• Progress in Superconductivity
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• v.5 no.2
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• pp.105-108
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• 2004

We have studied effects of in-situ annealing on the fabrication of superconducting MgB$_2$ thin films prepared by rf magnetron co-sputtering. The Films were deposited on A1$_2$O$_3$ (1102) substrates at room temperature by using Mg and B targets. To trap remnant $O_2$ gas in the chamber, we used 20 mtorr Af sputter-gas balanced with 5 mol % of H$_2$ gas. To enhance adhesion to the substrate a thin layer of B was deposited prior to the codeposition of Mg and B. After completion of the film deposition, an additional Mg layer was deposited on top to compensate for Mg loss during the subsequent in-situ annealing. We have investigated the effects of two most important annealing parameters that are the Mg-to-B composition ratio and the annealing temperature. The range of the Mg-to-B composition ratio was from 0.42 to 0.85, and that of the annealing temperature was 500 $^{\circ}C$∼750 $^{\circ}C$. The Best result was obtained for the composition ratio of about 10% Mg excess from the stoichiometry and the annealing temperature of 700 $^{\circ}C$. Based on these results, we obtained films with T$_{c}$ : 36.5 K by further refining the fabrication process.s.

• Journal of the Korean Vacuum Society
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• v.16 no.5
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• pp.343-347
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• 2007

Fe thin films exhibited (100) preferential orientation when they were deposited at low deposition rate of $0.1{\AA}/s$ on glass substrates by using facing target sputtering system. The (100) oriented Fe layer induces (100) orientation of Pt layer deposited on it owing to hetero-epitaxial growth. After annealing at $600^{\circ}C$ in $H_2$ atmosphere, FePt films exhibited f.c.t. (001) texture in the whole film caused by inter-diffusion between atoms. We have also confirmed that the homogeneously inter-diffused compositional modulation in the film after the annealing process. Furthermore, annealing process in $Ar+H_2$ atmosphere at $400^{\circ}C$ during Pt deposition was effective for attaining Pt (100) texture. The annealing process during Pt deposition also induced in low annealing temperature and decreased annealing time for attaining the FePt f.c.t. (001) structure.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.403-403
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• 2011

결정질 태양전지는 태양전지 시장에 큰 서막을 장식하였다. 현재 여러 종류의 태양전지 기술들이 많이 나오고 있지만 결정질 태양전지는 변환 효율이 좋고 신뢰성이 높아서 높은 시장 점유율을 차지하고 있다. 하지만 응용 분야가 적고 기판 가격이 비싸다는 단점이 있다. 현재에는 응용분야 개선을 위하여 Flexible solar cell에 대한 연구가 활발하다. Flexible solar cell에 상부전극은 결정질 태양전지에서 사용되는 Ag나 Al 전극 대신 TCO 종류의 일종인 ITO를 많이 사용한다. Flexible Solar cell은 Organic Solar cell과 Amorphous Solar Cell 두 가지 범주를 가지고 있다. 본 연구에서는 Amorphous Solar Cell의 전극에 사용되는 ITO의 온도 Stress에 따른 특성을 연구함으로써 Engineer의 근본적인 이슈인 저비용, 고효율에 초점을 맞추어 소자특성을 확인해 보도록 한다. Glass에 E-beam evaporation 장비를 이용하여 ITO를 증착하였고 제작된 소자를 200, 250, 300, 350$^{\circ}C$의 온도변수를 두어 1시간동안 Annealing 하였다. 각 Annealing 온도에 따른 Sheet resistivity,와 visible 영역의 transmittant를 측정하였다. visible영역에서의 transmittant는 Annealing 200$^{\circ}C$에서 300$^{\circ}C$로 온도가 증가함에 따라 transmittant는 증가하다가 350$^{\circ}C$에서 감소하였다. Sheet resistivity의 경우 Annealing 200$^{\circ}C$에서 300$^{\circ}C$로 온도가 증가함에 따라 ITO의 Sheet resistivity가 줄어들다가 350$^{\circ}C$에서 증가하였다. 300$^{\circ}C$로 Annealing한 ITO가 가시광선 영역에서 transmittant가 가장 높은 80%로 측정 되었다. Sheet resistivity역시 300$^{\circ}C$로 Annealing한 ITO가 8${\Omega}/{\Box}$로 가장 낮았다. Annealing 온도가 ITO의 electrical 특성과 optical 특성에 변화를 주었음을 알 수 있었다. Resistivity가 낮은 ITO 전극으로 박막 셀을 제작한다면 좋은 효율을 얻을 수 있을 거라 생각된다.

• Journal of the Korean Society for Heat Treatment
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• v.33 no.1
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• pp.13-19
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• 2020

Annealing effects on the properties of Bi-doped ZnO thin films were investigated. Bi- doped ZnO thin films were deposited on quartzs substrates at 300℃ by using radio-frequency magnetron sputtering system. Post heat treatments at 600, 700, and 800℃ were performed to evaluate the effect of annealing temperatures on the structural, optical, and electrical properties of Bi-doped ZnO thin films. FE-SEM images showed the dramatic surface morphology changes by rearrangement of elements at high heat treatment temperature of 800℃. X-ray diffraction analysis indicated that the peaks of the Bi-doped ZnO thin films were same as the peaks of the (002) planes of ZnO peak-positioned at 2θ=34.0° and peak intensities and FWHMs were improved as the annealing temperatures increased. The optical transmittance was improved with increasing annealing temperatures and was over 80% in the wavelength region between 435 and 1100 nm at the annealing temperature of 700 and 800℃. With increasing annealing temperature, the electron concentrations and electron mobilities were increased. On the other hand, electric resistivity of the films were decreased with increasing annealing temperatures. These results showed that the heat treatment temperature is an important parameter to improve the structural, optical, and electrical properties of Bi-doped ZnO thin films.

