• Journal of the Korean institute of surface engineering
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• v.24 no.4
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• pp.206-214
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• 1991

In the basic study of selective electroless Ni plating of Si wafers, plating rate and physical properties are investigated to obtain optimum conditions of contact hole filling. Si wafers are excellently activated in the concentration of 0.5M IF, 1mM PdCl2, 2mM EDTA at $70^{\circ}C$, 90sec. The optimum condition of Ni-B deposition on p-type Si wafers is 0.1M NiSO4, 0.11M Citrate, $70^{\circ}C$, pH6.8, 8mM DMAB. The main factor in the sheet resistences variation of films is amorphous and on heat treating matrix was transformed into a stable phase (Ni+Ni3B) at $300-400^{\circ}C$. But pH or DMAB concentration in the plating solution doesn't play role of heat-affected phase change.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.323-323
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• 2013

High power light-emitting diodes (LEDs) are widely used in many device applications due to its ability to operate at high power and produce high luminance. However, releasing the heat accumulated in the device during operating time is a serious problem that needs to be resolved to ensure high optical efficiency. Ceramic or Aluminium base metal printed circuit boards are generally used as integral parts of communication and power devices due to its outstanding thermal dissipation capabilities as heat sink or heat spreader. We investigated the characterisation of electroless plating of Ni-B film according to plating bath temperature, ranging from $50^{\circ}C$ to $75^{\circ}C$ on Ag paste/anodised Al ($Al_2O_3$)/Al substrate to be used in metal PCB for high power LED packing systems. X-ray diffraction (XRD), Field-Emission Scanning Electron Microscopy (FE-SEM) and X-ray Photoelectron Spectroscopy (XPS) were used in the film analysis. By XRD result, the structure of the as deposited Ni-B film was amorphous irrespective of bath temperature. The activation energy of electroless Ni-B plating was 59.78 kJ/mol at the temperature region of $50{\sim}75^{\circ}C$. In addition, the Ni-B film grew selectively on the patterned Ag paste surface.

• Corrosion Science and Technology
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• v.3 no.1
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• pp.26-29
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• 2004

Metal plated plastics are becoming more prevalent in materials of communication parts. A new technique MmSH is a process of injecting plastics to produce innovated physical properties compared to the conventional injection process. This study involves two ways of coating plastics Ni by electroless plating and varying bath and plasma treatment for improved adhesion strength between plating layer and surface. MmSH injection processed ASS with plasma treated after neutralization showed a superior adhesion force and a gloss and rate of deposition when it was in pH 7.5. On the other hand, conventional injection processed ASS was in pH 6.5.

• Transactions of Materials Processing
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• v.28 no.2
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• pp.77-82
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• 2019

Corrosion occurs well on surface of roll formed and Zn alloy subsequently electro-deposited on steel bolt under wet condition. In this study, variations in corrosion resistance were investigated through the measurement of polarization curves on steel bolts which were roll formed and subsequently coated with various types of coating methods. According to the measured polarization curve, Ni-P electroless deposits on roll formed steel increased the resistance to corrosion. The corrosion resistance of Zn alloy powder coated steel bolt was found to be better than that of Zn-Ni electro-deposited sample.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.137-137
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• 2013

본 연구에서는 반도체 검사 장비인 프로브 카드의 핵심 부품인 프로브 니들의 팁 부분의 내마모성을 향상시키기 위하여 무전해 Ni-B-W 합금 도금 실험을 실시하였다. 무전해 Ni-B-W 합금 도금 실험에서 여러 가지 제어인자 중 도금욕의 pH와 온도 그리고 환원제의 농도 등을 변수로 하였다. 도금욕 pH와 온도에 따른 전착속도 및 물성 변화를 관찰하였으며, 환원제 농도 변화에 의한 open circuit potential의 변화를 측정하였다.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.212-218
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• 2019

To investigate the effect of the oxyfluorination of carbon nanotubes (OF-CNTs) on electroless Ni deposition and electromagnetic interference shielding efficiency (EMI SE), CNTs were treated with a mixture of oxygen and fluorine gases and sequentially deposited with nickel. These samples were then manufactured into thin films on a polyimide film to evaluate their EMI SE. The surface chemical property of OF-CNTs was investigated by X-ray photoelectron spectroscopy. From the results of thermogravimetric and scanning electron microscopic analyses, it was found that both the amount of deposited Ni and the surface morphology changed depending on oxyfluorination. Moreover, the Ni-deposited CNTs pretreated with $O_2:F_2=1:9vol%$ exhibited the maximum EMI SE as approximately 19.4 dB at 1 GHz. These results were attributed to the formation of oxygen and fluorine functional groups on the surface of CNTs due to the oxyfluorination, and the functional groups enabled to deposit a suitable amount of Ni and improve the dispersion in the deposited solution.

• Korean Journal of Materials Research
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• v.15 no.11
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• pp.735-740
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• 2005

The phase transformation of Ni-B diffusion barrier by Cu diffusion was studied. The Ni-B diffusion barrier, thickness of 10(Inn, was electrolessly deposited on the electroplated Cu interconnect. The specimens were annealed either in Ar atmosphere or in $H_2$ atmosphere from $300^{\circ}C\;to\;800^{\circ}C$ for 30min, respectively. Although the Ni-B coated specimens showed the decomposition of $Ni_3B$ above $400^{\circ}C$ in both Ar atmosphere and $H_2$ atmosphere, Ni-B powders did not show the decomposition of $Ni_3B$. The $Ni_3B$ was decomposed to Ni and B in hi atmospherr: and the metallic Ni formed the solid solution with Cu and the free B was oxidized to $B_2O_3$. However, both the boron hydride and free B were not observed in the diffusion barrier after the annealing in $H_2$ atmos There. These results revealed that the decomposition of $Ni_3B$ by Cu made the Cu diffusion continued toward the Ni-B diffusion barrier.