• Journal of Magnetics
• /
• v.4 no.1
• /
• pp.22-25
• /
• 1999

Recently we reported the evolutionary transition from the positive magnetoresistance to the negative was discovered in the transverse configuration as the thickness of permalloy film increases. The discovered peculiarities of positive magnetoresistance phenomenal were explained in the framework of the uniform rotation model of the film magnetization reversal.

• Journal of the Semiconductor & Display Technology
• /
• v.16 no.3
• /
• pp.59-64
• /
• 2017

As the demand on displays increases, new thin-film transistors such as metal oxide transistor are continuously being invented. When designing a circuit consisting of such new transistors, a new transistor model based on proper charge transport mechanisms is needed for each of them. In this paper, a modeling framework which enables to choose charge transport mechanisms that are limited to certain operation regions and assemble them into a transistor model instead of making an integrated transistor model dedicated to each transistor. The framework consists of a graphic user interface to choose charge transport models and a current calculation part, which is also implemented in AIM-SPICE for circuit simulation.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.49 no.2
• /
• pp.8-17
• /
• 2012

In this paper we proposes a new framework to obtain 3D shape information of thin film rapidly. The conventional equipments based on reflectometry are not suitable for obtaining 3D overall shape information of thin film rapidly since they require more than 30 minutes to measure the absolute thickness for 170 points. The proposed framework is based on an image analysis method that extracts contour lines from interference fringes images using Canny edge detector. The absolute thickness for contour lines are measured and then a height map from the contour lines is obtained by interpolation using Borgefors distance transformation. The extracted height map is visualized using the DirectX 3D terrain rendering method. The proposed framework can provide 3D overall shape information of thin film in about 5 minutes since relatively small number of real measurement for contour lines is required.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.25 no.4
• /
• pp.266-270
• /
• 2016

We present a useful and practical manufacturing technique that enables the structural conversion of delicate as-grown nanostructures to more beneficial and robust thin-film frameworks through controlled mechanical rolling. Functional nanostructures such as carbon nanotubes grown through chemical vapor deposition in a vertically aligned and very loosely packed manner, and thus difficult to manipulate for subsequent uses, can be prepared in an array of thin blades by patterning the growth catalyst layer. They can then be toppled as dominos through precisely controlled mechanical rolling. The nanostructures formulated to horizontally aligned thin films are much more favorable for device applications typically based on thin-film configuration. The proposed technique may broaden the functionality and applicability of as-grown nanostructures by converting them into thin-film frameworks that are easier to handle and more durable and favorable for fabricating thin-film devices for electronics, sensors, and other applications.

• Journal of Sensor Science and Technology
• /
• v.18 no.2
• /
• pp.110-115
• /
• 2009

Polystyrene (PS) microspheres were used to good advantage as a template material to prepare macroporous $TiO_2$ thin films. This is enabled to run the thermal decomposition of the PS without the collapsing of the 3-D macroporous framework during the calcination step. $TiO_2$ thin films were deposited onto the colloidal templated substrates at room temperature by RF sputtering, and then samples were thermally treated at $450^{\circ}C$ for 40.min in air to remove the organic colloidal template and induce crystallization of the $TiO_2$ film. The macroporous $TiO_2$ thin film exhibited a quasi-ordered partially hexagonal close-packed structure. Burst holes, estimated to be formed during PS thermal decomposition, are seen as the hemisphere walls. the inner as well as the outer surfaces of the hollow hemispheres formed by the method of thermal decomposition can be easily accessed by the diffusing gas species. As a consequence, the active surface area interacting with the gas species is expected to be enlarged about by a factor of fourth as large as compared to that of a planar films. Also the thickness at neighboring hemisphere could be controlled a few nm thickness. If the acceptor density becomes as large that depletion width reaches those thickness, the device is in the pinch off-situation and a strong resistance change should be observed.

• Membrane Journal
• /
• v.31 no.1
• /
• pp.35-51
• /
• 2021

Advancements in thin-film nanocomposite (TFN) membrane technology for nanofiltration is crucial for removing pollutants from natural resources. In recent years, various metal-organic framework (MOF) modifications have been tested to overcome the drawbacks that are inevitable with conventional thin-film composite (TFC) and TFN membranes. In general, MIL-101(Cr), UiO-66, ZIF-8, and HKUST-1 [Cu3(BCT2)] are MOFs that were proven to exhibit excellent membrane performance in terms of solvent permeability and solute rejection; their respective studies are reviewed in this article. Other novelties, such as the simultaneous use of different MOFs and unique MOF layering techniques (e.g., dip-coating, spray pre-disposition, Langmuir-Schaefer film, etc.) are also discussed as they present alternate solutions for membrane enhancement and/or preparation convenience. Not only are these MOF-modified TFN membranes frequently shown to improve separation performance from their respective TFC and TFN membranes, but many reports also explain their potential for a cost-effective and environmentally friendly process. In this review the thin film nanocomposite nanofiltration membrane is discussed.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.5
• /
• pp.2038-2047
• /
• 2011

