비시안 무전해 Au 도금의 석출거동에 미치는 하지층 무전해 Ni-P 도금 조건의 영향

김동현,한재호,Kim, DongHyun,Han, Jaeho 한국표면공학회 2022 한국표면공학회지 Vol.55 No.5

Gold plating is used as a coating of connector in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. In most cases, internal connection between device and package and external terminals for connecting packaging and printed circuit board are electroless Ni-P plating followed by immersion Au plating (ENIG) to ensure connection reliability. The deposition behavior and film properties of electroless Au plating are affected by P content, grain size and mixed impurity components in the electroless Ni-P alloy film used as the underlayer plating. In this study, the correlation between electroless nickel plating used as a underlayer layer and cyanide-free electroless Au plating using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent was investigated.

교정용 선재의 직경 증가를 위한 전기도금법과 무전해도금법의 비교연구

김재남,조진형,성영은,이기헌,황현식 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.2

본 연구는 교정용 선재의 직경을 증가시키기 위한 방법으로 무전해도금법의 이용 가능성 여부를 전기도금법과의 비교를 통해 알아보고자 시행되었다. 0.016 인치 스테인레스 스틸 교정용 선재에 도금을 위한 전처리를 시행한 후, 시중에 판매되는 무전해니켈도금액(Hessonic-Gr, 신풍금속, 한국)을 사용하여 90℃ 온도에서 0.018 인치 직경이 될 때까지 도금을 시행하였다. 무전해도금 과정 중 시간에 따른 직경증가율을 구하는 한편, 도금 후 세 지점의 직경을 계측하여 균일성을 평가하였다. 도금 금속의 정성분석을 위하여 X-선 회절분석을 시행하는 한편, 물성검사를 시행한 후 전기도금한 경우와 각각 비교 분석하였다. 연구결과 무전해도금한 군이 전기도금을 시행한 군보다 강성, 항복강도, 극한강도 모두 높은 경향을 보였으며 강성과 극한강도에서 통계적으로 유의한 차이를 나타내었다 (p < 0.05). 또한 무전해도금한 군의 직경증가율은 0.00461 ± 0.00003mm/5min (0.00092mm/min)로, 전기도금한 군의 직경증가율 0.00821 ± 0.00015mm/min와 차이를 보였다. 도금 후 세 지점의 직경을 계측하여 균일성을 평가한 결과, 두가지 도금법 모두에서 균일한 양상을 보였다. 이상의 결과로 무전해도금법을 통해 직경이 증가된 선재가 전기도금법에 의해 직경이 증가된 선재보다 기존의 선재와 가까운 물성을 보임을 알 수 있었으며, 이의 임상적 적용을 위해서는 도금시간의 감소가 필요함을 알 수 있었다. The purpose of this study was to evaluate electroless plating as a method of increasing the diameter of an orthodontic wire in comparison with eletroplating. After pretreatment plating of the 0.016 inch stainless steel orthodontic wire, electroless plating was performed at 90℃ until the diameter of the wire was increased to 0.018 inch. During the process of electroless plating, the diameter of the wire was measured every 5 minutes to examine the increasing ratio of the wire's diameter per time unit. And to examine the uniformity, the diameter at 3 points on the electroless-plated orthodontic wire was measured. An X-ray diffraction test for analyzing the nature of the plated metal and a 3-point bending test for analyzing the physical property were performed. The electroless-plated wire group showed a increased tendency for stiffness, yield strength, and ultimate strength than the electroplated wire group. And there was a statistically significant difference between the two groups for stiffness and ultimate strength. In the electroless-plated wire group, the increasing ratio of the diameter was 0.00461 ± 0.00003 mm/5 min (0.00092 mm/min). In the electroplated wire group, ti was 0.00821 ± 0.00015 mm/min. The results of the uniformity test showed a tendency for uniformity in both the plating methods. The results of this study suggest that electroless plating of the wire is closer to the ready-made wire than electroplating wire in terms of the physical property. However, the length of plating time needs further consideration for the clinical application of electroless plating.

