Investigation of the Atomic Structures of Si3N4/CeO2-δ Interfaces using Atomic Resolution Z-contrast Imaging and EELS combined with First-Principles Methods

ABSTRACTFirst-principles density-functional calculations were used to study the effects of Ca impurities on the Σ=5 (310) <001> tilt grain boundaries in MgO. An equilibrium structure and two metastable structures of the grain boundaries in pure MgO have been established. The calculations further demonstrated that Ca impurities segregate at particular sites in the metastable grain boundary and induce a structural transformation. This result is consistent with atomic resolution Z-contrast imaging. The calculations also found that the impurities at the grain boundaries do not induce states in the band gap. The mechanism of the transformation is also discussed.

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Simultaneous atomic-resolution electron ptychography and Z-contrast imaging of light and heavy elements in complex nanostructures

Nature Communications ◽

10.1038/ncomms12532 ◽

2016 ◽

Vol 7 (1) ◽

Cited By ~ 103

Author(s):

H. Yang ◽

R. N. Rutte ◽

L. Jones ◽

M. Simson ◽

R. Sagawa ◽

...

Keyword(s):

Atomic Resolution ◽

Heavy Elements ◽

Contrast Imaging ◽

Resolution Electron ◽

Z Contrast ◽

Complex Nanostructures

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Atomic resolution Z-contrast imaging of semiconductors

Journal of Electron Microscopy ◽

10.1093/oxfordjournals.jmicro.a023803 ◽

2000 ◽

Vol 49 (2) ◽

pp. 231-244 ◽

Cited By ~ 8

Author(s):

Y. Xin ◽

E. M. James ◽

N. D. Browning ◽

S. J. Pennycook

Keyword(s):

Atomic Resolution ◽

Contrast Imaging ◽

Z Contrast

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Quantitative HREM: Reliable Structure Determination of Grain Boundaries in SrTiO3

Microscopy and Microanalysis ◽

10.1017/s1431927600027628 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 310-311

Author(s):

Thomas Gemming

Keyword(s):

Imaging Techniques ◽

Quantitative Information ◽

Small Error ◽

Atomic Resolution ◽

Short Exposure ◽

Contrast Imaging ◽

Short Exposure Time ◽

Analysis Of The Images ◽

Pm 10 ◽

Z Contrast

High resolution transmission electron microscopy (HREM) is an excellent experimental method to image grain boundary structures with atomic resolution. The advantage of the method is the short exposure time of only about one second that is needed to record an image. Other methods like Z-contrast imaging require much longer exposure times and are therefore much more prone to specimen drift during recording. However there is the remaining difficulty to HREM that the evaluation of experimental images is not straightforward and a thorough analysis of the images is necessary in order to deduce quantitative information with small error bars of only a few pm (10-15m). A second inherent difficulty common to all atomic resolution imaging techniques is that the information is retrieved from a very small area of a specimen. The question arising from that is: can we nevertheless be sure to obtain a representative answer to a “real world” material science problem? A positive answer to this question is given by the investigations presented here.

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Atomic Structures of Oxygen-associated Defects in Sintered Aluminum Nitride Ceramics

Microscopy and Microanalysis ◽

10.1017/s1431927699000185 ◽

1999 ◽

Vol 5 (5) ◽

pp. 352-357 ◽

Cited By ~ 5

Author(s):

Yanfa Yan ◽

S. J. Pennycook ◽

M. Terauchi ◽

M. Tanaka

Keyword(s):

Stacking Sequence ◽

Contrast Imaging ◽

Octahedral Layer ◽

Atomic Structures ◽

Inversion Domain ◽

Sintered Aluminum ◽

Domain Boundaries ◽

Convergent Beam ◽

Z Contrast ◽

Inversion Domain Boundaries

Convergent-beam electron diffraction and Z-contrast imaging are used to study oxygen-associated defects, flat inversion domain boundaries, dislocations, and interfaces in sintered AlN ceramics. The structures of these defects are directly derived from atomic-resolution Z-contrast images. The flat inversion domain boundaries contain a single Al-O octahedral layer and have a stacking sequence of . . .bAaB-bAc-CaAc. . , where -cAb- indicates the single octahedral layer. The expansion at the flat inversion domain boundaries is measured to be 0.06 (±0.02) nm. The interfaces between 2H- and polytypoid-AlN are found to be also inversion domain boundaries but their stacking sequence differs from that of the flat inversion domain boundaries.

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Bonding, Defects, And Defect Dynamics In The Sic-SiO2 System

MRS Proceedings ◽

10.1557/proc-640-h3.3 ◽

2000 ◽

Vol 640 ◽

Cited By ~ 2

Author(s):

S. T. Pantelides ◽

R. Buczko ◽

M. Di Ventra ◽

S. Wang ◽

S.-G. Kim ◽

...

Keyword(s):

First Principles ◽

Oxidation Process ◽

Atomic Scale ◽

Contrast Imaging ◽

Interface Defects ◽

Device Applications ◽

Z Contrast ◽

And Control ◽

Electron Energy Loss ◽

Ultimate Purpose

ABSTRACTThis paper presents a review of new results obtained by a combination of first-principles theory, Z-contrast imaging, and electron-energy-loss spectroscopy in the context of a broader experimental/theoretical program to understand and control the atomic-scale structure of SiCSiO2 interfaces. The ultimate purpose is to achieve low interface trap densities for device applications. Results are given for global bonding arrangements in comparison with those of the Si-SiO2 interface, the mechanism of the oxidation process, the nature of possible interface defects and their passivation by N and H, and the formation and dissolution of C clusters in SiO2 during oxidation and reoxidation.

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