• Korean Journal of Materials Research
• /
• v.5 no.7
• /
• pp.794-801
• /
• 1995

To connect the driver IC and Al coated glass, a method has been developed to plate electrolessly Ni on Al/PR system. It Is necessary to pretreat Al to remove oxide film before plating. In order to find pretreatment process which does not damage photoresist or glass, alkaline and fluoride zincate process have been investigated. Because photoresist and aluminum thin film can easily dissolve in alkaline solution, it is considered that the fluoride zincate process was a suitable one. After immersion in the zincate solution containing 1.5 g/$\ell$ ammonium bifluoride and 100 g/$\ell$ zinc sulfate, electroless nickel plating could be performed. The additive in the zincate solution and thiourea in the plating solution increased smoothness of the plated surface. Acld dip could improve the uniformit of the surface.

• Korean Journal of Materials Research
• /
• v.10 no.12
• /
• pp.853-863
• /
• 2000

In this study, a new UBM materials system for solder flip chip interconnection of Cu pads were investigated using electroless copper (E-Cu) and electroless nickel (E-Ni) plating method. The interfacial reaction between several UBM structures and Sn-36Pb-2Ag solder and its effect on solder bump joint mechanical reliability were investigated to optimife the UBM materials design for solder bump on Cu pads. Fer the E-Cu UBM, continuous coarse scallop-like $Cu_{6}$ $Sn_{5}$ , intermetallic compound (IMC) was formed at the solder/E-Cu interface, and bump fracture occurred this interface under relative small load. In contrast, Fer the E-Ni/E-Cu UBM, it was observed that E-Ni effectively limited the growth of IMC at the interface, and the Polygonal $Ni_3$$Sn_4$ IMC was formed because of crystallographic mismatch between monoclinic $Ni_3$$Sn_4$ and amorphous E-Ni phase. Consequently, relatively higher bump adhesion strength was observed at E-Ni/E-Cu UBM than E-Cu UBM. As a result, it was fecund that E-Ni/E-Cu UBM material system was a better choice for solder flip chip interconnection on CU PadS.

• Proceedings of the KAIS Fall Conference
• /
• 2002.11a
• /
• pp.243-245
• /
• 2002

ABS(Acrylonitrile Butadiene Styrene) 수지는 낮은 비중과 전기전도도, 가공성 등 우수한 물리적 성질을 갖는다. ABS 수지 제조방법인 Conventional process와 이를 개선한 MmSH(Momentary mold Surface Heating) injection process로 제조하여 나타나는 도금의 최적 조건을 연구하였다. 탈지, 에칭, Neutralization, Catalyzing, Accelerating의 전처리 과정을 거쳐 pH 변화에 따른 무전해 Ni 도금을 실시한 결과 각 수지 모두 pH7 이상에서 도금속도와 밀착력이 증가하였으나 MmSH injection process로 제작된 ABS 수지보다 Coventional process에서 제작된 ABS 수지의 밀착력이 우수한 경향이 나타났다.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2011.05a
• /
• pp.113-113
• /
• 2011

알루미늄 박막 커패시터 제작을 위해 선택적인 알루미늄 etching과 anodizing을 이용한 유전체($Al_2O_3$) 형성, 전극층 형성을 위한 무전해 Ni-P 도금을 진행하였다. $5{\mu}m$ patterns/$10{\mu}m$ space를 가지는 dot patterns을 알루미늄 기판에 patterning하고, 이를 각각의 전류밀도 조건에서 etching한 후, barrier type anodizing을 진행하였다. 유전체에 전극층은 무전해 Ni-P 도금을 통해 형성하였으며, 이렇게 제작된 알루미늄 박막 커패시터 특성을 평가하였다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2005.10a
• /
• pp.273-276
• /
• 2005

Packing characteristics of amorphous alloy particles were investigated by scanning electron microscopy, compositional analysis, micro-hardness test and finite element method (FEM). Electroless Ni-plating was made on the surface of the Cu-based amorphous particles before consolidation in ambient atmosphere at an intermediate region of glass transition and crystallization temperatures $(T_g\;and\;T_x)$. Some parts of the Ni-layer in the interfaces of the consolidated particles disappeared, while some of them still remained without appreciable change in compositions. No cracks or fractures were found in the particles, which may occur at low temperatures below or near $T_g$ as anticipated by the FEM analysis. Crystallization and change in hardness were not observed after consolidation.

• Carbon letters
• /
• v.9 no.2
• /
• pp.105-107
• /
• 2008

In this work, we employed an electroless nickel plating on glass fibers in order to enhance the electric conductivity of fibers. And the effects of metal content and plating time on the conductivity of fibers were investigated. From the results, island-like metal clusters were found on the fiber surfaces in initial plating state, and perfect metallic layers were observed after 10 min of plating time. The thickness of metallic layers on fiber surfaces was proportion to plating time, and the electric conductivity showed similar trends. The nickel cluster sizes on fibers decreased with increasing plating time, indicating that surface energetics of the fibers could become more homogeneous and make well-packed metallic layers, resulting in the high conductivity of Ni/glass fibers.

