| Autor: |
Sea-Fue Wang, Jinn P. Chu, W.Z. Chang, V. S. John, T.N. Lin, C.H. Wu |
| Rok vydání: |
2008 |
| Předmět: |
|
| Zdroj: |
Surface and Coatings Technology. 202:5448-5451 |
| ISSN: |
0257-8972 |
| DOI: |
10.1016/j.surfcoat.2008.06.112 |
| Popis: |
La-doped BaTiO3 thin films with 200 nm thickness were fabricated by r.f. magnetron sputtering system onto Pt/Ti/SiO2/Si substrates. The effects of post-annealing and the amount of dopant on microstructure and electrical properties were studied. The X-ray diffraction (XRD) study reveals that, the film becomes crystallized when the annealing temperature is above 550 °C. In addition, all the films show tetragonal BaTiO3 crystal structure without any second phase or reaction phase formation after annealed at 750 °C. The X-ray photoelectron spectroscopy (XPS) results provide the evidence to support the existence of La2O3 with excess of BaTiO3 structure, when the dopant content reaches more than 1.4 at.%. The dielectric constant also increases with increasing annealing temperature and it may be due to the better crystallinity and larger grain sizes. The 0.1 La film annealed at 750 °C shows a high dielectric constant of 487 measured at 1 MHz. The doped film in the as-deposited condition yields a reduction of leakage current was also observed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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