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A preparation method of electroless copper electrodes based on elastic nylon fabric for ECG monitoring is proposed to meet the key needs of monitoring accuracy and wearing comfort in this paper. There were 72 rectangular nylon fabric samples involved in the experiment, and three key variables were introduced during the electrode preparation experiment, copper plating time, temperature, pre-stretching, where pre-stretching considered both warp and weft direction. The resistance of 72 samples at 30% stretch state was measured, SEM was used to characterize the copper plated fabric and copper plated fabric ECG electrodes were prepared and evaluated. According to the resistance statistics, the introduction of pre-stretching in the weft direction can bring better copper plating effects, and one sample (which was marked as D20/weft-1) showed the best electrical conductivity in the groups. Combined with SEM images, they all proved the success of copper plating on nylon fabric and that relatively low temperature and appropriate time are beneficial to copper plating. Simultaneously SEM inspection of MΩ-level high-resistance samples revealed that some of the copper plated particles were incompletely covered or peeled off. Finally, evaluating ECG waveforms and signal-to-noise ratios using fabric electrodes in natural and chest expansion state. Results showed that the fabric electrodes prepared from sample D20/weft-1 with excellent conductivity almost have the same performance as traditional Ag/AgCl electrodes. This study provides a cost-effective method and low-cost alternative for electrodes to record high-quality ECG both at home and in the clinic. [ABSTRACT FROM AUTHOR]

In the processing technology of printed circuit boards, the common electroless copper plating technology of ethylenediaminetetraacetic acid disodium (EDTA-2Na) has the problems of large surface stress, uneven crystal particles, and large surface roughness of the copper plating layer. To remedy the above shortcomings and meet the current requirements for copper interconnects in printed circuit boards (PCBs), the present study has investigated a chemical copper plating system that combines a high deposition rate with low stress. An electroless copper plating was then performed on a polyacrylonitrile-butadiene-styrene (ABS) plastic resin plate with 2,6-diaminopyridine (2,6-DAP), 2,2-bipyridine, sodium hydroxyethyl sulfonate (SHES) and NiSO4·6H2O as supplementary additives. By using scanning electron microscopy (SEM), electrochemical, atomic force microscopy (AFM), and X-ray diffraction (XRD) analyses, it has been shown that the average surface roughness Ra became reduced from 202 nm to 76.1 nm when using additives in the chemical copper plating process. Also, the internal stresses of the deposited copper layer on the (220) and (311) planes of a crystalline copper layer decreased from − 70.48 and − 53.03 to − 27.31 and − 27.16 MPa, respectively. The composite additive improved the quality of the copper layer of the EDTA-2Na-based chemical copper plating system, increasing the practical range of industrial applications and facilitating the subsequent application of higher-precision processing. [ABSTRACT FROM AUTHOR]

Ni/CNTs shielding coatings are obtained on the surface of polymethylmethacrylate (PMMA) by scraping and electroless plating. The effects of pH, temperature and electroless plating time on the structure and performance of the coating are studied through orthogonal experiments, which provide guidance for the optimization of the quality of Ni coatings in the production process. The relationship between the surface morphology attributed to the Ni particles on carbon nanotubes (CNTs) and the mechanism of electromagnetic shielding performance is discussed in depth. The mechanism of electromagnetic shielding depends on the content of Ni nanoparticles. When the content of nickel atoms on the surface is large, the reflection loss is dominant. At this time, a uniform and dense nickel coating with a scale-like structure can be obtained. The total shielding efficiency (SET) value of the corresponding Ni/CNTs coating with good salt resistance and a certain Joule heating performance can reach 40.9 dB. In contrast, when the content is small, the absorption loss is dominant. [ABSTRACT FROM AUTHOR]

The surface coating of magnetic nanoparticles onto hollow glass microspheres (HGMs) is of vital importance as light-weighted powders with wave-absorbing properties. In this study, HGMs were successfully coated by Co/Ni nanoparticles through a four-stepped strategy of NaF + HCl roughening, NaOH washing, PdCl2 activation, and electroless plating, successively. The soft roughening of SiO2 with NaF and the post-washing of Na2SF6 byproducts with NaOH were validated to ensure the integrity of the as-coated HGMs. The Ni–Co–P alloy coatings were measured to be lower than 1 μm in thickness with nanoparticles of 100–200 nm in diameter. The reflection loss of HGMs coated by 30 wt% Ni/Co not only retained the peak of the Co coating (− 4.5 dB) but also reached about − 6.7 dB at 16.4 GHz, much higher than that of HGMs coated by Ni and Co. The overall trend of input and output impedance ratio of the sample coated by Ni/Co does not change significantly compared with HGMs coated by Co, but the impedance matching has been optimized compared with Ni-plated powders. The novel light material with a uniform and complete coating prepared in this paper provides a new idea for the modification of HGMs for multi-functional applications. [ABSTRACT FROM AUTHOR]

