• 한국재료학회지
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• 제14권11호
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• pp.780-785
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• 2004

The degradation mechanism of soft magnetic properties of $Fe-Hf-N/Cr/SiO_2$ thin films reacted with a bonding glass was investigated. When $Fe-Hf-N/Cr/SiO_2$ films were annealed under $600^{\circ}C$ without the bonding glass, the compositions and the soft magnetic properties of Fe-Hf-N layers were not changed. However, after reaction with the bonding glass at $550^{\circ}C$, the soft magnetic properties of the film were degraded. At $600^{\circ}C$, the saturation magnetization of the reacted film decreased to 13.5 kG, and its coercivity increased to 4 Oe, and its effective permeability decreased to 700. It was founded that O diffused from the glass into the Fe-Hf-N layers during the reaction and generated $HfO_2$ phases. It was considered that the soft magnetic properties of the $Fe-Hf-N/Cr/SiO_2$ films reacted with the bonding glass were primarily degraded by the formation of the Fe-Hf-O-N layer of which the Fe content was below 60 $at\%$, and secondarily degraded by the Fe-Hf-O-N layer above 70 $at\%$.

• 마이크로전자및패키징학회지
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• 제16권4호
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• pp.17-22
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• 2009

Two different organic-inorganic hybrid thin film transistors (OITFTs) with the structures of glass/ITO/ZnO/PMMA/Al (staggered structure) and glass/ITO/PMMA/ZnO/Al (inverted staggered structure), were fabricated and their electrical and structural properties were compared. The ZnO thin films used as active channel layers were deposited by the atomic layer deposition (ALD) method at a temperature of $100^{\circ}C$. To investigate the effect of the substrates on their properties, the ZnO films were deposited on bare glass, PMMA/glass and ITO/glass substrates and their crystal properties and surface morphologies were analyzed. The structural properties of the ZnO films varied with the substrate conditions. The ZnO film deposited on the ITO/glass substrate showed better crystallinity and morphologies, such as a higher preferred c-axis orientation, lower FWHM value and larger particle size compared with the one deposited on the PMMA/glass substrate. The field effect mobility ($\mu$), threshold voltage ($V_T$) and $I_{on/off}$ switching ratio for the OITFT with the staggered structure were about $0.61\;cm^2/V{\cdot}s$, 5.5 V and $10^2$, whereas those of the OITFT with the inverted staggered structure were found to be $0.31\;cm^2/V{\cdot}s$, 6.8 V and 10, respectively. The improved electrical properties for the staggered OITFTs may originate from the improved crystal properties and larger particle size of the ZnO active layer.

• 한국진공학회지
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• 제2권4호
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• pp.480-485
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• 1993

Factros considered building the magnetron sputtering system for TFT LCD (thin film transistor liquid crystal display0 metallization were thin film thichnes uniformity, temperature uniformity and the pressure gradient of sputtering gas flow in vacuum chamber, base pressure, and the stability fo the carrier moving . The system was consisted of a deposition chamber, a pre-heating chamber, a RF-precleaning chamber and a load/unload lock chamber. The system was designed to handle a substrate with dimension of 400$\times$400mm. The temperautre uniformity of a heater table developed showed $250 ^{\circ}C\pm$5% accuracyon the substrate glass. A base pressure of 1.8 $\times$10-7 torr was obtained after 24 hours pumping with a cryo pump. After an aluminum target was installed in a sputtering source and the film wa sdeposited on the glass, the uniformity, reflectivity and sheet resistance of the deposited film were measured.

• 한국안전학회지
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• 제13권1호
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• pp.85-91
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• 1998

Sol-gel derived silica films were prepared by dip-coating onto polymethylmethacylate with Tetraethoxysilane(TEOS) as starting materials. Film properties such as viscosity and thickness were investigated as a function of dip speed, waterprecursor ratio, sol aging time. IR spectra of the gel films prepared from TEOS at various R are given. At small values of R the absorption peaks assignable to C-H vibration in $-OC_2H_5$ groups are observed around 3000 and 1500-1300 $cm^{-1}$. These bands indicate that the -$-OC_2H_5$ groups are retained in the gel at small values of R because of incomplete hydrolysis of TEOS. Film behaviour was interpreted in terms of the dependence of hydrolysis and condensation rates on the interplay between sol pH and waterprecursor ratio. Film thickness was found to increase by approximately a factor of two as waterprecursor ratio increased from two to six. Film thickness also increased with sol prepolymerization time. Surface quality was correlated with processing conditions.

• 한국안광학회지
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• 제7권2호
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• pp.163-167
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• 2002

$Ni(OH)_2/Ni$ Glass 박막에서 전기변색 속도 개선에 대한 연구를 수행하였다. 이는 선글라스의 변색속도가 수분 이상 소요되는 단점을 해결하고자 e-beam evaporator를 이용하여 니켈 금속 박막을 증착시킨 후, 전기화학적 산화-환원 반응으로 $Ni(OH)_2$에 대한 전기변색 특성을 연구하였다. 전기전도성을 갖는 ITO 에서보다 Glass 위에서의 $Ni(OH)_2$의 변색 속도가 오히려 빠르다. 이는 전위와 투과율을 측정함으로서 알 수 있다. XPS를 이용하여 Glass와 $Ni(OH)_2$ 사이의 초박막(${\sim}10{\AA}$) Ni 금속의 존재를 확인하였고, 이 나노 박막은 전기변색 장치의 응답 속도에 영향을 마쳤다. 기존의 선글라스가 5분 정도 소요되는 반면 니켈 나노 박막을 이용한 변색소자에서는 1~2초 정도 소요된다. 이론적으로는 수 ms 이내이지만 전기적 저항으로 인해 초 단위의 응답속도를 보이고 있다.