The effect of bath conditions on the electroless nickel plating on the porous carbon substrate

So-Young Cheon,So-Yeon Park,Young-Mok Rhym,Doo-Hyun Kim,Jae-Ho Lee 한국물리학회 2011 Current Applied Physics Vol.11 No.3

Electroless nickel plating is widely used technique in industries. In most cases, electroless nickel plating was applied on the open surfaces and the rate of deposition was controlled with temperature and time. However, when the electroless plating is applied on the porous carbon, the rate of deposition is also dependent on the activation process. In this research, electroless nickel plating on the porous carbon was investigated. The porous carbon was selected as the substrate. The pore sizes of carbon substrates were 16―20 mm and over 20 mm. Since hydrophobic surface prevented the penetration of solution into porous carbon, the carbon surface changed from hydrophobic to hydrophilic after immersing the substrate in an ammonia solution at 60 ℃. The alkaline bath and acidic bath were used in electroless nickel plating. The pHs were 9―11 in alkaline bath and 4―5 in acidic bath. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As increasing pH in each bath conditions, the content of phosphorous in nickel deposit was decreased. The rate of electroless plating in alkaline bath was faster than that in acidic bath. The minimum concentration of PdCl_2 for the electroless nickel plating was 10 ppm in acidic bath and 5 ppm in alkaline bath. The thickness of nickel was not significantly affected by the concentration PdCl_2.

Application of electroless plating process for multiscale Ni-La_0.8Sr_0.2Ga_0.8Mg_0.2O_3-σ SOFC anode fabrication

Kang, Juhyun,Lee, Kunho,Yoo, Jae Young,Bae, Joongmyeon Elsevier 2018 International journal of hydrogen energy Vol.43 No.12

<P><B>Abstract</B></P> <P>An electroless plating process of nickel is introduced to solve the drawbacks of impregnation for developing the multiscale anode of a solid oxide fuel cell (SOFC). Impregnation is the conventional fabrication method of the electrode. The process is not favorable for depositing nanoscale metal catalysts due to severe problems including agglomeration of the catalysts while reducing metal oxides. Thus, as an alternative, we propose electroless plating of nickel to fabricate a multiscale nickel-based SOFC anode. A Ni-LSGM (La<SUB>0.8</SUB>Sr<SUB>0.2</SUB>Ga<SUB>0.8</SUB>Mg<SUB>0.2</SUB>O<SUB>3-σ</SUB>) anode is selected. The low chemical compatibility of LSGM with nickel emphasizes the advantage of the electroless plating process. First, nanoscale nickel particles are successfully applied as the main catalyst of the SOFC anode by plating nickel to the surface of the LSGM scaffold substrate near the triple phase boundary region. Thin film X-ray diffraction and image analysis confirm that pure nanoscale nickel particles form on the entire substrate, even at a low temperature (60 °C) without secondary phase formation. Electrochemical impedance spectroscopy analysis is then performed to verify the possibility of implementing an efficient Ni-LSGM anode through nickel electroless plating. As a result, the new Ni-LSGM anode shows ∼50 times higher electrochemical performance than that of an impregnated Ni-LSGM anode.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel electroless plating process was introduced to replace impregnation. </LI> <LI> Pure crystalline nickel was plated on a microporous LSGM scaffold structure. </LI> <LI> Electroless plated anode shows ∼50 times higher performance than an impregnated anode. </LI> </UL> </P>

Dendrite 형상 구리 입자의 무전해 은 도금에 의한 열적 안정성 향상에 관한 연구

황인성 ( In-seong Hwang ),남광현 ( Kwang Hyun Nam ),정대원 ( Dae-won Chung ) 한국공업화학회 2022 공업화학 Vol.33 No.6

