The Demonstration of High-Performance Multilayer BaTiO3/BiFeO3 Stack MIM Capacitors

Multilayer BaTiO
₃
/BiFeO
₃
(BTO/BFO) stack structures were prepared on the Pt/TiO
₂
/SiO
₂
/Si (100) substrate via highly accurate magnetron sputtering process. The cubic to the tetragonal phase transition of BTO was confirmed by both the X-ray diffraction and Raman spectroscopy after the process of rapid thermal anneal. An ~74.1% increase of the relative permittivity was observed with the increasing thickness of BFO in the metal-insulator-metal capacitor. On the other hand, we also demonstrate that the leakage current density and the relative permittivity are found to have 20-50 times reduction and 26.6% improvement, respectively, with the additional cap of the BTO layer.