• Journal of the Korean Magnetic Resonance Society
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• v.6 no.1
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• pp.38-44
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• 2002

60% Pt on Vulcan XC-72 with similar Pt sizes to fuel cell grade Pt black was investigated by $\^$13/C nuclear magnetic resonance spectroscopy (NMR), cyclic voltammery (CV), transmission electron microscopy (TEM). Experiments were carried out on electrochemically cleaned samples as well as as-received. The TEM and CV results showed that the average particle sizes were changed by cleaning. However, the chemical shift （$\delta$$\_$G/） of $\^$13/C of $\^$13/CO absorbed on Pt surfaces did not show any appreciable variation with particle size change as did in Pt black. These results indicate that a combination of different analytic techniques is essential to understand the properties of the metal particle catalysts and that the presence of carbon black support strongly influences the NMR data, probably through metal-support interaction.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.8
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• pp.1250-1254
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• 1990

The cordierite (MgO, SiO2, Al2O3) is of great interest for microelectronic packaging of integrated circuits. Its main advantages are low dielectric constant and low thermal expansion. The cordierite precursor is obtained by sol-gel synthesis using organic and inorganic compounds. The obtained cordierite precursor is an amorphous state at about 900\ulcorner. Green and fired cordierite samples were studied by SEM. Microanalysis X and TEM for microscopic properties. The fired cordierite shows forte diminution of Mg in comparison with its value at volume and the deficit of Mg compensates by sugmentation of Al and Si \ulcornercordierite and \ulcornercordierite are present near the surface (< 100) and small quantities of magnesium aluminate (MgAl2O4)is presented spinnel phase.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.2
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• pp.15-18
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• 2001

The Mo/si multilayer for EUV lithography was deposited using magnetron sputtering system. The multilayers were characterized using the cross-sectional transmission electron microscope (TEM) and low/high angle X-ray diffraction (XRD). The microstructure of Mo and Si was highly textured structure and amorphous, respectively. The well-defined low angle XRD peaks implies a well-defined multilayer structure. The interfacial layer of Mo-on-Si was thicker than Si-on-Mo interfacial layer.

• Korean Journal of Poultry Science
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• v.17 no.1
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• pp.1-6
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• 1990

For the production of tetraploid embryos in chicken through induction of diploid gametes. The experiment was found results as follows; 1. Induction of diploid sperm was observed 11% from embryos of normal females and males at 12 days after injection of 0.37mg per 2kg body weight for three days. 2. 3 among 109 embryos from crosses of diploid gametes induced by TEM were found as tetraploid. 3. Genetic structures of tetraploid embryos were indentified as normal 4 pairs chromosomes without certain variation.

• Journal of the Korean Ceramic Society
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• v.44 no.4 s.299
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• pp.202-207
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• 2007

High-Quality 1-Dimensional InN single crystalline have been grown by Halide Vapor-Phase Epitaxy on the Au catalyst coated Si substrate using the vapor-liquid-solid growth mechanism. We have been grown 1-dimension InN nanowires having controlled the growth conditions for substrate temperature and gases flow rate. The grown InN nanowire of characteristics for morphologies, crystal structure, and element analysis were carried out by SEM, HR-TEM, and EDS respectively. And the defects of InN crystalline were analyzed by indexing of selective area diffraction pattern with attached HR-TEM. We have successfully obtained the defect-free 1-dimensional InN single crystalline nanowire at the atmosphere pressure.

• Journal of Surface Science and Engineering
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• v.35 no.5
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• pp.289-294
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• 2002

ZnTe films have been grown on (100) GaAs substrate with two representative problems. The one is lattice mismatch, the other is thermal expansion coefficients mismatch of ZnTe /GaAs. It claims here, the relationship of film thickness and defects distribution with (100) ZnTe/GaAs using hot wall epitaxy (HWE) growth was investigated by transmission electron microscopy (TEM). It analyzed on the two-sort side using TEM with cross-sectional transmission electron microscopy (XTEM) and high-resolution electron microscopy (HREM). Investigation into the nature and behavior of dislocations with dependence-thickness in (100) ZnTe/ (100) GaAs hetero-structures grown by transmission electron microscopy (TEM). This defects range from interface to 0.7 $\mu\textrm{m}$ was high density, due to the large lattice mismatch and thermal expansion coefficients. The defects of low density was range 0.7$\mu\textrm{m}$~1.8$\mu\textrm{m}$. In the thicker range than 1.8$\mu\textrm{m}$ was measured hardly defects.

• Journal of Powder Materials
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• v.24 no.4
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• pp.285-291
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• 2017

We propose a custom analysis technique for the dark field (DF) image based on transmission electron microscopy (TEM). The custom analysis technique is developed based on the $DigitalMicrograph^{(R)}$ (DM) script language embedded in the Gatan digital microscopy software, which is used as the operational software for most TEM instruments. The developed software automatically scans an electron beam across a TEM sample and records a series of electron diffraction patterns. The recorded electron diffraction patterns provide DF and ADF images based on digital image processing. An experimental electron diffraction pattern is recorded from a IrMn polycrystal consisting of fine nanograins in order to test the proposed software. We demonstrate that the developed image processing technique well resolves nanograins of ~ 5 nm in diameter.

• Journal of Surface Science and Engineering
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• v.32 no.4
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• pp.503-512
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• 1999

The crystal structure and the microstructure of the intermetallic compounds formed in the interface between In solder and Au/Ni/Ti thin films have been investigated by XRD, SEM, and TEM. Indium solder was deposited on the Au/Ni/Ti thin films/Si substrate by evaporation. The heat treatments simulated the flip chip solder joining were performed in RTA system or in furnace. $Auln_2$ phase is formed in all specimens.$ In_{27}$ $Ni_{10}$ and/or $In_{X}$ $Ni_{Y}$ phase are formed in the interface between $Auln_2$ and Ni depending the heat treatment conditions.

• The Korean Journal of Ceramics
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• v.3 no.3
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• pp.155-158
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• 1997

Highly oriented diamond films were deposited on a (100) silicon substrate by bias enhanced nucleation technique. Both plan-view and cross-section TEM were applied to study the nucleation and growth mechanism of diamond grains. Randomly oriented polycrystalline diamond grains with internal microtwins were observed at the nucleation stage while defect free regions were retained at the growth stage and were apparently related with the epitaxy of diamond films. From our experimental results, the nucleation and texture formation mechanism of diamond films is discussed.

• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1274-1279
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• 1998

The glass forming ability of the PbO-B2O3-TiO3-BaO system was investigated in relation to transitieon tem-peratures and the atomic ratio between constituents. Glass forming tendency was improved as the tem-peratures and the atomic ratio between constituents. Glass forming tendency was improved as the tem-perature differences between liquidus temperature and crystallization(or glass transition) temperature de-creased and the temperature difference between crystallization and glass transition temperature increases. The atomic ratio could be used as a criterion to deign glass systems. The interposition of B and Ba atoms between Pb and Ti atoms was one of important factors in glass formation.