Dendrite 형태의 구리 입자 표면을 은으로 무전해 도금을 하는 과정에서, 치환도금(displacement plating)과 화학 환원도금(reducing electroless plating)을 병용하여 다양한 silver-coated copper (Ag@Cu) 입자들을 제조하였다. Ag@Cu 입자들의 물리화학적 특성은 SEM-EDS, TGA, XPS, XRD 및 BET 등으로 분석하였으며, 환원반응에 의하여 코팅되는 은은 구리 입자 표면에 나노 입자 형태로 형성되는 것을 확인할 수 있었다. Ag@Cu 입자들을 에폭시 수지와 복합화하여 도전성 필름을 제조하고 그의 열적 안정성을 평가하였다. 치환 반응과 환원 반응의 차이가 Ag@Cu 필름의 초기 저항 및 열적 안정성에 미치는 영향에 관하여 연구하였다. While in the process of electroless plating of dendrite-shape copper with silver, various silver-coated copper (Ag@Cu) particles were prepared by using both displacement plating and reducing electroless plating. The physicochemical properties of Ag@Cu particles were analyzed by scanning electron microscope- energy-dispersive X-ray spectroscopy (SEM-EDS), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Brunauer-Emmett-Teller analysis (BET), and it was confirmed that the silver coated by the reducing electroless plating was formed as nano-particles on the copper surface. Ag@Cu particles were compounded with an epoxy resin to prepare a conductive film, and its thermal stability was evaluated. We investigated the effect of the difference between the displacement plating and reducing electroless plating on the initial resistance and thermal stability of conductive films.

무전해 니켈/금도금 기술 개발에 관한 연구

박수길,박종은,정승준,엄재석,전세호,이주성,Park Soo-Gil,Park Jong-Eun,Jung Seung-Jun,Yum Jae-Suk,Jun Sae-ho,Lee Ju-Seong 한국전기화학회 1999 한국전기화학회지 Vol.2 No.3

최근 large scale integrated circuits(LSI) 및 printed circuit board(PCB)의 세밀화가 전자기기의 소형화로 인하여 필수 불가결하게 되었다. 전해 도금은 LSI및 PCB의 전도도 및 부식저항을 향상시키기 위해서 전도성 라인의 말단에 적용되고 있다. 그러나 회로 기판의 소형화 및 고직접화로 인하여 적용되지 못하고 있다. 따라서 최근 무전해 도금은 복잡한 장치와 외부에서 전원을 필요치 않는 작동의 간편함 때문에 매우 각광 받고 있는 방법 중의 하나이다. 본 연구는 무전해 니켈/금도금의 도금 기술 개발을 위해 시험하였다. 무전해 니켈 도금은 $85^{\circ}C$의 도금 욕에서 PCB기판 위에 침적 시켰고 그 다음 금층은 동일한 방법으로 $90^{\circ}C$에서 니켈 층위에 침적 시켰다. Bonderbility는 무전해 니켈/금도금의 안정성을 평가하기 위해 gold wire 또는 solder ball 테스트로 실험하였다. Recently, miniaturization of large scale integrated circuits (LSI) and printed circuit board (PCB) have become essential with the downsizing of electronic devices. Gold electroplating is applied of conductivity wiring or terminals for improvement of conductivity and corrosion resistance. However, electroplating is not applicable since the circuits are becoming finer and denser. Accordingly, electroless plating is recently highly attractive method because of the simplicity of the operation requiring no external source of current and no elaborate equipment. In this work, we tried to develop a plating technique on electroless Ni/Au plating. First, the electroless Ni plating was deposited on the PCB with agitation in the bath at $85^{\circ}C$. Then the Au layer was deposited on the Ni layer surface by same method at $90^{\circ}C$. The bonderability were tested in order to evaluate the stability of the electroless Ni/Au by gold wire or solder ball test.

Electroless Pd deposition on a planar porous stainless steel substrate using newly developed plating rig and agitating water bath

서범석,한재윤,이관영,김동원,이신근 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.1

A new plating bath was developed to prevent palladium plating in the pores of the porous stainless steel support when using plate-type porous substrate. The plating bath, composed of a holder, a rubber O-ring and a bottom, provides very simple assembly and is very effective in preventing palladium plating in the pores of porous stainless steel. The agitation of the plating solution increases plating rate significantly because the agitation improves the external mass transfer of Pd ion and reducing agent to the membrane surface facilitating ~99.7% plating yield of palladium ion. This new plating method carried out at a temperature range of 293 to 298 K provides a very simple and economic membrane manufacturing process. Using a newly developed plating rig, an 88.9-mm diameter membrane was fabricated, and gas permeation tests showed that the hydrogen permeation flux reached ~0.9mol s−1 m−2 at 873 K and a pressure difference of 300 kPa and selectivity (H2/N2) was ~1,850 at 873 K with a pressure difference of 100 kPa.

