• 한국재료학회지
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• 제16권8호
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• pp.490-496
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• 2006

ITO monolayer and ITO/Ag/ITO multilayer thin films are prepared by D.C. magnetron sputtering method. Ag layer was inserted for applying ITO to a flexible substrate at low temperature. Carrier concentration and carrier mobility of ITO and ITO/Ag/ITO thin films were measured, the transmittance of them also was done. The amorphous phase was confirmed to be combined in addition to (400) and (440) peaks from XRD result of ITO thin film. As the substrate temperature increased, the preferred orientation of (400) appeared. From the result of application of Ag layer at room temperature, the growth of columnar structure was inhibited, and the amorphous phase formed mostly. The ITO/Ag/ITO thin film represented the transmittance of above 80% when the thickness of Ag layer was 50 ${\AA}$, and the concentration of carrier increased up to above 10 times than that of ITO thin film. Finally, since very low resistance of 3.9${\Omega}/{\square}$ was observed, the effective application of low temperature process is expected to be possible for ITO thin film.

• 한국기계가공학회지
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• 제8권3호
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• pp.62-67
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• 2009

Pt thin films on Cr or Ti interlayer were deposited onto a tungsten carbide(WC) substrate by the ion beam assisted DC magnetron sputtering. The various atomic percent of Cr and Ti underneath of the Pt films were prepared to examine the total thin film characteristics. The microstructure and surface analysis of the specimen were conducted by using the SEM, XRD and AFM. Mechanical properties such as hardness and adhesion strength of Pt thin film also were examined. The interlayer of pure Ti was formed with 40 nm thickness while that of pure Cr was done with 50 nm as standard reference. The growth rate of either Cr or Ti thin film was almost same under the same deposition conditions. The SEM images showed that anisotropic grain of Pt thin films consisting of dense columnar structures irrespectively grew from the different target compositions. The values of hardness and adhesion strength of Cr/Pt thin film coated on a WC substrate were higher than those of Ti/Pt thin film.

• 한국재료학회지
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• 제28권9호
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• pp.516-521
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• 2018

Copper oxide thin films are deposited using an ultrasonic-assisted spray pyrolysis deposition (SPD) system. To investigate the effect of substrate temperature and incorporation of a chelating agent on the growth of copper oxide thin films, the structural and optical properites of the copper oxide thin films are analyzed by X-ray diffraction (XRD), field-emssion scanning electron microscopy (FE-SEM), and UV-Vis spectrophotometry. At a temperature of less than $350^{\circ}C$, three-dimensional structures consisting of cube-shaped $Cu_2O$ are formed, while spherical small particles of the CuO phase are formed at a temperature higher than $400^{\circ}C$ due to a Volmer-Weber growth mode on the silicon substrate. As a chelating agent was added to the source solutions, two-dimensional $Cu_2O$ thin films are preferentially deposited at a temperature less than $300^{\circ}C$, and the CuO thin film is formed even at a temperature less than $350^{\circ}C$. Therefore the structure and crystalline phase of the copper oxide is shown to be controllable.

• 마이크로전자및패키징학회지
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• 제26권2호
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• pp.15-21
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• 2019

원자층 증착법(ALD: atomic layer deposition)으로 $150^{\circ}C$에서 성장된 zinc oxide (ZnO) 초박막의 두께 변화에 따른 구조적, 전기적, 광학적 특성을 조사하였다. ZnO 박막을 증착하기 위해 금속 전구체와 반응물로 각각 diethylzinc와 deionized water를 사용하였다. ALD 사이클 당 성장률은 $150^{\circ}C$에서 약 0.21 nm/cycle로 일정 하였으며, 50 사이클 이하의 샘플들은 초기 ALD 성장 단계에서 상대적으로 얇은 두께로 인하여 비정질 성질을 갖는 것으로 보였다. 100 사이클에서 200 사이클로 두께가 증가함에 따라 ZnO 박막의 결정성이 증가하였고 hexagonal wurtzite 구조를 보였다. 또한, ZnO 박막의 입자 크기가 ALD 사이클의 수의 증가에 따라 증가되었다. 전기적 특성 분석 결과 박막 두께의 증가에 따라서 비저항 값이 감소하였으며, 이는 박막 두께 증가에 따른 입자 크기 증가 및 결정성 개선으로 더 두꺼운 ZnO 박막에서 입자 경계의 농도 감소와 상관 관계가 있음을 알 수 있었다. 광학적 특성 분석 결과 근 자외선 영역 (300 nm~400 nm)에서의 밴드 엣지 흡수가 증가 및 이동되었는데 이 현상은 ZnO 박막 두께의 증가에 따른 캐리어 농도의 증가가 기인 한 것으로, 이 결과는 박막 두께의 증가에 따른 저항률 감소와 잘 일치한다. 결과적으로 박막의 두께가 증가하면 막 면의 응력이 완화되어 밴드 갭이 감소하고 결정성 및 전도성이 향상됨을 알 수 있었다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.42-42
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• 2006

