• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.445-449
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• 2018

Chromium plating is a common surface treatment technique extensively applied in industry due its excellent properties which include substantial hardness, abrasion resistance, corrosion resistance, surface color, and luster. In this study, the effect of $MoS_2$ particles of the composite coating was investigated. To improve the lubrication of mold, $Cr-P-C/MoS_2$ composite plating was studied by varying the $MoS_2$ content. The current efficiency of the composite plating incorporated $MoS_2$ particles was increased at $MoS_2$ contents of 0.5 and 1.0 g/l due to the incorporation of fine particles. On the other hand, when the content of $MoS_2$ is 1.0 g/l or more, the current efficiency is lowered due to an increase in impact on the cathode surface. In order to evaluate the mechanical properties of Scratch test were conducted. Scratch test confirmed the lubricity and abrasion resistance characteristics revealed that the composite plating with added $MoS_2$ had relatively low surface roughness and uniform surface modification to improve its properties.

• Journal of the Korean institute of surface engineering
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• v.25 no.3
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• pp.117-125
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• 1992

In the electrolysis process of zinc plating impurity ions must be removed from zinc chloride plating solution because it's harmful to the current efficiency and the purity of zinc plating. In this study using zinc ball as a prcipitant instead of zinc dust, the fundamental data for continuous cementation process was studied. Based upon two series of experiments that consist of batch experiment with cylindrical zinc specimen and continuous experiment with zinc balls, following results have been obtained. In the continuous experiment all impurity ions have been removed within 1 hour regardless of various experimental conditions.

• Corrosion Science and Technology
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• v.18 no.4
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• pp.148-153
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• 2019

Pure nickel with a thickness of 1 mm was plated on type 304 stainless steels and low alloy steels (JIS G3131 SPHC) by electrolytic plating method in a circulating plating bath. Plating performance, mechanical properties, and surface characteristics were evaluated in terms of pretreatment process, anode material, pH, current density, and flow rate of the plating solution. Addition of hydrochloric acid during pre-treatment process improved the adhesion performance of plating. To improve plating efficiency, it is desirable to use S-nickel rather than electrolytic nickel. The use of S-nickel was also confirmed to be desirable for maintaining the pH and concentration of the plated solution. The defect of the plating using S-nickel anode produced pit on the surface. However, it is believed that proper control can be obtained by increasing the flow rate. Internal stress and hardness values of electrolytic nickel plating according to current density need to be carried out with further studies.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.250-253
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• 2007

An evaporated Ti/Pd/Ag contact system is most widely used to make high-efficiency silicon solar cells, however, the system is not cost effective due to expensive materials and vacuum techniques. Commercial solar cells with screen-printed contacts formed by using Ag paste suffer from a low fill factor and a high shading loss because of high contact resistance and low aspect ratio. Low-cost Ni and Cu metal contacts have been formed by using electroless plating and electroplating techniques to replace the Ti/Pd/Ag and screen-printed Ag contacts. Ni/Cu alloy is plated on a silicon substrate by electro-deposition of the alloy from an acetate electrolyte solution, and nickel-silicide formation at the interface between the silicon and the nickel enhances stability and reduces the contact resistance. It was, therefore, found that nickel-silicide was suitable for high-efficiency solar cell applications. The Ni contact was formed on the front grid pattern by electroless plating followed by anneal ing at $380{\sim}400^{\circ}C$ for $15{\sim}30$ min at $N_{2}$ gas to allow formation of a nickel-silicide in a tube furnace or a rapid thermal processing(RTP) chamber because nickel is transformed to NiSi at $380{\sim}400^{\circ}C$. The Ni plating solution is composed of a mixture of $NiCl_{2}$ as a main nickel source. Cu was electroplated on the Ni layer by using a light induced plating method. The Cu electroplating solution was made up of a commercially available acid sulfate bath and additives to reduce the stress of the copper layer. The Ni/Cu contact was found to be well suited for high-efficiency solar cells and was successfully formed by using electroless plating and electroplating, which are more cost effective than vacuum evaporation. In this paper, we investigated low-cost Ni/Cu contact formation by electroless and electroplating for crystalline silicon solar cells.

