• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.230-234
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• 2009

It is significant technique to increase competitiveness that solar cells have a high energy conversion efficiency and cost effectiveness. When making high efficiency crystalline Si solar cells, evaporated Ti/Pd/Ag contact system is widely used in order to reduce the electrical resistance of the contact fingers. However, the evaporation process is no applicable to mass production because high vacuum is needed. Furthermore, those metals are too expensive to be applied for terrestrial applications. Ni/Cu/Ag contact system of silicon solar cells offers a relatively inexpensive method of making electrical contact. Ni silicide formation is one of the indispensable techniques for Ni/Cu/Ag contact sytem. Ni was electroless plated on the front grid pattern, After Ni electroless plating, the cells were annealed by RTP(Rapid Thermal Process). Ni silicide(NiSi) has certain advantages over Ti silicide($TiSi_2$), lower temperature anneal, one step anneal, low resistivity, low silicon consumption, low film stress, absence of reaction between the annealing ambient. Ni/Cu/Ag metallization scheme is an important process in the direction of cost reduction for solar cells of high efficiency. In this article we shall report an investigation of rapid thermal silicidation of nickel on silngle crystalline silicon wafers in the annealing range of $350-390^{\circ}C$. The samples annealed at temperatures from 350 to $390^{\circ}C$ have been analyzed by SEM(Scanning Electron Microscopy).

• Journal of the Microelectronics and Packaging Society
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• v.11 no.2 s.31
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• pp.11-16
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• 2004

Electronic devices are getting smaller due to integration of electronic chip, and heat generated in electronic devices can cause loss of performance and/or reliability of the devices. In this research, metals such as gold, nickel and copper are plated onto a porous membrane by electroless plating method to make an efficient micro-heatsinks. Electroless plating includes sensitization and activation steps in pre-treatment steps. A polycarbonate(PC) membrane was sensitizied, activated and deposited in each metal solution for plating. Among manufactured microfibrils, heat transfer and radiation properties of Ni-microfibril with high surface area were more effective than those of $Au^-$ and Cu-microfibril.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.270-274
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• 2001

With Increasing importance of electroless nickel plating technology in many fields such as electronic and automobile industries, the treatment of the spent baths is becoming a serious problem. These spent baths contain iron and zinc as impurities, organic acids as complexing reagents, and phosphonate ions as oxidized species of tile reducing reagent. as well as several grams per liter of nickel. The spent baths are currently treated by conventional precipitation method. but a mettled with no sludge generation is desired. This work aims at establishing a recycling process of nickel from tile spent baths using solvent extraction. Extraction behaviors of nickel. iron. and zinc in various 쇼pes of real spent baths are investigated as a function of pH using LIX841, di (2-ethylhexyl)phosphoric acid (D2EHPA), and PC88A as tile extractants. Nickel is extracted by LIX84I at the equilibrium pH of more than 6 with high efficiency. For the weakly acid baths. iron and zinc are extracted by D2EHPA or PC88A without adjusting the pH of the baths leaving nickel in the aqueous phase. Stripping of nickel from LIX84I with sulfuric acid is also investigated. It is shown that concentrated nickel sulfate solution (> 100 ㎏-Ni/㎥) is obtained. This solution can be reused in the electroless plating process. Based on these findings, flow sheets for recovering nickel from the spent baths are proposed.

• 연구논문집
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• s.22
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• pp.151-160
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• 1992

The wear resistance of electroless Ni-P-X(X A1203, Diamond) composite coating layers was studied by Taber abrasion test technique. The wear resistance of composite coating layers was particularly relied upon the codeposited content, particle size and distribution of particles, and heat treatment of coating layers, as well as the electroless nickel plating bath employed. In this study, we lay emphasis on the wear resistance of electroless composite coating layers containing A1203 particles(1.2~Im, 6.7hIm, 11.5lIm, 20l1m) or diamond particles (1.5jim, 5gm). From the result of composite coating A1203 and diamond particles, the wear resistance of composite coating layers is as follows.

• Journal of Welding and Joining
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• v.35 no.3
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• pp.1-6
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• 2017

The effect of metal turnover (MTO) of electroless Ni plating bath on the brittle fracture behavior of electroless nickel electroless palladium immersion gold (ENEPIG)/Sn-3.0wt%Ag-0.5wt%Cu(SAC305) solder joint was evaluated in this study. The MTOs of the electroless Ni for the ENEPIG surface finish were 0 and 3. As the MTO increased, the interfacial IMC thickness increased. The brittle fracture behavior of the ENEPIG/SAC305 solder joint was evaluated with high speed shear (HSS) test. The HSS strength decreased with increasing the MTO of the electroless Ni bath. The brittle fracture increased with increasing the shear speed of the HSS test. The percentage of the brittle fracture for the 3 MTO sample was much higher than that for the 0 MTO sample.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.5
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• pp.361-370
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• 2009