Effect of CuO introduced on activated carbon fibers formed by electroless plating on the NO gas sensing

Kim, Min-Ji,Lee, Sangmin,Lee, Kyeong Min,Jo, Hanjoo,Choi, Suk Soon,Lee, Young-Seak Elsevier 2018 Journal of industrial and engineering chemistry Vol.60 No.-

<P><B>Abstract</B></P> <P>High-performance gas sensors were fabricated from activated carbon fibers (ACFs) introduced with CuO. The electroless CuO plating of ACFs was carried out to investigate the nitric oxide (NO) gas sensing ability with respect the plating time. The gas sensors were fabricated by dropping a solution (CuO-introduced ACFs+DMF) onto SiO<SUB>2</SUB>/Si wafers patterned with Pt electrodes. The NO gas sensing behavior of the ACF-based gas sensors was determined by resistance measurements. As the plating time increased, the CuO content on the ACF surface increased, and the specific surface area of the ACFs decreased. The gas sensor fabricated from untreated ACFs showed a 4% resistance change upon exposure to NO gas, whereas the sensor with CuO-introduced ACFs showed an approximately 12.5% resistance change. This phenomenon is attributed to the increased number of hole carriers in the ACFs due to CuO, which promotes electron transfer, and benefits the effective detection of NO gas. This method provides as a unique surface treatment strategy to improve the NO gas sensing efficiency.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CuO particles were introduced on ACFs surface via electroless copper plating. </LI> <LI> The CuO-ACF electrodes were used as NO gas sensors. </LI> <LI> When the plating time is 15min, NO gas sensing and recovery were improved than untreated ACFs. </LI> <LI> The introduced CuO acts as a catalyst on ACFs surface to transfer electrons. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>To improve the sensitivity of NO gas, ACFs were treated according plating time conditions and used as a NO gas sensor material.</P> <P>[DISPLAY OMISSION]</P>

Preparation of Pt Films on GaAs by 2-step Electroless Plating

Hungsu Im,Yong Jun Seo,Young Joo Kim,Kai Wang,Sang Sik Byeon,Bon Heun Koo,Ji Ho Chang 한국표면공학회 2009 한국표면공학회지 Vol.42 No.4

Electroless plating is influenced by kinds of parameters including concentrations of electrolyte, plating time, temperature and so on. In this study, the Pt thin films were prepared on GaAs substrate by a 2-step electroless plating depending method. The small Pt catalytic particles by using Pt I bath exhibited islands-morphology dispersed throughout the substrate surface at 65℃, as function as a sensitized thin film, and then a thicker Pt film grew upon the sensitized layer by the second Pt Ⅱ bath. As the growth of Pt film is strongly influenced by the plating time and temperature, the plating time of Pt Ⅱ bath varied from 5 min to 40 min at 60~80℃ after Pt I bath at 60~80℃ for 5 min. It is found that the film grows with the increasing plating time and temperature. The resistivity value of Pt deposited layer was characterized to study the growth mechanism of 2-step plating.

Novel Environmentally Benign and Low-Cost Pd-free Electroless Plating Method Using Ag Nanosol as an Activator

Kim, Jun Hong,Oh, Joo Young,Song, Shin Ae,Kim, Kiyoung,Lim, Sung Nam The Korean Electrochemical Society 2017 Journal of electrochemical science and technology Vol.8 No.3

The electroless plating process largely consists of substrate cleaning, seed formation (activator formation), and electroless plating. The most widely used activator in the seed formation step is Pd, and Sn ions are used to facilitate the formation of this Pd seed layer. This is problematic because the Sn ions interfere with the reduction of Cu ions during electroless plating; thus, the Sn ions must be removed by a hydrochloric acid cleaning process. This method is also expensive due to the use of Pd. In this study, Cu electroless plating was performed by forming a seed layer using a silver nanosol instead of Pd and Sn. The effects of the Ag nanosol concentration in the pretreatment solution and the pretreatment time on the thickness and surface morphology of the Cu layer were investigated. The degrees of adhesion to the substrate were similar for the electroless-plated Cu layers formed by conventional Pd activation and those formed by the Ag nanosol.