High-resolution electron microscopy studies on coherent plate precipitates and nanocrystals formed by low-temperature heat treatments of amorphous Ti-rich Ti-Ni thin films

New structural planar defects in Ba-deficient Y1Ba2Cu3O7−δ (YBCO) (1:1.6:3) thin films grown on NdGaO3 and SrTiO3 substrates by metalorganic chemical vapor deposition have been observed by means of high-resolution electron microscopy. The defects are associated with perturbations of the YBCO “1:2:3” stacking sequences along the c direction, which give rise to structural variants with locally “2:5:7,” “3:4:7,” or “4:6:10” cationic stoichiometries. The defects can be consistently interpreted as CuO–YO–CuO/CuO conversions or YO/BaO (BaO/YO) interconversions in the (a,b) planes and extending over a few nanometers along the c axis. Structural models based on image matching with simulations are proposed for two particular cases. It is thought that these structural imperfections can be effective sites of flux pinning.

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High-resolution electron microscopy investigations on stacking faults in SrBi2Ta2O9 ferroelectric thin films

Applied Physics Letters ◽

10.1063/1.1332106 ◽

2001 ◽

Vol 78 (7) ◽

pp. 973-975 ◽

Cited By ~ 13

Author(s):

X. H. Zhu ◽

A. D. Li ◽

D. Wu ◽

T. Zhu ◽

Z. G. Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

High Resolution ◽

Stacking Faults ◽

High Resolution Electron Microscopy ◽

Ferroelectric Thin Films ◽

Resolution Electron

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Study of the growth mechanism of highly in-plane aligned α-axis YBa2Cu3O7−x thin films on LaSrGaO4 substrate by high resolution electron microscopy

Journal of Materials Research ◽

10.1557/jmr.1996.0372 ◽

1996 ◽

Vol 11 (12) ◽

pp. 2951-2954 ◽

Cited By ~ 1

Author(s):

J. G. Wen ◽

S. Mahajan ◽

H. Ohtsuka ◽

T. Morishita ◽

N. Koshizuka

Keyword(s):

Thin Film ◽

Electron Microscopy ◽

Thin Films ◽

High Resolution ◽

High Resolution Electron Microscopy ◽

Cross Sectional ◽

Plan View ◽

Oriented Film ◽

Resolution Electron ◽

Average Size

Highly in-plane aligned α-axis YBa2Cu3O7−x thin films deposited on (100) LaSrGaO4 substrates by a self-template method were studied by high-resolution electron microscopy along three orthogonal 〈100〉 axes of the substrate. Plan-view images confirm that the majority of the film preferentially aligns across the entire substrate except for very few misaligned domains with average size 10 nm2. Cross-sectional images along the [100] orientation of YBa2Cu3O7−x reveal that in-plane aligned α-axis YBa2Cu3O7−x is grown on a template layer dominated by c-axis oriented film. This strongly suggests that the in-plane alignment of α-axis YBa2Cu3O7−x thin films on (100) LaSrGaO4 substrates is governed by the different stresses along the b and c axes of the substrate. Cross-sectional images along [001] of the YBa2Cu3O7—x thin film reveal that the 90° domains easily nucleate in the region between α-axis YBa2Cu3O7—x and the YBa4Cu3Ox phase. Cracks along the (001) plane of YBa2Cu3O7−x are found to be due to the large mismatch between the c parameters of the thin film and substrate.

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