• International Journal of Control, Automation, and Systems
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• 제3권3호
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• pp.477-485
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• 2005

This paper is concerned with the development of a micro tensile testing machine for optically functional materials such as single or poly crystalline silicon and nickel film. This micro tensile tester has been developed for testing various types of materials and dimensions. PZT type actuation is utilized for precise displacement control. The specifications of the PZT actuated micro tensile testers developed are as follows: the volumetric size of the tester is desktop type of 710mm' 200mm' 270mm; the maximum load capacity and the load resolution in this system are IKgf and 0.0152mgf respectively and; the full stroke and the stoke resolution of the PZT actuator are $1000{\mu}m$ and 10nm respectively. Special automatic specimen installing and setting equipment is applied in order to prevent unexpected deformation and misalignment of specimens during handling of specimens for testing. Nonlinearity of the PZT actuator is compensated to linear control input by an inverse compensation method that is proposed in this paper. The strain data is obtained by ISDG method that uses the laser interference phenomenon. To test the reliance of this micro tensile testing machine, a $200{\mu}m$ thickness nickel thin film and SCS (Single Crystalline Silicon) material that is made with the MEMS fabrication process are used.

• Progress in Superconductivity
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• 제7권1호
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• pp.58-63
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• 2005

We investigated the surface oxidation behavior of cube-textured polycrystalline nickel at various oxidation conditions. Cube-textured NiO film was formed on a cube-textured polycrystalline nickel regardless of oxidation conditions but different growth behavior of NiO crystals was observed depending on the oxidation conditions. The introduction of water vapor into $O_2$ did not affect the texture evolution, but rough and porous microstructure was developed. Microstructure of NiO film tends to be denser as the oxygen partial pressure increases. It is interesting that (111) peak of theta - two theta diffraction pattern started to get stronger in air atmosphere and (111) plane became the major texture in the substrate oxidized in high purity argon gas. Small amount of high index crystallographic plane NiO peak crystal was observed when $N_{2}O$ was used as an oxidant while only (200) plane crystal was formed in dry $O_2$ atmosphere. Flat and smooth surface was changed into rough faceted one when ramping rate to oxidation temperature was faster. The grain size of NiO was decreased when the oxygen partial pressure was low. It was also observed that the modification of nickel surface suppressed the development of (200) texture.

• 센서학회지
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• 제24권6호
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• pp.379-384
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• 2015

An infrared image sensor is a core device in a thermal imaging system. The fabrication method of a focal plane array (FPA) is a key technology for a high resolution infrared image sensor. Each pixels in the FPA have $Si_3N_4/SiO_2$ membranes including legs to deposit bolometric materials and electrodes on Si readout circuits (ROIC). Instead of polyimide used to form a sacrificial layer, the feasibility of an amorphous silicon (${\alpha}-Si$) was verified experimentally in a $8{\times}8$ micro-bolometer array with a $50{\mu}m$ pitch. The elimination of the polyimide sacrificial layer hardened by a following plasma assisted deposition process is sometimes far from perfect, and thus requires longer plasma ashing times leading to the deformation of the membrane and leg. Since the amorphous Si could be removed in $XeF_2$ gas at room temperature, however, the fabricated micro-bolomertic structure was not damaged seriously. A radio frequency (RF) sputtered nickel oxide film was grown on a $Si_3N_4/SiO_2$ membrane fabricated using a low stress silicon nitride (LSSiN) technology with a LPCVD system. The deformation of the membrane was effectively reduced by a combining the ${\alpha}-Si$ and LSSiN process for a nickel oxide micro-bolometer.

• 한국표면공학회지
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• 제40권2호
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• pp.82-90
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• 2007

Crevice corrosion is the accelerated attack occurred in the occluded cell under a crevice on the metal surface. Crevice corrosion behaviors of nickel-based alloys such as Alloy 600 and Alloy 690 were investigated in acidic solution with different chloride ion concentrations. Tests were carried out using the specially designed crevice cell with a very narrow Luggin capillary assembly to measure the potential inside the crevice. It is believed that crevice corrosion in active/passive system like nickel-based alloys has much to do with the properties of passive film and its repassivation characteristics, investigated by the capacitance measurement and by the abrading electrode technique, respectively. An attempt was made to elucidate the relationship between crevice corrosion behaviors, properties of passive film and its repassivation kinetics. Results showed that repassivation rate parameter $n1{\leq}0.6$ and/or $n2{\leq}0.5$ indicated the possible occurrence of crevice corrosion.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.25.2-25.2
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• 2011

Recently, thin film capacitors used for vehicle inverters are small size, high capacitance, fast response, and large capacitance. But its applications were made up of liquid as electrolyte, so its capacitors are limited to low operating temperature range and the polarity. This research proposes using Ni-P alloys by electroless plating as the electrode instead of liquid electrode. Our substrate has a high aspect ratio and complicated shape because of anodic aluminum oxide (AAO). We used AAO because film thickness and effective surface area are depended on for high capacitance. As the metal electrode instead of electrolyte is injected into AAO, the film capacitor has advantages high voltage, wide operating temperature, and excellent frequency property. However, thin film capacitor made by electroless-plated Ni on AAO for full-filling into etched tunnel was limited from optimizing the deposition process so as to prevent open-through pore structures at the electroless plating owing to complicated morphological structure. In this paper, the electroless plating parameters are controlled by temperature in electroless Ni plating for reducing reaction rate. The Electrical properties with I-V and capacitance density were measured. By using nickel electrode, the capacitance density for the etched and Ni electroless plated films was 100 nFcm-2 while that for a film without any etch tunnel was 12.5 nFcm-2. Breakdown voltage and leakage current are improved, as the properties of metal deposition by electroless plating. The synthesized final nanostructures were characterized by scanning electron microscopy (SEM).