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.58.1-58.1
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• 2007

• 한국컴퓨터정보학회논문지
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• 제29권4호
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• pp.55-62
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• 2024

본 논문에서는 HMI 디스플레이를 활용하고 IoT 기술을 이용한 박막식 수경 재배 방식의 식물재배기를 제안한다. 기존의 식물재배기는 토양 기반의 재배로 관리가 어렵고, 개방된 재배 환경으로 인해 환경조건 최적화가 어려웠다. 또한 즉각적인 제어가 어려워 식물재배의 성장이 지연되어 식물재배에 대한 문제점이 있다. 이러한 문제를 해결하기 위해, MCU와 센서를 연결하여 재배 환경을 구축하고, HMI 디스플레이와 연동하여 환경정보를 확인하고 빠르게 제어할 수 있게 구현하였다. 또한, 환경정보의 변화를 최소화하기 위해 케이스를 적용하였다. 박막식 수경 재배시스템 구현으로 토양에 관한 관리를 편하게 하였고 동작과 제어를 통해 기능성을 높였으며, 디스플레이를 통해 환경정보를 쉽게 파악할 수 있다. 기존 재배기와 수경재배기에서의 작물 재배 실험으로 성장이 빠른 효과성을 확인하였다. 향후 연구 방향으로는 재배 환경정보 전송 및 저장, 비전 카메라를 활용한 성장 정보를 연동하고 비교하여 생육 정보를 최적화할 것이다. 이를 통해 효율적이고 안정적인 식물재배할 수 있을 것으로 기대한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.484-488
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• 1997

BSCCO thin film is fabricated cia both processes of co-deposition and layer-by-layer deposition at an ultralow growth rate using ion beam sputtering method. The adsorption of Bi atom and the appearance of Bi-2212 phase shows large differance between both processes. It is found that the resident time of Bi vapor species on the surface of the substrate strongly dominates the film composition and the formation of the structure.

• 한국재료학회지
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• 제27권8호
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• pp.403-408
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• 2017

We investigated the effect of ZnO buffer layer on the formation of ZnO thin film by ultrasonic assisted spray pyrolysis deposition. ZnO buffer layer was formed by wet solution method, which was repeated several times. Structural and optical properties of the ZnO thin films deposited on the ZnO buffer layers with various cycles and at various temperatures were investigated by field-emission scanning electron microscopy, X-ray diffraction, and photoluminescence spectrum analysis. The structural investigations showed that three-dimensional island shaped ZnO was formed on the bare Si substrate without buffer layers, while two-dimensional ZnO thin film was deposited on the ZnO buffer layers. In addition, structural and optical investigations showed that the crystalline quality of ZnO thin film was improved by introducing the buffer layers. This improvement was attributed to the modulation of the surface energy of the Si surface by the ZnO buffer layer, which finally resulted in a modification of the growth mode from three to two-dimensional.

• E2M - 전기 전자와 첨단 소재
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• 제16권9호
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• pp.63.2-64
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• 2003

Epitaxial yttrium-stabilized HfO$_2$ thin films were deposited on p-type (100) Si substrates by pulsed laser deposition at a relatively lower substrate temperature of 550. Transmission electron microscopy observation revealed a fixed orientation relationship between the epitaxial film and Si; that is, (100)Si.(100)HfO$_2$ and [001]Si/[001]HfO$_2$. The film/Si interface is not atomically flat, suggesting possible interfacial reaction and diffusion, X-ray photoelectron spectrum analysis also revealed the interfacial reaction and diffusion evidenced by Hf silicate and Hf-Si bond formation at the interface. The epitaxial growth of the yttrium stabilized HfO$_2$ thin film on bare Si is via a direct growth mechanism without involoving the reaction between Hf atoms and SiO$_2$ layer. High-frequency capacitance-voltage measurement on an as-grown 40-A yttrium-stabilized HfO$_2$ epitaxial film yielded an dielectric constant of about 14 and equivalent oxide thickness to SiO$_2$ of 12 A. The leakage current density is 7.0${\times}$ 10e-2 A/$\textrm{cm}^2$ at 1V gate bias voltage.