• 태양에너지
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• 제17권1호
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• pp.17-26
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• 1997

단결정 실리콘 태양전지는 PESC(Passivated Emitter Solar Cell), PERC(Passivated Emitter and Rear Cell), Point Contact Cell, PERL(Passivated Emitter and Rear Locally-Diffused Cell) 형태로 기술적인 발전을 해왔다. BCSC(Buried Contact Solar Cell)는 낮은 제조 단가로 높은 효율을 얻을 목적으로 개발되었으며 개량된 형태인 DSBC(Double Sided Buried Contact Cell)는 양면으로 빛을 흡수할 수 있는 장점이 있다.

• 한국안광학회지
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• 제20권4호
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• pp.455-462
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• 2015

목적: 친수성 콘택트렌즈 정점굴절력 측정 방식중 하나인 wet cell 측정법을 활용한 국산화 측정 홀더와 프로그램 개발에 관한 연구를 위해 현재 사용되어지고 있는 Poster wet cell 홀더와 함수율별 굴절력의 측정값을 비교 분석하였다. 방법: 안경원에서 사용 중인 기존 제품과 새롭게 개발된 국산제품에 식염수를 채워 넣고 소프트콘택트렌즈의 굴절력을 측정하였다. 실험에 사용한 친수성 콘택트렌즈는 안경원에서 많이 사용되고 있는 국내산 렌즈를 사용하였으며, 함수율별과, 구면굴절력별로 분류하여 각각 실험하였다. 결과: wet cell 방식으로 콘택트렌즈 굴절력 측정 시 새롭게 개발한 홀더의 경우 자동렌즈미터를 사용하여 굴절력을 측정한 결과 -3.00 D에서 함수율 38%는 -3.01 D, 함수율 45%는 -3.00 D, 함수율 58%는 -2.98 D로 측정되었으며, Poster wet cell 홀더를 사용하여 렌즈를 측정한 결과 -3.00 D에서 함수율 38%는 -3.60 D, 45%는 -3.06 D, 58%는 -2.46 D로 각각 측정되었다. 결론 : 고함수율에서 굴절력 측정값은 wet cell 방식의 두 홀더 모두 낮게 나타났으며, 새롭게 개발된 홀더와 프로그램을 통한 자동렌즈미터의 측정값이 기존의 Poster soft contact lens wet cell 측정방식에 비해 더 정확한 굴절력 측정 결과를 나타내었다.

• Parasites, Hosts and Diseases
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• 제46권4호
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• pp.217-221
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• 2008

Free-living Naegleria fowleri leads to a fatal infection known as primary amebic meningoencephalitis in humans. Previously, the target cell death could be induced by phagocytic activity of N. fowleri as a contact-dependent mechanism. However, in this study we investigated the target cell death under a non-contact system using a tissue-culture insert. The human microglial cells, U87MG cells, co-cultured with N. fowleri trophozoites for 30 min in a non-contact system showed morphological changes such as the cell membrane destruction and a reduction in the number. By fluorescence-activated cell sorter (FACS) analysis, U87MG cells co-cultured with N. fowleri trophozoites in a non-contact system showed a significant increase of apoptotic cells (16%) in comparison with that of the control or N. fowleri lysate. When U87MG cells were co-cultured with N. fowleri trophozoites in a non-contact system for 30 min, 2 hr, and 4 hr, the cytotoxicity of amebae against target cells was 40.5, 44.2, and 45.6%, respectively. By contrast, the cytotoxicity of non-pathogenic N. gruberi trophozoites was 10.2, 12.4, and 13.2%, respectively. These results suggest that the molecules released from N. fowleri in a contact-independent manner as well as phagocytosis in a contact-dependent manner may induce the host cell death.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.91.2-91.2
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• 2010

The use of plated front contact for metallization of silicon solar cell may alternative technologies as a screen printed and silver paste contact. This technologies should allow the formation of contact with low contact resistivity a high line conductivity and also reduction of shading losses. The better performance of Ni/Cu contacts is attributed to the reduced series resistance due to better contact conductivity of Ni with Si and subsequent electroplating of Cu on Ni. The ability to pattern narrower grid lines for reduced light shading combined with the lower resistance of a metal silicide contact and improved conductivity of plated deposit. This improves the FF as the series resistance is deduced. This is very much required in the case of low concentrator solar cells in which the series resistance is one of the important and dominant parameter that affect the cell performance. A selective emitter structure with highly dopes regions underneath the metal contacts, is widely known to be one of the most promising high-efficiency solution in solar cell processing. This paper using selective emitter structure technique, fabricated Ni/Cu plating metallization cell with a cell efficiency of 17.19%.

