Sol-Gel derived Ga-In-Zn-O Semiconductor Layers for Solution-Processed Thin-Film Transistors

문주호,김동주,정선호,Jooho Moon,Chiyoung Park,Minhyon Jeon,Won-Chol Sin,Jinha Jung,Hyun-Jung Woo,Seung-Hyun Kim,Jowoong Ha 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.1

We have prepared a solution processed oxide semiconductor layer for thin-film transistors. The oxide semiconductor thin-film were prepared by spin coating a sol-gel precursor solution based on Ga and In-co-doped ZnO (GIZO). The sol-gel-derived GIZO film were uniform and have smooth surface morphology (rms. roughness ~0.7 nm). The device performance of the solution-processed thin-flm transistors was analyzed as a function of the doping concentration and the annealing temperature. The transistors annealed at 450 ℃ showed clear switching behavior and output characteristic with relatively high field effect mobility (~0.1 ㎠/V·s) and low threshold voltage (~5.4 V). Even when annealed at 300 ℃, they showed reasonable field effect mobility (~0.03 cm2/Vs) and a lower threshold voltage (~-0.2 V). Our findings demonstrate the feasibility of using sol-gel-based oxide semiconductor transistors for successful application to cost-effective and mass-producible display and optoelectronic devices with enhanced device performance. We have prepared a solution processed oxide semiconductor layer for thin-film transistors. The oxide semiconductor thin-film were prepared by spin coating a sol-gel precursor solution based on Ga and In-co-doped ZnO (GIZO). The sol-gel-derived GIZO film were uniform and have smooth surface morphology (rms. roughness ~0.7 nm). The device performance of the solution-processed thin-flm transistors was analyzed as a function of the doping concentration and the annealing temperature. The transistors annealed at 450 ℃ showed clear switching behavior and output characteristic with relatively high field effect mobility (~0.1 ㎠/V·s) and low threshold voltage (~5.4 V). Even when annealed at 300 ℃, they showed reasonable field effect mobility (~0.03 cm2/Vs) and a lower threshold voltage (~-0.2 V). Our findings demonstrate the feasibility of using sol-gel-based oxide semiconductor transistors for successful application to cost-effective and mass-producible display and optoelectronic devices with enhanced device performance.

공급과 경험

문주호(Moon, Joo-ho) 대한건축학회 2019 建築 Vol.63 No.8

RAW 264.7 대식세포 내에서 남정목 열매 추출물의 항염증 효과

문주호 ( Ju-ho Moon ),고흥 ( Heung Go ),신선미 ( Seon-mi Shin ),김기태 ( Ki-tae Kim ) 대한한의진단학회 2013 大韓韓醫診斷學會誌 Vol.17 No.3

Objectives This study was designed to investigate the anti-inflammatory effect of extracts from Ligustrum obtusifolium S. fruits(LOF) in RAW 264.7 Macrophages stimulated with lipopolysaccharide(LPS). Methods We examined productions of nitric oxide(NO), reactive oxygen species(ROS), inducible isoforms of NO synthase(iNOS), cyclooxygenase-2(COX-2) to investigate the anti-inflammatory effect of LOF extracts. In addition, we measured generation of pro-inflammatory cytokines(TNF-α, IL-6). Results Cell viability showed that LOF extracts had no cytotoxicity in Raw 264.7 cells. The treatment with LOF extracts significantly decreased the generation of NO and pro-inflammatory cytokines(TNF-α, IL-6) in LPS-stimulated macrophage cells. Furthermore LOF extracts inhibited intracellular ROS generation dose dependently and reduced the expression of iNOS, COX-2 proteins. Conclusions These results showed that the LOF extracts had an anti-inflammatory effect on LPS-stimulated Raw 264.7 cells. These findings provide scientific support for the use of this Ligustrum obtusifolium S. for inflammatory-related diseases.

