High-Frequency response in ferroelectric BaSrTiO3 thin films studied by terahertz time-domain spectroscopy
Language
en
Article de revue
This item was published in
Japanese Journal of Applied Physics, part 1 : Regular papers, Short Notes. 2005, vol. 44, n° 7A, p. p. 5058-5061
English Abstract
We have measured the dielectric properties of BaTiO3–SrTiO3 thin films, deposited on fused silica substrates, in the MHz and THz frequency regions. Different experimental Chemical Vapor Deposition parameters were analyzed ...Read more >
We have measured the dielectric properties of BaTiO3–SrTiO3 thin films, deposited on fused silica substrates, in the MHz and THz frequency regions. Different experimental Chemical Vapor Deposition parameters were analyzed to improve dielectric properties of these thin films. In particular, we clarify pressure and oxygen percentages during the deposition of the thin layer. The complex permittivity function of the film was accurately determined between 100 GHz and 1 THz. We show that the real part of the dielectric behavior at very high frequencies follows the same tendency of the low frequency dielectric behavior also measured. These results are correlated to X-ray diffraction and RBS patterns, which show that the cationic ratio (Ba+Sr)/Ti increases from about 0.6 to 0.9 as sputtering pressure changes from 1 to 5 Pa, leading to better dielectric properties.Read less <
English Keywords
Far-infrared spectroscopy
Ferroelectrics
Thin Films
BaTiO3
SrTiO3
Inorganic compounds
X-ray diffraction
Dielectrics
High frequency
Origin
Hal imported