Papers by Keyword: BLT Thin Film

Abstract: We have investigated the structure and ferroelectric properties of the Bi_3.25La_0.75Ti₃O₁₂ (BLT) thin films on SiO₂/Si substrate fabricated by sol-gel method. We used the BLT films were annealed at various temperatures of 600, 650, and 700°C for one hour by conventional furnace annealing (CTA). The temperature dependence of leakage currents densities of ferroelectric BLT thin films. The crystalline structure of the prepared BLT thin films was analyzed by X-ray diffraction (XRD). Field emission scanning electron microscopy (FESEM) was used to observe the film thickness and the surface morphology including grain size and porosity. The leakage current density and capacitance of thin film were measured by HP4156C.

Abstract: Bi4Ti3O12 (BTO) and Bi3.25La0.75Ti3O12 (BLT) ferroelectric thin films were deposited on Pt/Si substrates by RF magnetron sputtering with Bi4Ti3O12 (BTO) and Bi3.25La0.75Ti3O12 (BLT) targets with 50-mm diameter and 5-mm thickness. The microstructure and ferroelectric properties of thin films were investigated. The grain growth behavior and ferroelectric properties such as remanent polarization were different in these two kinds of film, the effects of La doping in the BLT thin film were very obvious.

Abstract: Ferroelectric properties of Lead-free (Bi,La)4Ti3O12 (BLT) films were evaluated on the newly developed MTP (Merged Top-electrode and Plate-line) cell structure. The BLT film was deposited by pulsed-DC sputtering method on a buried Pt/IrOx/Ir bottom electrode stack with W-plug. The BLT composition in the sintered sputtering target was Bi4.8La1.0Ti3.0O12. However, the deposited film composition was about Bi4.0La1.0Ti3.0O12 after the heat treatment of crystallization at 700°C/O2/30sec. And grains of the BLT film were randomly oriented and uniformly small ellipsoidal shape (long direction: ~100nm, short direction: ~20 nm). The remnant polarization (2Pr) and the leakage current density measured in the 100nm-thick BLT film were about 21 C/cm2 and 3 ×10-5 A/cm2 at 3 V, respectively. The fatigue loss was about 10% of the initial polarization value after 1×1011 fatigue cycles.

Abstract: Bi4-xLaxTi3O12 (BLT) ferroelectric thin films were deposited on Pt/Si substrates by RF magnetron sputtering with Bi4-xLaxTi3O12 (x=0.5, 0.75, 1) targets with 50-mm diameter and 5-mm thickness. The effects of La contents on microstructure and ferroelectric properties of Bi4-xLaxTi3O12 thin films were investigated. The grain growth behavior and ferroelectric properties such as remanent polarization were found to be dependent on the La contents in the BLT thin films.