• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.246-251
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• 2013

Screen printing is commonly used to form the front/back electrodes in silicon solar cell. But it has caused high resistance and low aspect ratio, resulting in decreased conversion efficiency in solar cell. Recently the plating method has been combined with screen-printed c-Si solar cell to reduce the resistance and improve the aspect ratio. In this paper, we investigated the effect of light induced silver plating with screen-printed c-Si solar cells and compared their electrical properties. All wafers were textured, doped, and coated with anti-reflection layer. The metallization process was carried out with screen-printing, followed by co-fired. Then we performed light induced Ag plating by changing the plating time in the range of 20 sec~5min with/without external light. For comparison, we measured the light I-V characteristics and electrode width by optical microscope. During plating, silver ions fill the porous structure established in rapid silver particle sintering during co-firing step, which results in resistance decrease and efficiency improvement. The plating rate was increased in presence of light lamp, resulting in widening the electrode with and reducing the short-circuit current by shadowing loss. With the optimized plating condition, the conversion efficiency of solar cells was increased by 0.4% due to decreased series resistance. Finally we obtained the short-circuit current of 8.66 A, open-circuit voltage of 0.632 V, fill factor of 78.2%, and efficiency of 17.8% on a silicon solar cell.

• Korean Journal of Materials Research
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• v.12 no.6
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• pp.499-507
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• 2002

The carbon nanotube emitters for field emission displays were fabricated by using screen printing techniques. The pastes for screen printing are composed of organic binders, carbon nanotubes (multiwalled or singlewalled), and some additive materials. The pastes were printed on Cr-coated/Ag-printed soda-lime glass substrates. From the I-V characteristics, the turn-on field of SWNT was lower than that of MWNT. The decrease in the mesh size of screen masks (i.e. increase in the opening size of the screen mesh) resulted in decreasing the turn-on field and increasing the electron emission current. When the carbon nanotubes were mixed with silver pastes, silver powders appeared to contribute to the vertically aligning of carbon nanotubes on a glass.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.2
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• pp.57-67
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• 2010

The double layer screen plate tensioned with two sheets screen mesh is more thicker than that of one screen sheet. The double layer screen plate piled up with two sheets screen 200# or overlapped with a sheet screen 110# and a sheet screen 305# is more thicker than single layer screen plate with one sheet screen 420#. As the screen plate composed of two sheets screen has more accumulated ink capacity than one sheet of screen, printing printed with it has a good plasticity. And the single layer screen plate that accumulate a small quantity of ink has an excellent representation than the double layer screen plate but lower plasticity.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.2
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• pp.69-74
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• 2017

Effect of post-annealing treatment times at $200^{\circ}C$ on the peel strength of screen-printed Ag film/polyimide substrate were systematically investigated by $180^{\circ}$ peel test for thermal reliability assessment of printed interconnect. Initial peel strength around 16.7 gf/mm increased up to 29.4 gf/mm after annealing for 24hours, and then sharply decreased to 22.3, 3.6, 0.6, and 0.1 gf/mm after 48, 100, 250, and 500 hours, respectively. Ag-O-C chemical bonding as well as binder organic bridges formations seemed to be responsible for interfacial adhesion improvement after the initial annealing treatment, while excessive Cu oxide formation at Cu/Ag interface seems to be closely related to sharp decrease in peel strength for longer annealing times.

• Journal of Powder Materials
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• v.19 no.5
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• pp.343-347
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• 2012

In this study, an oxygen plasma treatment was used as a low temperature debinding method to form a conductive copper feature on a flexible substrate using a direct printing process. To demonstrate this concept, conductive copper patterns were formed on polyimide films using a copper nanoparticle-based paste with polymeric binders and dispersing agents and a screen printing method. Thermal and oxygen plasma treatments were utilized to remove the polymeric vehicle before a sintering of copper nanoparticles. The effect of the debinding methods on the phase, microstructure and electrical conductivity of the screen-printed patterns was systematically investigated by FE-SEM, TGA, XRD and four-point probe analysis. The patterns formed using oxygen plasma debinding showed the well-developed microstructure and the superior electrical conductivity compared with those of using thermal debinding.

