Ferroelectric Properties of SrRuO₃/(Ba, Sr)TiO₃/SrRuO₃ Epitaxial Capacitor

Abstract

Ferroelectric properties were investigated using SrRuO3/(Ba x , Sr1-x )TiO3(BSTO)/SrRuO3 all-perovskite heteroepitaxial capacitors on strontium titanate substrates. The dielectric film had a composition with a Ba content of x=0 to 1, i.e., the whole composition of the SrTiO3–BaTiO3 solid-solution system. The c-axis of the BSTO film was elongated depending on the Ba content, and reached 0.441 nm at the BaTiO3 composition, which was 8.6% larger than the bulk c-axis. A peak relative dielectric constant of 870 and maximum remanent polarization (2P r) of 58 µC/cm2 were obtained depending on the Ba content at a dielectric thickness of 20 nm. These are the highest storage capacitance capacitor and the thinnest ferroelectric capacitor reported so far. Possibilities for deep submicron ferroelectric and dielectric memory applications are also discussed.

On the Novel Biaxial Strain Relaxation Mechanism in Epitaxial Composition Graded La1−xSrxMnO3 Thin Film Synthesized by RF Magnetron Sputtering

“…Hussey and Gupta [26] reported a dual-beam, dual-target PLD method by using YBa2Oδ and CuO targets simultaneously for obtaining superconducting YBaCuO7−δ films. On the other hand, by using deposition by RF power co-sputtering, Kawakubo et al [27] achieved ECG BaxSr1−xTiO3 thin films with both SrTiO3 and BaTiO3 targets sputtered in various plasma power ratios. Compared to PLD, magnetron co-sputtering can provide a cost-effective, high-throughput and relatively low temperature process with large area scalability and co-sputtering capability and thus, it can be attractive for industry applications [20].…”

RF MAGNETRON SPUTTERING CONDITION DEPENDENCES OF DIELECTRIC NON-LINEARITY OF Ba0.6Sr0.4TiO3 THIN FILMS

“…Barium strontium titanate (Ba x Sr 1−x TiO 3 , short for BST) thin films are potential materials for the applications of microwave devices such as dielectric phase shifters and tunable filters due to their high dielectric nonlinearity, low leakage current, long lifetime, good temperature stability and adjusting Curie temperature [1][2][3][4][5][6][7][8]. In particular, dielectric nonlinearity is one of the most important factors for tunable microwave applications.…”

Pulsed laser operating on the first vibrational overtone of the CO molecule in the 2.5–4.2-μm range: 1. Multifrequency lasing

“…1) In addition, it has a good lattice matching and a thermal expansion coefficient similar to those of several functional oxide materials such as Pb(Zr,Ti)O 3 , 2-4) BiFeO 3 , 5,6) and (Ba,Sr)TiO 3 . 7,8) Generally, Pt has been widely used as an electrode for ferroelectric thin films. Nevertheless, it is well known that in ferroelectric thin films deposited on Pt bottom electrodes, the degradation of remanent polarization with switching polarization occurs.…”