Synchrotron x-ray Scattering Study on Oxidation of AIN/Sapphire

ABSTRACTWe present an x-ray scattering study of the oxidation of AIN/sapphire films into λ-A12O3 upon annealing. Epitaxial AIN/Sapphire(0001) transforms into nano-crystalline epitaxial λ-A12O3 during annealing at temperatures above 800°C in air. The crystalline orientational relation between the λ-Al2O3 and AIN are < 111 > // < 0001 > in the film normal direction, and < 110 > // < 1120 > in the film plane direction. The domain size of the spinel λ-A1203 crystalline is smaller than 50 Å in both out-of-plane and in-plane directions. The XPS depth profiles of the oxide film showed that the film is composed of aluminum and oxygen, and the atomic concentration ratio is about 2:3.

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Lattice Relaxation of Eras/Gaas: An X-Ray Scattering Study

MRS Proceedings ◽

10.1557/proc-202-579 ◽

1990 ◽

Vol 202 ◽

Cited By ~ 1

Author(s):

P. F. Miceli ◽

K. W. Moyers ◽

C. J. Palmstrøm

Keyword(s):

Lattice Relaxation ◽

Epitaxial Layers ◽

Misfit Dislocations ◽

X Ray ◽

X Ray Scattering ◽

Ideal System ◽

Out Of Plane ◽

Scattering Study ◽

Interference Oscillations ◽

Ray Scattering

ABSTRACTThe results of a high resolution x-ray scattering study of [001]ErAs epitaxial layers grown on [001]GaAs is presented. ErAs is pseudomorphic on GaAs for thicknesses below 70Å and, for thicker films, lattice relaxation is oberved concomitant with an Increase of the In-plane mosaic due to the formation of misfit dislocations. Above 300Å, the out-of-plane transverse scattering from the ErAs lattice planes Is no longer specular and further relaxation Is related to the out-of-plane mosaic. The ratio of elastic constants, C12/C11, Is determined to be 0.126 and the thermal expansion was measured. Thin film Interference oscillations are observed and modeled. ErAs/GaAs Is an Ideal system for x-ray scattering studies of lattice relaxation and structure in epitaxial layers. Films as thin as 20Å have been studied.

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Uncovering the out-of-plane nanomorphology of organic photovoltaic bulk heterojunction by GTSAXS

Nature Communications ◽

10.1038/s41467-021-26510-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xinxin Xia ◽

Tsz-Ki Lau ◽

Xuyun Guo ◽

Yuhao Li ◽

Minchao Qin ◽

...

Keyword(s):

Active Layer ◽

Model Systems ◽

Fullerene Derivative ◽

Grand Challenge ◽

Device Performance ◽

X Ray ◽

X Ray Scattering ◽

Out Of Plane ◽

Plane Direction ◽

Ray Scattering

AbstractThe bulk morphology of the active layer of organic solar cells (OSCs) is known to be crucial to the device performance. The thin film device structure breaks the symmetry into the in-plane direction and out-of-plane direction with respect to the substrate, leading to an intrinsic anisotropy in the bulk morphology. However, the characterization of out-of-plane nanomorphology within the active layer remains a grand challenge. Here, we utilized an X-ray scattering technique, Grazing-incident Transmission Small-angle X-ray Scattering (GTSAXS), to uncover this new morphology dimension. This technique was implemented on the model systems based on fullerene derivative (P3HT:PC71BM) and non-fullerene systems (PBDBT:ITIC, PM6:Y6), which demonstrated the successful extraction of the quantitative out-of-plane acceptor domain size of OSC systems. The detected in-plane and out-of-plane domain sizes show strong correlations with the device performance, particularly in terms of exciton dissociation and charge transfer. With the help of GTSAXS, one could obtain a more fundamental perception about the three-dimensional nanomorphology and new angles for morphology control strategies towards highly efficient photovoltaic devices.

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Annealing Behaviors of Al and Al–Mg–Si Alloy: A Real-Time Synchrotron X-ray Scattering Study

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.18942 ◽

2021 ◽

Vol 21 (3) ◽

pp. 2046-2050

Author(s):

Nan-Nan Liang ◽

Sae-Heum Park ◽

Tae-Sik Cho ◽

Seong-Goo Han

Keyword(s):

Thermal Stability ◽

Real Time ◽

Room Temperature ◽

Domain Size ◽

Thermally Stable ◽

X Ray ◽

X Ray Scattering ◽

Scattering Study ◽

Plate Type ◽

Ray Scattering

We have studied the annealing behaviors of pure Al (Al-1050) and Al–Mg–Si alloy (Al-6061) with plate-type using a real-time synchrotron X-ray scattering in vacuum. At room temperature (RT), the crystal domain size of Al phase in the Al–Mg–Si alloy was small as 70 nm, compared to that in the pure Al, 142 nm. The crystal Al phase in the Al–Mg–Si alloy has more thermal stability than that in the pure Al. The crystal Al phase in the Al–Mg–Si alloy was thermally stable in amount and size up to 250 °C. These are due to the existence of intermetallic crystal Mg2Si phase, which is thermally stable in amount and size up to 250 °C.

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