Heteroepitaxy of Ge on Cube-Textured Ni(001) Foils Through CaF2 Buffer Layer

ABSTRACTEpitaxial Ge films are useful as a substrate for high-efficiency solar cell applications. It is possible to grow epitaxial Ge films on low cost, cube textured Ni(001) sheets using CaF2(001) as a buffer layer. Transmission electron microscopy (TEM) analysis indicates that the CaF2(001) lattice has a 45o in-plane rotation relative to the Ni(001) lattice. The in-plane epitaxy relationships are CaF2[110]//Ni[100] and CaF2[$\bar 1$10]//Ni[010]. Energy dispersive spectroscopy (EDS) shows a sharp interface between Ge/CaF2 as well as between CaF2/Ni. Electron backscatter diffraction (EBSD) shows that the Ge(001) film has a large grain size (∼50 μm) with small angle grain boundaries (< 8o). The epitaxial Ge thin film has the potential to be used as a substrate to grow high quality III-V and II-VI semiconductors for optoelectronic applications.

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High Quality GaAs Epilayers Grown on Si Substrate Using 100 nm Ge Buffer Layer

International Journal of Photoenergy ◽

10.1155/2016/7218310 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Wei-Cheng Kuo ◽

Hung-Chi Hsieh ◽

Wu Chih-Hung ◽

Huang Wen-Hsiang ◽

Chien-Chieh Lee ◽

...

Keyword(s):

Buffer Layer ◽

High Efficiency ◽

Electron Cyclotron Resonance ◽

Low Cost ◽

Chemical Vapor ◽

Buffer Layers ◽

High Quality ◽

Tandem Solar Cells ◽

Hydrogen Flow ◽

Transmission Electron

We present high quality GaAs epilayers that grow on virtual substrate with 100 nm Ge buffer layers. The thin Ge buffer layers were modulated by hydrogen flow rate from 60 to 90 sccm to improve crystal quality by electron cyclotron resonance chemical vapor deposition (ECR-CVD) at low growth temperature (180°C). The GaAs and Ge epilayers quality was verified by X-ray diffraction (XRD) and spectroscopy ellipsometry (SE). The full width at half maximum (FWHM) of the Ge and GaAs epilayers in XRD is 406 arcsec and 220 arcsec, respectively. In addition, the GaAs/Ge/Si interface is observed by transmission electron microscopy (TEM) to demonstrate the epitaxial growth. The defects at GaAs/Ge interface are localized within a few nanometers. It is clearly showed that the dislocation is well suppressed. The quality of the Ge buffer layer is the key of III–V/Si tandem cell. Therefore, the high quality GaAs epilayers that grow on virtual substrate with 100 nm Ge buffer layers is suitable to develop the low cost and high efficiency III–V/Si tandem solar cells.

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Where are the geometrically necessary dislocations accommodating small imprints?

Journal of Materials Research ◽

10.1557/jmr.2009.0131 ◽

2009 ◽

Vol 24 (3) ◽

pp. 647-651 ◽

Cited By ~ 10

Author(s):

M. Rester ◽

C. Motz ◽

R. Pippan

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Twin Boundary ◽

Crystal Orientation ◽

Electron Backscatter Diffraction ◽

Transmission Electron ◽

Electron Backscatter ◽

Copper Single Crystals ◽

Backscatter Diffraction ◽

Small Misorientation

Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analyses of small indentations in copper single crystals exhibit only slight changes of the crystal orientation in the surroundings of the imprints. Far-reaching dislocations might be the reason for these small misorientation changes. Using EBSD and TEM technique, this work makes an attempt to visualize the far-propagating dislocations by introducing a twin boundary in the vicinity of small indentations. Because dislocations piled up at the twin boundary produce a misorientation gradient, the otherwise far-propagating dislocations can be detected.

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Resolution of transmission electron backscatter diffraction in aluminum and silver: Effect of the atomic number

Ultramicroscopy ◽

10.1016/j.ultramic.2018.06.019 ◽

2018 ◽

Vol 193 ◽

pp. 126-136 ◽

Cited By ~ 1

Author(s):

Chia-Wei Kuo ◽

Jui-Chao Kuo ◽

Sheng-Chang Wang

Keyword(s):

Atomic Number ◽

Electron Backscatter Diffraction ◽

Transmission Electron ◽

Electron Backscatter ◽

Backscatter Diffraction

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Reduced Unit Cell Determination From Unindexed EBSD Patterns

Microscopy and Microanalysis ◽

10.1017/s1431927600037223 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 946-947 ◽

Cited By ~ 1

Author(s):

J. R. Michael ◽

R. P. Goehner

Keyword(s):

