Characterization of ferroelectricity in metal/ferroelectric/insulator/semiconductor structure by pulsed C–V measurement; Ferroelectricity in YMnO3/Y2O3/Si structure

Ferroelectric properties of the metal/ferroelectric/insulator/semiconductor (MFIS) structure were investigated using the ${\mathrm{Pt/YMnO}}_3/{\mathrm{Y}}_2{\mathrm{O}}_3/\mathrm{Si}$ structure. The ferroelectric $\mathrm{C–V}$ hysteresis was observed for not only the ${\mathrm{Pt/YMnO}}_3(\mathrm{0001}){\mathrm{/Y}}_{\mathrm{2}}{\mathrm{O}}_{\mathrm{3}}\mathrm{/Si}$ capacitor but also the ${\mathrm{Pt/amorphousYMnO}}_{\mathrm{3}}{\mathrm{/Y}}_{\mathrm{2}}{\mathrm{O}}_{\mathrm{3}}\mathrm{/Si}$ capacitor. The polarization evaluated by conventional C–V measurement should include interfacial polarization and rearrangement of the space charge together with the spontaneous polarization by ferroelectricity. To eliminate the generation of the interfacial polarization and the rearrangement of the space charge, the shorter charging time should be used to evaluate the ferroelectricity of the MFIS capacitor. Therefore, we propose the pulsed C–V measurement as a new method for evaluating the MF(I)S capacitor.