In this work, a double-coating structure of C/Cu/NiP microfiber composites is designed through electroless plating and calcination at 300 °C and 400 °C temperatures to increase the interfaces and dipole polarization and enhance the electromagnetic microwave absorption performance as high-quality light microwave-absorbing materials. The maximum reflection loss value of C/Cu/NiP microfiber composites after the calcination at 300 °C is − 45.9 dB at 11.9 GHz with 1.7-mm matching thickness and 3.0-GHz effective bandwidth. This work demonstrates that the double-coating structure of carbon-based multifunctional materials can effectively optimize microwave absorption performance. [ABSTRACT FROM AUTHOR]

A facile and effective approach to fabricate a high-performance copper layer on polyphenylene oxide (PPO) substrate via electroless deposition for applications in the high-frequency circuit board is introduced in this study. Initially, a polydopamine coating was successfully formed on the surface of the PPO substrate after a micro-chemical etching by the combination of KMnO4 and KOH. Due to the high hydrophilic and strong adhesion of dopamine, the silver ions were uniformly adsorbed on the PPO substrate as a catalyst of electroless copper plating. Consequently, a metal copper layer with high reliability and strong adhesion is formed, which is characterized by optical microscopy, SEM, EDS, and XRD. The resistance of the deposited copper layer was about 2.74 μΩ cm (only block 1.68 times the resistance of copper-shaped copper), and the adhesion of the copper layer also reached the 5B score in the ASTM D3559 standard after the 100-grid peel test. This technique offers a dependable method to prepare a high-performance copper layer on the PPO substrate which has a great potential to be applied in functional electronics, including industrial polymer circuits and devices. [ABSTRACT FROM AUTHOR]

The carbon fibers with low density still face significant microwave absorbing application issues due to their high dielectric constant. Herein, C/Cu core–shell microfiber composites are prepared by electroless plating. The Cu coating of C/Cu core–shell microfiber composites is oxidized to CuO at 300 °C and 400 °C temperature. The morphology, microstructure, and electromagnetic characteristics of C/CuO microfiber composites were analyzed. The diameter of all the fiber composites was about 7–8 μm. The CuO coating thickness formed at 300 °C and 400 °C temperature is 30–90 nm and 300–900 nm, respectively. The annealing process tunes the electromagnetic characteristics and optimizes impedance matching. The minimum reflection loss (RL) value of C/CuO core–shell microfiber composites annealed at 300 °C temperature remarkably reaches − 46.0 dB at 1.06 mm thickness and 3.6 GHz effective absorption bandwidth (RL ≤ − 10 dB). The C/CuO microfiber composites can be the ideal absorbing materials at a lower thickness. [ABSTRACT FROM AUTHOR]

Embedded resistors in printed circuit boards (PCBs) are fabricated to provide high integration, improved electrical performance, and reduced parasitic capacitance and inductance in the high-frequency and high-speed environment. At present, the embedded resistance errors caused by etching metal film accuracy are generally more than 20%. In this work, real-time monitoring technology is developed to precisely control the resistance of electroless-plated embedded resistors. During the deposition process, the resistances of embedded resistors are monitored until reaching the targeted resistance, realizing the very ideal resistance error lower than 10%. Arbitrary shapes including serpentine and zigzag structures of embedded resistors are attempted to validate the practical capability of this approach. Reliability Characterization experiments such as high-temperature and high-pressure lamination, thermal shock and thermal cycles confirm the thermal and mechanical stability. It is demonstrated that the embedded resistors through real-time monitored electroless plating have tremendous potential in the manufacture of high-frequency and high-speed PCBs. [ABSTRACT FROM AUTHOR]

This paper presents a novel die attach material for power device packaging based on transient liquid phase (TLP) bonding. Through two-step electroless plating, the Cu@Sn@Ag particles were prepared, and realize interconnection with Cu Substrates after being compressed into preform. Due to the large specific surface area of the core–shell particles, the reflow time can be reduced to 15 min at a low temperature of 250 °C under a pressure of 3 MPa to form high-remelting-point intermetallic compounds (IMCs), which can withstand a high temperature of at least 475 °C. Due to the protection of the Ag coating, the Cu@Sn@Ag particles exhibited excellent oxidation resistance, and the bonding process can be carried out in the atmosphere. Then, the service reliability of the bondlines was evaluated in harsh environments, such as high temperature and humidity, high temperature storing, and thermal shock. The average resistivity of the bondlines was increased from 4.6 ± 1.4 to 8.5 ± 3.8 µΩ cm after being stored at high temperature (85 °C) and high humidity (85% RH) environment for 14 days. After storing at 300 °C for 15 days, the porosity of bondline increased from 6.8 to 10.8%, and the average shear strength decreased from 30.5 ± 6.3 to 22.3 ± 5.6 MPa. After thermal shock between − 40 and 125 °C for 500 cycles, the bonding rate decreased from 99.9 to 84.2%. Moreover, the short-circuit time of electrochemical migration under 60 V voltage was extended to 145 s. The bondline based on the novel core–shell particles exhibited excellent performance as a die attach material under harsh environments. [ABSTRACT FROM AUTHOR]