용적률 게임, 젊은 건축가의 생존

문주호(Moon, Ju-Ho) 대한건축학회 2016 建築 Vol.60 No.12

고효율 소형 연료전지의 개발 : I.유기-무기 나노복합 전해질막의 합성

박용일,문주호,김혜경,김석환,Park, Yong-Il,Moon, Joo-Ho,Kim, Hye-Kyung,Kim, Suk-Hwam 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.1

New fast proton-conducting organic-inorganic nanocomposite membranes were successfully fabricated using polymer matrix obtained through proper oxidation of thiol ligands in (3-Mercaptopropyl) trimethoxysilane (MPTS) and hydrolysis/condensation reaction of (3-glycidoxypropyl) trimethoxysilane (GPTS). The obtained nanocomposite membranes showed relatively hirh proton-conductivity over $10^{-2}S/cm$ at $ 25^{circ}C$. The proton conductivities of the fabricated composite membranes increased up to $3.6{\times}10^{-1}$ S/cm cm by increasing temperature and relative humidity to $70^{circ}C$ and 100 $100RH\%$. The high proton conductivity of the composites Is due to the proton conducting path through the GPTS-derived 'pseudo-polyethylene oxide 'network in which sulfonic acid ligands work as a proton donor. (3-Mercaptopropyl) trimethoxysilane(MPTS)의 thoil기(-SH)의 적절한 산화 및 (3-glycidoxypropyl) trimethooxysilane(GHS)와의 수화/중축합 반응을 통하여 얻어진 고분자 기질을 사용하여 새로운 고 프로톤 전도성 유기-무기 나노복합막을 성공적으로 합성하였다. 합성된 나노복합막으로부터 얻어진 프로톤 전도도는 $25^{circ}C$에서 $10^{-2} S/cm$ 이상의 높은 값을 나타내었으며, 온도와 상대습도를 $70^{circ}C$와 $100RH\%$로 증가시킴에 따라 전도도는 $3.6{\times}10^{-1}$ S/cm까지 증가하였다. 복합체의 높은 프로톤 전도도는 MPTS 말단의 thiol의 산화에 의해 얻어지는 아황산기$(-SO_{3}^{-})$가 프로톤 donor로서 작용하고, GHS로부터 유도된 'pseudo polyethylene oxide' 네트워크가 프로톤의 전도 path로 작용하고 있음을 나타낸다.

LSGM계 고체산화물 연료전지의 전기화학적 성능에 미치는 계면반응층의 영향

김광년,문주호,김형철,손지원,김주선,이해원,이종호,김병국,Kim, Kwang-Nyeon,Moon, Jooho,Kim, Hyoungchul,Son, Ji-Won,Kim, Joosun,Lee, Hae-Weon,Lee, Jong-Ho,Kim, Byung-Kook 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.10

LSGM is known to show very serious interfacial reaction with other unit cell components, such as electrode, electrode functional or buffering layers. Especially, the formation of very resistive LaSr$Ga_{3}$$O_{7}$ phase at the interface of an anode and an electrolyte is the most problematic one in LSGM-based SOFCs. In this study, we investigated the interfacial reactions in LSGM-based SOFCs under different unit cell configurations. According to the microstructural analysis on the interfacial layer between an electrolyte and its neighboring component, serious interfacial reaction zone was observed. From the electrical and electrochemical characterization of the cell, we found such an interfacial reaction zone not only increased the internal ohmic resistance but also decreased the OCV(Open Cell Voltage) of the unit cell, and thus consequently deteriorated the unit cell performance.

로보 디스펜싱을 이용하여 직접묘화방식으로 제조된 고출력 소형 고체산화물 연료전지

김용범,문주호,김주선,이종호,이해원,Kim, Yong-Bum,Moon, Jooho,Kim, Joosun,Lee, Jong-Ho,Lee, Hae-Weon 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.6

Line Shaped Solid Oxide Fuel Cell (SOFC) with multilayered structure has been fabricated via direct-writing process. The cell is electrolyte of Ni-YSZ cermet anode, YSZ electrolyte and LSM cathode. They were processed into pastes for the direct writing process. Syringe filled with each electrode and electrolyte paste was loaded into the computer-controlled robe-dispensing machine and the paste was dispensed through cylindrical nozzle of 0.21 mm in diameter under the air pressure of 0.1 tow onto a moving plate with 1.22 mm/s. First of all, the anode paste was dispensed on the PSZ porous substrate, and then the electrolyte paste was dispensed. The anode/electrolyte and the PSZ substrate were co-fired at $1350^{\circ}C$ in air atmosphere for 3 h. The cathode layer was similarly dispensed and sintered at $1200^{\circ}C$ for 1 h. All the electrode/electrolyte lines were visually aligned during the direct writing process. The effective reaction area of fabricated SOFC was $0.03 cm^2$, and the thickness of anode, electrolyte and cathode was 20 $\mu$m, 15 $\mu$m, and 10 $\mu$m, respectively. The single line-shaped SOFC fabricated by direct-writing process exhibited OCV of 0.95 V and maximum power density of $0.35W/cm^2$ at $810^{\circ}C$.

