• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.705-709
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• 2005

In order to clarify the heat annealing process for Magnesium Oxide (MgO), cathodoluminescent (CL) analysis was performed. Our results in the present work prove that the heat annealing has effects on not only removing water from the surface of MgO, but also increasing density of O and Mg defect pairs. It is the first work that the influence of annealing process on physical properties of the vacuum evaporated MgO thin films by using CL spectra.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.2
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• pp.79-83
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• 2002

As Ag does not form my silicide on Si surfaces, Ag wire is a candidate for self-assembled nanowire on the reconstructed and single-domain Si(5 5 12)-2 $\times$ 1. In the present study, various Ag coverages and post-annealing temperatures had been tested to fabricate a Ag nanowire with high aspect ratio. When Ag coverage was less than 0.03 ML and the post-annealing temperature was 500(C, Ag atoms preferentially adsorbed on the tetramer sites resulting in Ag wires with an inter-row spacing of ~5 nm. However, its aspect ratio is relatively small and its height is also not even. On the other hand, the Ag-posited surface completely loses its reconstruction even with the same annealing at 500 $\^{C}$ if the initial coverage exceeds 0.05 ML. But the additional subsequent annealing at 700$\^{C}$ and slow-cooling process recovers the well-ordered Ag chain with relatively high aspect ratio on the same tetramer sites. It can be understood that, in the double step annealing process, the lower temperature annealing is required for cohesion of adsorbed Ag atoms and the higher temperature annealing is for providing Ag atoms to the tetramer sites.

• Korean Journal of Metals and Materials
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• v.47 no.5
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• pp.316-321
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• 2009

Co nanoparticles on silica substrates were fabricated by inducing a thin-film dewetting through two different processes-furnace annealing and pulsed-laser annealing. The effects of annealing temperature, film thickness and laser energy density on dewetting morphology and mechanism were investigated. Co thinfilms with thicknesses between 3 to 15 nm were deposited using ion-beam sputtering, and then, in order to induce dewetting, thermally annealed in furnace at temperatures between 600 and $900^{\circ}C$. Some as-deposited films were irradiated using a Nd-YAG pulsed-laser of 266 nm wavelength to induce dewetting in liquid-state. Films annealed in furnace agglomerated to form nanoparticles above $700^{\circ}C$, and those average particle size and spacing were increased with an increase of film thickness. On the laser annealing process, above the energy density of $100mJ/cm^2$, metal films were completely dewetted and the agglomerated particles exhibited greater size uniformity than those on the furnace annealing process. A detailed dewetting mechanism underlaying both processes were discussed.

• Current Photovoltaic Research
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• v.7 no.1
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• pp.1-8
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• 2019

The $Cu(In,Ga)Se_2$ (CIGS) thin film obtained by two-step process (metal deposition and Se annealing) has a rough surface morphology and many voids at the CIGS/Mo interface. To solve the problem a precursor that contains Se was employer by depositing a (In,Se)/(Cu,Ga) stacked layer. We devised a two-step annealing (vacuum pre-annealing and Se annealing) for the precursor because direct annealing of the precursor in Se environment resulted in the small grains with unwanted demarcation between stacked layers. After vacuum pre-annealing up to $500^{\circ}C$ the CIGS film consisted of CIGS phase and secondary phases including $In_4Se_3$, InSe, and $Cu_9(In,Ga)_4$. The secondary phases were completely converted to CIGS phase by a subsequent Se annealing. A void-free CIGS/Mo interface was obtained by the two-step annealing process. Especially, the CIGS film prepared by vacuum annealing $450^{\circ}C$ and subsequent Se annealing $550^{\circ}C$ showed a densely-packed grains with smooth surface, well-aligned bamboo grains on the top of the film, little voids in the film, and also little voids at the CIGS/Mo interface. The smooth surface enhanced the cell performance due to the increase of shunt resistance.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.2
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• pp.56-60
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• 2003

In this work, we have fabricated thin film resistors using the DC/RF magnetron sputter of 51wt%Ni-41wt%Cr-8wt%Si alloy target and studied the effect of the process parameters on the electrical properties. In fabrication process, sputtering power, substrate temperature and annealing temperature have been varied as controllable parameters. TCR decreases with increasing the substrate temperature, but TCR increases over 300 [$^{\circ}C$]. The films are annealed to 400 [$^{\circ}C$] in air atmosphere, TCR increases with increasing the annealing temperature. The resistivity was 172 [${\mu}{\Omega}{\cdot}cm$] and 209 [${\mu}{\Omega}{\cdot}cm$] for the RF and DC as a sputtering power sources, respectively. Also, TCR was -52 [$ppm/^{\circ}C$] and -25 [$ppm/^{\circ}C$]. As a results of them, it is suggested that the sheet resistance and TCR of thin films can be controlled by variation of sputter process parameter and annealing of thin film.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.31-34
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• 2003