• Progress in Superconductivity
• /
• v.6 no.2
• /
• pp.133-137
• /
• 2005

We fabricated the Au/Ni template for YBCO coated conductors and evaluated texture formation and the microstructural evolution. The cube textured Ni substrate was fabricated by rolling and recrystallization annealing, and subsequently Au layer formed on the substrate by electroless-plating method. The texture was evaluated by pole-figure with x-ray goniometer with orientation distribution function (ODF) analysis. The surface roughness and grain boundary morphology of template were characterized by atomic force microscopy (AFM) We observed that Au layer deposited epitaxially on Ni substrate and formed a strong cube texture when plating time was optimized. The full-width at half-maximum (FWHM) was $8.4^{\circ}$ for out-of-plane and $9.98^{\circ}$ for in-plane texture for plating time of 30 min. Microstructural observation showed that the Au layer was homogeneous and dense without formation of crack/microcrack. In addition, we observed that root-mean-square (RMS) and depth of grain boundary were 14.6 nm and 160 $\AA$ for the Au layer, respectively, while those were 27.0 nm and 800 $\AA$ for the Ni substrate, indicating that the electoless-plated Au layer had relatively smooth surface and effectively mollified grain groove.

• Journal of the Korean institute of surface engineering
• /
• v.50 no.5
• /
• pp.373-379
• /
• 2017

Dry processes like evaporation and sputtering in vacuum chamber are difficult to make a uniform, large area and high quality film on thin PET substrate because of PET degradation and bad adhesion. On the other hand, wet processes like electro or electroless plating have complex processes and require high environmental cost. In this study, we successfully prepared $2{\mu}m$ Zn/Cu/Ni multilayers coated on $12{\mu}m$ polyethylene terephthalate (PET) substrate by using dry-wet mixing processes. Their surface electric resistances were evaluated around $0.2{\Omega}$ by using 4 probe measurements. Furthermore, their corrosion resistance also evaluated by natural potential test and compared with other wet, dry and mixing process samples.

• Journal of Electrochemical Science and Technology
• /
• v.11 no.2
• /
• pp.155-164
• /
• 2020

Here we report our preliminary results about nickel phosphide (Ni-P) electroless coating on the surface of cellulose paper (CP) and its feasibility as the anode for lithium (Li) batteries. In particular, CP can act as a flexible skeleton to maintain the mechanical structure, and the Ni-P film can play the roles of both the anode substrate and the active material in Li batteries. Ni-P films with different P contents were plated uniformly and compactly on the microfiber strands of CP. When they were tested as the anode for Li battery, their theoretical capacity per physical area was comparable to or higher than hypothetical pure graphite and P film electrodes having the same thickness. After the large irreversible capacity loss in the first charge/discharge process, the samples showed relatively reversible charge/discharge characteristics. All samples showed no separation of the plating layer and no detectable micro-cracks after cycling. When the charge cut-off voltage was adjusted, their capacity retention could be improved significantly. The electrochemical result was just about the same before and after mechanical bending with respect to the overall shape of voltage curve and capacity.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.347.1-347.1
• /
• 2016

Screen printing is commonly used to form the electrode for crystalline silicon solar cells. However, it has caused high resistance and low aspect ratio, resulting in decrease of conversion efficiency. Accordingly, Ni/Cu/Ag plating method could be applied for crystalline silicon solar cells to reduce contact resistance. For Ni/Cu/Ag plating, laser ablation process is required to remove anti-reflection layers prior to the plating process, but laser ablation results in surface damage and then decrease of open-circuit voltage and cell efficiency. Another issue with plating process is ghost plating. Ghost plating occurred in the non-metallized region, resulting from pin-hole in anti-reflection layer. In this paper, we investigated the effect of Ni/Cu/Ag plating on the electrical properties, compared to screen printing method. In addition, phosphoric acid layer was spin-coated prior to laser ablation to minimize emitter damage by the laser. Phosphorous elements in phosphoric acid generated selective emitter throughout emitter layer during laser process. Then, KOH treatment was applied to remove surface damage by laser. At this step, amorphous silicon formed by laser ablation was recrystallized during firing process and remaining of amorphous silicon was removed by KOH treatment. As a result, electrical properties as Jsc, FF and efficiency were improved, but Voc was lower than screen printed solar cells because Voc was decreased due to surface damage by laser process. Accordingly, we expect that efficiency of solar cells could be improved by optimization of the process to remove surface damage.