Preparation and Properties of Ferroelectric–Insulator–Semiconductor Junctions Using YMnO₃ Thin Films

Abstract

On the basis of consideration of the design of materials for MFIS-FETs, the application of YMnO₃ and Y₂O₃ films as the ferroelectric and insulator layers, respectively, is proposed. After process optimization for the YMnO₃ and Y₂O₃ films, an YMnO₃/Y₂O₃ capacitor with an epitaxial structure was developed. The use of epitaxial films drastically improves the dielectric and ferroelectric characteristics, and a relatively long memory retention time exceeding 10⁴ s was successfully obtained. A relationship between memory retention and the polarization state or leakage current is proposed.