• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.357.2-357.2
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• 2014

Ruthenium (Ru) 박막은 우수한 화학적 열적 안정성 및 높은 일함수(4.7eV) 특성으로 인해 20 nm급 이하의 차세대 DRAM capacitor의 전극 물질 및 Cu metalization을 위한 seed layer로 각광을 받고 있다. Ru박막의 나노스케일 정보전자소자로의 적용을 위해서는 두께제어가 용이하고 3D 구조에서 우수한 단차 피복 특성을 갖는 atomic layer deposition (ALD)을 이용한 박막 형성이 필수적이다. 이에 본 연구에서는 ALD 방법을 이용하여 0가의(cymene) (1,5-hexadiene) Ru (0) (C16H24Ru) 전구체를 합성, ALD 방법을 이용하여 우수한 초기성장거동을 갖는 Ru 박막을 증착 하였다. 형성된 Ru 박막의 표면 형상, 두께, 밀도를 주사전자현미경(Scanning electron microscopy)과 X-선 반사율 측정(X-ray reflectometer)으로 조사하였다. 또한 전기적 특성을 4침법(four-point-probe)으로 측정하였고, 박막의 화학적 조성과 결정성의 정보를 X-선 광전자분광법(X-ray photoelectron spectroscopy)과 X-선 회절(X-ray diffraction)을 이용하여 확인하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.182-183
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• 2009

플라즈마 원자층 증착법을 이용하여 Ru-TiN 빅막을 합성하였다. 박막 내 Ru의 함량은 Ru의 unit-cycle의 수에 따라 선형적으로 증가하였으며, Ru 함량이 증가함에 따라 박막의 비저항을 $3700{\mu}{\Omega}{\cdot}cm$에서 $190{\mu}{\Omega}{\cdot}cm$까지 자유롭게 조절할 수 있었다. Ru의 함량이 0.40 이상인 경우, Ru과 TiN 두물질이 교차 증착되어 서로의 결정 성장을 충분히 억제함으로서, 비정질구조를 가짐을 확인할 수 있었다. 또한, $O_2$ 분위기에서 열처리를 진행한 결과, Ru의 조성비가 0.40이상인 경우 $700^{\circ}C$까지 면저항의 변화가 거의 없음을 확인할 수 있었다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.4
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• pp.281-288
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• 2001

PZT thin films (3500$\AA$) have been prepard on the Ru/Ru $O_2$ and Ru $O_2$ bottom electrodes with a RF magnetron sputtering system using P $b_{1.05}$(Z $r_{0.52}$, $Ti_{0.48}$) $O_3$ ceramic target. Ru/Ru $O_2$ bottom electrode was fabricated by in-situ processing controlled the $O_2$ partial pressure. The PZT thin films deposited on the Ru/Ru $O_2$ bottom electrode were preferred oriented (101) plane. The PZT thin films deposited on the Ru/Ru $O_2$ bottom electrodes showed better electrical properties than those with Ru $O_2$ bottom electrodes because Ru $O_2$ prevented oxygen vacancies and impurities from existing withing the interface and substrate.e.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.149-149
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• 2008

Metal-Insulator-Metal(MIM) capacitors have been studied extensively for next generation of high-density dynamic random access memory (DRAM) devices. Of several candidates for metal electrodes, Ru or its conducting oxide $RuO_2$ is the most promising material due to process maturity, feasibility, and reliability. ALD can be used to form the Ru and RuO2 electrode because of its inherent ability to achieve high level of conformality and step coverage. Moreover, it enables precise control of film thickness at atomic dimensions as a result of self-limited surface reactions. Recently, ALD processes for Ru and $RuO_2$, including plasma-enhanced ALD, have been studied for various semiconductor applications, such as gate metal electrodes, Cu interconnections, and capacitor electrodes. We investigated Ru/$RuO_2$ thin films by thermal ALD with various deposition parameters such as deposition temperature, oxygen flow rate, and source pulse time. Ru and $RuO_2$ thin films were grown by ALD(Lucida D150, NCD Co.) using RuDi as precursor and O2 gas as a reactant at $200\sim350^{\circ}C$.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.159-159
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• 2009

In this work, nitrogen and oxygen functionalities was introduced to the graphite nanofibers (GNFs) and their effect on electrocatalytic performance of the GNF supports for direct methanol fuel cells (DMFCs) was invesigated. The nitrogen and oxygen groups were introduced through the urea treatments and acid treatment, respectively. And, PtRu catalysts deposited on modified GNFs were prepared by a chemical reduction method. The catalysts were characterized by means of elemental analysis, nitrogen adsorption, and X-ray photoelectron spetroscopy (XPS). The structure and morphological characteristics of the catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). As a result, the Pt-Ru nanoparticles were impregnated on GNFs with good formation in 3-5 nm. And, the cyclic voltammograms for methanol oxidation revealed that the methanol oxidation peak varied depending on changes of surface functional groups. It was thus considered that the PtRu deposition was related to the reduction of PtRu and surface characteristics of the carbon supports. The changes of surface functional groups were related to PtRu reduction, significantly affect the methanol oxidation activity of anode electrocatalysts in DMFCs.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.3
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• pp.85-94
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• 2012

Objectives: We have studied the syndrome differentiation of ultrasound of retroverted uterus(RU) as the inspection in traditional Korean medicine. Methods: Eighty-four patients, who visited H clinic for infertility treatment, were recruited and evaluated by questionnaires and ultrasound, from April, 2012 to May, 2012. We used ultrasound(Logiq C3; GE Health care) for examination of RU. For statistics, we used Fisher's extract test to evaluate the RU and symptoms, and Chi-square test to evaluated the RU and syndrome differentiations, and Student T-test for the relationship between RU and each score of syndrome differentiation, using PASW Statistics(version 18.0.0) and GraphPad Prism(version 5.01). Results: 1. RU was correlated with moderate or severe dysmenorrhea and premenstrual lower abdominal pain. 2. In syndrome differentiation, blood stasis questionnaire was correlated with RU. 3. RU was related with dysmenorrhea, mass of low abdomen, pressure pain, clod of menstrual blood, dyspareunia. Conclusions: The ultrasound of RU might be related with the syndrome of blood stasis.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.719-724
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• 1998

