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Pt/Bi4Ti3O12(001)/Bi2SiO5(100)/Si(100) structures have been fabricated by the metalorganic chemical vapor deposition (MOCVD) at 500°. Bi2SiO5 film is used as a buffer layer to grow ferroelectric Bi4Ti3O12 films because of its relatively high dielectric constant (ε=30). The memory window has a C-V characteristic of about 0.8 V, and the retention time estimated by the zero-bias capacitance for the Pt/100-nm-Bi4Ti3O12/30-nm-Bi2SiO5/Si/Al structure is more than 11 days.

Bi4Ti3O12 thin films 100, 200 and 400 nm thick were prepared on Si(100) substrates using 30 nm Bi2SiO5 as a buffer layer, by metalorganic chemical vapor deposition (MOCVD). It was demonstrated that c-axis-oriented Bi4Ti3O12 films can be grown on Si substrates at 500°C using an a-axis-oriented Bi2SiO5 buffer layer. The dielectric constant of the Bi2SiO5 film was estimated to be about 30 from capacitance measurements. The capacitance-vs-voltage (C-V) characteristics of Pt/Bi4Ti3O12/Bi2SiO5/Si (MFIS) structures had ferroelectric switching properties, and the memory windows were about 0.8, 1.5 and 2.9 V for 100, 200 and 400 nm Bi4Ti3O12, respectively. Furthermore, it was shown that the capacitance at zero bias remains almost constant for 12 days. This suggests that Bi4Ti3O12/Bi2SiO5/Si MFIS structures have excellent memory retention properties.

Dynamics of the nonlocality measured by the violation of Svetlichny's Bell-type inequality is investigated in the non-Markovian model. The phenomenon of nonlocality sudden birth for the atoms and the reservoirs is obtained. The evolution of the nonlocality among the atoms or the reservoirs depends on the choice of the atom detuning from the cavity pseudomode, the cavity pseudomode decay and the rotation angles. For the small pseudomode decay in the near-resonance regime, the initial atomic nonlocality is completely transferred to the reservoirs ultimately.

We have developed a new low temperature growth technique for Bi4Ti3O12 thin films using a MOCVD method in which an ultra-thin double buffer layer (5-nm thick Bi4Ti3O12/5-nm thick TiO2) is used to control the crystallization and fine grain structure. The 100-nm thick Bi4Ti3O12 thin films fabricated at 400°C showed an extremely smooth surface morphology and good electrical properties, namely, a large remanent polarization of P r=11 µC/cm2, a coercive field of E c=90 kV/cm and a low leakage current I L=7×10-9 A/cm2 at 3 V. Moreover, we successfully fabricated 50-nm ultra thin Bi4Ti3O12 films with P r=9 µC/cm2 and E c=120 kV/cm at 3 V. For the first time, the fatigue free property, which is very important for nonvolatile ferroelectric memory (NVFRAM) applications, was confirmed up to 1×1012 switching cycles.