.5Zr0.5O2 (HZO) instead of polycrystalline samples. Using different substrates, the relative amount of orthorhombic (ferroelectric) and monoclinic (paraelectric) phases is controlled. Epitaxial HZO films almost free of parasitic monoclinic phase suffer severe fatigue. In contrast, fatigue is mitigated in films with a greater amount of paraelectric phase. This suggests that fatigue can be intrinsically pronounced in ferroelectric HZO. It is argued that the enhancement of endurance in films showing coexisting phases results from the suppression of pinned domain propagation at ferroelectric–paraelectric grain boundaries, in contrast with a rapid increase of the size of the pinned domains in single ferroelectric regions.