Flexible conductive glass fibers had widespread acquired attention in the field of electromagnetic interference shielding, sensor, and intelligent wearable devices. However, commercial fiberglass (FG) were insulators that greatly limit their application fields. Herein, flexible single FG with diameter of nearly 25 µm was manufactured by a home-made equipment. Then the surface of FG was further functionalized by dopamine self-polymerization and formed a polydopamine linker layer to chelate Ag(I) ion. Finally, the consecutive silver nanoparticles were coated on PDM/FG (polydopamine/fiberglass) via electroless plating method (Ag-PDM/FG). The SEM, XPS, and XRD results demonstrated that the silver layer on the FG surface was compact, uniform, continuous, and in a metallic crystal state. The Ag-PDM/FG exhibited excellent electrical conductivity as high as 2.49 × 106 S m−1 and could easily operate as a conductive wire for a LED device. Furthermore, the Ag-PDM/FG maintained its original conductivity even under various bending angles due to the stable Ag-coated layer. This work opens a new avenue for preparing flexible, continuous, and conductive FG with easy operation for wearable devices. [ABSTRACT FROM AUTHOR]

To enhance the effects of electroless Ni–P plating on inhibiting atom diffusion in Sn-58Bi joint systems, adding nano-sized metals into coating was regarded as an efficient method. Therefore, Cu nanoparticles were chosen as the additive in current study, and the interfacial microstructure evolution of solder joints by doping Cu nanoparticles into Ni(P) electroless plating were investigated. Experimental results revealed that growth rates of IMCs at the joint interface remarkably decreased with increasing content of Cu nanoparticles. In the Ni(P)–0.8 g/L Cu based joint, transformation from (Ni,Cu)3Sn4 to (Cu,Ni)6Sn5 occurred since more Cu atoms supplied by the coating participated in the interfacial reaction between solder and coating. Meantime, sizes of IMC grains at each isothermal aging stage decreased with increasing content of Cu nanoparticles, which could be attributed to introduction of potent nuclei. The IMC growth was mainly volume diffusion-controlled and followed parabolic laws. Diffusion coefficients were analyzed to be 1.18 × 10–2 μm2/h, 2.89 × 10–4 μm2/h and 2.56 × 10–4 μm2/h in Ni(P), Ni(P)–0.4 g/L Cu and Ni(P)–0.8 g/L Cu-based joint systems, respectively, suggesting that diffusion coefficient gradually decreased with increasing content of Cu nanoparticles. [ABSTRACT FROM AUTHOR]

The most common method for preparation of catalytically active free-standing hybrid material (CAFH) is that supporting material is formed and subsequent catalytic agent deposited on its surface. But it remains challenging to agilely prepare CAFH with different shape and size. We employ a facile process combined with defect-induced electroless nickel plating and selective laser sintering (SLS) forming to fabricate CAFH. Results manifested CH3COOH-etched treatment resulted in the formation of defect (amorphous structure, amide group and hole) on the Nylon 12 (PA12) surface, which would induce electroless Ni plating. The mechanism of the electroless plating is the destruction of the structure of [C6H5O73−-Ni] ligand around defect; subsequently, the reduction of the REDOX barrier. The following laser sintering of the plated PA12 powder could fabricate CAFH with an irregular network. There are two stages during the SLS process: balling of particle and formation of sintered neck. The combination of the structural stability, high surface area and recyclability gives a CAFH with demonstrated catalytic property. CAFH is agile to prepare, easy for quick-to-assemble material and realizable in CAFH shape design. The new technology possesses vast exploration and application value. [ABSTRACT FROM AUTHOR]

In order to alleviate volume changes of silicon monoxide during lithium insertion and improve its electrical conductivity, ball milling(bm)-SiOx/(Cu,Ni) lithium-ion battery anode materials are successfully prepared by depositing copper and nickel on the surface of silicon nanoclusters of silicon monoxide by electroless plating. The composition and morphological characteristics of the prepared materials are characterized by XRD, XRF, XPS, TEM, and EDS, and the electrochemical performance behavior of the materials are investigated by electrochemical tests. The results show that when the particle size of SiOx is reduced from 1.7 μm to less than 200 nm by ball milling, its initial specific capacity and reversible specific capacity can be significantly improved. The deposited Cu/Ni contents of bm-SiOx/(Cu,Ni) can be controlled by adjusting the concentration of Cu2+/Ni2+ in the plating solution. Both bm-SiOx/Cu and bm-SiOx/Ni can improve the initial discharge specific capacity, cycling stability, and rate performance. Bm-SiOx/Cu with a Cu content of 4.76% and bm-SiOx/Ni with a Ni content of 4.29% have the best electrochemical performance. Compared with bm-SiOx/Cu (4.76%), bm-SiOx/Ni (4.29%) has better electrochemical performance; at 0.1C rate, its initial discharge specific capacity can be achieved 2199 mAh/g. After 50 cycles, its reversible specific capacity is 1339 mAh/g. [ABSTRACT FROM AUTHOR]

