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Title: Sn-modified BaTiO 3 thin film with enhanced polarization
Hybrid molecular beam epitaxy (MBE) growth of Sn-modified BaTiO 3 films was realized with varying domain structures and crystal symmetries across the entire composition space. Macroscopic and microscopic structures and the crystal symmetry of these thin films were determined using a combination of optical second harmonic generation (SHG) polarimetry and scanning transmission electron microscopy (STEM). SHG polarimetry revealed a variation in the global crystal symmetry of the films from tetragonal ( P4 mm) to cubic [Formula: see text] across the composition range, x = 0 to 1 in BaTi 1− x Sn x O 3 (BTSO). STEM imaging shows that the long-range polar order observed when the Sn content is low ( x = 0.09) transformed to a short-range polar order as the Sn content increased ( x = 0.48). Consistent with atomic displacement measurements from STEM, the largest polarization was obtained at the lowest Sn content of x = 0.09 in Sn-modified BaTiO 3 as determined by SHG. These results agree with recent bulk ceramic reports and further identify this material system as a potential replacement for Pb-containing relaxor-based thin film devices.  more » « less
Award ID(s):
1851987 2011401
PAR ID:
10406248
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
41
Issue:
2
ISSN:
0734-2101
Page Range / eLocation ID:
022701
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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