Electron Microscope ◽

Electron Backscatter Diffraction ◽

Unit Cell ◽

Phase Identification ◽

High Quality ◽

Charge Coupled Device ◽

Transmission Electron ◽

Single Pattern ◽

Backscatter Diffraction

Electron backscatter diffraction (EBSD) is a technique that can provide identification of unknown crystalline phases while exploiting the excellent imaging capabilities of the scanning electron microscope (SEM). Phase identification using EBSD has now progressed to the point that it is commercially available. Phase identification in the SEM requires high quality EBSD patterns that can only be collected using either film or charge coupled device (CCD)-based cameras. High quality EBSD patterns obtained in this manner show many diffraction features that are useful in the determination of the unit cell of the sample.’ This paper will discuss the features in the EBSD patterns and the procedure used to determine the reduced unit cell of the sample.One of the major advantages of EBSD over electron diffraction in the transmission electron microscope is the remarkable field of view that is routinely attained. The large angular view of the diffraction pattern permits many zone axes and their associated symmetries to be viewed in a single pattern or at most a few patterns.

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Coupling Automated Electron Backscatter Diffraction with Transmission Electron and Atomic Force Microscopies

Microscopy and Microanalysis ◽

10.1017/s1431927600037193 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 940-941

Author(s):

A.J. Schwartz ◽

M. Kumar ◽

P.J. Bedrossian ◽

W.E. King

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Thermomechanical Processing ◽

Electron Backscatter Diffraction ◽

Grain Boundary Character Distribution ◽

Atomic Force ◽

Transmission Electron ◽

Electron Backscatter ◽

Network Engineering ◽

Backscatter Diffraction

Grain boundary network engineering is an emerging field that encompasses the concept that modifications to conventional thermomechanical processing can result in improved properties through the disruption of the random grain boundary network. Various researchers have reported a correlation between the grain boundary character distribution (defined as the fractions of “special” and “random” grain boundaries) and dramatic improvements in properties such as corrosion and stress corrosion cracking, creep, etc. While much early work in the field emphasized property improvements, the opportunity now exists to elucidate the underlying materials science of grain boundary network engineering. Recent investigations at LLNL have coupled automated electron backscatter diffraction (EBSD) with transmission electron microscopy (TEM)5 and atomic force microscopy (AFM) to elucidate these fundamental mechanisms.An example of the coupling of TEM and EBSD is given in Figures 1-3. The EBSD image in Figure 1 reveals “segmentation” of boundaries from special to random and random to special and low angle grain boundaries in some grains, but not others, resulting from the 15% compression of an Inconel 600 polycrystal.

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Effect of microscope parameter and specimen thickness of spatial resolution of transmission electron backscatter diffraction

Journal of Microscopy ◽

10.1111/jmi.12413 ◽

2016 ◽

Vol 264 (1) ◽

pp. 34-40 ◽

Cited By ~ 11

Author(s):

Y.Z. WANG ◽

M.G. KONG ◽

Z.W. LIU ◽

C.C. LIN ◽

Y. ZENG

Keyword(s):

Spatial Resolution ◽

Electron Backscatter Diffraction ◽

Specimen Thickness ◽

Transmission Electron ◽

Electron Backscatter ◽

Backscatter Diffraction

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Transmission Electron Backscatter Diffraction (tEBSD) analysis of Au Thin Films

Microscopy and Microanalysis ◽

10.1017/s1431927615009137 ◽

2015 ◽

Vol 21 (S3) ◽

pp. 1671-1672

Author(s):

Eliot Estrine ◽

Nicholas Seaton ◽

Prabesh Dulal ◽

Bethanie Stadler

Keyword(s):

Thin Films ◽

Electron Backscatter Diffraction ◽

Transmission Electron ◽

Electron Backscatter ◽

Au Thin Films ◽

Backscatter Diffraction

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Formation of Nanoporous Gold Studied by Transmission Electron Backscatter Diffraction

Microscopy and Microanalysis ◽

10.1017/s1431927615015329 ◽

2015 ◽

Vol 21 (6) ◽

pp. 1387-1397 ◽

Cited By ~ 3

Author(s):

Leo T.H. de Jeer ◽

Diego Ribas Gomes ◽

Jorrit E. Nijholt ◽

Rik van Bremen ◽

Václav Ocelík ◽

...

Keyword(s):

Crystallographic Texture ◽

Manufacturing Process ◽

Electron Backscatter Diffraction ◽

Nanoporous Materials ◽

Nanoporous Gold ◽

Grain Structure ◽

Misorientation Distribution ◽

Transmission Electron ◽

Electron Backscatter ◽

Backscatter Diffraction

AbstractTransmission electron backscatter diffraction (t-EBSD) was used to investigate the effect of dealloying on the microstructure of 140-nm thin gold foils. Statistical and local comparisons of the microstructure between the nonetched and nanoporous gold foils were made. Analyses of crystallographic texture, misorientation distribution, and grain structure clearly prove that during the dealloying manufacturing process of nanoporous materials the crystallographic texture is enhanced significantly with a clear decrease of internal strain, whereas maintaining the grain structure.

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