LSGM계 고체산화물 연료전지의 계면안정성을 위한 완층층의 도입

김광년,문주호,손지원,김주선,이해원,이종호,김병국,Kim, Kwang-Nyeon,Moon, Jooho,Son, Ji-Won,Kim, Joosun,Lee, Hae-Weon,Lee, Jong-Ho,Kim, Byung-Kook 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.9

In order to find a proper buffering material which can prohibit an unwanted interfacial reaction between anode and electrolyte of LSGM-based SOFC, we examined a gadolinium doped ceria and scandium doped zirconia as a candidate. For this examination, we investigated the microstructural and phase stability of the interface under different buffering layer conditions. According to the investigation, ceria based material induced a serious La diffusion out of the LSGM electrolyte resulted in the formation of very resistive $LaSrGa_3O_7$ phase at the interface. On the other hand zirconia based material was directly reacted with LSGM electrolyte and thus produced very resistive reaction products such as $La_2Zr_2O_7,\;Sr_2ZrO_4,\;LaSrGaO_4\;and\;LaSrGa_3O_7$. From this study we found that an improper buffering material induced the higher internal cell resistance rather than an interfacial stability.

LSGM계 고체산화물 연료전지의 전해질-음극 사이의 계면안정성

김광년,문주호,손지원,김주선,이해원,이종호,김병국,Kim, Kwang-Nyeon,Moon, Jooho,Son, Ji-Won,Kim, Joosun,Lee, Hae-Weon,Lee, Jong-Ho,Kim, Byung-Kook 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.7

Interfacial reactions at LSGM electrolyte and NiO-GDC anode interfaces were thoroughly investigated with Environmental Scanning Electron Microscopy (ESEM-PHlLIPS XL-30) and Energy Dispersive X-ray (EDX-Link XL30). According to the analysis, serious reaction zone was observed at LSGM/NiO-GDC interface. It was found that the reaction layer was originated from the chemical reaction between NiO and LSGM. The reaction products were identified as La deficient form of LSGM based perovskite and Ni-La-O compounds such as LaSrGa$_{3}$O$_{7}$ and LaNiO$_{3}$ from the X-Ray Diffraction (XRD, Philips) analysis. According to the electrical characterization, interfacial layer was very electrically resistive which would be the cause of high internal resistance and low power generating characteristic of the unit cell.

PVP 결합제를 이용한 지르코니아/알루미나 복합분말의 분무건조

심형보,문주호,김대준,Shim, Hyung-Bo,Moon, Joo-Ho,Kim, Dae-Joon 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.5

지르코니아/알루미나 복합분말의 분무건조로 제조된 과립들의 형상과 성형시 과립 경계면 파괴에 분말의 분산 정도, 결합제의 종류, 그리고 고형분말 함량이 미치는 영향을 관찰하였다. 구형의 과립은 복합분말 슬러리가 완전 분산이 되지 않고 약간의 floc을 형성하고 결합제로서 Polyvinyl Pyrrolidone(PVP)을 사용했을 때 얻어졌다. PVP를 결합제로 사용하고 분말함량이 32.5 vol%인 슬러리로 분무건조한 분말은 성형시 과립경계면이 파괴되어 소결밀도는 99.7%이었고 굴곡강도는 850Mpa이었다. Zirconia/alumina mixture powder was spray-dried various degree of dispersion, type of dispersants and powder content in the slurry. The quality of the granule was determined by observation of the granule shapes after spray drying and fracture of intergranular boundaries during pressing. Defect-free granules were obtained from the powders that formed weak flocs in the slurry. The granules, spray-dried from the slurry containing 32.5 vol% powder mixture and PVP as binder, were fractured completely during shaping and the sintered specimens showed a density of 99.7% and a flexural strength of 850 MPa.