• 한국주조공학회지
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• 제27권4호
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• pp.179-183
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• 2007

The TiC layer was formed on Ti and Ti alloys by plasma carburizing method. The main experimental parameters for plasma car boozing were temperature and time. XRD, EDX, hardness test and corrosion test were employed to analyze the evolution and material properties of the layer. The preferred orientation of TiC layers is (220) at treated temperature of $700^{\circ}C\;and\;880^{\circ}C$ However, it is changed to (200) at temperature of $800^{\circ}C$ The thickness of carbide layer increase with increasing carburizing temperature. Highest hardness of hardened layer formed on CP-Ti was obtained at the carburizing condition of processing temperature $880^{\circ}C$ and processing time 1080min. The corrosion potential of carburizing specimen was higher than untreated CP-titanium, and corrosion potential increased as carburizing temperature and time increased. Thus the corrosion resistance of CP-Ti was greatly enhanced after plasma carburizing treatment.

• 반도체디스플레이기술학회지
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• 제16권2호
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• pp.55-60
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• 2017

The supercritical $CO_2$ (sc-$CO_2$) mixture and the sc-$CO_2$-based Photoresist(PR) stripping(SCPS) process were applied to the removal of the post etch/ash PR residue on aluminum patterned wafers and the results were observed by scanning of electron microscope(SEM). In the case of MDII wafers, the carbonized PR was able to be effectively removed without pre-stripping by oxygen plasma ashing by using sc-$CO_2$ mixture containing the optimum formulated additives at the proper pressure and temperature, and the same result was also able to be obtained in the case of HDII wafer. It was found that the efficiency of SCPS of ion implanted wafer improved as the temperature of SCPS was high, so a very large amount of MEA in the sc-$CO_2$ mixture could be reduced if the temperature could be increased at condition that a process permits, and the ion implanted photoresist(IIP) on the wafer was able to be removed completely without pre-treatment of plasma ashing by using the only 1 step SCPS process. By using SCPS process, PR polymers formed on sidewalls of metal conductive layers such as aluminum films, titanium and titanium nitride films by dry etching and ashing processes were removed effectively with the minimization of the corrosion of the metal conductive layers.

• 구강회복응용과학지
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• 제25권4호
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• pp.361-374
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• 2009

임플란트와 골 반응을 개선하기 위한 생화학적 표면 처리 방법으로 다양한 이온을 이용한 이온주입법에 대한 관심이 높아지고 있다. 본 연구는 플라즈마 상태의 마그네슘 이온을 임플란트 표면에 주입하여 이온 피막을 형성하는 방법으로 표면 처리를 한 임플란트에 대한 MC3T3-E1 골모양 세포의 초기 반응을 평가해 보고자 하였다. 티타늄 디스크를 네 가지 군으로 표면처리를 달리하였다. A군은 연마만 하였고 B군은 연마 후 마그네슘 이온을 주입하였다. C군은 알루미늄 입자분사 하였고, D군은 알루미늄 입자분사 후 마그네슘 이온을 주입하였다. 조골세포의 반응을 세포 부착, 증식, 분화의 단계별로 평가하였다. 세포 부착을 평가하기 위해 MC3T3-E1 골모양 세포를 4시간, 24시간, 48시간 금속 표면에서 배양하여 주사현미경으로 관찰하였다. 세포분화도평가는 세포를 4일간 배양 후 알칼리성 인산분해효소 활성도 분석을 통해 시행하였다. 세포외기질의 세포내 발현은 RT-PCR을 통해 평가하였다. 이상의 실험에서 다음과 같은 결과를 얻었다. 1. 주사현미경 관찰시 시간의 흐름에 따라 세포 부착량은 증가하였으며, 마그네슘 이온을 주입한 시편에서 더 많은 양 세포 증식이 관찰되었으며 분화정도도 더 높은 것으로 관찰되었다. 2. RT-PCR 분석시 알루미늄 입자분사 후 마그네슘 이온을 주입한 시편에서 c-fos와 osteonectin의 발현이 증가된 소견을 보였다. 3. 알칼리성 인산분해효소 활성도 분석시 금속 표면처리 방법에 따른 차이는 발생하지 않았다. 이상의 결과를 종합하면 Mg 이온이 주입된 군의 세포가 Mg 이온이 주입되지 않은 군보다 초기의 세포반응이 더 우수하다는 것을 알 수 있다.

• 한국진공학회지
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• 제7권s1호
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• pp.100-105
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• 1998

This paper describes the preparation of Pt-and $TiO_2$-doped $Nb_2O_5$ thin film by Ion-Beam-Enhanced Deposition. Platinum and titanium doping, and Nb2O5 deposition were carried out in situ. The dependence of oxygen sensing properties on the amounts of Pt and Ti dopant in the $Nb_2O_5$ film was investigated. There were the highist sensitivity, the lowest temperature coefficient and the shortest responce time at doping of 5 mol% $TiO_2$ and 0.3 mol%Pt

• 한국세라믹학회지
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• 제39권5호
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• pp.433-437
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• 2002