An easy and effective method for the preparation of a new impedimetric sensor used in the detection of dimethyl sulfide (DMS) at a nanomolar level is presented. The sensor was prepared in two steps from a commercially available screen-printed carbon electrode (SPCE): a simple activation of the SCPE using cyclic voltammetry followed by electroless plating of the working electrode surface with gold clusters. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) techniques confirmed the successful functionalization of the SPCE, revealing the presence of gold particles dispersed on the carbon matrix. Electrochemical impedance spectroscopy (EIS) was used to study the sensitivity of the sensor towards DMS dissolved in aqueous solution and simulated ocean water. Analyses were performed in less than 3 min, and the sensor showed linearity in a concentration range from 1.0 × 10−10 to 1.0 × 10−8 M with a limit of detection of 1.50 × 10−9 M and a limit of quantification of 2.27 × 10−9 M. To simulate the marine environment in which DMS is naturally present in nature, the impedance of the sensor was monitored by online EIS. Moreover, results indicated that, despite not linearly, the sensor is a promising tool to detect the analyte even at 1.0 × 10−11 M, presenting an increase of resistance of 13.5% in relation to its bare condition. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) possess superior catalytic abilities and high surface area. Moreover, energetic particles can be loaded on them by acting as carriers. The current study reports an electroless plating, effective deposition of copper particles (Cu) on the surface of CNFs. The prepared Cu–CNFs hybrid was annealed at 250 °C to form CuO–CNFs. Homogeneous loading of CuO particles on CNFs was revealed via TEM analysis, while the crystalline structure was studied using XRD analysis. In addition, ammonium perchlorate (AP) oxidizer with endothermic initial decomposition was mixed with the synthesized CuO–CNFs hybrid. Moreover, uniform distribution of AP on CuO–CNFs hybrid was verified using SEM microscopy. While DSC and TGA were used to determine CuO–CNFs catalytic performance, our results showed that only 1 wt % of CuO–CNFs could decrease the endothermic decomposition of AP by 12.7%. Moreover, the two main stages of exothermic decomposition were combined into one with 80% increase in the total generated heat. To sum up, our results clearly revealed the promising catalytic capabilities of CuO–CNFs for the applications of solid propellants. [ABSTRACT FROM AUTHOR]

In this work, silver nitrate, thiourea, bisphenol A diglycidyl ether (BADGE), and propylene glycol methyl ether (PM) were selected for designing a silver(I)-complex to trigger the deposition of inductance coil on PET film through electroless copper plating. The most stable silver(I)-complex structure is formed when the ratio of thiourea molecules and silver ions is 3 to 1 by quantum chemical calculations based on density functional theory (DFT). Meanwhile, XRD test demonstrates that the white precipitate crystallized from PM solution of thiourea and silver nitrate is [Ag(SC(NH2)2)3]NO3, which is consistent with theoretical calculations. The cross section of PET film with copper patterns and interconnection holes characterized by metallurgical microscope proves that the silver(I)-complex is able to initiate copper deposition on the surface and through hole wall of PET film. The measured inductance values at operating frequency from 1 to 50 MHz indicate that the fabricated flexible inductor is capable of being integrated into flexible electronics when the bending angles are within 45°. Additionally, the inductor can also be utilized as an angel sensor when the bending angles are in the range of 60° to 180° at 10 MHz. [ABSTRACT FROM AUTHOR]

To deal with the electromagnetic radiation, a bio-based shielding material with dissimilar surface resistivity was fabricated by electroless Ni–Fe–P plating on bamboo surface. The effects of plating parameters, such as pH, main salt mole ratio, etc. on the deposition rate, resistivity, and chemical composition of the coating were investigated. The SEM, EDS, XRD, and XPS were used to study the surface morphologies, chemical composition, and crystal structures of the optimal coating. Besides, the results of electrical conductivity, magnetism, and shielding effectiveness (SE) showed the bamboo was endowed with good conductivity, magnetism, and SE after plating. Thereinto, the SE of plated bamboo was higher than 55 dB (0.1 MHz–2.0 GHz), which far surpassed the targeted value of 20 dB for commercial applications. Additionally, the corrosion property and thermal stability of material were also concerned. The TGA results displays the thermal stability of Ni–Fe–P-coated bamboo was enhanced compared with raw bamboo. Moreover, we found the alloy was not simply surface-coated but permeated into bamboo because of its porosity. Furthermore, an interesting phenomenon has been found for the first time: the Ni–Fe–P-coated bamboo has the characteristic of surface resistivity dissimilarity which could be reflected in different structures, different planes, and different locations. [ABSTRACT FROM AUTHOR]

