When dendrimers are not better – rational design of nanolayers for high-performance organic electronic devices

Several generations of carbosilane dendrimers with quaterthiophene end groups were studied by X-ray scattering, differential scanning calorimetry, polarizing optical and atomic force microscopy and molecular modelling.

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In situ X-ray Scattering Study of the Formation of Au Nano Crystals During Thermal Annealing

MRS Proceedings ◽

10.1557/proc-1027-d07-04 ◽

2007 ◽

Vol 1027 ◽

Author(s):

Do Young Noh ◽

Ki-Hyun Ryu ◽

Hyon Chol Kang

Keyword(s):

Thermal Annealing ◽

Bragg Reflection ◽

Ex Situ ◽

X Ray ◽

Force Microscopy ◽

X Ray Scattering ◽

Atomic Force ◽

Au Thin Films ◽

Ray Scattering

AbstractThe transformation of Au thin films grown on sapphire (0001) substrates into nano crystals during thermal annealing was investigated by in situ synchrotron x-ray scattering and ex situ atomic force microscopy (AFM). By monitoring the Au(111) Bragg reflection and the low Q reflectivity and comparing them with ex situ AFM images, we found that polygonal-shape holes were nucleated and grow initially. As the holes grow larger and contact each other, their boundary turns into Au nano crystals. The Au nano crystals have a well-defined (111) flat top surface and facets in the in-plane direction.

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Intrinsic roughness and interfaces of Cr/Be multilayers

Journal of Applied Crystallography ◽

10.1107/s160057672101027x ◽

2021 ◽

Vol 54 (6) ◽

Author(s):

Roman Pleshkov ◽

Nikolay Chkhalo ◽

Vladimir Polkovnikov ◽

Mikhail Svechnikov ◽

Maria Zorina

Keyword(s):

Atomic Force Microscopy ◽

Optical Contrast ◽

Multilayer Mirrors ◽

X Ray ◽

Force Microscopy ◽

Layer Material ◽

Multilayer Mirror ◽

X Ray Scattering ◽

Atomic Force ◽

Sharp Structure

The structures of Cr/Be multilayer mirror interfaces are investigated using X-ray reflectometry, diffuse X-ray scattering and atomic force microscopy. The combination of these methods makes it possible to separate the contributions of roughness and interlayer diffusion/intermixing for each sample. In the range of period thicknesses of 2.26–0.8 nm, it is found that the growth roughness of the Cr/Be multilayer mirrors does not depend on the period thickness and is ∼0.2 nm. The separation of roughness and diffuseness allows estimation of layer material intermixing and the resulting drop in the optical contrast, which is from 0.85 to 0.17 in comparison with an ideally sharp structure.

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Comparative study of the roughness of optical surfaces and thin films by use of x-ray scattering and atomic force microscopy

Applied Optics ◽

10.1364/ao.38.000684 ◽

1999 ◽

Vol 38 (4) ◽

pp. 684 ◽

Cited By ~ 22

Author(s):

Victor E. Asadchikov ◽

Angela Duparré ◽

Stefan Jakobs ◽

Albert Yu. Karabekov ◽

Igor V. Kozhevnikov ◽

...

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Comparative Study ◽

X Ray ◽

Force Microscopy ◽

Optical Surfaces ◽

X Ray Scattering ◽

Atomic Force ◽

Ray Scattering

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Microstructural Characterization of Polyanhydride Blends for Controlled Drug Delivery

MRS Proceedings ◽

10.1557/proc-662-nn4.2 ◽

2000 ◽

Vol 662 ◽

Cited By ~ 1

Author(s):

Elizabeth E. Shen ◽

Hsin-Lung Chen ◽

Balaji Narasimhan

Keyword(s):

Drug Delivery ◽

Microstructural Characterization ◽

Peak Shift ◽

Crystalline Morphology ◽

X Ray ◽

Force Microscopy ◽

X Ray Scattering ◽

Atomic Force ◽

Drug Delivery Devices

AbstractThis research examines the microstructure of polyanhydride blends for use in drug delivery devices. Atomic force microscopy (AFM) and small-angle X-ray scattering (SAXS) studies were performed on the homopolymers and blends of the polyanhydrides poly(1,6-carboxyphenoxy hexane) (CPH) and poly(sebacic anhydride) (SA). AFM of the CPH/SA blends 20:80, 50:50, and 80:20 showed distinct patterns indicating spinodal decomposition and phase separation on the micron-scale. Because it has been shown that incorporated drugs will thermodynamically partition into phase-separated domains depending on their hydrophobicity, polyanhydride blends will be able to encapsulate larger bioactive compounds including nucleotides, proteins, and vaccines. Preliminary SAXS studies of the CPH/SA blend systems provide information on the crystalline morphology of the polymer. A peak shift to a lower q from poly(SA) to the blends indicates that the poly(CPH) is incorporated into and causes swelling of the interlamellar amorphous regions of poly(SA).

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