• Journal of Korean Vacuum Science & Technology
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• 제4권2호
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• pp.50-54
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• 2000

We studied the synthesis of S $i_{1-x}$ Cx (x=0.016) epitaxial layer using ion implantation and solid phase epitaxy (SPE). The activation energy Ea was obtained for the loss of substitutional carbon using fourier transform-infrared spectroscopy (FTIR) and high-resolution x-ray diffraction (HR-XRD). In FTIR analysis, the integrated peak intensity was used to quantify the loss of carbon atoms from substitutional to interstitial sites during annealing. The substitutional carbon contents in S $i_{0.984}$ $C_{0.016}$ were also measured using HR-XRD. By dynamic simulations of x-ray rocking curves, the fraction of substitutional carbon was obtained. The effects of annealing temperature and time were also studied by comparing vacuum furnace annealing with rapid thermal annealing (RTA))))))

• 한국전기전자재료학회논문지
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• 제14권9호
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• pp.700-706
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• 2001

In this paper, I have fabricated and measured the gallium nitride(GaN) based Schottky diodes, and have carried out analyses of degradation of Schottky barrier characteristics. To improve of degraded Schottky barrier characteristics, I have carried out several experiments such as N$_2$ plasma exposure, annealing in N$_2$ ambient and annealing after N$_2$ plasma exposure. In the results of these experiments, I have achieved that only annealing in N$_2$ ambient is enough to improve the Schottky barrier characteristics, are temperature of 700$\^{C}$ and time of 90 sec in N$_2$ ambient furnace. for the analysis of these experiments, I have carried out the measurement of electric characteristics and quantitative analysis of etching damage using AES(Aguger Electron Spectroscopy).

• 대한전기학회논문지:전력기술부문A
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• 제49권12호
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• pp.589-594
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• 2000

The fuzzy controllers have been applied to the power system stabilizer due to its excellent properties on the nonlinear systems. But the design process of fuzzy controller requires empirical and heuristic knowledge of human experts as well as many trial-and-errors in general. This process is time consuming task. This paper presents an parameters tuning method of the fuzzy power system stabilizer using the genetic algorithm and simulated annealing(SA). The proposed method searches the local minimum point using the simulated annealing algorithm. The proposed method is applied to the one-machine infinite-bus of a power system. Through the comparative simulation with conventional stabilizer and fuzzy stabilizer tuned by genetic algorithm under various operating conditions and system parameters, the robustness of fuzzy stabilizer tuned by proposed method with respect to the nonlinear power system is verified.

• 한국표면공학회지
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• 제48권1호
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• pp.27-32
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• 2015

Advanced high strength steels undergo recrystallization annealing in reducing gas atmosphere before galvanizing to improve mechanical properties. The selective oxidations of elements such as Mn, Si, Cr and Al during annealing decrease wettability of liquid zinc, resulting in bare spots and other defects. In this work, Fe-3wt%Mn steel sheet was annealed at $780^{\circ}C$ for 1200 sec. in 5% $H_2-N_2$ atmosphere and then dipped into zinc bath held at $460^{\circ}C$, which contained 0.2wt% dissolved Al. MnO crystallines in the average size of 200 nm were formed on the surface after annealing. It is estimated that MnO has been detached into bath with the formation and growth of inhibition layer with longer immersion time during galvanizing. No evidence of aluminothermic reduction of MnO has been found in this study.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1424-1425
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• 2006

A four-step rapid thermal annealing (RTA) process is proposed in order to improve the throughput and stabilize the process, compared to the six-step RTA process. Effects of annealing on the properties of a structure mode of CMOS process in both cases were investigated. The implanted dopant(As, $BF_2$ and Ti/TiN) movement in silicon during different rapid thermal annealing conditions was studied using secondary ion mass spectroscopy (SIMS) technique. These results show that the four-step RTA process significantly improves time effect and throughput (15%) by the condition of ramping up compared to the six-step RTA process.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.861-864
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• 2000

Ferroelectric thin film capacitors with high dielectric constant are important for the application of memory devices. In this work, thin films of PLT(28)(Pb$\sub$0.72/La$\sub$0.28/Ti$\sub$0.93/O$_3$) were fabricated on Pt/Ti/SiO$_2$/Si substrates in-situ annealing and ex-situ annealing have been compared depending on the annealing time. We have systematically investigated the variation of grain sizes depending on the condition of post-annealing and the variation of deposition rate. C-V measurement, ferroelectric properties, leakage current and SEM were performed to investigate the electrical properties and the microstructural properties of Pb(La,Ti)O$_3$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.335-337
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• 1998

This paper presents a efficient algorithm for loss reduction of distribution system by automatic sectionalizing switch operation in distribution systems of radial type. Simulated Annealing can avoid escape from local minima by accepting improvements in cost, but the use of this algorithm is also responsible for an excessive computation time requirement. To overcome this major limitation of Simulated Annealing Algorithm, we may use advanced Simulated Annealing Algorithm. Numerical examples demonstrate the validity and effectiveness of the proposed methodology.

• 동력기계공학회지
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• 제18권4호
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• pp.66-71
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• 2014

In this study, effect of heat treatment on the microstructure and damping capacity of hot rolled magnesium alloys was investigated. The microstructure of hot rolled magnesium consisted of dendrite structure and $Mg_{17}Al_{12}$ compounds precipitated along the grain boundry. The dendrite structure was dissipated and $Mg_{17}Al_{12}$ compounds was decomposed by annealing treatment, and then they dissolved in ${\alpha}-Mg$. With an increasing the annealing temperature and time, damping capacity was slowly increased by the growth of grain size and decreasing of defects induced by hot rolling. Two kinds of magnesium alloys AZ 31 and AZ 61 after annealing showed no difference in damping capacity.

• 한국진공학회지
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• 제8권3A호
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• pp.218-223
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• 1999

We investigated the interfacial reactions between the $Y_2O_3$ film deposited by ICB processing and p-type (100) Si substrates upon annealing treatments in $O_2$ and Ar gas ambients. we also investigated the evolution of surface morphology of ICB deposited $Y_2O_3$ films upon annealing treatments. We observed that the root-mean-square(RMS) value of surface roughness measured by AFM increased with annealing time at $800^{\circ}C$ in $O_2$ ambient, while the change of surface roughness was not observed in Ar ambient. We also found the growth of $SiO_2$ layer and the formation of yttium silicate layer. From the capacitance values $(C_{acc})$ measured by C-V measurements, the relative didldctric constant of $Y_2O_3$ film in metal-insulator-semiconductor(MIS) structure was estimated to be about 9.

• 한국주조공학회지
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• 제40권5호
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• pp.129-133
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• 2020

The outcomes of solution annealing and stress corrosion cracking in cold-worked 316L austenitic stainless steel have been studied using x-ray diffraction (XRD) and the slow strain rate test (SSRT) technique. The good compatibility with a high-temperature water environment allows 316L austenitic stainless steel to be widely adopted as an internal structural material in light water reactors. However, stress corrosion cracking (SCC) has recently been highlighted in the stainless steels used in commercial pressurized water reactor (PWR) plants. In this paper, SCC and inter granular cracking (IGC) are discussed on the basis of solution annealing in a chloride environment. It was found that the martensitic contents of cold-worked 316L stainless steel decreased as the solution annealing time was increased at a high temperature. Moreover, mode of SCC was closely related to use of a chloride environment. The results here provide evidence of the vital role of a chloride environment during the SCC of cold-worked 316L.