• Journal of the Korean Vacuum Society
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• v.7 no.1
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• pp.35-42
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• 1998

- The Si-$SiO_2$ interface of silicon on insulator (SOI) formed by 100 keV $O^+$ was ohserved using high resolution transmission electron microscopy (HRTEM), before and after annealing. The interface of as-implanted sample, ~$5\times 10^{17}\textrm{cm}^{-2}O^+$ implanted at $550^{\circ}C$ was very rough and it has many defectsoxide precipitate, stacking fault, coesite $SiO_2$ etc. However, the interface became flat by high temperature annealing at $1300^{\circ}C$ for 4 hour. It's roughness, observed by HRTEM, was comparable to the interface roughness of 3 keV $O_2^\;+$ ion beam oxide and -6 nm gate oxide formed by thermal oxidation.

• Analytical Science and Technology
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• v.5 no.1
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• pp.121-126
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• 1992

Transmission electron microscopy was used to investigate the structure of GaAs ${\Sigma}=19$, [110] tilt grain boundaries. Relative positions of Ga and As atoms in each grain on either side of the boundaries were determined by examining the dynamical coupling between HOLZ reflections and(200) beams. No inversion symmetry was present across the boundaries. These boundaries were observed to have a strong tendency to lie parallel to {331} planes. The atomic structure and lattice translation at these boundaries was studied in detail by high-resolution transmission electron microscopy(HRTEM). The boundary consists of units of 5-, 7-, and two 6-member rings.

• Journal of the Mineralogical Society of Korea
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• v.32 no.1
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• pp.63-69
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• 2019

The oxidation states of structural Fe in minerals reflect the paleo-depositional redox conditions for the biologically or abiotically induced mineral formation. Particularly, nano-scale analysis using high-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) is necessary to identify evidence for the microbial role in the biomineralization. HRTEM-EELS analysis of oxidation states of structural Fe and carbon bonding structure differentiate biological factors in mineralization by mapping the distribution of Fe(II)/Fe(III) and source of organic C. HRTEM-EELS technique provides geomicrobiologists with the direct nano-scale evidence of microbe-mineral interaction.

• Applied Microscopy
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• v.37 no.4
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• pp.259-269
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• 2007

In this paper we explored a possibility of observation for effects of higher-order Laue zone(HOLZ) reflections on high resolution transmission electron microscope(HRTEM) images for illumination along an off-zone axis of a crystal. The analysis of the observation could give useful three dimensional crystal structure information. For the image simulation the Howie-Whelan equation was used with modification of including HOLZ reflections. This study clearly indicates that HRTEM images for a very thin crystal tilted by a few degrees from a zone axis show the effects of HOLZ reflections and contain some information of atomic arrangements along the zone axis.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.3977-3980
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• 2012

Nanostructured thermoelectric bismuth telluride ($Bi_2Te_3$) powders with various morphologies, such as nanoplates, nanorods, and nanotubes, were prepared by a hydrothermal method based on the reaction between $BiCl_3$, Te, and sodium ethylenediaminetetraacetate ($Na_2$-EDTA) at 150, 180, and $210^{\circ}C$. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED). The effect of reaction temperature on the morphology of the $Bi_2Te_3$ particles was investigated, and the possible mechanism of morphology control was proposed.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1377-1382
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• 1995

A high-resolution transmission electron microscopy study on the lattice defects formed in the high energy P ion implanted silicon was carried out on an atomic level. Results show that Lomer dislocations, 60$^{\circ}$perfect dislocations, 60$^{\circ}$ dislocation dipole and extrinsic stacking fault formed in the near Rp of as-implanted specimen. In the annelaed specimens, interstitial Frank loops, 60$^{\circ}$perfect disolations, 60$^{\circ}$dislocation dipoles, stacking faults, precipitates, perfect dislocation loops and <112> rodlike defects existed exclusively near in the Rp with various annealing temperature and time. From these results, it is concluded that extended secondary defects as well as the point defect clusters could be formed without annealing. Even at low temperature annealing such as 55$0^{\circ}C$, small interstitial Frank loops could be formed and precipitates were also formed by $700^{\circ}C$ annealing. The defect band annealed at 100$0^{\circ}C$ for 1 hr could be divided into two regions depending on the distribution of the secondary defects.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.239.2-239.2
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• 2015

Graphene is a most interesting material due to its unique and outstanding properties. However, semi-metallic properties of graphene along with zero bandgap energy structure limit further application to optoelectronic devices. Recently, many researchers have shown that band gap can be induced in the Bernal stacked bilayer graphene. Several methods have been used for the controlled growth of the Bernal staked bilayer graphene, but it is still challenging to control the growth process. In this paper, we synthesize the large area Bernal stacked bilayer graphene using multi heating zone low pressure chemical vapor deposition (LPCVD). The synthesized bilayer graphenes are characterized by Raman spectroscopy, optical microscope (OM), scanning electron microscopy (SEM). High resolution transmission electron microscopy (HRTEM) is used for the observation of atomic resolution image of the graphene layers.

• The Korean Journal of Ceramics
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• v.7 no.2
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• pp.80-84
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• 2001

The anisotropic CdS platelets were synthesized in the lamellar bilayer phase region of the octylamine-water binary system. The influence of the synthesis conditions of the system components on morphology and size of the platelets was examined. Atomic force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM) studies have shown thickness and face size of the synthesized particles. Platelets with face sizes ranging from 50 to 250 nm and thickness from 10 to 30 nm have been synthesized at room temperature. In addition, HRTEM micrographs show that the synthesized platelets are poly crystal.

• Transactions on Electrical and Electronic Materials
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• v.4 no.3
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• pp.15-18
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• 2003

Aluminum oxide ($Al_2O_3$) materials were coated conformally on ZnO nanorods by atomic layer deposition (ALD). The ZnO nanorods were first synthesized on a Si(100) substrate from ball-milled ZnO powders by a thermal evaporation procedure. $Al_2O_3$ films were then deposited on these ZnO nanorods by ALD at a substrate temperature of $300^{\circ}C$ using trimethylaluminum (TMA) and distilled water ($H_2O$). Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the deposited ZnO nanorods revealed that amorphous $Al_2O_3$ cylindrical shells surround the ZnO nanorods. These TEM images illustrate that ALD has an excellent capability to coat any shape of nanorods conformally.

• Korean Journal of Crystallography
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• v.6 no.2
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• pp.69-74
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• 1995

GaAs tilt grain boundaries were propared by growing GaAs epilayers on Ge bicrystals by an organometallic vapor phase epitaxy (OMVPE) method ∑ =9 tilt grain boundaries were produced when two different first-order twin boundaries interacted with one another in GaAs epilayers. Structural investigations were performed for the coherent and second-order twin boundaries of GaAs by high-resolution transmission electron microscopy (HRTEM). Polarities of cross-boundary bondings were determined from the high-order Laue zone (HOLZ) lines in the (200) convergent beam disks : these were recorded from the two grains on either side of the boundaries, respectively, at particular diffraction conditions.