Lightweight ordered mesoporous carbon (OMC) flakes have been successfully synthesized by an evaporation-induced self-assembly route. The highest specific surface area and pore volume of the OMC flakes reach 1727 m2 g−1 and 2.05 cm3 g−1, respectively. The results of the complex permittivity show the OMC/paraffin composites have high dielectric loss in the frequency range of 2–18 GHz. In order to enhance the microwave absorption properties of the OMC materials, an electroless plating method is exploited to deposit Fe particles on the OMC flakes. Benefiting from the magnetic loss and improved impedance characteristic, the OMC/Fe composites display excellent microwave absorption properties. The minimum reflection loss of the OMC-700-Fe composite reaches − 65.3 dB at 10.1 GHz and the absorption bandwidth < − 10 dB is up to 4.7 GHz (8.7–12.4 GHz) with the absorbing thickness of 2.5 mm. When the thickness is from 1.8 to 5.5 mm, all of the peak values of reflection loss are < − 20 dB. This work provides a new opportunity for the fabrication and design of lightweight microwave absorbers. [ABSTRACT FROM AUTHOR]

ZnS has been widely used as a material for windows in optical systems. This is because it has a good transmittance in both mid-infrared and far-infrared bands, a stable chemical performance, a moderate linear thermal expansion coefficient and an adequate mechanical strength. ZnS windows need the so-called splice technology implementation to satisfy the integrity of large size applications or special surface structures. Traditional ZnS light windows are mechanically assembled with metal frames. However, the strength of the large-size ZnS formed by mechanical assembly is low. Consequently, an adequate joining technology is needed to overcome the low splice strength and improve the mechanical strength of the assembly. In this paper, we proposed a pre-metallization method by using an electroless plating of Ni on ZnS surface. Subsequently, a low temperature joining by using a Sn63Pb37 solder was completed. By a study of the process and the corresponding mechanism of the electroless nickel plating, a Ni–P layer with a controllable P content and thickness has been formed, and a smooth surface and a good combination with ZnS has been obtained. The microstructure of the Sn63Pb37 and Ni–P/ZnS was analyzed, and the phase composition and element distribution within the joint were determined. The influences of process parameters on the microstructures of the joints have been explored, including the brazing temperature, the time of thermal energy preservation and the thickness of the coating. Finally, the shear strengths of joints under different imposed parameters were optimized leading to the peak soldering temperature of 250 °C and the dwell at the peak of 1 min. The fractures were along Ni–P/ZnS ceramic interface, therefore, a successfully low temperature joining process on ZnS ceramics using Ni–P plating and Sn63Pb37 solder had been performed. [ABSTRACT FROM AUTHOR]

Thermoelectric material is a new functional material that can convert thermal energy into electrical energy, and it has been widely concerned because it can be used as alternative energy in many applications. Bi2Te2.4Se0.6 nanopowders were prepared by electroless plating, and then sintered into bulk by spark plasma sintering. After electroless plating, the thermal conductivity of n-type Bi2Te2.4Se0.6/Cu thermoelectric materials has been significantly reduced due to decreased electronic thermal conductivity and phonon scattering caused by large grain boundaries and defects, of which 0.15 wt%Cu/Bi2Te2.4Se0.6 has the lowest lattice thermal conductivity and reached 0.43 W m−1 k−1. The results show that the average zT value of all components has been enhanced to a certain extent, of which the average zT value of 0.15 wt%Cu/Bi2Te2.4Se0.6 reached 0.89, and the peak zT reached 0.98 at 401 K. [ABSTRACT FROM AUTHOR]

A thin layer of silver was prepared on cellulose film (CF) surface via electroless plating to obtain high electromagnetic shielding effectiveness Ag/cellulose composite layer. The process is simple, efficient and low-cost. The developed film has a great advantage in electric conduction and electromagnetic interference (EMI) shielding. The identical deposit of thin silver layer was perfectly fabricated via the electroless plating on the CF surface. The fabricated thin silver layers were tested for electrical properties and EMI SE. The electrical and electromagnetic shielding properties of the thin silver layer were ideal when the activation concentration was 100 Mm (mmol/L). Herein, the resistance and conductivity of Ag/cellulose composite films can reach 0.35 Ω and 45 s/cm, respectively, and the EMI SE of Ag/cellulose composite films can be up to 67 dB ranging from 0.0003 to 3 GHz. The dielectric constant (ε′) of the Ag/cellulose composite film was between 6.5 and 7.5, which was stable throughout the test band ranging from 2 to 18 GHz. The permeability (µ′) of the Ag/cellulose composite film was around 1 ranging from 2 to 18 GHz. [ABSTRACT FROM AUTHOR]

It is highly desired to simplify the technology of electroless plating on inert polymer. Herein we developed a new kind of catalytic solution (mixture of H2O, AgNO3 and 3-aminopropyltriethoxysilane), which can write onto inert polymer directly with good stability, resolution and catalytic performance. Then, a facile method combined with catalyst solution printing and electroless plating to fabricate selective metal (copper and nickel) coating on polymer (polypropylene and polyethylene terephthalate) surface. The growth behavior, electrical, and structural properties of plated coating were investigated. The minimum width of copper coating is 250 μm, thickness is 2.2 μm, resistivity is 2.6 × 10−6 Ω cm, adhesion of 2.2 μm thick coating maintain 5B. In addition, the selective metal coating have excellent bending and fatigue resistance. [ABSTRACT FROM AUTHOR]

