• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.169-169
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• 2003

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.168-168
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.11a
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• pp.37-38
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• 2000

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.92.2-92
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.93.1-93
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• 2003

• Applied Science and Convergence Technology
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• v.27 no.1
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• pp.9-13
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• 2018

Samples of anodic oxide film used in semiconductor and display manufacturing processes were prepared at different electrolyte temperatures to investigate the corrosion resistance. The anodic oxide film was grown on aluminum alloy 6061 by using a sulfuric acid ($H_2SO_4$) electrolyte of 1.5 M at $0^{\circ}C$, $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $20^{\circ}C$. The insulating properties of the samples were evaluated by measuring the breakdown voltage, which gradually increased from 0.43 kV ($0^{\circ}C$) to 0.52 kV ($5^{\circ}C$), 1.02 kV ($10^{\circ}C$), and 1.46 kV ($15^{\circ}C$) as the electrolyte temperature was increased from $0^{\circ}C$ to $15^{\circ}C$, but then decreased to 1.24 kV ($20^{\circ}C$). To evaluate the erosion of the film by fluorine plasma, the plasma erosion and the contamination particles were measured. The plasma erosion was evaluated by measuring the breakdown voltage after exposing the film to $CF_4/O_2/Ar$ and $NF_3/O_2/Ar$ plasmas. With exposure to $CF_4/O_2/Ar$ plasma, the breakdown voltage of the film slightly decreased at $0^{\circ}C$, by 0.41 kV; however, the breakdown voltage significantly decreased at $20^{\circ}C$, by 0.83 kV. With exposure to $NF_3/O_2/Ar$ plasma, the breakdown voltage of the film slightly decreased at $0^{\circ}C$, by 0.38 kV; however, the breakdown voltage significantly decreased at $20^{\circ}C$, by 0. 77 kV. In addition, for the entire temperature range, the breakdown voltage decreased more when sample was exposed to $NF_3/O_2/Ar$ plasma than to $CF_4/O_2/Ar$ plasma. The decrease of the breakdown voltage was lower in the anodic oxide film samples that were grown slowly at lower temperatures. The rate of breakdown voltage decrease after exposure to fluorine plasma was highest at $20^{\circ}C$, indicating that the anodic oxide film was most vulnerable to erosion by fluorine plasma at that temperature. Contamination particles generated by exposure to the $CF_4/O_2/Ar$ and $NF_3/O_2/Ar$ plasmas were measured on a real-time basis. The number of contamination particles generated after the exposure to the respective plasmas was lower at $5^{\circ}C$ and higher at $0^{\circ}C$. In particular, for the entire temperature range, about five times more contamination particles were generated with exposure to $NF_3/O_2/Ar$ plasma than for exposure to $CF_4/O_2/Ar$ plasma. Observation of the surface of the anodic oxide film showed that the pore size and density of the non-treated film sample increased with the increase of the temperature. The change of the surface after exposure to fluorine plasma was greatest at $0^{\circ}C$. The generation of contamination particles by fluorine plasma exposure for the anodic oxide film prepared in the present study was different from that of previous aluminum anodic oxide films.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.2078-2084
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• 2020

Magnesium oxide (MgO) and Zinc oxide (ZnO) nanoparticles (NPs) have been successfully synthesized by solid-solid reaction method. The structural properties of ZnO and MgO NPs were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results indicated a formation of pure MgO and ZnO NPs. The mean diameter values of the agglomerated particles were around to be 70 and 50 nm for MgO and ZnO NPs, respectively using SEM analysis. Further, a wide-range of nuclear radiation shielding investigation for gamma-ray and fast neutrons have been studied for Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. FLUKA and Microshield codes have been employed for the determination of mass attenuation coefficients (μ_m) and transmission factors (TF) of Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. The calculated values for mass attenuation coefficients (μ_m) were utilized to determine other vital shielding properties against gamma-ray radiation. Moreover, the results showed that Zinc oxide (ZnO) nanoparticles with the lowest diameter value as 50 nm had a satisfactory capacity in nuclear radiation shielding.

• Journal of Welding and Joining
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• v.14 no.2
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• pp.46-56
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• 1996

HAZ impact toughness of Ti-oxide steel was investigated and compared to that of a conventional Ti-nitride steel. Toughness variations of each steel with weld peak temperatures and cooling rates were interpreted with microstructural transformation characteristics. In contrast to Ti-nitride steel showing continuous decrease in HAZ toughness with peak temperature, Ti-oxide steel showed increase in HAZ toughness above $1400^{\circ}C$ peak temperature. The HAZ microstructure of the Ti-oxide steel is characterized by the formation of intragranular ferrite plate, which was found to start from Ti-oxide particles dispersed in the matrix of the steel. Large austenite grain size above $1400^{\circ}C$ promoted intragranular ferrite plate formation in Ti-oxide steel while little intragranular ferrite plate was formed in Ti-nitride steel because of dissolution of Ti-nitrides. Ti-oxides in the Ti-oxide steel usually contain MnS and have crystal structures of TiO and/or $Ti_2O_3$.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.694-702
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• 2014

The micron-sized ITO(indium tin oxide) particles were prepared by spray pyrolysis from aqueous precursor solutions for indium, and tin and organic additives solution. Organic additives solution with citric acid(CA) and ethylene glycol(EG) were added to aqueous precursor solution for Indium and Tin. The obtained ITO particles prepared by spray pyrolysis from the aqueous solution without organic additives solution had spherical and filled morphologies whereas the obtained ITO particles with organic additives solution had more hollow and porous morphologies with increasing mole of organic additives. The micron-sized ITO particle with organic additives was changed fully to nano-sized ITO particle whereas the micron-sized ITO particle without organic additives was not changed fully to nano-sized ITO particle after post-treatment at $700^{\circ}C$ for 2 hours and wet-ball milling for 24 hours. The size of primary ITO particle by Debye-Scherrer formula and surface resistance of ITO pellet were measured.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.608-613
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• 2003

In order to remove particles on surface of post-oxide CMP wafer, new cleaning solution was prepared by mixing with DHF (Diluted HF), nonionic surfactant PAAE (Polyoxyethylene Alkyl Aryl Ether), DMSO (Dimethylsulfoxide) and D.I.W.. Silicone wafers were intentionally contaminated by silica, alumina and PSL (polystylene latex) which had different zeta potentials in cleaning solution. This cleaning solution under megasonic irradiation could remove particles and metals simultaneously at room temperature in contrast to traditional AMP (mixture of $NH_4OH,\;H_2O_2$ and D.I.W) without any side effects such as increasing of microroughness, metal line corrosion and deposition of organic contaminants. This suggests that this cleaning solution would be useful future application with copper CMP in brush cleaning process as well as traditional post CMP cleaning process.