• Journal of the Korean Society for Heat Treatment
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• v.31 no.2
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• pp.56-62
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• 2018

Many researchers have studied on the precipitation control after solution treatment to improve the damping capacity without decreasing the strength. However, studies on the damping capacity and microstructure changes after deformation in the solid solution strengthening alloys were inadequate, such as the Al-Zn series magnesium alloys. Therefore, in order to investigate the effect of annealing condition on microstructure change and damping a capacity of AZ61 magnesium alloy. In this study, it was confirmed that the microstructure changes affect the damping capacity and hardness when annealed AZ61 alloy. AZ61 magnesium alloy was rolled at $400^{\circ}C$ with rolling reduction of 30%. These specimens were annealed at $350^{\circ}C$ to $450^{\circ}C$ for 30-180 minutes. After annealing, microstructure was observed by using optical microscopy, and damping capacity was measured by using internal friction measurement machine. Hardness was measured by Vickers hardness tester under a condition of 0.3 N. In this study, static recrystallization was observed regardless of the annealing conditions. In addition, uniform equiaxed grain structure was developed by annealing treatment. Hardness is decreased with increasing grain size. This is associated with Hall-Petch equation and static recrystallization. In case of damping capacity, bigger grain size show the larger damping capacity.

• Korean Journal of Materials Research
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• v.22 no.1
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• pp.24-28
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• 2012

$In_2O_3$ films were deposited by RF magnetron sputtering on a glass substrate and then the effect of post deposition annealing in nitrogen atmosphere on the structural, optical and electrical properties of the films was investigated. After deposition, the annealing process was conducted for 30 minutes at 200 and $400^{\circ}C$. XRD pattern analysis showed that the as deposited films were amorphous. When the annealing temperature reached 200-$400^{\circ}C$, the intensities of the $In_2O_3$ (222) major peak increased and the full width at half maximum (FWHM) of the $In_2O_3$ (222) peak decreased due to the crystallization. The films annealed at $400^{\circ}C$ showed a grain size of 28 nm, which was larger than that of the as deposited amorphous films. The optical transmittance in the visible wavelength region also increased, while the electrical sheet resistance decreased. In this study, the films annealed at $400^{\circ}C$ showed the highest optical transmittance of 76% and also showed the lowest sheet resistance of $89{\Omega}/\Box$. The figure of merit reached a maximum of $7.2{\times}10^{-4}{\Omega}^{-1}$ for the films annealed at $400^{\circ}C$. The effect of the annealing on the work-function of $In_2O_3$ films was considered. The work-function obtained from annealed films at $400^{\circ}C$ was 7.0eV. Thus, the annealed $In_2O_3$ films are an alternative to ITO films for use as transparent anodes in OLEDs.

• Journal of the Korean Society for Heat Treatment
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• v.29 no.4
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• pp.163-167
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• 2016

$SnO_2$ thin films were prepared by radio frequency magnetron sputtering on glass substrates and then vacuum annealed for 30 minutes at 100, 200, and $300^{\circ}C$, respectively. The thickness of films kept at 100 nm by controlling the deposition rate. While the optical transmittance and electrical resistivity of as deposited $SnO_2$ films were 82.6% in the visible wavelength region and $1.9{\times}10^{-3}{\Omega}cm$, respectively, the films annealed at $200^{\circ}C$ show the increased optical transmittance of 84.5% and the electrical resistivity also decreased as low as $8.5{\times}10^{-4}{\Omega}cm$. From the observed results, it is concluded that post-deposition vacuum annealing at $200^{\circ}C$ is an attractive condition to optimize the opto-elecrtical properties of $SnO_2$ thin films for the opto-electrical applications.

• Electrical & Electronic Materials
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• v.8 no.4
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• pp.458-463
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• 1995

The optical and electrical properties of $C_{22}$-Quinolinium(TCNQ) Langmuir-Blodgett films have been studied depending on the annealing temperatures. The optimal properties were investigated using UV/visible(300-800[nm]) absorption spectra and FTIR(Fourier-transformed- infrared) absorption measurements. The electrical properties were investigated in a frequency range of 10[Hz]-13[MHz]. The UV/visible absorption spectra at room temperature show that there are four characteristic peaks at 320, 380, 494 and 678[nm]. These absorption peaks decrease very rapidly above the annealing temperature of 180[.deg. C], which is due to a structural change of TCNQ. The FTIR absorption measurements strongly support the result of the UV/visible absorption spectra, because the absorption peak of TCNQ- at 2181[$cm^{-1}$ /] also decreases above 140[.deg. C]. The frequency-dependent dielectric constant shows that there is a dielectric dispersion near 1[MHz] which is due to an orientational polarization of the molecules inside the film. The overall frequency-dependent dielectric constant is higher near 80[.deg. C]. It may be due to a softness of the alkyl chains.s.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.60-60
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• 2010

1-D nanostructured materials have much more attention because of their outstanding properties and wide applicability in device fabrication. Bismuth oxide($Bi_2O_3$) is an important p-type semiconductor with main crystallographic polymorphs denoted by $\alpha-$, $\beta-$, $\gamma-$, and $\delta-Bi_2O_3$[1]. Due to its unique optical and electrical properties, $Bi_2O_3$ has been extensively investigated for various applications in gas sensors, photovoltaic cells, fuel cells, supercapacitors[2-4]. In this study, $Bi_2O_3$ NWs were grown by two step annealing process: in the first step, after annealing at $270^{\circ}C$ for 10h in a vaccum($3{\times}10^{-6}$ torr), we can obtain the bismuth nanowires. In the second step, after annealing at $300^{\circ}C$ for 2h in $O_2$ ambient, we successfully fabicated $Bi_2O_3$nanowires.