Bi-2223 superconducting wires with 55 filaments were fabricated by stacking, drawing process with different heat-treatment histories. Two kinds of powders were prepared. One was pre-annealed at 760-820 $^{\circ}C$ and low oxygen partial pressure, and the other was only calcined state. Before rolling process, round wires were pre-annealed at 760 -820 $^{\circ}C$ and in a low oxygen partial pressure. We confirmed that pre-annealing step was to transform Bi-2212 orthorhombic structure from Bi-2212 tetragonal structure and to reduce the formation of second phases at superconducting wire. However Bi-2223 phases were formed at higher pre-annealing temperature. Bi-2223 conductor was needed frequently annealing at low temperature because pre-annealing at precursor powder brought about decrease in workability. We could achieve highest Je of 6500 A/$\textrm{cm}^2$ at the tape using Bi-2212 orthorhombic phase by introduced slightly overheating at the 1st sintering process.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.194-198
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• 2012

In this work, we studied the microstructural changes of ITO during the annealing process. ITO nanoparticles were prepared by the sol-gel method using indium tin hydroxide as the precursor. The prepared sample was investigated using TEM, powder XRD, XPS, DRIFT, and 2D correlation analysis. The O 1s XPS spectra suggested that the microstructural changes during the annealing process are closely correlated with the oxygen sites of the ITO nanoparticles. The temperature-dependent in situ DRIFT spectra suggested that In-OH in the terminal sites is firstly decomposed and, then, Sn-O-Sn is produced in the ITO nanoparticles during the thermal annealing process. Based on the 2D correlation analysis, we deduced the following sequence of events: 1483 (due to In-OH bending mode) ${\rightarrow}$ 2268, 2164 (due to In-OH stretching mode) ${\rightarrow}$ 1546 (due to overtones of Sn-O-Sn modes) ${\rightarrow}$ 1412 (due to overtones of Sn-O-Sn modes) $cm^{-1}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.466-467
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• 2005

Al doped zinc oxide films (ZnO:Al) were deposited on glass substrate by RF magnetron sputtering from a ZnO target mixed with 2 wt% $Al_2O_3$. The as-deposited ZnO:Al films were rapid-thermal annealed. Electrical properties and structural evolution of the films, as annealed by rapid thermal process (RTP), were studied and compared with the films annealed by conventional annealing process. RTP, the (002) peak intensity increases and the electrical resistivity decreases by 20%, after RT annealing. The effects of RT annealing on the structural evolution and electrical properties of RF sputtered films were further discussed and compared also with the films deposited by DC magnetron sputtering.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.382-389
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• 2019

A novel folding process is proposed using a repeated cold-die forging and annealing to form a sterling silver ring. Sterling silver plate was cut into a doughnut shape, and lattices with 0.43-mm line-width were imprinted on it. The sample was folded by forging using dies with slopes of $45^{\circ}$, $60^{\circ}$, and $75^{\circ}$ and annealing. For comparison, samples were also fabricated without annealing. Strain was identified by measuring the length of lattices. Vernier calipers, a Vickers hardness tester, an optical microscope, and a UV-VIS colorimeter were used to determine the size, hardness, microstructure, and body color. Without annealing, cracks occurred. However, successful deformation was possible when annealing was used. The results of macro strain measurements show that the outer diameter and width decreased, while the inner diameter and thickness increased after the final process. The maximum strain was increased 0.128 toward the parallel direction. The Vickers hardness decreased after annealing and increased after the folding process. The microstructure results showed that the grain size increased after annealing but decreased after folding. The color difference based on the Lab index was under 10 for all processes. Eventually, a doughnut-shaped silver plate was successfully deformed into a ring shape by the folding process.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.289.2-289.2
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• 2016

In-Ga-Zn-O(IGZO) receive great attention as a channel material for thin film transistors(TFTs) as next-generation display panel backplanes due to its superior electrical and physical properties such as a high mobility, low off-current, high sub-threshold slope, flexibility, and optical transparency. For the purpose of fabricating high performance IGZO TFTs, a thermal recovery process above a temperature of $300^{\circ}C$ is required for recovery or rearrangement of the ionic bonding structure. However diffused metal atoms from source/drain(S/D) electrodes increase the channel conductivity through the oxidation of diffused atoms and reduction of $In_2O_3$ during the thermal recovery process. Threshold voltage ($V_{TH}$) shift, one of the electrical instability, restricts actual applications of IGZO TFTs. Therefore, additional investigation of the electrical stability of IGZO TFTs is required. In this paper, we demonstrate the effect of Ti diffusion and modulation of interface traps by carrying out an annealing process on IGZO. In order to investigate the effect of diffused Ti atoms from the S/D electrode, we use secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy, HSC chemistry simulation, and electrical measurements. By thermal annealing process, we demonstrate VTH shift as a function of the channel length and the gate stress. Furthermore, we enhance the electrical stability of the IGZO TFTs through a second thermal annealing process performed at temperature $50^{\circ}C$ lower than the first annealing step to diffuse Ti atoms in the lateral direction with minimal effects on the channel conductivity.