• Korean Journal of Materials Research
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• v.3 no.5
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• pp.482-496
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• 1993

Radiation damage and contamination of silicons etched in the $CF_4+H_2$ and $CHF_3$ magnetron discharges have been characterized using Schottky diode characteristics, TEM, AES, and SIMS as a function of applied magnetic field strength. It turned out that, as the magnetic field strength increased, the radiation damage measured by cross sectional TEM and by leakage current of Schottky diodes decreased colse to that of wet dtched samples especially for $CF_4$ plasma etched samples, For $CF_4+H_2$and $CHF_3$ etched samples, hydrogen from the plasmas introduced extended defects to the silicon and this caused increased leakage current to the samples etched at low magnetic field strength conditions by hydrogen passivation. The thickness of polymer with the increasing magnetic field strength and showed the minimum polymer residue thickness near the 100Gauss where the silicon etch rate was maximum. Also, other contaminants such as target material were found to be minimum on the etched silicon surface near the highest etch rate condition.

• Journal of Magnetics
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• v.6 no.4
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• pp.126-128
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• 2001

The effect of rapid thermal anneal (RTA) has been investigated on the properties of an FeMn exchange-biased magnetic tunnel junction (MTJ) using magnetoresistance and I-V measurements and transmission electron microscopy (TEM). The tunneling magnetoresistance (TMR) in an as-grown MTJ is found to be ∼27%, while the TMR in MTJs annealed by RTA increases with annealing temperature up to 300$\^{C}$, reaching ∼46%. A TEM image reveals a structural change in the interface of A1$_2$O$_3$layer for the MTJ annealed by RTA at 300$\^{C}$. The oxide barrier parameters are found to vary abruptly with annealing time within a few ten seconds. Our results demonstrate that the present RTA enhances the magnetoresistive properties of MTJs.

• Journal of Surface Science and Engineering
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• v.25 no.2
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• pp.97-102
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• 1992

Transimission electron microscope(TEM)/ultramicrotomy were used to characterize the detailed surface morphology of 2024-T3 Al alloy surfaces prepared by various pretreatment process. It was found that, for good and superior initial adhesive strength and durability, chemically pretreated substrates appeared essential. The film morphology developed after CSA etching treatment, ass revealed by TEM, suggested the present of irregular cell pattern with finely separated whisker-like protrusion with was responsible for increase of bond strength.

• Journal of Industrial Technology
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• v.23 no.A
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• pp.175-179
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• 2003

A study on the particle growth in $TEOS/O_2$ plasma was performed by observing the particle size and its morphology by TEM. The qualitative chemical analysis of particles was also determined by the EDS (Energy Dispersive X-Ray Spectrometer). The effects of process variables such as the plasma on-time and bubbler temperature on the particle growth were investigated. The particle size becomes larger as the plasma on-time because of the longer coagulation, and also as the bubbler temperature increases because of the faster coagulation between particles.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.44-49
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• 1998

The antimicrobial effects of HAp and Ag-HAp was observed using periprosthetic infection bacteria such as Pseudomonas Aeruginosa, Staphylococcus Epidermidis, Escherichia coli (DH5$\alpha$). Ag-HAp showed good antimicrobial effects. TEM study of E. coli with and without Ag treatment in HAp was experimented in order to find the mechanism of Ag in antimicrobial effects. It was observed that the shape of Ag-treated E. coli was changed, the cells walls became inhomogeneous. The vaculoes at cytoplasm formed into E. coli and finally it was discovered by EDAX that there were many dark granules which contain the Ag element inside the cells.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.565-569
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• 2009

The interaction between polyvinylpyrrolidone(PVP) and silver cation has been studied in water at room temperature and atmospheric pressure. The PVP and PVP/Ag composite was observed by transmission electron microscopy (TEM), UV-VIS absorption spectroscopy, Raman spectroscopy and oxygen/carbon dioxide analyzer. We identified silver cations interacting with nonbonding electrons of the oxygen atom in the carbonyl group of PVP. It was shown that PVP/Ag formed stable composites.

• ETRI Journal
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• v.26 no.5
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• pp.475-480
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• 2004

Self-assembled InAs quantum dots (QDs) embedded in an InAlGaAs matrix were grown on an InP (001) using a solid-source molecular beam epitaxy and investigated using transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. TEM images indicated that the QD formation was strongly dependent on the growth behaviors of group III elements during the deposition of InAlGaAs barriers. We achieved a lasing operation of around 1.5 ${\mu}m$ at room temperature from uncoated QD lasers based on the InAlGaAs-InAlAs material system on the InP (001). The lasing wavelengths of the ridge-waveguide QD lasers were also dependent upon the cavity lengths due mainly to the gain required for the lasing operation.

• Korean Journal of Materials Research
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• v.10 no.11
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• pp.784-788
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• 2000

The Vickers microhardness was measured on the basal (0001) plane of sapphire single crystals in the temperature range from 25$^{\circ}C$to 1000$^{\circ}C$. The substructure surrounding the indents was investigated using selective chemical polishing and etching, optical microscopy, and trasmission electron microscopy (TEM). At room temperature, cracks were predominant, and at intermediate temperatures (400$^{\circ}C$and 600$^{\circ}C$), extensive rhombohedral twinning was observed. On the other hand, at higher temperatures, prism plane slip bands on prism plane {1120}(원문참조) were dominant in the microstructure. TEM observations revealed that the dislocation substructure at the vicinity of the indents consisted of fairly straight dislocations lying in basal and/or prism planes and aligned along the <1100> and <1120> directions. The details of the glide dissociation of perfect <110> screw dislocations into three collinear 1/3<1100> partials on the prism plane and the Peierls potential for sapphire single crystals were discussed.

• Journal of the Korean Ceramic Society
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• v.37 no.1
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• pp.44-49
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• 2000

Silicon nitride powders, were synthesized by the vapor phase reaction using SiH4-NH3 gaseous mixture. The reaction temperature, ratio of NH3 to SiH4 gas and the overall gas quantity were varied. The synthesized powders were characterized using X-ray, TEM, FT-IR and EA. The synthesized silicon nitride powders were in amorphous state, and the average particle size was about 100nm. TEM analysis revealed that the particle size decreased with increasing reaction temperature and gas flow quantity. As-received amorphous powders were annealed in nitrogen atmosphere at 140$0^{\circ}C$ for 2h, then the powders were completely crystallized at 0.2 ratio of NH3 to SiH4.

• Journal of the Korean Ceramic Society
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• v.28 no.8
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• pp.654-660
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• 1991

Stabilized Zirconia (3 mol % Yttria, 3Y-TZP) was joined with intermetallic compound NiTi which has similar thermal expansion coefficient. The optimum bonding condition was determined by the Taguchi Method. Under the optimum bonding condition, the 4-point bending strength was as high as 400 MPa. bonding interfaces were examined by optical microscope, SEM, and TEM; reaction products were identified by XRD and TEM, The relationship between products and strength was examined.