Effects of heat treatment and in situ high-temperature X-ray diffraction study on the formation of ferroelectric epitaxial Y-doped HfO2 film

• DOI: 10.7567/1347-4065/aafed1
• Publication Date: 2019-02-25T20:13:36Z
• Authors: Takanori Mimura; Takao Shimizu; Takanori Kiguchi; Akihiro Akama; Toyohiko J. Konno; Yoshio Katsuya; Osami Sakata; Hiroshi Funakubo
• Keywords: Orthorhombic crystal system; Monoclinic crystal system; Tetragonal crystal system; Pulsed Laser Deposition

The process of forming the ferroelectric orthorhombic phase was investigated for epitaxial 7% Y-doped (YHO7) films using in situ high-temperature X-ray diffraction. Epitaxial YHO7 were grown on (111) ITO-coated (111)YSZ substrates by pulsed laser deposition at room temperature and a subsequent heat treatment process. Films deposited crystallized as paraelectric monoclinic phase. partially changes to tetragonal above 600 °C perfectly transformed around 950 during heating. change from detected 300 °C, corresponding Curie under cooling These results clearly suggest that more stable 1000 heating than other phases, formation this phase—the phase—is key