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Eur. Phys. J. Appl. Phys. 42, 95-98 (2008)
DOI: 10.1051/epjap:2008055
Influence of deposition parameters on the preferred orientation of BST thin films for UFPA applications
S.Z. Li1, Y.Q. Yang1, W.H. Huang2, T.J. Zhang2 and S.B. Wang11 College of Electronics and Information Engineering, Wuhan University of Science and Engineering, Wuhan 430073, P.R. China
2 Department of Materials Science and Engineering, Hubei University, Wuhan 430062, P.R. China
liszhan@yahoo.com.cn
(Received: 1 February 2007 / Received in final form: 8 December 2007 / Accepted: 22 January 2008 / Published online: 29 April 2008)
Abstract
Ba0.65Sr0.35TiO3 (BST) thin films have been deposited by
radio frequency magnetron sputtering. The effects of the deposition
parameters on the crystallization and microstructure of BST thin films were
investigated by X-ray diffraction and field emission scanning electron microscopy,
respectively. The crystallization behaviour of the films is clearly affected
by the substrate temperature, annealing temperature, and sputtering
pressure. The thin films that are deposited at room temperature are
amorphous in their as-deposited state. However, an improved crystallization
can be observed for BST thin films deposited at higher temperatures. As the
annealing temperature is increased, the dominant X-ray diffraction peaks
become sharper and more intense. The dominant diffraction peaks increase
with sputtering pressure, steadily increasing for films deposited from 0.37
to 1.2 Pa. When the sputtering pressure is increased up to 3.9 Pa, the films
have a (110) + (200) preferred orientation. Possible correlations between
the crystallization and the changes in the sputtering pressure are
discussed. SEM measurements indicate that the films, which consist of small
grains, are smooth and that the interface between the film and the substrate
is sharp and clear.
77.84.-s - Dielectric, piezoelectric, ferroelectric, and antiferroelectric materials.
68.55.-a - Thin film structure and morphology.
81.15.Cd - Deposition by sputtering.
© EDP Sciences 2008



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