• Korean Journal of Materials Research
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• v.28 no.9
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• pp.534-538
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• 2018

The annealing characteristics of a cold rolled Al-6.5Mg-1.5Zn alloy newly designed as an automobile material is investigated in detail. The aluminum alloy in the ingot state is cut to a thickness of 4 mm, a total width of 30 mm and a length of 100 mm and then reduced to a thickness of 1 mm (reduction of 75 %) by multi-pass rolling at room temperature. Annealing after rolling is performed at temperatures ranging from 200 to $400^{\circ}C$ for 1 hour. The tensile strength of the annealed material tends to decrease with the annealing temperature and shows a maximum tensile strength of 482MPa in the material annealed at $200^{\circ}C$. The tensile elongation of the annealed material increases with the annealing temperature, while the tensile strength does not, and reaches a maximum value of 26 % at the $350^{\circ}C$ annealed material. For the microstructure, recovery and recrystallization actively occur as the annealing temperature increases. The recrystallization begins to occur at $300^{\circ}C$ and is completed at $350^{\circ}C$, which results in the formation of a fine grained structure. After the rolling, the rolling texture of {112}<111>(Cu-Orientation) develops, but after the annealing a specific texture does not develop.

• Transactions of Materials Processing
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• v.31 no.5
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• pp.273-280
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• 2022

Although the mechanical properties of high-entropy alloys depend on the annealing conditions, limited works were established to investigate the annealing effect on the mechanical properties of Mo-added high-entropy alloys. Therefore, in the present work, the annealing effects on the microstructural evolution and mechanical properties of Mo-added high-entropy alloy were investigated. As a result, incomplete recrystallization from the limited annealing time not only suppresses deformation-induced phase transformation during cryogenic tensile test but also induces a deformation instability that results into the ductility reduction compare with the fully recrystallized sample. This result represents adjustment of annealing time is useful to control both transformation-induce plasticity and deformation instability of high-entropy alloys, and this can be applied to control the mechanical properties of metallic alloys by combining pre-straining and subsequent annealing.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.1
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• pp.47-52
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• 2024

The effects of annealing temperature on the optical and electrical properties of BZO thin films, grown on glass substrate, have been investigated. Analysis of the XRD shows that regardless of the annealing temperature, all BZO thin films indicate the c-axis orientation. The full width of half maximum (FWHM) decreases from 1.65 to 1.07° as the annealing temperature increases from 400 to 600℃. The average transmittance in the visible light region showed a high value of 85% without significantly affecting the annealing temperature. The results of Hall effect measurements indicate that the carrier concentration and mobility increased and the resistivity decreased as the annealing temperature increased. The resistivity and the carrier concentration of the BZO thin films annealed 600℃ were 9.75×10^-2 Ω·cm and 4.21×10¹⁹ cm^-3 respectively, showing the best value. The optimization of deposition and annealing conditions will certainly make the BZO thin films promising materials for the application to the next generation of optoelectronic devices.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.779-780
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• 2012

• Transactions on Electrical and Electronic Materials
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• v.15 no.5
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• pp.253-256
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• 2014

$Pb(Zr_{0.52}Ti_{0.48})O_3$ thin films of $1.5{\mu}m$ thickness were grown on $Pt/Ti/Gd_3Ga_5O_{12}$ substrate by RF magnetron sputtering at annealing temperatures ranging from $550^{\circ}C$ to $700^{\circ}C$. We evaluated the residual stress, by using a William-Hall plot, as a function of the annealing temperatures of PZT thin film with a constant thickness. As a result, the residual stresses of PZT thin film of $1.5{\mu}m$ thickness were changed by varying the annealing temperature. Also, we measured the hysteresis characteristic of PZT thin films of $1.5{\mu}m$ thickness to evaluate for application of an optoelectronic device.

• Korean Journal of Materials Research
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• v.15 no.4
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• pp.252-256
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• 2005

We removed the bluish of the natural ruby successfully by vacuum annealing, and measured the color evolution with annealing time and temperature. We varied the anneal temperature and time $800\~1500^{\circ}C$ and $3\~26$ hrs, respectively. The color evolution of rubies with annealing condition was recorded by a digital camera and a color coordination visible spectrometer. We determined the optimum bluish eliminating annealing condition was $1500^{\circ}C-3hr$, which conserving the natural inclusions. We suggest the bluish shrink with diffusion coefficient of $D=(5\times10^{-3}){\exp}(-200.000/RT)[cm^2/s]$. We propose the color of ruby may be determined as the identical red color if the color difference between two samples are less than 1.0, and the color difference nay be an auxiliary standard to evaluate the color of rubies.