Ni-PTFE composite plated on graphite (C/Ni-PTFE) and PTFE (PTFE/Ni-PTFE) particles were prepared uniformly by electroless composite plating. The conductivity of C/Ni-PTFE particles was 280 S/m higher than 95 S/m of PTFE/Ni-PTFE particles at same composite plating condition (Ni:35~36 wt%, PTFE:8 wt%). The C/Ni-PTFE particles were formed into the C/Ni-PTFE plate using heat treatment at $350^{\circ}C$ under 10~$1000\;kg/cm^2$. The C/Ni-PTFE plate showed 1) high conductivity of $5.7\;{\times}\;10^4\;S/m$ due to the existence of graphite as conducting aid and the formation of 3-dimensional Ni network 2) good gas diffusion caused by various pore volumes (0.01~$100\;{\mu}m$) in the plate. The plate could be useful for an electrode in an alkaline fuel cell (AFC). The current density of C/Ni-PTFE electrode indicated $84\;mA/cm^2$ at 0.3V and it was 3.0 times higher than that of PTFE/Ni-PTFE electrode.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.26-27
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• 1992

The effect of activation and electroless nickel plating conditions on contact properties were investigated for selective electroless nickel plating of Si farers in order to obtain an optimum condition of contact hole filling. According to RCA prosess, p-type si 1 icon (100) surface was cleaned out and activated. The effects of temperture, DMAB concentration, time, and stirring iwere investigated for activation of p-type Si(100) surface. The optimal activation condition obtained was 0.5M HF, 1mM PdCl$_2$, 2mM EDTA, 7$0^{\circ}C$, 90sec under ultrasonic vibration. In electroless nickel plating, the effect of temperature, DMAB concentration, pH, and plating ti me were studied. The optimal plating condition found was 0. 10M NiS0$_4$.$H_2O$, 0.lIM Citrate, pH 6.8, 6$0^{\circ}C$, 30 minutes. The contact resistence of fi]ms wascomparatively low. It took 30 minutes to obtain 1$\mu$m thick film with 8$\mu$M DMAB concentration. The film surface roughness was improved with increasing temperature and decreasing pH of the plating solution. The best quality of the film was obtained with the condition of temperature 6$0^{\circ}C$ and pH 6.8. The micro-victors hardness of film was about 600Hv and was decreased wi th increasing particle size of plating layer.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.210-216
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• 2016

In this paper, the electrical and resistance heating properties of carbon fiber heating elements with different electroless Ni-P plating times for car seat were studied. The specific resistance and specific heat of the carbon fibers were determined using 4-point probe method and differential scanning calorimetry (DSC), respectively. The surface morphology and temperature of carbon fibers were measured by scanning electron microscope (SEM) and thermo-graphic camera, respectively. From experimental results, the nickel layer thickness and surface temperature of carbon fibers increased with increasing the plating time. However, the specific heat and specific resistance decreased with respect to the increased plating time. In conclusion, the electroless Ni-P plating could improve the resistance heating and electrical properties of carbon fiber heating elements for car seat.

• Progress in Superconductivity and Cryogenics
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• v.23 no.3
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• pp.37-40
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• 2021

Nickel (Ni) is a kind of the rare earth resources. Since Ni-containing waste is drained after several plating operations in the factories, the effective recycling technique has been expected to be introduced. An actual magnetic separation technique using HTS bulk magnet generating the strong magnetic field has succeeded in collecting the paramagnetic slurry containing Ni-sulphate coarse crystals which were fabricated from the Ni-plating waste. The Ni compound in the collected slurry was identified as NiSO₄/6H₂O, showing slight differences in the particle size and magnetic susceptibility between the samples attracted and not-attract to the magnetic pole. This preferential extraction suggests us a novel recycling method of Ni resource because the compound is capable of recycling back to the plating processes as a raw material.

• Journal of Powder Materials
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• v.24 no.3
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• pp.242-247
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• 2017

In this study, the electroless nickel plating method has been investigated for the coating of Ni nanoparticles onto fine Al powder as promising energetic materials. The adsorption of nickel nanoparticles onto the surface of Al powders has been studied by varying various process parameters, namely, the amounts of reducing agent, complexing agent, and pH-controller. The size of nickel nanoparticles synthesized in the process has been optimized to approximately 200 nm and they have been adsorbed on the Al powder. TGA results clearly show that the temperature at which oxidation of Al mainly occurs is lowered as the amount of Ni nanoparticles on the Al surface increases. Furthermore, the Ni-plated Al powders prepared for all conditions show improved exothermic reaction due to the self-propagating high-temperature synthesis (SHS) between Ni and Al. Therefore, Al powders fully coated by Ni nanoparticles show the highest exothermic reactivity: this demonstrates the efficiency of Ni coating in improving the energetic properties of Al powders.