Crystal and electrical characterizations of oriented yttria-stabilized zirconia buffer layer for the metal/ferroelectric/insulator/semiconductor field-effect transistor

Using reflection high-energy electron diffraction (RHEED), X-ray diffraction (XRD) and X-ray pole figure measurements, we evaluated the crystallinities of yttria-stabilized zirconia (YSZ) thin films as an intermediate layer for metal/ferroelectric/insulator/semiconductor-structure field-effect transistors (MFIS-FETs). A highly oriented YSZ film was grown on a Si(100) substrate by the vacuum evaporation method. The [100] axes of the YSZ crystals were aligned parallel to [100] axes of Si crystals in the plane. In addition, electrical characterizations of the highly oriented YSZ thin films on Si(100) were evaluated from current-voltage (I-V) and capacitance-voltage (C-V) measurements. The I-V measurement indicated a breakdown field of about 3 MV/cm (at I = 1 nA/cm(2)). The C-V measurement results suggest that mobile ions were present in the YSZ films. Oriented perovskite PbTiO3 films were deposited on YSZ crystal and YSZ/Si(100) substrates by the digital chemical vapor deposition (CVD) method. These PbTiO3 films included many PbTiO3 grains with their [100] axes parallel to the [100] or [110] axis of YSZ crystals in the plane of the PbTiO3/YSZ interface.