Quantifying Multiple Crystallite Orientations and Crystal Heterogeneities in Complex Thin Film Materials

<p>Thin film materials have become increasingly complex in morphological and structural design. When characterizing the structure of these films, a crucial field of study is the role that crystallite orientation plays in giving rise to unique electronic properties. It is therefore important to have a comparative tool for understanding differences in crystallite orientation within a thin film, and also the ability to compare the structural orientation between different thin films. Herein, we designed a new method dubbed the mosaicity factor (MF) to quantify crystallite orientation in thin films using grazing incidence wide-angle X-ray scattering (GIWAXS) patterns. This method for quantifying the orientation of thin films overcomes many limitations inherent in previous approaches such as noise sensitivity, the ability to compare orientation distributions along different axes, and the ability to quantify multiple crystallite orientations observed within the same Miller index. Following the presentation of MF, we proceed to discussing case studies to show the efficacy and range of application available for the use of MF. These studies show how using the MF approach yields quantitative orientation information for various materials assembled on a substrate.<b></b></p>

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Grazing-incidence X-ray scattering of lamellar thin films

Journal of Applied Crystallography ◽

10.1107/s1600576719000402 ◽

2019 ◽

Vol 52 (2) ◽

pp. 247-251

Author(s):

Detlef-M. Smilgies

Keyword(s):

Thin Film ◽

Thin Films ◽

Small Molecules ◽

Film Studies ◽

Grazing Incidence ◽

Semicrystalline Polymers ◽

X Ray ◽

X Ray Scattering ◽

Incident Plane ◽

Ray Scattering

Recently, surface and thin-film studies using area detectors have become prevalent. An important class of such systems are lamellar thin films formed by small molecules, liquid crystals or semicrystalline polymers. Frequently, the lamellae align more or less parallel to the substrate. Such structures can be easily discerned by their characteristic X-ray scattering close to the incident plane. This paper describes how such patterns can be simulated, in order to extract morphological information about the thin film.

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Principal Residual Strains as A function of Depth for Sputter Deposited Mo Thin Films

MRS Proceedings ◽

10.1557/proc-356-603 ◽

1994 ◽

Vol 356 ◽

Author(s):

S. G. Malhotra ◽

Z. U. Rek ◽

L. J. Parfitt ◽

S. M. Yalisove ◽

J. C. Bilello

Keyword(s):

Thin Film ◽

Thin Films ◽

Grazing Incidence ◽

X Ray ◽

X Ray Scattering ◽

Out Of Plane ◽

Residual Strains ◽

Sputter Deposited ◽

Film Substrate ◽

Principal Strains

AbstractTraditionally, the magnitude of the stress in a thin film is obtained by measuring the curvature of the film-substrate couple; however, these techniques all measure the average stress throughout the film thickness. On a microscopic level, the details of the strain distribution as a function of depth through the thickness of the film can have important consequences in governing film quality and ultimate morphology. A new method for determining the magnitude of principal strains (strain eigenvalues) as a function of x-ray penetration depth using grazing incidence x-ray scattering for a polycrystalline thin film will be described. Results are reported for two Mo metallizations ˜ 500 Å and ˜1000 Å thick sputtered onto Si {100} substrates. The magnitude of the principal strains at several penetration depths was accomplished by an analysis of the diffraction peak shifts of at least six independent {hkl} scattering vectors from the Mo thin films. An out-of-plane strain gradient was identified in both Mo films and the strain eigenvalues were found to be anisotropic in nature. This new methodology should work with a variety of thin films and hence would provide quantitative insight into the evolution of thin film microstructure.

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Visualizing patterned thin films by grazing-incidence small-angle X-ray scattering coupled with computed tomography

Journal of Applied Crystallography ◽

10.1107/s1600576715016684 ◽

2015 ◽

Vol 48 (6) ◽

pp. 1645-1650 ◽

Cited By ~ 3

Author(s):

Hiroki Ogawa ◽

Yukihiro Nishikawa ◽

Akihiko Fujiwara ◽

Mikihito Takenaka ◽

Yi-Chin Wang ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Computed Tomography ◽

Small Angle ◽

Grazing Incidence ◽

Two Dimensional ◽

X Ray ◽

X Ray Scattering ◽

Model Sample ◽

Ray Scattering

Images of the spatial distribution of nanostructures in thin films were successfully reconstructed by grazing-incidence small-angle X-ray scattering (GISAXS) coupled with computed tomography (CT) measurements. As a model sample of inhomogeneous thin films, a thin film was patterned with four characters (F, B, S and L) consisting of nanoparticles of gold (Au), platinum (Pt), Au/Pt and Pt/Au, respectively, on a silicon substrate. The characters each produced respective two-dimensional GISAXS images which reflect the nanoparticle structures and their correlations in the thin film. The application of the GISAXS-CT technique to the characteristic scattering GISAXS intensity of each component enables one to reconstruct the images of each character independently. Moreover, it was found that the patterned images could be reconstructed even from very weak scattered intensities at higherqpositions and the diffuse intensities. These results indicate that the GISAXS-CT method is a powerful tool to obtain distinct reconstruction images detailing the particle size, shape and surface roughness.

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Evolution of Interfacial Roughness Correlations of Fe Au Films Grown on Mgo(001) Substrates

MRS Proceedings ◽

10.1557/proc-440-359 ◽

1996 ◽

Vol 440 ◽

Author(s):

P. C. Chow ◽

R. Paniago ◽

R. Forrest ◽

S. C. Moss ◽

S. S. P. Parkin ◽

...

Keyword(s):

Thin Films ◽

Diffuse Scattering ◽

Perfect Match ◽

Grazing Incidence ◽

Interface Roughness ◽

Metallic Structures ◽

X Ray ◽

Dimensional Image ◽

X Ray Scattering ◽

Image Plate Detector

AbstractThe growth by sputtering of a series of thin films of Fe/Au on MgO(001) substrates was analyzed using Bragg and diffuse X-ray scattering. The Fe (bcc) layer grows rotated by 45° with respect to the MgO – Au(fcc) (001) epitaxial orientation, resulting in an almost perfect match between the two metallic structures. By collecting the X-ray diffuse scattering under grazing incidence using a 2-dimensional image plate detector, we mapped the reciprocal space of these films. We characterized the correlated interface roughness starting with a buffer of Fe in which only three interfaces are present. The propagation of the roughness was subsequently characterized for Fe/Au multilayers with 40 and 100 bilayers. We observe an enlargement of the surface features as a function of time, evidenced by the longer lateral cutoff length measured for thicker films.

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