• 한국표면공학회지
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• 제37권2호
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• pp.76-79
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• 2004

Nickel chloride coated protein chip plate was developed by using a spin coating method. The ability of histidine tagged protein adsorption was investigated at various solvents. The surface of plate has a large aggregated nickel complex with high density in water. However, the surface of plate has a very small size of aggregated nickel complex with low density in isopropanol. The ability of protein adsorption decreased as increasing the size of alkyl chain in various alcohol solvents. The mechanism on the ability of protein adsorption at the plate surface is discussed.

• 마이크로전자및패키징학회지
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• 제14권3호
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• pp.21-27
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• 2007

이방성 전도필름(ACF) 접합에 사용되는 니켈 범프를 무전해 및 전해 도금법으로 제작한 다음, 이 범프들의 기계적 특성과 충격안전성을 압축시험, 범프전단시험, 낙하충격시험을 통하여 연구하였다. Nano indenter를 이용한 압축시험에서 얻은 하중-변형량 데이터를 변환시켜 니켈범프의 응력-변형량 곡선을 구하였다. 전해 니켈 범프는 무전해 니켈 범프에 비해 매우 작은 탄성한계응력과 탄성계수를 나타냈었다. 무전해 니켈 범프의 탄성한계응력과 탄성계수가 각각 600-800MPa, $9.7{\times}10^{-3}MPa/nm$인 반면 전해 니켈 범프의 경우에는 각각 70MPa, $7.8{\times}10^4MPa/nm$이었다. 범프전단 시험에서 무전해 니켈 범프는 소성변형이 거의 일어나지 않고 낮은 전단하중에서 범프가 패드 층에서 튕기듯이 떨어져 나간 반면 전해 니켈 범프는 큰 소성변형을 일으키며 범프가 잘려나갔으며 높은 전단하중을 보여주었다. 낙하충격시험 결과 ACF 플립칩 방법으로 본딩한 무전해 및 전해 범프 모두 높은 충격 신뢰성을 보였다.

• Progress in Superconductivity
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• 제7권2호
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• pp.145-151
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• 2006

Nickel and nickel-tungsten alloy were electroplated on a cold rolled and heat treated copper(Cu) substrate. 4 mm-thick high purity commercial grade Cu was rolled to various thicknesses of 50, 70, 100 and 150 micron. High reduction ratio of 30% was applied down to 150 micron. Rolled texture was converted into cube texture via high temperature heat treatment at $400-800^{\circ}C$. Grain size of Cu was about 50 micron which is much smaller compared to >300 micron for the Cu prepared using smaller reduction pass of 5%. 1.5 km-long 150 micron Cu was fabricated with a rolling speed of 33 m/min and texture of Cu was uniform along length. Abnormal grain growth and non-cube texture appeared for the specimen anneal above $900^{\circ}C$. 1-10 micron thick Ni and Ni-W film was electroplated onto an annealed cube-textured Cu or directly on a cold rolled Cu. Both specimens were annealed and the degree of texture was measured. For electroplating of Ni on annealed Cu, Ni layer duplicated the cube-texture of Cu substrate and the FWHM of in plane XRD measurement for annealed Cu layer and electroplated layer was $9.9^{\circ}\;and\;13.4^{\irc}$, respectively. But the FWHM of in plane XRD measurement of the specimen which electroplated Ni directly on cold rolled Cu was $8.6^{\circ}$, which is better texture than that of nickel electroplated on annealed Cu and it might be caused by the suppression of secondary recrystallization and abnormal grain growth of Cu at high temperature above $900^{\circ}C$ by electroplated nickel.

• 한국세라믹학회지
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• 제13권2호
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• pp.8-16
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• 1976

The conductive transparent film is prepared by spraying thin salt solution. In stannic chloride solution as a base solution, various dopants such as Al, Co, Cu and Ni were dissolved respectively as a chloride state and then the films were made by spraying solutions on hot glass plates. The properties of them were compared with those of the stannic salt single component film. The films doped with copper oxide and nickle oxide were improved by decreasing their sheet resistivity and temperature coefficient of resistivity. In comparison with the sheet resistivity and temperature coefficient of resistivity of stannic oxide single component film, being 2.5 K ohm/$\textrm{cm}^2$ and -1650ppm/$^{\circ}C$ respectively, its values of the film containing 15 mol % of copper oxide and formed at 40$0^{\circ}C$ were 2.5K ohm/$\textrm{cm}^2$ and -920ppm/$^{\circ}C$ respectively. The film containing 15 mol % of nickel oxide and formed at 50$0^{\circ}C$ has shown its sheet resistivity and temperature coefficient 0.7 K ohm/$\textrm{cm}^2$ and -940ppm/$^{\circ}C$ respectively.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.204-210
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• 2012

니켈에 양극산화법을 적용하여 기존의 선행연구에서 보고되었던 nm 단위의 두께를 극복하고 최대 2.3 ${\mu}m$ 두께의 산화니켈 박막을 제조하였다. 전해질은 에틸렌글리콜을 용매로 사용하였으며 $F^-$ 이온을 공급하기 위해 $NH_4F$를 첨가하였다. 전압을 40, 60, 80 V로 변화시키며 최대 12시간까지 양극산화반응을 진행하였으며 시간과 전압을 증가시킴에 따라 산화니켈 박막의 두께도 증가하였다. 그러나 80 V 전압에서는 급격한 산화 작용에 따른 니켈의 파괴가 나타났다. XRD 분석 결과 양극산화에 의해 NiO가 생성되었음을 확인하였다.