This paper presents a framework for production planning for a Slim MES(Manufacturing Execution System) of module operations in TFT-LCD(Thin Film Transistor-Liquid Crystal Display) production lines. There are differences in the line configurations and functions among the module operations in the TFT-LCD production systems. This paper presents the framework for the customized MES reflecting these differences. First, a production process is figured out through the analysis of the TFT-LCD module operations. Next, a mathematical modeling is presented reflecting the constraints of shop floors and an optimal schedule is presented through a case example. And a scheduling process using the dispatching rules reflecting the status of shop floors is presented and the performances are measured and compared. Finally, a design process for the Slim MES framework is presented.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.304-305
• /
• 2013

We report a positive exchange bias (HE) in thinmultilayered filmscontaining nano-oxide layer. The positive HE, obtained for our system results from an antiferromagnetic coupling between the ferromagnetic (FM) CoFe and the antiferromagnetic (AFM) CoO layers, which spontaneously form on top of the nano-oxide layer (NOL). The shift in the hysteresis loop along the direction of thecooling field and the change in the sign of exchange bias are evidence of antiferromagnetic interfacial exchange coupling between the CoO and CoFe layers. Our calculation indicates that uncompensated oxygen moments in the NOL results in antiferromagnetic interfacial exchange coupling between the CoO and CoFe layers. One of the interesting features observed with our system is that it displays the positive HE even above the bulk Neel temperature (TN) of CoO. Although the positive HEsystem has a different AFM/FM interfacial spin structure compare to that of the negative HE one, the results of the angular dependence measurements show that the magnetization reversal mechanism can be considered within the framework of the coherent rotation model.

• Membrane Journal
• /
• v.29 no.3
• /
• pp.130-139
• /
• 2019

Various two-dimensional nano materials such as graphene, zeolite, and metal-organic framework have been utilized to develop an ultra-thin high-performance membrane for water purification, gas separation, and so on. Particularly, in the case of graphene oxide, synthesis methods and thin film coating techniques have been accumulated and established since early 2000s, therefore graphene oxide has been rapidly applied to membrane field. The multi-layered graphene oxide thin film can filter molecules separately by the molecular sieving of interlayer spacing between adjacent layers, and it is also possible to separate various materials depending on the surface functional groups or the degree of interaction to intercalated materials. This review mainly focuses on the nanofiltration application of graphene oxide. The major factors affecting the separation performance of graphene oxide membrane in solvent are summarized and other technical elements required for the commercialization of graphene oxide membranes will be discussed including stability issue and fabrication method.

• Journal of Periodontal and Implant Science
• /
• v.30 no.1
• /
• pp.167-180
• /
• 2000

The present study evaluated the effects of guided tissue regeneration using biodegradable membrane, with and without calcium-phosphate thin film coated deproteinated bone powder in beagle dogs. Contralateral fenestration defects(6 × 4 mm) were created 4 mm apical to the buccal alveolar crest on maxillary canine teeth in 5 beagle dogs. Ca-P thin film coated deproteinated bone powder was implanted into one randomly selected fenestration defect(experimental group). Biodegradable membranes were used to provide bilateral GTR. Tissue blocks including defects with overlying membranes and soft tissues were harvested following a four- & eight-week healing interval and prepared for histologic analysis. The results of this study were as follows. 1.......The regeneration of new bone, new periodontal ligament, and new cementum was occurred in experimental group more than control group. 2.......The collapse of biodegradable membranes into defects were showed in control group and the space for regeneration was diminished. In experimental group, the space was maintained without collapse by graft materials. 3........In experimental group, the graft materials were resorbed at 4 weeks after surgery and regeneration of bone surrounding graft materials was occurred at 8 weeks after surgery. 4.......Biodegradable membranes were not resorbed at 4 weeks and partial resorption was occurred at 8 weeks but the framework and the shape of membranes were maintained. No inflammation was showed at resorption. In conclusion, the results of the present study suggest that Ca-P thin film coated deproteinated bone powder has adjunctive effect to GTR in periodontal fenestration defects. Because it has osteoconductive property and prohibit collapse of membrane into defect, can promote regeneration of much new attachment apparatus.