Characteristics of metal-ferroelectric-insulator-semiconductor diodes composed of Pt electrodes and epitaxial Sr_(0.8)Bi_(2.2)Ta_2O_9(001 )/SrTiO_3(100)/Si(100) structures

摘要

Epitaxial metal-ferroelectric-insulator-semiconductor diodes were fabricated by depositing a chemical-solution-decomposed Sr_(0.8)Bi_(2.2)Ta_2O_9 (SBT) film on an SrTiO_3-coated Si(100) wafer. X-ray diffraction analysis revealed that the SBT film was composed mostly of oaxis-oriented grains. In Pt/SBT(300 nm)/SrTiO_3(23 nm)/Si diodes, a memory window as wide as 1.1 V was obtained for a voltage sweep of ±7 V in capacitance-voltage measurement. The capacitance change in per decade increase in the retention time was approximately 10% up to 24 h. The origin of the ferroelectricity in a c-axis-oriented SBT film is discussed.