In order to produce conductive poly(benzo)-benzimidazole (PBO) fibers with corrosive resistance, copper plating on the surface of PBO fibers was carried out via palladium-free activation by electroless plating, followed by partial reduced graphene oxide (rGO) coating via electrophoretic deposition (EPD). The morphology, element composition and crystal structure of copper plated PBO (Cu/PBO) fibers were studied by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction, respectively. Effect of deposition time on the deposition rate of copper, deposit weight and electrical resistance of Cu/PBO fibers was investigated. In addition, electrical conductivity and heat generation of Cu/PBO fibers were evaluated. The surface of PBO fibers is uniformly and densely covered with spherical copper particles and Cu/PBO fibers possess excellent conductivity with the electrical resistance of 2.98 × 10−3 Ω m for deposition time of 70 min. The corrosion resistance of reduced graphene oxide coated copper plated PBO (rGO/Cu/PBO) fibers was studied by Tafel analysis. The corrosion potential has a negative shift of 31 mV (from − 240.2 to − 209.2 mV) and Icorr reduces from 4.34 µA/cm2 for Cu/PBO fibers to 1.24 µA/cm2 for the rGO/Cu/PBO fibers. The results indicate that the rGO coatings on Cu/PBO fibers can protect copper coating against corrosion. The results indicate that rGO/Cu/PBO fibers possess excellent electrical conductivity and corrosive-resistance, which could be used as conductive flexible materials with corrosive resistance. [ABSTRACT FROM AUTHOR]

In this work, the interfacial reactions and IMC growth of the Sn-35Bi-1Ag on Cu, Ni-P/Cu and Ni-Co-P/Cu were studied during reflowing at 220 °C for 10 min and solid-state treatment at 150 °C with various aging times. For the solder joints of Sn-35Bi-1Ag/Cu, Cu6Sn5 IMC was formed at the interfacial layer after soldering, while Cu3Sn appeared after aging treatment. In the case of the electroless Ni-P plating of Cu, the IMC formed at the interface during isothermal aging was mainly Ni3Sn4 and a small amount of P-rich Ni (Ni3P) layer between the Ni3Sn4 IMC and the electroless Ni-P plating layer. In the case of the electroless Ni-Co-P plating of Cu, the IMC formed at the interface during isothermal aging was mainly (Ni, Co)3Sn4 and a small amount of P-rich Ni ((Ni, Co)3P) layer between (Ni, Co)3Sn4 IMC and the electroless Ni-Co-P plating layer. The addition of Co atoms could effectively inhibit the IMC growth rate, which inducing a lower growth rate of (Ni, Co)3Sn4 than that of Ni3Sn4. The thickness of Ni3P and (Ni, Co)3P layer reached about 2.31 µm and 1.25 µm after aging for 360 h, respectively. Also, the growth kinetics of the Ni3P and (Ni, Co)3P layer was found to be a diffusion-controlled process, which followed a parabolic relationship in the thickness increase. During the aging, the consumption of the electroless Ni-Co-P plating layer was greatly reduced compared with that of the electroless Ni-P plating layer. Moreover, there were no voids observed in the electroless Ni-Co-P plating layer while some defects formed in that of the electroless Ni-P plating layer. The electroless Ni-Co-P plating layer will be a good diffusion barrier for the lead-free soldering. [ABSTRACT FROM AUTHOR]

Kevlar fabric was pretreated with aminopropyltrimethoxysilane (APTMS) through supercritical carbon dioxide (scCO2) process before electroless nickel plating. APTMS pretreated Kevlar fibers were characterized by element distribution and contact angle. Deposition rate, deposit weight, surface morphology, crystal structure, surface resistance, electromagnetic interference shielding effectiveness (SE) and magnetic properties of electroless nickel plated Kevlar fabric were investigated. The results show that APTMS is evenly covered on Kevlar fibers after pretreatment. Nickel coatings on the Kevlar fibers are dense and uniform after nickel plating. Surface resistance and electromagnetic interference SE of the nickel plated Kevlar fabric via scCO2 processes arrives at 1.33 Ω/sq and 13-19 dB at frequencies ranging from 2 to 18 GHz. The saturation magnetization of Ni coated Kevlar fabric reaches 207.52 memu/g. [ABSTRACT FROM AUTHOR]