• 한국정밀공학회지
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• 제24권5호
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• pp.118-126
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• 2007

A finite element simulation model was developed for the performance optimization of a closed type air-cell mattress used for the ulcer prevention. An H-model with material properties of human flesh and kinematic joints were used for the calculation of the body contact pressure. The material property of rubber air-cell was evaluated by tensile test of standard specimen. We evaluated the body contact pressure distribution after laying human model on the inflated air-cell mattress. It was found that the body contact pressure was dependent on cell height. but hardly affected by the thickness of the rubber in a cell.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.43.1-43.1
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• 2010

In the crystalline silicon solar cells, the full area aluminum_back surface field(BSF) is routinely achieved through the screen-printing of aluminum paste and rapid firing. It is widely used in the industrial solar cell because of the simple and cost-effective process to suppress the overall recombination at the back surface. However, it still has limitations such as the relatively higher recombination rate and the low-to-moderate reflectance. In addition, it is difficult to apply it to thinner substrate due to wafer bowing. In the recent years, the dielectric back-passivated cell with local back contacts has been developed and implemented to overcome its disadvantages. Although it is successful to gain a lower value of surface recombination velocity(SRV), the series resistance($R_{series}$) becomes even more important than the conventional solar cell. That is, it is a trade off relationship between the SRV and the $R_{series}$ as a function of the contact size, the contact spacing and the geometry of the opening. Therefore it is essential to find the best compromise between them for the high efficiency solar cell. We have investigated the optimal design for the local back contact by using PC1D simulation.

• 한국전기전자재료학회논문지
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• 제17권2호
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• pp.121-126
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• 2004

In this paper, the effects of the ozone oxidation of the landing polycrystalline silicon on the cell contact resistance of the DRAM device were studied. For this study, the ozone oxidation of the landing polycrystalline silicon layer was performed under various conditions, which was followed by the normal DRAM processes. Then, the cell contact resistance and $t_{WR}$ (write recovery time) of the devices were measured and analyzed. The experimental results showed that the cell contact resistance was more significantly increased for higher temperature of oxidation, longer time of oxidation, and higher concentration of ozone in the oxidation furnace. In addition, the TEM cross-sectional micrographs clearly showed that the oxide layer at the interface between the landing polycrystalline silicon layer and the plug polycrystalline silicon layer was increased by the ozone oxidation. Furthermore, the rate of the device failure due to too large write recovery time was also found to be well correlated with the increase of the cell contact resistance.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.175-178
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• 2003

Mechanical behavior of a fuel stack was studied by the orthotropic material model. The fuel stack is mainly composed of bipolar plate (BP), gasket, end plate, membrane electrolyte assembly (MEA), and gas diffusion layer (GDL). Each component is fastened with a suitable pressure. It is very important to maintain a suitable contact pressure of BP, because it affects the efficiency of the fuel cell. This study compared mechanical behavior of various fastening types of the fuel cell stack. Bar, band, and modified band fastening type are used. The band fastening type showed that it reduces total volume of the cell, but it does not improve the contact pressure distribution of each BP. The modified band fastening type was designed by considering the deformations of band fastening type, and it showed a good enhancement of contact pressure distribution.

• 한국전기전자재료학회논문지
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• 제17권12호
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• pp.1352-1355
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• 2004

We have applied front contact metallization of plated nickel and copper for high efficiency passivated emitter rear contact(PERC) solar cell. Ni is shown to be a suitable barrier to Cu diffusion as well as desirable contact metal to silicon. The plating technique is a preferred method for commercial solar cell fabrication because it is a room temperature process with high growth rates and good morphology. In this system, the electroless plated Ni is utilized as the contact to silicon and the plated Cu serves as the primary conductor layer instead of traditional solution that are based on Ti/Pd/Ag contact system. Experimental results are shown for over 20 % PERC cells with the Plated Ni/Cu contact system for good performance at low cost.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.172-176
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• 1995

Schemes to trap weakly absorbed light into the cell have played an important role in improving the efficiency of both amorphous and crystlline silicon solar cells. One class of scheme relies on randomizing the direction of light within the cell by use of Lambertian(diffuse)surfaces. A second class of scheme relies on the use fo well defined geometrical features to control the direction of light wihin the cell, Widly used geometrical features in crystalline silicon solar cells are the square based pyramids and V-shaped grooves formed in (100) orientated surfaces by intersecting(III) crystallographic planes exposed by anisotropic etching. 18.5% conversion efficiency of Buried Contact Solar Cell with pyramidally textured surface has been achieved. 18.5% efficiency of silicon solar cell is one the highest record in the world The efficieny of cell without textured surface was 16.6%, When adapting textured surface to the Cell, the efficiency has been improved over 12%.