Cho, K. H. Ha, J. Y. Choi, J. W. Kim, J. S. Yoon, S. J. Kang, C. Y. Lee, Y. P. 2024-01-21T02:33:30Z 2024-01-21T02:33:30Z 2021-08-31 2006-09 0374-4884 https://pubs.kist.re.kr/handle/201004/135221 Ferroelectric (Ba0.5Sr0.5)TiO3 (BST) thin films with thicknesses of 500 nm were deposited on LaAlO3 (LAO) substrates by RF magnetron sputtering at 800 degrees C. The BST films were characterized for structure by using X-ray diffraction (XRD). The surface morphologes and the thicknesses of BST films were characterized by using atomic force microscopy (AFM) and field-emission scanning electron microscope (FESEM), respectively. We measured the dielectric properties at microwave frequencies (1 - 3 GHz) by using a symmetrical stripline resonator with shorted ends at room temperature. The tunability of the as-deposited and the annealed BST films were 1 % and 27 % at a field of 40 kV/mm and values of tan delta of 0.0038 and 0.0050, respectively. Through a post-annealing process, we were able to improve the dielectric constant and tunability, although the dielectric loss was slightly increased. The change in the dielectric properties after annealing could be attributed to a change in the film strain. English KOREAN PHYSICAL SOC DIELECTRIC-PROPERTIES GROWTH Characteristics of (Ba,Sr)TiO3 thin films for microwave tunable device applications Article 1 JOURNAL OF THE KOREAN PHYSICAL SOCIETY, v.49, no.3, pp.1076 - 1080 JOURNAL OF THE KOREAN PHYSICAL SOCIETY 49 3 1076 1080 scie scopus kci ART001025051 000240570400049 2-s2.0-33749824446 Physics, Multidisciplinary Physics Article DIELECTRIC-PROPERTIES GROWTH ferroelectric film dielectric properties BaSrTiO3 tunable microwave device