Efficient electromagnetic interference (EMI) shielding performance for sealing materials exposed to the environment has become an increasing requirement in the precision electronics, aerospace and military applications. Nowadays, it is still a big challenge to prepare EMI shielding seal material with recyclable and low cost characters. Herein, the flexible polypropylene/ethylene-propylene-diene monomer/nickel coated glass fiber (PP/EPDM/NCGF) shielding composite is fabricated via electroless deposition and melt-reactive blending method. The Ni layer coated on the surface of glass fiber constructs a 3D conductive network in the composite ascribed to the well-connected glass fiber skeleton. The composite exhibits an EMI SE of 22.2 dB and elongation at break of 126.5% by adding only 1 vol% Ni (16.36 vol% NCGF). The good mechanical property and satisfied EMI shielding effectiveness suggest that TPV/NCGF is a promising substitution to fabricate recyclable, lightweight and low cost shielding seal materials. [ABSTRACT FROM AUTHOR]

In this work, stress behavior in nickel-plated coating on poly(ethylene terephthalate) (PET) substrate modified with primer was investigated using X-ray diffraction, scanning electron microscopy and optical microscope. Results showed residual stress of plated coating were firstly enhanced, and then reduced with the increase of plated time. The residual stress could lead to stress cracking phenomenon, which results in partially release of the residual stress. In addition, the initial cracking time, residual stress and fracture stress obviously increased with increasing activated time. When the modified PET substrates activated for 2 and 60 min, highest residual stress were 3.7 and 4.6 MPa, fracture stress were 3 and 4.1 MPa, initial cracking time were 15 and 20 min after electroless plating, respectively. Further investigation indicated that the residual stress was probably related to the crystal preferential orientation, deposited rate, catalyst amount. [ABSTRACT FROM AUTHOR]

In this work, the electroless nickel plating on Nylon 12 (PA12) powders was developed. The effect of ultrasonic vibration on activation-electroless plating on PA12 powders were investigated systematically using scanning electron microscopy and X-ray diffraction. Results showed amine groups attached on the surface of KH550-modified PA12 powders. The surface structure of modified powders could adsorb the tin and palladium ions, which used as catalyst for the Ni plating. Ultrasonic vibration-assisted activating would facilitate the adsorption of Pd atoms on the surface of PA12 powders, however, hinder nickel atoms plated on the PA12 surface. When the PA12 powders were plated with and without ultrasonic vibration, the palladium content of activated powders were 0.15 and 0.04%, the nickel content of plated powders were 4 and 10%, amorphous shells and nickel particles plated on the surface of PA12 powders, respectively. [ABSTRACT FROM AUTHOR]

High performance microwave absorber consisting of Fe@Ni nanoparticles (NPs) modified reduced graphene oxide (RGO) and epoxy resin was successfully prepared. Fe@Ni NPs obtained via electroless plating method could be simply anchored on the surface of RGO sheets because of its high surface area, as well as residual organic groups of RGO. The crystal/micro-structure and magnetic properties of as-synthesized samples were subsequently analyzed by XRD, SEM, TEM, XPS and VSM, while electromagnetic properties were tested by vector network analyzer. The synergistic effect between graphene and Fe@Ni NPs generated suitable impedance match and strong microwave attenuation ability which lead to excellent microwave absorption property. The optimal reflection loss (RL) calculated from measured electromagnetic parameters can reach up to − 22.7 dB at 14.9 GHz with a layer thickness of 2 mm. Moreover, RL values < − 10 dB is found to be 5.5 GHz within 12.5–18 GHz, almost covering the entire Ku band. It’s convincing that the as-synthesized composites are potential candidates for high-performance lightweight microwave absorbers. [ABSTRACT FROM AUTHOR]

Polyester fabric was catalyzed with Nickel(II) acetylacetonate (Ni(acac)) in supercritical carbon dioxide (scCO) prior to electroless copper plating . The nickel activated polyester fibers were then characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. Deposited weight, surface morphology, crystal structure, surface resistance, electromagnetic interference shielding effectiveness and thermal loss of the copper plated polyester fabrics catalyzed with nickel in scCO were investigated. The results indicate that the amount of copper deposited onto polyester fabric catalyzed with Ni(acac) in scCO is much more than that without scCO. Deposition rate of copper particles onto polyester fabric increases with increased temperatures of scCO. The copper particles are uniformly coated on the polyester fibers. The surface resistance of the copper plated fabric is 50 mΩ/sq when the temperature of scCO is increased to 90 °C. The electromagnetic interference shielding effectiveness of the copper plated polyester fabric is 60-80 dB at frequencies ranging from 2 to 18 GHz. These results suggest that catalysis in scCO for electroless copper plating provides polyester fabric with excellent electrical conductivity, surface resistance and electromagnetic interference shielding effectiveness. [ABSTRACT FROM AUTHOR]

