• Journal of the Korean institute of surface engineering
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• v.25 no.6
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• pp.293-298
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• 1992

Various vanadium-oxide thin films were deposited by e-beam and thermal evaporation of V2O5, V2O3, and VO2 powders. Films with thickness of $2000\AA$ were subjected to annealing at $300^{\circ}C$~$450^{\circ}C$ in N2 atmosphere for the crystallization and desification purposes. For the films deposited from V2O5 and VO2 sources, sources, Magneli (VnO2n-1$ 4\leq$ $n\leq$ 8) and VO2 phase appeared at $300^{\circ}C$, respectively, but VO2 phase also transformed into Magneli phase at $450^{\circ}C$ by severe reduction. On the contrary, VO2/VO mixed phases resulted from congruent evaporation of V2O3 unchanged after the same annealing treatment due to the balanced reduction and oxidation of VO2 and VO whcih have different equilibrium O2 pressures. It is suggested that the annealing in the controlled oxidation atmosphere or the deposition using mixed oxide sources are necessary to get the film containing VO2 phase.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.366-369
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• 1999

Synthetic diamond films have been deposited on the silicon(100) surface and molybdenum substrates using an microwave plasma enhanced vapor deposition (MWPECVD) method. The effect of deposition time, surface morphology, X-ray diffraction pattrm, infrared transmittance and Raman Scattering have been studied, The diamond film deposited on Mo substrate for (100) hours at 40 torr H$_2$-CH$_4$O$_2$ gas system have been shown 1${\mu}{\textrm}{m}$/h of growth rate and good crystallization

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.74-77
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• 2004

Porous membranes were prepared via thermally induced phase separation (TIPS) of (ethylene-co-vinyl alcohol) (EVOH)/glycerol mixtures. The liquid-liquid (L-L) phase boundaries are shifted to higher temperature when the ethylene contents in EVOH increase. Moreover, the kinetic study proved that the growth of droplets formed by the general liquid-liquid (L-L) phase separation obeyed a power-law scaling relationship in the later stage of spinodal decomposition (SD). A new phase separation mechanism was presented, in which the L-L phase separation could be resulted from the crystallization. The hollow fiber membranes were prepared. The membranes showed asymmetric structures with skin layer near the outer surface, the larger pores just below the skin layer and the smaller pores near the inner surface. The effect of ethylene content (EC) in EVOH, cooling water bath temperature and take-up speed on membrane performance was investigated.

• Journal of the Korean Ceramic Society
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• v.44 no.7
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• pp.358-361
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• 2007

Well-ordered mesoporous SiCBN ceramics have been successfully synthesized by infiltrating a polymeric precursor, which was prepared from borazine and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane via a hydroboration reaction, into a mesoporous carbon (CMK-3) as a hard template. This was followed by pyrolysis at $1400^{\circ}C$ under nitrogen gas and subsequent oxidative removal of the carbon template without chemical etching. The prepared mesoporous SiCBN ceramic was characterized by a small-angle XRD, TEM, and BET surface area. The resulting mesoporous SiCBN ceramic revealed a BET surface area of $275 m^2g^{-1}$ and a pore volume of $0.8 cm^3 g$ with no crystallization.

• Journal of the Korean institute of surface engineering
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• v.23 no.4
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• pp.208-217
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• 1990

Electroless Ni-Cu-P plating was performed was performed to investigate for plating and changes in microhardness and corrosion rate of of electroless deposits depending on heat treatment. The activation energy for $75~85^{\circ}C$ were calculated to be 66.7KJ/mole. Plating rate increased to 34% with addition of 200ppm of NaF and 0.8ppm of thiourea to the bath. The highest hardness value was obtained by heat treatment deposits layer at$ 400^{\circ}C$, 1 hour. The increase in hardness of deposits by heating was confirmed to be associated with crystallization of the amorphous deposits. Corrosion resistance of deposir layer, which had been heated up to $300^{\circ}C$, was found to be exellent when immersed in 1N-H2SO4 solution, Change of the corrosion resistance seems to have some important bearing on content of amorpous, Ni3P and Cu3P.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.118-119
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• 2007

Phase stability and morphological investigation on the $Si/SiO_2/HfO_2$ and $Si/SiO_2/ZrO_2$ stack are presented. Thermal stability of $HfO_2$ and $ZrO_2$ determines the quality of interface and subsequently the performance of device. The stacks have been fabricated and annealed at $1000^{\circ}C$ for various time. In evolution of crystalline phase and morphology (electrical and geometrical) of high-k materials, annealing time and process are observed to be crucial factors. The crystallization of some phase has been observed in the case of $Si/SiO_2/HfO_2$. The chemical environment around Zr and Hf in respective samples is observed to be different.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.89-95
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• 2001

The fretting wear characteristics of Zircaloy-4 tube at room and high temperature were Investigated experimentally. In this study, the number of cycles, slip amplitude and temperature were selected as main factors of fretting wear. The results of this research showed that the wear volume Increased with the Increase of slip amplitudes and the number of cycles but decreased with temperature and the coefficient of friction were observed different tendency between room and high temperature. According to SEM(EDS) only gross slip were observed on the surface of both specimens and compacted oxide were on worn surfaces. XRO patterns showed that the crystallization of ZrO$_2$ were observed on the worn surface at high temperature. The fretting wear were Investigated due to oxidation and accumulation of plastic flow.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.157-158
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• 2007

Tin oxide films were successfully crystallized without additional heating by inductively coupled plasma assisted chemical vapor deposition (ICP-CVD). The degree of crystallization was affected by the ICP power, hydrogen flow and ion bombardment induced by negative substrate bias. The substrate temperature was increased only up to $150^{\sim}180^{\circ}C$ by plasma heating, which suggests that the formation of $SnO_2$ crystalswas caused by enhanced reactivity of precursors in high density plasma. The hardness of deposited tin oxide films ranged from 5.5 to 11GPa at different hydrogen flow rates.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.343-345
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• 2012

대향 타겟 스퍼터링법 (Facing Targets Sputtering)을 이용하여 저온 공정에서 ZnO 박막을 증착하였다. 이 실험에서 두 개의 타겟의 거리를 110nm로 고정하고 박막의 증착두께를 150nm로 정하였다. 산소 가스의 유량, 인가 전력을 변수로 하였을 경우 ZnO 박막의 방향성과 결정성을 XRD로 측정하고 분석하였다. 그 결과 인가전압과 산소 유량의 증가에 따라 결정성은 좋아진다.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.2
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• pp.84-87
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• 2002

The Si$_{1-x}$ Gex/Si surface alloy (x = 0.3, 0.4 and 0.5), which are prepared by solid source MBE and have the SiGe epilayer thickness of 50$\AA$, are annealed with different parameters. The surface structure analyses of the heterostructure samples are made on a triple-axis X-ray diffractometer in grazing incidence X-ray diffraction (GIXRD) geometry. It has been found that with different annealing time (1.5h, 18h, 64h) and annealing temperature (550 $^{\circ}C$, 750 $^{\circ}C$), the SiGe epilayer experienced different strain relaxation process, which was deduced from the GIXRD measurements of the in-plane (220) diffraction peak of Si(001) substrate and the relevant (220) surface diffraction of SiGe epilayer. The results show that the stress relieving and the lateral strain relaxation in the SiGe/Si heterostructure can be promoted by correct annealing, which is very helpful for the preparation of SiGe/Si strained superlattice with fine strain crystallization..