Resonant x-ray scattering method for measuring cation stoichiometry in BaSnO3 thin films

Epitaxial (Ba0.5Sr0.5) TiO3 thin films of two different thickness (∼25 and ∼134 nm) on MgO(001) prepared by a pulsed laser deposition method were studied by synchrotron x-ray scattering measurements. The film grew initially with a cube-on-cube relationship, maintaining it during further growth. As the film grew, the surface of the film became significantly rougher, but the interface between the film and the substrate did not. In the early stage of growth, the film was highly strained in a tetragonal structure (c/a = 1.04) with the longer axis parallel to the surface normal direction. As the growth proceeded further, it relaxed to a cubic structure with the lattice parameter near the bulk value, and the mosaic distribution improved significantly in both in- and out-of-plane directions. The thinner film (∼25 nm) showed only one domain limited mainly by the film thickness, but the thicker film (∼134 nm) exhibited three domains along the surface normal direction.

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A New X-Ray Scattering Method for Determining Pore-Size Distribution in Low-k Thin Films

MRS Proceedings ◽

10.1557/proc-714-l12.10.1 ◽

2001 ◽

Vol 714 ◽

Cited By ~ 1

Author(s):

Kazuhiko Omote ◽

Shigeru Kawamura

Keyword(s):

Thin Films ◽

Pore Size Distribution ◽

Pore Size ◽

Gas Adsorption ◽

Size Distributions ◽

X Ray ◽

X Ray Scattering ◽

Pore Size Distributions ◽

Scattering Technique ◽

Ray Scattering

ABSTRACTWe have successively developed a new x-ray scattering technique for a non-destructive determination of pore-size distributions in porous low-κ thin films formed on thick substrates. The pore size distribution in a film is derived from x-ray diffuse scattering data, which are measured using offset θ/2θ scans to avoid strong specular reflections from the film surface and its substrate. Γ-distribution mode for the pores in the film is used in the calculation. The average diameter and the dispersion parameter of the Γ-distribution function are varied and refined by computer so that the calculated scattering pattern best matches to the experimental pattern. The technique has been used to analyze porous methyl silsesquioxane (MSQ) films. The pore size distributions determined by the x-ray scattering technique agree with that of the commonly used gas adsorption technique. The x-ray technique has been also used successfully determine small pores less than one nanometer in diameter, which is well below the lowest limit of the gas adsorption technique.

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High-Resolution X-Ray Scattering from Thin Films and Multilayers

10.1007/bfb0109385 ◽

1999 ◽

Cited By ~ 3

Keyword(s):

Thin Films ◽

High Resolution ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

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Local Atomic Structures in Amorphous and Quasicrystalline Zr70Ni10Pt20and Zr80Pt20Alloys by the Anomalous X-ray Scattering Method

MRS Proceedings ◽

10.1557/proc-644-l1.1 ◽

2000 ◽

Vol 644 ◽

Cited By ~ 2

Author(s):

Eiichiro Matsubara ◽

Takahiro Nakamura ◽

Masaki Sakurai ◽

Muneyuki Imafuku ◽

Shigeo Sato ◽

...

Keyword(s):

Short Range ◽

Short Range Order ◽

Nearest Neighbor ◽

Scattering Method ◽

X Ray ◽

Coordination Numbers ◽

Atomic Structures ◽

X Ray Scattering ◽

Icosahedral Clusters ◽

Ray Scattering

AbstractLocal atomic structures around Zr and Pt in a quasicrystalline Zr80Pt20alloy, and amorphous and quasicrystalline Zr70Ni10Pt20alloys have been determined by the anomalous x-ray scattering (AXS) method. A distinct prepeak observed in an intensity profile of the amorphous Zr70Ni10Pt20alloy indicates existence of strong chemical short-range order (CSRO) clusters in the amorphous phase. Total coordination numbers around Zr and Pt in a nearest neighbor region in both alloys have been evaluated. The values around Pt are almost equal to 12 in the amorphous and quasicrystalline states suggest formation of icosahedral clusters around Pt. Some of crystalline structures formed from the quasicrystalline phases by annealing consist of icosahedral clusters of Zr and Ni atoms, or polyhedral clusters of Zr and Pt atoms similar with icosahedral clusters. The present result appears to support that the phase transformation from the amorphous to the crystal through the quasicrystal is explained by the icosahedral CSRO clusters in the amorphous and quasicrystalline states.

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