실리콘 웨이퍼 공정용 알루미나 정전척의 제작과 특성에 관한 연구

천희곤,조동율,이영섭,박용균,최성호,정광진,Serguei Spoutai 울산대학교 기계부품 및 소재 특성평가연구센터 1999 연구보고서 Vol.1999 No.-

정전척의 유전체 물질로 열전도도와 유전특성 그리고 기계적 특성이 우수한 알루미나에 TiO₂첨가하여 유전체의 비저항을 변화시켜서 정전척(electrostatic chuck)에서 발생하는 정전력인 쿨롱힘(coulomb force)과 존슨-라벡힘(Johnsen-Fahbeck firce_의 영향을 규명하려 하였다. 그리고 비저항, 인가전압, 온도, 습도가 정전력에 어떠한 영향을 주는지 고찰하였으며, 인가전압에 따른 응답 특성에 관하여 고찰하였다. Alumina electrostatic chucks for silicon wafer process with wide range of electrical resistivity were fabricated by controlling the amount of TiO₂ addition (0 wt%, 1.3 wt%, 2 wt%, 2.8 wt%). The dependence of electrostatic force on applied voltage, temperature and humidity was investigated. In addition, response characteristics on applied voltage and relationship between electrical resistivity and electrostatic force characteristics such as Coulomb force and Johnsen-Rahbeck force were discussed

정전분무를 이용한 MOCVD에 의해 증착된 TiO_2 박막의 특성 연구

이영섭,박용균,이성재,조동율,천희곤 울산대학교 2002 공학연구논문집 Vol.33 No.1

정전분무(electrostatic spray)를 이용한 MOCVD방법은 원료를 함유하는 용액을 이용함으로써 이송관의 가열이 필요 없이 장치를 간단하게 할 수 있고, 용액의 유량과 전기장의 세기에 따라 초미세 입자제어도 가능하며, 출발 용액으로부터 박막의 조성을 조절할 수 있는 등의 여러 가지 특징을 가지고 있다. 온도가 증가함에 따라 입자성장과 반응가스에 의한 표면의 밀도가 감소하여 표면조도가 증가하였다. 증착 시간이 증가함에 따라 막의 두께는 증가하지만, 증착시간이 지날수록 +전하를 띤 액적들은 이미 생성된 막의 영향으로 -가 인가된 기판으로의 전하이동을 방해받으므로 island성장과 모세관현상의 표면형상은 거칠고, porous해졌다. 인가전압이 증가할수록 분무시 액적의 사이즈가 작아지므로 막의 표면은 치밀해졌으며, 표면에는 완전분무하지 못한 모액적에 의해 생긴 입자의 수도 적은 경향을 보였다. 산소 분말이 증가할수록 Ti와 O의 세기는 증가하나, C의 세기는 감소하는 경향을 보였다. The electrostatic spray assisted MOCVD has the advantages of simple apparatus without the gas lines, easy control of nano-sized droplets by applied voltage and solution rates and easy control of compositions of thin films by controlling the composition of starting solution. At lower deposition temperatures the morphology of the layers are less porous and rough. With increasing deposition time and thus increasing layer thickness the morphologies of the layers are shift to porous top layer with dense bottom layer and then porous top layer with big sized grain of bottom layer as the result of low growth rates. XPS can be seen that Ti and O intensity increases but C intensity decreses with increasing O_2 flow rates.

UV/Cl₂(g)에 의한 Si-wafer 표면금속 오염물의 건식세정에 관한 연구

손동수,정광진,최성호,천희곤,조동율 울산대학교 1998 공학연구논문집 Vol.29 No.2

본 연구에서는 실리콘 웨이퍼 표면에 존재하는 미량의 Zn, Fe, Ti 금속 오염물들이 UV-excited chlorine radical을 이용한 건식세정 방법으로 제거되는 반응과정을 연구 하였다. 실리콘 웨이퍼 상에 진공증착법으로 원형패턴이 있는 Zn, Fe, Ti 박막을 증착시켜 상온 및 200℃에서 UV/CI₂세정하였을 때, 염소 래디컬(CI*)이 Fe, Zn, Ti와 반응하여 제거되는 것을 반응 전후 광학현미경과 SEM을 통해 표면 형상 변화를 관찰하였고, in-line으로 연결된 XPS를 통해서 반응 후 웨이퍼 표면에 남아있는 화합물의 화학적 결합상태를 관찰하였으며, UV/CI₂세정 후 실리콘 기판이 손상받는 정도를 알기 위해 AFM으로 표면 거칠기를 측정하였다. 광학현미경과 SEM의 분석에 의하면 Zn와 Fe는 쉽게 제거되는 반면 염화물을 형성하기 보다는 휘발성이 적은 산화물을 형성하는 경향이 강한 Ti은 약간만 제거되는 것을 확인하였다. XPS 분석을 통해서 이들 금속 오염물들이 chlorine radical과 반응하여 웨이퍼 표면에 금속 염화물을 형성하고 있는 것을 확인하였고, UV/CI₂세정처리를 하였을 때 실리콘 웨이퍼의 표면 거칠기가 약간 증가하는 것을 알 수 있었다. 지금까지의 결과를 통해 볼 때, 습식세정과 UV/CI₂건식세정을 병행하면 플라즈마 및 레이저를 사용하는 다른 건식세정 방법에 비하여 보다 저온에서 실리콘 기판의 큰 손상 없이 비교적 용이하게 금속 오염물을 제거할 수 있음을 알수 있었다. The reaction mechanisms of dry cleaning of Zn, Fe and Ti trace contaminants on the Si wafer using UV/CI₂ have been studied by SEM, AFM and XPS analyses. The patterned Zn, Fe and Ti films were deposited on the Si wafer surface by thermal evaporation and changes in the surface morphology after dry cleaning using CI₂and UV/CI₂at 200℃ were studied by optical microscopy and SEM. In addition changes in surface roughness of Si wafer by the cleaning was observed by AFM. The chemical bonding states of the Zn, Fe and Ti deposited silicon surface were observed with in-line XPS analysis. Zn and Fe were easily cleaned in the form of volatile zinc-chloride and iron-chloride as verified by the surface morphology changes. Ti which forms involatile oxides was not easily removed at room temperature but was slightly removed by UV/CI₂at elevated temperature of 200℃. It was also found that the surface roughness of the Si wafer increased after CI₂and UV/CI₂cleaning. Therefore, the metallic contaminants on the Si wafer can be easily removed at lower temperature by continuous processes of wet cleaning followed by UV/CI₂dry cleaning.

