Effect of yttria-stabilized zirconia thickness on crystal structure and electric property of epitaxial CeO2/yttria-stabilized zirconia buffer layer in metal/ferroelectric/insulator/semiconductor structure

The effect of yttria-stabilized zirconia (YSZ) film thickness on crystal st ructure and electric properties of epitaxial CeO2/YSZ films was investigate d. The CeO2/YSZ films were prepared on Si(001) substrates by pulsed laser d eposition (PLD). X-ray diffraction measurements and reflection high energy electron diffraction (RHEED) observation indicated that heteroepitaxial gro wths of CeO2 and YSZ were achieved with a cube on-cube relation (CeO2[100] parallel to YSZ[100] parallel to Si[100]) regardless of the YSZ film thickn ess. Measurement of C-V characteristics :showed ion drift; this: ion drift decreased with the decrease of YSZ film thickness. Measurement of I-V chara cteristics indicated that the leakage-current for all films was low enough for the insulating layer in the metal/ferroelectric/insulator/semiconductor (MFIS) structure, however for the films with a thicker YSZ layer, a differ ence in current was observed at various measurement positions. The rear;on for this was ascribed to the differences in the microstructure.