Effects of rare earth metal (Gd and Dy) doping on the structural and electrical properties of K0.5Bi4.5Ti4O15 thin films. Issue 10 (December 2015)

• Record Type: Journal Article
• Authors: Raghavan, Chinnambedu Murugesan; Kim, Jin Won; Choi, Ji Ya; Song, Tae Kwon; Kim, Sang Su
• Is Part Of: Ceramics international. Volume 41:Issue 10(2015)Part B
• Page Start: 15138
• Page End: 15144
• Publication Date: 2015-12
• Subjects: A. Films -- A. Sol–gel processes -- C. Electrical properties -- C. Ferroelectric properties; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.08.086
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: K0.5 Bi4.5 Ti4 O15 (KBTi), K0.5 Bi4 Gd0.5 Ti4 O15 (KBGdTi), and K0.5 Bi4 Dy0.5 Ti4 O15 (KBDyTi) thin films were prepared on Pt(111)/Ti/SiO2 /Si(100) substrates by using a chemical solution deposition method to investigate the effects of doping on the structural, electrical, and ferroelectric properties. Doping with Gd- and Dy-ions clearly leads to notable improvements in the electrical and ferroelectric properties. Among the thin films, the KBGdTi thin film exhibited a low leakage current density of 1.83×10 –9 A/cm 2 at 100 kV/cm, a large ferroelectric polarization of 49 μC/cm 2, and a low coercive electric field of 398 kV/cm at an applied electric field of 885 kV/cm. A fatigue endurance study showed that the switchable polarization was reduced by only 4% of the initial value after 1.44×10 10 switching cycles for the Gd- and Dy-doped KBTi thin films. The improvements in electrical and ferroelectric properties of the Gd- and Dy-doped KBTi thin films were explained on the basis of microstructural change, a decrease in the number of oxygen vacancies, and structural distortion caused by doping with Gd- and Dy-ions.