Thermal MOCVD와 DC pulsed PA-MOCVD에 의해 증착된 TiN 박막 연구

박용균,이영섭,이태수,이성재,조동율,천희곤 울산대학교 2001 공학연구논문집 Vol.32 No.1

유기화합물(TDEAT;Ti[N(C2H5)2]4)과 NH3를 이용하여 thermal MOCVD와 dc pulsed plasma assisted MOCVD(PA-MOCVD)인 2종류의 TiN박막을 증착하여 비교하였다. TiN박막의 특성분석은 XRD, AES, FE-SEM, α-step과 XPS로 연구하였다. DC pulsed plasma assisted MOCVD로 증착된 Tin박막은 ion bombardment 효과에 의해 열적으로 증착된 것보다 더 fine한 columnar구조를 나타내므로써 막의 결정질이 향상되었다. 플라즈마에서의 아르곤 이온의 충돌로 인해 탄소(C)는 오히려 유기 화합물보다 탄소 라디칼로 존재하였다. 따라서 탄소 라디갈은 기판의 강한 (-) potential에 의해 TiN박막에 trap되기 때문에 탄소(C)는 열적으로 증착된 TiN박막보다 더 많은 양이 존재하는 것으로 추정된다. By using of (TDEAT;Ti[N(C2H5)2]4)and ammonia gas source, we deposited two different TiN thin films with thermal MOCVD and dc pulsed plasma assisted MOCVD (PA-MOCVB). The properties of TiN thin films were studied by XRD, AES, FE - SEM, α - step and XPS analyses in this work. The TiN films deposited by dc pulsed PA - MOCVD have a little higher density and a fine columnar structure, compared with thermally deposited TiN thin films. This may be due to ion bombardment effect resulting in improved crystallinity in films. Carbon in the film may exist in the form of carbonic radical rather than organic compound because of collision with Ar ion in the plasma. Consequently, the content of carbon in the film of dc pulsed PA - MOCVD was higher than that in thermally deposited TiN films, because carbon radicals could be trapped in the film by strong negative potential of the substrate.

Mitochondrial citrate accumulation drives alveolar epithelial cell necroptosis in lipopolysaccharide-induced acute lung injury

Yang Hui-Hui,Jiang Hui-Ling,Tao Jia-Hao,Zhang Chen-Yu,Xiong Jian-Bing,Yang Jin-Tong,Liu Yu-Biao,Zhong Wen-Jing,Guan Xin-Xin,Duan Jia-Xi,Zhang Yan-Feng,Liu Shao-Kun,Jiang Jian-Xin,Zhou Yong,Guan Cha-Xi 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Necroptosis is the major cause of death in alveolar epithelial cells (AECs) during acute lung injury (ALI). Here, we report a previously unrecognized mechanism for necroptosis. We found an accumulation of mitochondrial citrate (citratemt) in lipopolysaccharide (LPS)-treated AECs because of the downregulation of Idh3α and citrate carrier (CIC, also known as Slc25a1). shRNA- or inhibitor–mediated inhibition of Idh3α and Slc25a1 induced citratemt accumulation and necroptosis in vitro. Mice with AEC-specific Idh3α and Slc25a1 deficiency exhibited exacerbated lung injury and AEC necroptosis. Interestingly, the overexpression of Idh3α and Slc25a1 decreased citratemt levels and rescued AECs from necroptosis. Mechanistically, citratemt accumulation induced mitochondrial fission and excessive mitophagy in AECs. Furthermore, citratemt directly interacted with FUN14 domain-containing protein 1 (FUNDC1) and promoted the interaction of FUNDC1 with dynamin-related protein 1 (DRP1), leading to excessive mitophagy-mediated necroptosis and thereby initiating and promoting ALI. Importantly, necroptosis induced by citratemt accumulation was inhibited in FUNDC1-knockout AECs. We show that citratemt accumulation is a novel target for protection against ALI involving necroptosis.

