• The monthly packaging world
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• s.209
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• pp.58-63
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• 2010

• Proceedings of the Korean Magnestics Society Conference
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• 2000.05a
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• pp.72-73
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• 2000

• Proceedings of the Korean Printing Society Conference
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• 1998.10a
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• pp.22-30
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• 1998

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.72-73
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• 2010

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.347.1-347.1
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• 2016

Screen printing is commonly used to form the electrode for crystalline silicon solar cells. However, it has caused high resistance and low aspect ratio, resulting in decrease of conversion efficiency. Accordingly, Ni/Cu/Ag plating method could be applied for crystalline silicon solar cells to reduce contact resistance. For Ni/Cu/Ag plating, laser ablation process is required to remove anti-reflection layers prior to the plating process, but laser ablation results in surface damage and then decrease of open-circuit voltage and cell efficiency. Another issue with plating process is ghost plating. Ghost plating occurred in the non-metallized region, resulting from pin-hole in anti-reflection layer. In this paper, we investigated the effect of Ni/Cu/Ag plating on the electrical properties, compared to screen printing method. In addition, phosphoric acid layer was spin-coated prior to laser ablation to minimize emitter damage by the laser. Phosphorous elements in phosphoric acid generated selective emitter throughout emitter layer during laser process. Then, KOH treatment was applied to remove surface damage by laser. At this step, amorphous silicon formed by laser ablation was recrystallized during firing process and remaining of amorphous silicon was removed by KOH treatment. As a result, electrical properties as Jsc, FF and efficiency were improved, but Voc was lower than screen printed solar cells because Voc was decreased due to surface damage by laser process. Accordingly, we expect that efficiency of solar cells could be improved by optimization of the process to remove surface damage.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.1
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• pp.15-24
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• 2010

Photovoltaic solar cells are all in the incident because they are not converted into electrical energy, high-efficiency solar cells in order to reduce the loss of elements must be. Significant factor in the loss of solar cells, optical loss and electrical loss can be divided into. Optical losses occur when the sun will be joined on the surface of the reflection, the shadow loss due to electrodes, and the losses are in the solar wavelengths. Commercialization is currently the most common solar cells on the front of the light incident on the electrode is formed. Therefore, the shadow caused by the electrode to cover the dead area of the sun, due to factors that hinder the absorption of sunlight which is shadowing them and conversion efficiency of solar cells is the inhibition factor. These barriers to eliminate the electrode linewidth reduces the shadowing to reduce, but simply of the electrode line width is reduced electrode area by reducing the series resistance elevates this because to improve the electrode Aspect ratio(height/width) to increase Ag development of paste is required. In this study, aspect ratio of screen-printing method to increase the electrode Ag paste composition of the binder for the characterization of rheology in the shadow of the electrode by reducing the optical loss of the photoelectric conversion efficiency of solar cells to boost the performance measures was. Properties and printability of the paste, the binder resin sintered characteristics that affect the thermal properties are excellent with a good screen printability acrylic resin, ethyl cellulose, using a resin were evaluated. Prepared paste rheology properties, was formed to evaluate the electrode conductivity and aspect ratio.

• Journal of the Korean Ceramic Society
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• v.39 no.5
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• pp.467-472
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• 2002

Long Carbon Nanotubes(CNTs) were cut by diamond lapping film followed by observation using SEM. The paste was prepared by mixing shortened CNT powder, ${\alpha}$-terpineol used as a solvent, and ethylcellulose as a binder. This paste was deposited on glass substrate by screen printing and extruded by syringe. After screen printing, several post-treatments were performed to control the alignment of CNTs perpendicular to the substrate. The deposited CNTs were scratched by sand paper or diamond lapping film. It was also treated by attachment followed by an immediate detachment using the adhesive tape. SEM observation indicates that excellent vertical alignment of CNTs could be achieved by simple post-treatments from the screen printed-CNTs paste. Similar alignment of CNTs is also observed in the as-extruded CNTs paste.

• Journal of Korean Library and Information Science Society
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• v.35 no.2
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• pp.31-45
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• 2004

The purpose of this study is analyze physical and textual characteristics of the fold screen with Gosi(고시), tour ancient poems own by Beopjusa temple(법주사) in Mt. Sokrisan(속리산). The calligraphic specimen of this fold screen is written by King Seonjo(선조), and it seems to be made by between 1725 and 1758. On the view of physical point, the size of the fold screen is 190.0cm high, and 67.2cm wide each fold. And its format is made by 8 fold screen and its calligraphic style is a ‘cursive’ style. It was printed by wood block printing with chinese ink on the Geonji(견지). On the view of textual point, the fold screen of Gosi(고시) is consist of four ancient poems, and its content is describe to yearning for the appearance of the true gentleman possessed with high principles and virtue. And the four ancient poems is arranged by a well organized passage.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.1
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• pp.47-53
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• 2010

In this study, analyses on the stencil printing using solder paste were carried out. The key design parameters in the stencil printing process are printing conditions, stencil design, and solder paste properties. Among these parameters, the effects of physical properties of solder paste such as viscosity, surface tension, and contact angle on the stencil printing process were investigated. The analyses were performed for simple geometry and boundary conditions. In the analysis, solder paste was pushed into a stencil hole by pressure instead of printer pad. Considering the geometry and computational efficiency, axisymmetric analyses were adopted. A commercial software (COMSOL), which is well known in the area of micro-fluids analysis, was used. From the results, it was shown that viscosity of solder paste had an effect on the filling speed, while surface tension and contact angle had an effect on the filling shape.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.19.1-19.1
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• 2010

The process of manufacturing printed electronics using printing technology is attracting attention because its process cost is lower than that of the conventional semiconductor process. This technology, which offers both a lower cost and higher productivity, can be applied in the production of organic TFT (thin film transistor), solar cell, RFID(radio frequency identification) tag, printed battery, E-paper, touch screen panel, black matrix for LCD(liquid crystal display), flexible display, and so forth. In general, in order to implement printed electronics, narrow width and gap printing, registration of multi-layer printing by several printing units, and printing accuracy of under $20\;{\mu}m$ are all required. These electronic products require high precision to the degree of tens of microns - in a large area with flexible material, and mass productivity at low cost. As such, the roll-to-roll printing process is attracting attention as a mass production system for these printed electronic devices. For the commercialization of this process, two basic electronic ink technologies, such as conductive ink and polymers, and printing equipment have to be developed. Therefore, this paper addressed basis design and test to develop fine patterning equipment employing the roll-to-roll printing equipment and electronic ink.