[8a-N201-1~10] 6.1 Ferroelectric thin films

10:30 AM - 10:45 AM JST(1:30 AM - 1:45 AM UTC)English Presentation

[8a-N201-7] Effect of Ce doping on ferroelectric ZnO thin films: First principles calculation

〇SangHyo Kweon¹, Atsuhiro Tamai¹, Hideaki Adachi¹, Hiroki Moriwake², Ayako Taguchi², Isaku Kanno¹ (1.Kobe University, 2.JFCC)

Keywords:

ZnO,Ferroelectricity,First principles calculation

In our previous study, we substituted Ce and Mn to induce ferroelectricity in wurtzite-type ZnO thin films (Zn_1-x(Ce,Mn)_xO) grown on Pt/Ti/SiO₂/Si substrate. The c/a ratio decreased as the substitution x increased, likely due to the increased amount of Ce at Zn site. In this study, we explored the cause of the c/a ratio change resulting from Ce substitution using first-principles calculations with the VASP software. The calculation revealed that when Ce is substituted in its Ce⁴⁺ valence state, its coordination number changed from 4 (CeO₄ tetrahedron) to 5. This transition widens the basal plane of tetrahedra, reduces the c/a ratio, and finally facilitates the emergence of ferroelectricity.