Fabrication of tubular porous titanium membrane electrode and application in electrochemical membrane reactor for treatment of wastewater

Hui Tong,Chao Yang,Yanqi Lv,Ling Wang,Koucheng Chen,Xingfu Zhou 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.96 No.-

In this study, tubular titanium membrane (TTM) /SnO2-Sb/SnO2-Sb-CeO2 porous anode was fabricatedand used in continuous tubular membrane reactor for electrochemical treatment of dye wastewater. Xraydiffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electronmicroscopy (HRTEM) were used to evaluate the morphology and microstructure of the different tubulartitanium membrane. Linear sweep voltammetry (LSV) and accelerated service life test are employed toillustrate the performance of TTM/SnO2-Sb/SnO2-Sb-CeO2 porous membrane electrode. It is found thatTTM/SnO2-Sb/SnO2-Sb-CeO2 active layer on titanium membrane has compact microstructure, high over-potential for oxygen evolution (2.10 V vs saturated calomel electrode). The effects of pore diameter,applied voltage andflow rate on the electro-catalytic property of the tubular porous electrode wereinvestigated. Study shows titanium membrane reactor with an optimized pore diameter of 10 mm has thelowest energy consumption which is important for the practical application of electrochemicaltechnology. The performance of titanium tubular membrane reactor is investigated by treatingmethylene blue (MB) wastewater under the cell voltage of 3.0–4.5 V and theflow rate of 2.5–3.5 L min 1. This continuous titanium membrane electrochemical reactor using solar cell show excellent performancein treating dye wastewater and the further potential application in electrochemical synthesis.

Enhanced Biofuel Production from High-Concentration Bioethanol Wastewater by a Newly Isolated Heterotrophic Microalga, Chlorella vulgaris LAM-Q

( Tong Hui Xie ),( Jing Liu ),( Kai Feng Du ),( Bin Liang ),( Yong Kui Zhang ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.10

Microalgal biofuel production from wastewater has economic and environmental advantages. This article investigates the lipid production from high chemical oxygen demand (COD) bioethanol wastewater without dilution or additional nutrients, using a newly isolated heterotrophic microalga, Chlorella vulgaris LAM-Q. To enhance lipid accumulation, the combined effects of important operational parameters were studied via response surface methodology. The optimal conditions were found to be temperature of 22.8oC, initial pH of 6.7, and inoculum density of 1.2 × 108 cells/ml. Under these conditions, the lipid productivity reached 195.96 mg/l/d, which was markedly higher than previously reported values in similar systems. According to the fatty acid composition, the obtained lipids were suitable feedstock for biodiesel production. Meanwhile, 61.40% of COD, 51.24% of total nitrogen, and 58.76% of total phosphorus were removed from the bioethanol wastewater during microalgal growth. In addition, 19.17% of the energy contained in the wastewater was transferred to the microalgal biomass in the fermentation process. These findings suggest that C. vulgaris LAMQ can efficiently produce lipids from high-concentration bioethanol wastewater, and simultaneously performs wastewater treatment.

Arms and Politics on the Korean Peninsula Yong Soon Yim/Eun Ho Lee (Cheongju, Korea : Cheongju University Press, 1983, 369 Pages)

Tong Hui Lee 한국학술연구원 1983 Korea Observer Vol.14 No.2

Section 4. 당뇨병 교육을 위한 정보광장 : 소집단 교육 프로그램 소개 - 임파워먼트 프로그램 중심으로

김동희 ( Tong Hui Kim ) 대한당뇨병학회 2010 임상당뇨병 Vol.11 No.1

`Empowerment` is, `What gives you the ability to do,` have the authority to grant, and has a dictionary meaning. The process of power acquisition, the ability to get what he wants, so it is a common definition. Social and organizational environment for the client`s wish to increase control over the course of clinical practice, intervention, technical means. If this circle was a free public lecture during continuous progress, a free public lecture to complement the shortcomings of the subgroup is to continue the program. Collective nature of the interaction between members of the group through a good role model can be derived through social learning. To establish homogeneity of each group in the dynamics of a group you could see all the benefits that can be won in a subgroup of this program is to proceed. Consider the initial recruitment of a small group certificate, you can participate in daytime programs for women 50~60 age was the main target group would consist of, 50~60 age diabetes, a diabetic female patient and her husband as guardian 50~60 age Units to participate in a group of women has been recruiting. The circle of empowerment perspective applied to the applied part of the program are as follows. 1. To build trust between educators and participants. 2. Educators centered around consumer, not to proceed to proceed. 3. Open questions and create an atmosphere for free. 4. Planner, and individual lifestyle changes for each individual target, a post created to allow management to proceed. (Korean Clinical Diabetes J 11:59-63, 2010)

당뇨병 노인의 여가와 자원봉사활동

김동희 ( Tong Hui Kim ) 대한당뇨병학회 2009 임상당뇨병 Vol.10 No.3