• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1740-1745
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• 2004

A simplified resistor network model for electrical and mass transport in anode-supported planar solid oxide fuel cell (SOFC) was constructed in order to investigate the effect of interconnect rib geometry on the cell performance. For accurate potential calculation, activation and concentration over-potentials at the electrode/electrolyte interfaces were fully considered in this calculation. When contact resistance was not considered, the optimum interconnect rib length were calculated to be $0.1{\sim}0.2$ mm for 2 mm half unit cell for given operation conditions and properties. However, with realistic contact resistance, the interconnect rib length should be increased to provide larger contact area and thus to obtain better performance.

• 한국의류학회지
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• 제45권1호
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• pp.168-179
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• 2021

This study presents and develops a textile type touch sensor structural design that is easy to implement. First, the design of the touch sensor circuit finds the size of the switch with the easiest finger contact and selects a structure with a long circuit with the lowest resistance value. An experiment is performed on a change in an electrostatic capacitance value that accompanies the distance on the electrode and the magnitude of the electrode area of the structure; however, the structure having the distance on the electrode and the large electrode area shows the best resistance change. The laundry assessment was conducted three times at a time and ten times at a time with an average standard deviation less than one ohm, with little change in resistance. Consequently, there were no problems with durability and performance for laundry. Finally, in the bending evaluation, the difference in resistance can be seen between 1-2 ohms and was developed as a smart wearable in the future; in addition, there was no problem as a difference in resistance can be seen between 1 and 2 ohms.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.833-834
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• 2013

• 한국재료학회지
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• 제29권4호
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• pp.228-232
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• 2019

Copper electroplating and electrode patterning using a screen printer are applied instead of lithography for heterostructure with intrinsic thin layer(HIT) silicon solar cells. Samples are patterned on an indium tin oxide(ITO) layer using polymer resist printing. After polymer resist patterning, a Ni seed layer is deposited by sputtering. A Cu electrode is electroplated in a Cu bath consisting of $Cu_2SO_4$ and $H_2SO_4$ at a current density of $10mA/cm^2$. Copper electroplating electrodes using a screen printer are successfully implemented to a line width of about $80{\mu}m$. The contact resistance of the copper electrode is $0.89m{\Omega}{\cdot}cm^2$, measured using the transmission line method(TLM), and the sheet resistance of the copper electrode and ITO are $1{\Omega}/{\square}$ and $40{\Omega}/{\square}$, respectively. In this paper, a screen printer is used to form a solar cell electrode pattern, and a copper electrode is formed by electroplating instead of using a silver electrode to fabricate an efficient solar cell electrode at low cost.

• Journal of Welding and Joining
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• 제7권2호
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• pp.60-69
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• 1989

The present study was aimed at investigating the effect of welding parameters such as welding current, electrode force(or squeeze force) and parts cleaning on the sound weld, and establishing the most reliable weld conditions for HWP(Heavy Water Reactor) fuel end capping with the resistance upset butt welding. Major results obtained are as follows. 1. The amount of sound weld was increased with increasing weld current(5.0-11KA) because the activated diffusion with increasing heat generation played an important role in eliminating the porosity and weld line in the weld interface. 2. It was found that weld current was not significantly influenced by the electrode force although the increase of it caused a slight increase of weld current and upset deformation. 3. Acetone rinsing before drying for the Zircaloy-4 end cap cleaning produced the reliable sound weld because it would remove the remaining solvent and surface films, and provided the uniform contact between the end cap and the tube. 4. The optimum welding conditions for fuel end capping by a resistance upset hytt welding are obtained as follows. weld current: 10-11KA, electrode force: 62-90KPa parts cleaning: vapor degreasing.rarw.water, acetone rinsing.rarw.drying.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.94.2-94.2
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• 2007

• 한국전기전자재료학회논문지
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• 제29권6호
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• pp.370-375
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• 2016

In this paper, we investigated the electrical properties of crystalline silicon solar cell fabricated with Ni/Cu/Ag plating. The laser process was used to ablate silicon nitride layer as well as to form the selective emitter. Phosphoric acid layer was spin-coated to prevent damage caused by laser and formed selective emitter during laser process. As a result, the contact resistance was decreased by lower sheet resistance in electrode region. Low sheet resistance was obtained by increasing laser current, but efficiency and open circuit voltage were decreased by damage on the wafer surface. KOH treatment was used to remove the laser damage on the silicon surface prior to metalization of the front electrode by Ni/Cu/Ag plating. Ni and Cu were plated for each 4 minutes and 16 minutes and very thin layer of Ag with $1{\mu}m$ thickness was plated onto Ni/Cu electrode for 30 seconds to prevent oxidation of the electrode. The silicon solar cells with KOH treatment showed the 0.2% improved efficiency compared to those without treatment.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.5.1-5.1
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• 2009