Impact-collision ion scattering spectroscopy was applied to study the geometrical structure of epitaxially grown TiO layers on the MgO(100) surface. Hetero-epitaxial TiO layer was formed by thermal evaporation of titanium onto the MgO(100) surface followed by the exposure to oxygen at $400{\circ}$. The well-ordered TiO structure was confirmed by the impact-collision ion scattering spectroscopy and reflection high energy electron diffraction patterns. It is revealed that the Ti and O atoms are located on the on-top site of the MgO(100) surface and the TiO overlayers are composed of little three dimensional islands.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.285-286
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• 2006

Magnesium is the lightest of all the structural metals having density of 1.74. It is approximately 2/3 lighter than aluminium, l/4 lighter than titanium alloy and 1/5 lighter than iron. Among the light-weight alloys, magnesium and its alloys show a good possibility for high performance aerospace and automotive applications, however the widespread use of magnesium alloys has been limited mainly by its poor oxidation and corrosion resistance. In this work, corrosion-resistive thin films were prepared onto the magnesium alloy substrate(AZ91D) by environmental friendly coating technique, ion plating method. And their corrosion protection mechanism were analyzed.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.17-17
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• 2002

Time-of-flight impact collision ion scattering spectroscopy (TOF-ICISS) was applied to study the geometrical structure of the epitaxially grown BaTiO₃ layers on the MgO(100) surface. Hetero-epitaxial BaTiO₃ layers can be deposited by the following steps: first thermal evaporation of titanium onto the MgO(100) surface in the atmosphere of oxygen at 400℃, secondly thermal evaporation of barium in the same manner, and finally annealing at 800℃. Well ordered perovskite BaTiO₃ was confirmed from the ICISS spectra and reflection high electron energy diffraction (RHEED) patterns. It was also revealed that BaTiO₃ had cubic structure with the same lattice parameter of bulk phase.

• 대한전자공학회논문지SD
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• 제39권5호
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• pp.1-7
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• 2002

Deep sub-micron bulk CMOS circuits require gate electrode materials such as metal silicide and titanium silicide for gate oxides. Many authors have conducted research to improve the quality of the sub-micron gate oxide. However, few have reported on the electrical quality and reliability of an ultra-thin gate. In this paper, we will recommend a novel shallow trench isolation structure and a two-step TiS $i_2$ formation process to improve the corner metal oxide semiconductor field-effect transistor (MOSFET) for sub-0.1${\mu}{\textrm}{m}$ VLSI devices. Differently from using normal LOCOS technology, deep sub-micron CMOS devices using the novel shallow trench isolation (STI) technology have unique "inverse narrow-channel effects" when the channel width of the device is scaled down. The titanium silicide process has problems because fluorine contamination caused by the gate sidewall etching inhibits the silicide reaction and accelerates agglomeration. To resolve these Problems, we developed a novel two-step deposited silicide process. The key point of this process is the deposition and subsequent removal of titanium before the titanium silicide process. It was found by using focused ion beam transmission electron microscopy that the STI structure improved the narrow channel effect and reduced the junction leakage current and threshold voltage at the edge of the channel. In terms of transistor characteristics, we also obtained a low gate voltage variation and a low trap density, saturation current, some more to be large transconductance at the channel for sub-0.1${\mu}{\textrm}{m}$ VLSI devices.

• 한국세라믹학회지
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• 제43권1호
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• pp.62-67
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• 2006

Time-of-flight impact-collision ion scattering spectroscopy (TOF-ICISS) using 2 keV $He^+$ ion was applied to study the geometrical structure of the $BaTiO_3$ thin film which was grown on the MgO(100) surface. Hetero-epitaxial $BaTiO_3$ layers were formed on the MgO(100) surface by thermal evaporation of titanium followed first by oxidation at $400^{\circ}C$, subsequently by barium evaporation, and finally by annealing at $800^{\circ}C$. The atomic structure of $BaTiO_3$ layers was investigated by the scattering intensity variation of $He^+$ ions on TOF-ICISS and by the patterns of reflection high energy electron diffraction. The scattered ion intensity was measured along the <001> and <011> azimuth varying the incident angle. Our investigation revealed that perovskite structured $BaTiO_3$ layers were grown with a larger lattice parameter than that of the bulk phase on the MgO(100) surface.

• 한국진공학회지
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• 제4권S2호
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• pp.40-48
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• 1995

$TiB_2$-TiN double-layer coating have been prepared by ion beam enhanced deposition. AES, XRD, TEM and HRTEM were employed to characterize the $TiB_2$ layer. The microhardness of the coatings was evaluated by an ultra low-load microhardness indenter system, and the tribological behavior was examined by a ball-on-disc tribology wear tester. It was found that in a single titanium diboride layer, the composition is uniform along the depth of the film, and it is mainly composed of nanocrystalline $TiB_2$ with hexagonal structure, which resulted from the ion bombardment during the film growth. The hardness of the $TiB_2$ films increases with increasing ion energy, and approaches a maximum value of the $TiB_2$ films increases with increasing ion energy, and approaches a maximum value of 39 Gpa at ion energy of 85 keV. The tribological property of the TiB2 films is also improved by higher energy of 85keV. The tribological property of the $TiB_2$ films is also improved by higher energy ion beam bombardment. There is no major disparity in the mechanical properties of double-layer $TiB_2$/TiN coatings and TiN/$TiB_2$ coatings. Both show an improved wear resistance compared with single-layer $TiB_2$ films. The adhesion of double-layer coatings is also superior to that of single-layer films.