BaTiO sub(3) based relaxor ferroelectric epitaxial thin-films for high-temperature operational capacitors

• Published in: Japanese Journal of Applied Physics Vol. 54; no. 4S; pp. 04DH02 - 1-04DH02-4
• Main Authors: Kumaragurubaran, Somu, Nagata, Takahiro, Takahashi, Kenichiro, Ri, Sung-Gi, Tsunekawa, Yoshifumi, Suzuki, Setsu, Chikyow, Toyohiro
• Format: Journal Article
• Language: English
• Published: 01.04.2015
• Subjects: Annealing; Capacitors; Defect annealing; Dielectric constant; Ferroelectric materials; Ferroelectricity; Power semiconductor devices; Relaxors; Thin films
• ISSN: 0021-4922; 1347-4065
• DOI: 10.7567/JJAP.54.04DH02

The epitaxial growth of 0.6[BaTiO sub(3)]-0.4[Bi(Mg sub(2/3) Nb sub(1/3))O sub(3)] (BT-BMN) relaxor ferroelectric thin-films on (100) Nb doped SrTiO sub(3) substrates has been achieved and the structure is investigated for high-temperature capacitor applications. The post growth annealing decreases the oxygen vacancy and other defects in BT-BMN films, resulting in the enhancement of dielectric constant. An insertion of intermediate SrRuO sub(3) layers as an electrode instead of Pt, sandwiching the film, is found to be more effective in enhancing the dielectric constant. A very high dielectric constant exceeding 400 was achieved from high-temperature annealed film and the film showed an excellent dielectric constant stability of below 11% in the temperature range of 80-400 [degrees]C. This will enable smaller, high-temperature tolerant, monolithically integrated thin-film capacitors on power semiconductor devices.