Organic photovoltaic (OPV)cells have attracted considerable attention due to their potential for flexible, lightweight, and low-cost application of solar energy conversion. Since a 1% power conversion efficiency (PCE) OPV based on a single donor-acceptor heterojunction was reported by Tang, the PCE has steadily improved around 5%. It is well known that a high parallel (shunt)resistance and a low series resistance are required simultaneously to achieve ideal photovoltaic devices. The device should be free of leakage current through the device to maximize the parallel resistance. The series resistance is attributed to the ohmic loss in the whole device, which includes the bulk resistance and the contact resistance. The bulk resistance originated from the bulk resistance of the organic layer and the electrodes; the contact resistance comes from the interface between the electrodes and the active layer. Furthermore, it has been reported that the bulk resistance of the indium tin oxide (ITO) of the devices dominates the series resistance of OPVs for a large area more than $0.01\;cm^2$. Therefore, in practical application, the large area of ITO may significantly reduce the device performance. In this work, we investigated the effect of sheet resistance ($R_{sh}$) of deposited ITO on the performance of OPVs. It was found that the device performance of polythiophene-fullerene (P3HT:PCBM) bulk heterojunction OPVs was critically dependent on Rsh of the ITO electrode. With decreasing $R_{sh}$ of the ITO from 39 to $8.5\;{\Omega}/{\square}$, the fill factor (FF) of OPVs was dramatically improved from 0.407 to 0.580, resulting in improvement of PCE from $1.63{\pm}0.2$ to $2.5{\pm}0.1%$ underan AM1.5 simulated solar intensity of $100\;mW/cm^2$.

• 플랜트 저널
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• 제16권3호
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• pp.47-52
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• 2020

본 연구에서는 알루미늄으로 제작된 심해 장비의 부식 저항 능력 향상시키기 위해 알루미늄 부식 방지 방법과 측정방법을 조사하였다. 조사된 부식 방지 방법은 Cathodic Protection(음극화 보호), Conversion Coating, Anodizing, 및 Organic Coating이었다. 그리고 간단하게 조사된 측정 방법은 Scanning Electron Microscope (SEM), Electrochemical Impedance Spectroscopy (EIS), Glow discharge optical emission spectrum spectroscopy (GD-OES), Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), Scanning Vibrating Electrode Technique (SVET), Contact Angle(접촉각), Interfacial Tension (경계면 장력)이었다. 알루미늄 부식을 방지하기 위해 널리 사용되는 방법은 Anodizing과 Organic Coating이었으며, 부식 측정을 위해서는 여러 방법들이 골고루 사용되었다. 그 중 많이 사용되는 방법은 표면의 구조를 관찰하 위한 SEM과 부식 저항 능력을 측정하기 위한 접촉각 측정이었다.

• 한국전기전자재료학회논문지
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• 제26권12호
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• pp.858-862
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• 2013

The front electrode should be used to make solar cell panel so as to collect electron. The front electrode is used by paste type, printed on the Si-solar cell wafer and sintered at about $800^{\circ}C$. The paste is composed Ag powder and glass frit which make the ohmic contact between Ag electrode and n-type semiconductor layer. From the previous study, the Ag electrodes which used two commercial glass frit of Bi-system were so different on the interface resistance. The main composition of them was Bi-Zn-B-Si-O and few additives added in one of them. In this study, glass frit was made with the ratio of $Bi_2O_3$ and ZnO on the main composition, and then paste using glass frit was prepared respectively. And, also, the paste using the glass frit added oxide additives were prepared. The change of interface resistance was not large with the ratio of $Bi_2O_3$ and ZnO. In the case of G6 glass frit, 78 wt% $Bi_2O_3$ addition, the interface resistance was $190{\Omega}$ and most low. In the glass frit added oxide, the case of Ca increased over 10 times than it of G6 glass frit on the interface resistance. It was thaught that after sintering, Ca added glass frit was not flowed to the interface between Ag electrode and wafer but was in the Ag electrode.