• Aerospace Engineering and Technology
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• v.8 no.1
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• pp.138-143
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• 2009

Thermal barrier efficiency and endurance of coatings in liquid rocket engine combustor were evaluated for air plasma spray coating and electro/electroless plating. The result of firing tests has revealed occasional occurrence of local delamination of $ZrO_2$, NiCrAlY coating obtained by the method of air plasma spray in the region of supersonic flow and it necessitated a new coating method as a substitution. It was found that Ni-Cr coating by means of electro/electroless plating can substitute $ZrO_2$, NiCrAlY coatings of air plasma spray in terms of thermal barrier efficiency and endurance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.444-445
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• 2009

The metallic contact system of silicon solar cell must have several properties, such as low contact resistance, easy application and good adhesion. Ni is shown to be a suitable barrier to Cu diffusion as well as desirable contact metal to silicon. Nickel monosilicide(NiSi) has been suggested as a suitable silicide due to its lower resistivity, lower sintering temperature and lower layer stress than $TiSi_2$. Copper and Silver can be plated by electro & light-induced plating method. Light-induced plating makes use the photovoltaic effect of solar cell to deposit the metal on the front contact. The cell is immersed into the electrolytic plating bath and irradiated at the front side by light source, which leads to a current density in the front side grid. Electroless plated Ni/ Electro&light-induced plated Cu/ Light-induced plated Ag contact solar cells result in an energy conversion efficiency of 16.446 % on $0.2\sim0.6\;{\Omega}{\cdot}cm$, $20\;\times\;20\;mm^2$, CZ(Czochralski) wafer.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.686-686
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• 2013

Crystalline silicon solar cell is a semiconductor device that converts light into electrical energy. Screen printing is commonly used to form the front/back electrodes in silicon solar cell. Screen printing method is convenient but usually shows high resistance and low aspect ratio, which cause the efficiency decrease in crystalline silicon solar cell. Recently the plating method is applied in c-Si solar cell to reduce the resistance and improve the aspect ratio. In this paper, we investigated the effect of additional electroless Ag plating into screen-printed c-Si solar cell and compared their electrical properties. All wafers used in this experiment were textured, doped, and anti-reflection coated. The electrode formation was performed with screen-printing, followed by the firing step. Aften then we carried out electroless Ag plating by changing the plating time in the range of 20 sec~5 min and light intensity. The light I-V curve and optical microscope were measured with the completed solar cell. As a result, the conversion efficiency of solar cells was increased mainly due to the decreased series resistance.

• Journal of the Korean institute of surface engineering
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• v.10 no.2
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• pp.1-18
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• 1977

In decorative chromium plating, highly concentrated conventionl baths ($CrO_3$ 150~400g/l) have been used. Because of the problems of heavy metal pollution and the saving of raw materials, chromium plating from dilute bath has been developed recently. The present study was performed to determine the effects of all the variables in the low concentrated chromium plating bath, such as brightness, appearence, current efficiency, and plating rate with regard to the bath composition and plating conditions.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.37.1-37
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• 2001

Electric plating is used in various industry field. Specially, pulse plating is able to deposit material at high current density compared to conventional DC plating. For example, pulse plating can get more fine grain, can improve adhesion and metal distribution and current efficiency, can reduce internal stress and crack. Therefore, we developed bidirection pulse power supply(BPPS) which has high speed pulse current and high current density and improve deposition quality and increase plating speed in this paper. BPPS(Bidirection pulse power supply) needs high speed rising time, falling time and output current accuracy. BPPS consists of rectifier part, chopper part, invertor part, and control part. Rectifier part changes outprt current direction.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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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%.