A preliminary fuel channel analysis for 35% reactor inlet header (RIH) break in CANDU reactor loaded with the CANFLEX-RU fuel bundles has been performed. The predicted results are compared with those for the reactor compared with those for the reactor loaded with standard 37-element bundles. The maximum fuel centerline and sheath temperatures for the CANFLEX-RU bundle channel were lower by 338 and 122 $^{\circ}C$, respectively, than those for the standard bundle because of the Bower maximum linear power of the CANFLEX-RU bundle In spite of the 0.4 FPS higher power pulse of the CANFLEX-RU bundle case. Fuel integrity margin to fuel breakup for the CANFLEX-RU bundle is about 50 J/g higher than that for the standard bundle. The PT/CT contact for the CANFLEX-RU bundle occurred 2 s later than that for the standard bundle. The PT/CT contact temperature for the CANFLEX-RU bundle was 2 $^{\circ}C$ lower than that for the standard bundle. These provide the CANFLEX-RU bundle with the negligibly enhanced safety margin for the fuel channel integrity in CANDU 6 reactor, compared with the standard bundle.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.9
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• pp.423-429
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• 2002

RuOx thin films were fabricated by the method of liquid delivery MOCVD using Ru(C$_{8}$ $H_{13}$ $O_2$)$_3$ as the precursor and their thermal effects and conductivity were investigated. Ru films deposited at 25$0^{\circ}C$ were annealed at $650^{\circ}C$ for 1min with Ar, $N_2$ or N $H_3$ ambient. The changes of the micro-structure, the surface morphology and the electrical resistivity of the Ru films after annealing were studied. Ar gas was more effective than $N_2$ and N $H_3$ gases as an ambient gas for the post annealing of the Ru films, because of smaller resistivity and denser grains. The X-ray diffraction and X-ray photoelectron spectroscopy results indicate that the Ru $O_2$ phase and the silicidation are not observed regardless of the ambient gases. The minimum resistivity of the Ru film is found to have the value of 26.35 $\mu$Ω-cm in Ar ambient. Voids were formed at Ru/TiN interface of the Ru layer after annea1ing in $N_2$ ambient. The $N_2$ gas generated due to the oxidation of the TiN layer accumulated at the Ru/TiN interface, forming bubbles; consequently, the stacked film may peel off the Ru/TiN interface.e.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.5
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• pp.105-111
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• 2007

In this study, we investigated the conversion performance of de-NOx catalyst for lean-burn natural gas engine. As a de-NOx catalyst, NOx storage reduction catalyst was composed of Pt, Pd and Rh with washcoat including Ba and Ni, Ru-ZSM-5. Ni, Ru-ZSM-5, which was regarded as a NOx direct decomposition catalyst, was made up of ion exchanged ZSM-5 by 5wt.% Ni or Ru. The performance of de-NOx catalyst was evaluated by NOx storage capacity and catalytic reduction in air/fuel, $\lambda=1.6$. The catalytic reaction was also observed when the added fuel was supplied to fuel rich atmosphere by fuel spike period of 5 seconds. The NOx conversion of the catalysts with Ni-ZSM-5 or Ru-ZSM-5 was mainly caused by the effect of NOx adsorption of Ba rather than the catalytic reduction of Ni, Ru-ZSM-5. Ni, Ru-ZSM-5 catalysts can not use for the NSR catalyst because they have quick process in thermal deactivation.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.266-266
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• 2010

Ion beam sputtering(IBS)을 이용한 pattern 형성은 대상 물질의 제한이 적고 물리적 변수의 조절에 의해 쉽게 nano 구조의 형태와 크기를 조절할 수 있다는 점에서 관심을 받아오고 있다. 하지만 IBS를 이용한 pattern 형성이 어려운 물질들도 있어 다양한 기판에서의 nano pattern 형성에 관련된 많은 연구가 보고되고 있다. 본 연구발표에서는 유용한 반도체인 Si 표면에서의 IBS를 이용한 nano 구조 형성이 가능함과 그 과정에 대해 말하고자 한다. Ru을 100nm 두께로 증착시킨 Si(100)을 sputter 했을 때, Ru 표면에 잘 order된 nano pattern이 형성되었다. Sputter 시간이 증가하면서 pattern은 유지된 채 Ru이 깎여 나가다가 pattern의 가장 낮은 부분부터 Si기판이 드러나게 된다. 이 때 노출된 Si은 sputtering에 의해 깎여나가고 아직 Ru이 덮여있는 부분의 Si은 그대로 유지되어, Ru이 모두 sputter 되면서 보여지는 Si의 pattern은 Ru의 그것과 동일한 형태를 띄게 된다. 그 결과, Ru의 pattern이 Si으로 transfer되었음을 AFM과 SAM을 통해 확인할 수 있었다. 또한 IBS를 이용해 pattern 형성이 힘든 metallic glass에도 같은 방식으로 Ru을 쌓아 sputter 해봄으로써 pattern transfer를 확인해 볼 계획이다. 이러한 pattern transfer는 sputtering을 통한 pattern 형성이 어려웠던 다른 물질들에 그 가능성이 있음을 보여주고 있어 sputtering의 응용 폭이 넓어질 것을 기대한다.