• 한국재료학회지
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• 제4권1호
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• pp.31-36
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• 1994

Mn-Zn ferrite를 가공하여 VCR헤드의 제조과정에서 비자성체 gap용 $SiO_{2}$증착층과 유리와의 접합시 유리내에 기포 형태의 결함이 발생하는 경우가 있다. 기판의 조도나 $SiO_{2}$의 증착속도의 영향을 분석한 결과, 기포의 생성원인이 $SiO_{2}$ 증착층과 접합유리의 융착시 계면에 존재하는 요철의 불완전한 충진에 의한 것으로 나타났다. 따라서 이러한 기포생성을 억제시키는 위해서는 기판을 최대한 경면 연마시켜 표면조도를 작게하고 $SiO_{2}$증착속도를 조절함으로써 $SiO_{2}$증착층의 표면조도를 작게하여 유리 융착시 계변의 요철 크기를 작게해야 한다. 기판을 0.05$\mu\textrm{m}$알루미나 분말로 경면연마시키고, 10% Osub 2/분압을 갖는 Ar plasma상태하로 조절된 증착속도로 즈악된 $SiO_{2}$증착층과 접합유리의 융착시 기포가 전혀 발생치 않았다.

• 한국재료학회지
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• 제9권7호
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• pp.663-669
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• 1999

분산특성이 다른 두 종류의 Ag 분말과 점도가 다른 두 종류의 유리를 사용하여 Ag 후막 도체를 제조하고 이들이 후막의 미세구조에 어떠한 영향을 미치고 그 미세구조가 전기특성에 미치는 영향을 조사하였다. Ag 분말의 분산특성이 좋을수록 그리고 사용된 유리의 점도가 낮을수록 후막의 미세구조는 잘 발달된 치밀한 조직을 보였으며 면저항값도 감소하였다. 이는 Ag 분말의 분산특성이 좋을수록 용융 유리에 의한 Ag 입자들의 미세 재배치의 속도가 빨라지고, 또한 유리의 점도가 낮을수록 모든 미세구조 발전단계에서 그 속도가 증가하기 때문이며. 이러한 미세조직의 치밀화가 후막의 면저항값을 제어하기 때문이다. 소성시간이 증가하여도 더 이상 전기저항값의 저하가 없는 저항감소의 포화시간이 존재함을 확인하였으며, 이 포화시간 역시 후막의 미세구조에 크게 의존함을 알 수 있었다

• 한국응용과학기술학회지
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• 제19권2호
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• pp.131-136
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• 2002

As model waterborne acrylic coatings, mono-dispersed poly(butyl acrylate-methyl methacrylate) copolymer latexes of random copolymer and core/shell type graft copolymer were prepared by seeded multi-staged emulsion polymerization with particle size of $180{\sim}200$ nm using semi-batch type process. Sodium lauryl sulfate and potassium persulfate were used as an emulsifier and an initiator, respectively. The effect of particle texture including core/shell phase ratio, glass transition temperature and crosslinking density, and film forming temperature on the film formation and final properties of film was investigated using SEM, AFM, and UV in this study. The film formation behavior of model latex was traced simultaneously by the weight loss measurement and by the change of tensile properties and UV transmittance during the entire course of film formation. It was found that the increased glass transition temperature and higher crosslinking degree of latex resulted in the delay of the onset of coalescence of particles by interdiffusion during film forming process. This can be explained qualitatively in terms of diffusion rate of polymer chains. However, the change of weight loss during film formation was insensitive to discern each film forming stages-I, II and III.

• 한국표면공학회지
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• 제42권5호
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• pp.203-207
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• 2009

Interaction between human osteoblast (hFOB 1.19) and CrN films was conducted in vitro. CrN films were produced by cathodic arc plasma deposition. The surface was characterized by atomic force microscopy (AFM). CrN films, glass substrates and TiN films were cultured with human osteoblasts for 48 and 72 hours. Actin stress fiber patterns and cell adhesion of osteoblasts were found less organized and weak on CrN films compared to those on the glass substrates and the TiN films. Human osteoblasts also showed less proliferation and less distributed microtubule on CrN films compared to those on glass substrates and TiN films. Focal contact adhesion was not observed in the cells cultured on CrN films, whereas focal contact adhesion was observed well in the cells cultured on glass substrates and TiN films. As a result, the CrN film is a potential candidate as a surface coating to be used for implantable devices which requires minimal cellular adhesion.

• 한국세라믹학회지
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• 제52권4호
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• pp.290-293
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• 2015

The properties of the IZTO thin films on the glass were studied with a variation of the $SiO_2$ buffer layer thickness. $SiO_2$ buffer layers were deposited by plasma-enhanced chemical vapor deposition (PECVD) on the glass, and the In-Zn-Tin-Oxide (IZTO) thin films were deposited on the buffer layer by RF magnetron sputtering. All the IZTO thin films with the $SiO_2$ buffer layer are shown to be amorphous. Optimum $SiO_2$ buffer layer thickness was obtained through analyzing the structural, morphological, electrical, and optical properties of the IZTO thin films. As a result, the IZTO surface roughness is 0.273 nm with a sheet resistance of $25.32{\Omega}/sq$ and the average transmittance is 82.51% in the visible region, at a $SiO_2$ buffer layer thickness of 40 nm. The result indicates that the uniformity of surface and the properties of the IZTO thin film on the glass were improved by employing the $SiO_2$ buffer layer and the IZTO thin film can be applied well to the transparent conductive oxide for display devices.