• Journal of the Korean Home Economics Association
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• v.38 no.9
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• pp.119-130
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• 2000

The purpose of this study was to confirm the possibility of screen printing with Natural dyes. The coloring matter such as sappan wood was used in order to obtain the colorant powder through the processes of extraction, low pressure concentration and the spray dry. After the screen printing on silk and cotton fabrics with colorant, K/S value changes of color and color fastness were measured. The main resets were as follows : 1. The viscosity of printing thickeners of sappan wood powder was about 15,200 cps, and the highest K/S value of the fabrics printed with sappan wood was obtained at 90$\pm$2$\^{C}$ of steaming temperature and 80 minutes of steaming time. 2. For the fabrics printed with sampan wood, adding of urea was not effective, since the more the concentration of urea increased, the more K/S values decreased. 3. For the natural dyes printing, the more the concentration of colorants increased, the more K/S values increased. In general, the K/S values of the printed fabrics were higher when treated with mordants rather than without mordants. Specifically, the λmax sappan wood was 520∼570 nm, and the K/S value was highest when treated with Cu mordant and lowest when treated with Sn. 4. Generally, the color fastness was relatively fair.

• Journal of Powder Materials
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• v.18 no.5
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• pp.423-429
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• 2011

Thermoelectric-thick films were fabricated by using a screen printing process of n and p-type bismuth-telluride-based pastes. The screen-printed thick films have approximately 30 ${\mu}m$ in thickness and show rough surfaces yielding an empty gap between an electrode and the thick film. The gap might result in an increase of an electrical resistivity of the fabricated thick-film-type thermoelectric module. In this study, we suggest a conductive metal coating onto the surfaces of the screen-printed paste in order to reduce the contact resistance in the module. As a result, the electrical resistivity of the thermoelectric module having a gold coating layer was significantly reduced up to 30% compared to that of a module without any metal coating. This result indicates that an introduction of conductive metal layers is effective to decrease the contact resistivity of a thick-film-typed thermoelectric module processed by screen printing.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1519-1521
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• 2007

In this work, a coplanar-type plasma flat fluorescent lamp having cross type of electrode was fabricated by screen printing and sealing technique. Cross type of electrode with a dielectric layer were screen-printed on a rear glass plate, and then fired at $550^{\circ}C$. Phosphor was printed on and fired at $450^{\circ}C$. Finally, the lamp was sealed by frit glass at $450^{\circ}C$. The lamp of cross electrode type was studied depending on the electrode gap and the thickness of dielectric layer.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1305-1307
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• 2007

We show that the electrical properties of organic thinfilm transistors(OTFTs) can be enhanced by controlling the morphology of interface between screen printed electrodes and gate dielectrics. Modified surface of the insulator layer($SiO_2$) affect on the interface energy of electrode on $SiO_2$ layer. Contact angle measurement and FT-IR spectrum shows that the interface is properly modified. OTFTs device with high efficiency has been realized through modification of interface layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.5
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• pp.456-461
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• 2007

In this study, a surface treatment method using accelerated Ar ions was experimented for exposing the carbon nanotubes (CNT) from the screen-printed CNT paste. After making a cathode electrode on the glass substrate, photo sensitive CNT paste was screen-printed, and then back-side was exposed by UV light. Then, the exposed CNT paste was selectively remained by development. After post-baking, the remained CNT paste was bombarded by accelerated Ar ions for removing some binders and exposing only CNTs. As results, the field emission characteristics were strongly depended on the accelerating energy, bombardment time, and the power of RF plasma ion source. When Ar ions accelerated with 100 eV energy from the 100 W RF plasma source are bombarded on the CNT paste surface for 10 min, the emission level and the uniformity were best.