• Journal of Surface Science and Engineering
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• v.29 no.6
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• pp.666-672
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• 1996

The optical property of CdTe thin film is important for applications such as the compound semiconductor type solar cells. CdTe films are prepared by RF sputtering at various substrate temperature between $25^{\circ}C$ and $300^{\circ}C$, then, annealed in argon gas environment at $400^{\circ}C$. The annealing process of the thin film caused variation in the film structure and the composition of films. The deformation of CdTe thin film was observed by X-ray diffractometry. After annealing, the grain size increased and the portion of the non-crystalline CdTe reduced. Futhermore, the structure of sputtered CdTe film grown at the substrate temperature more than $250^{\circ}C$ was enhanced in the (111) direction of zincblend structure. There was a discrepancy, in the spectroscopic ellipsometer spectrum, between the single crystal CdTe and the sputtered CdTe thin films, especially in the region over 3.2eV. An oxidation layer was found on the CdTe thin film by spectroscopic ellipsometry analysis.

• Electrical & Electronic Materials
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• v.10 no.10
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• pp.1005-1010
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• 1997

ZnS:Mn thin film was made by coevaporation with Electron Beam Evaparation(EBE) method. And structural and optical characteristics of ZnS:Mn thin films were investigated by substrate temperature annealing temperature and dopant Mn. When ZnS:Mn thin film was well deposited with cubic crystalline at substrate temperature of 30$0^{\circ}C$ its surface index was [111] and its lattice constant of a was 5.41$\AA$. Also When ZnA:Mn thin film was well made with hexagonal crystalline at substrate temperature of 30$0^{\circ}C$annealing temperature of 50$0^{\circ}C$and annealing time of 60min its miller indices were (0002) (1011), (1012) and (1120). And its lattice constant of a and c was 3.88$\AA$and 12.41$\AA$ respectively. Finally hexagonal ZnS:Mn thin film with dopant Mn of 0.5wt% had fundamental absorption wavelength of 342nm. And so its energy bandgap was about 3.62eV.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1301-1304
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• 1994

ZnO transparent conducting oxide thin films have been prepared by Pyrosol deposition method. The effect of the Al doping with varying Al/Zn mole ratio and the post-deposition heat treatment on the electrical resistivity and optical transmittance of the prepared films have been investigated. From the experimental results, the ZnO:Al thin films with resistivity as low as $3{\times}10^{-3}{\Omega}cm$ and transmittance as high as 80% can be obtained by Al doping. Also We have found the annealing of the as-deposited ZnO film in vacuum leads to a substantial reduction in resistivity without affecting the optical transmittance and crystallographic orientation. However, the annealing effect of ZnO:Al thin films is smaller than ZnO films with respect to reduction in resistivity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.446-447
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• 2007

The rapid thermal annealing effect of transparent IZTO(indium zinc oxide) and IAZO(indium alminium zinc oxide) films grown on glass substrate for solar cell or flat panel displays(FPDs) was studied. We prepared IZTO using RF magnetron sputtering and IAZO using DC co-sputtering method. Subsequently, using rapid thermal annealing(RTA) system, prepared IZTO and IAZO films were annealed at 300, 400, 500, $600^{\circ}C$ for 90sec. In addition, Electrical and optical characteristics were measured by Hall effect measurement and UV/Vis spectrometer examinations, respectively. To analyze structural properties and surface smoothness of the IZTO and IAZO films, XRD and SEM examinations were performed, respectively. It was shown that IZTO and IAZO films exhibited microcrystalline structure over $400^{\circ}C$ and amorphous structural regardless of RTA temperature, respectively.

• Journal of the Korean Society for Heat Treatment
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• v.30 no.1
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• pp.1-5
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• 2017

A 100 nm thick $SnO_2$ thin films were prepared by radio frequency magnetron sputtering on glass substrates and then annealed in nitrogen atmosphere for 30 minutes at 100, 200, and $300^{\circ}C$, respectively. While the visible light transmittance and electrical resistivity of as deposited $SnO_2$ films were 81.8% and $1.5{\times}10^{-2}{\Omega}cm$, respectively, the films annealed at $200^{\circ}C$ show the increased optical transmittance of 82.8% and the electrical resistivity also decreased as low as $4.3{\times}10^{-3}{\Omega}cm$. From the observed results, it is concluded that post-deposition annealing in nitrogen atmosphere at $200^{\circ}C$ is an attractive condition to optimize the optical and electrical properties of $SnO_2$ thin films for the various display device applications.