Electroless Ni/electroless Pd/immersion Au (ENEPIG) constitutes a promising metallization to replace the conventional ENIG or Ni/Au for 3D IC integrated module and optoelectronic packaging. Different ENEPIG plating thicknesses with copper pillar solder joints are subjected to thermal aging at 150 °C to investigate the intermetallic compounds (IMCs) formation and growth. Due to low temperature solid-state bonding, both Pd and Au layers do not completely diffused into Sn matrix and participated in the interfacial reactions to form (Pd,Au)Sn IMCs phase. (Pd,Au)Sn IMCs based on PdSn phase with dissolved Au, exhibits high growth rate and substantial consumption of Sn from solder. Upon increasing the aging time, it is found that (Cu,Ni)Sn IMCs and (Pd,Cu,Au)Sn4 phase form at interface and follows a diffusion control mechanism, which weakened the solder joint and caused brittle fracture in a die peel test. (Cu,Ni)Sn IMCs growth rate increases with decreases Pd thickness. Therefore, the types of IMCs formation, growth rate, and reliability of Cu pillar joint strongly depend on bonding temperature, Au and Pd thicknesses, and solder volume. Based on this study, the authors recommend suitable ranges of Au and Pd layer thicknesses for reliable Cu pillar solder joints. [ABSTRACT FROM AUTHOR]

In this work, region-selective electroless nickel plating on poly(ethylene terephthalate) (PET) substrates and through holes modified with primer was developed. Results showed active groups formed on the modified PET surface, which could absorb the Sn atoms and Pd atoms via chelation. It was observed that the plated coating possessed significant residual stress, and the following heat treatment can partially release the residual stress. As a result, the selective, good adhesion and flexible plated coatings were obtained successfully after heat treatment and then laser etching. The minimum width of nickel lines and spacing between nickel lines were 0.25 and 0.15 mm, respectively. In addition, the nickel coating could plate on inside of the through hole modified with primer, leading to a good conductivity of both sides of plated PET. [ABSTRACT FROM AUTHOR]

Hollow glass microspheres (HGMs) double-coated with Co-Ni/FeO composite has been successfully prepared by electroless plating and coprecipitation method, which is applied to the microwave absorption materials. The surface morphology, structure, magnetism, electromagnetic property of the products have been characterized by scanning electron microscope, X-ray diffraction, vibrating sample magnetometer and vector network analyzer, respectively. The results show that the outer surfaces of HGMs were coated by continuous and uniform layers of Co-Ni/FeO. The maximum magnetization and coercivity values of HGMs/Co-Ni/FeO composite increase to 19.46 emu/g and 505 Oe, with a maximum applied magnetic field of 10 kOe. The dielectric loss and magnetic loss of the composite increase remarkably in the frequency range of 1-18 GHz. The maximum microwave reflection loss could reach −35.4 dB at 6.7 GHz (C-band) with 1.81 GHz bandwidth below −10 dB. [ABSTRACT FROM AUTHOR]

Co-coated hollow carbonyl iron particles were prepared by a method combining pitting corrosion and electroless plating. The comparison of morphology from images of SEM, phase composition, magnetic property and apparent density of initial and processed particles before and after heat treatment demonstrated the low density and high antioxidation properties after processing, which proved Co coating acts as a protection layer. The complex permittivity and complex permeability of raw carbonyl iron, hollow carbonyl iron and Co-coated hollow carbonyl iron particles were measured and the mechanisms of varying electromagnetic parameters were analyzed. And the electromagnetic microwave absorption properties of raw carbonyl iron, hollow carbonyl iron and Co-coated hollow carbonyl iron particles were investigated in the frequencies during 2-18 GHz. The band width below −10 dB could reach 4 GHz and the minimum of reflection loss value could reach to −19.5 dB for the Co-coated hollow carbonyl iron particles, which can maintain a good microwave absorption property. [ABSTRACT FROM AUTHOR]

In this paper, user-defined copper conductive patterns were successfully fabricated via electroless deposition onto paper substrate by using a four-step treatment process. The pristine paper samples are first dipped in 3-aminopropyltrimethoxysilane (APTMS) solution to form a uniform layer for the subsequent absorption of gold nanoparticles. Then the paper samples were wax patterned and immersed in gold nanoparticles solution in preparation for the next step electroless deposition. Herein, wax pattern was achieved via a stylus printer to print desired stencil dot matrix, which acted as hydrophobic channels, onto the paper substrate. FT-IR measurement, ultrasonic washing test and Scotch-tape test were utilized to investigate the interaction mechanism between APTMS molecules and paper substrate. Contact angle measurement demonstrated that the hydrophobic surface of wax patterned paper. SEM images showed that the thickness of copper conductive patterns was estimated to be 2.44 μm, which was corresponding well with Surface Profiler measurement. X-ray diffraction analysis showed that the copper films deposited on paper substrate has a structure with Cu (1 1 1) preferred orientation and the resistivity of Cu patterns measured by a digital four-point probe was 6.8 µΩ cm, which was 4.2 times of the bulk Cu. Notably, only one cycle of printing wax on paper substrate could successfully regulate the deposition area of Cu films. Those above advantages make this method a promising candidate for applications in constructing functional flexible electronic devices. [ABSTRACT FROM AUTHOR]

Copper-coated glass fabric was successfully fabricated via electroless plating method, and the copper layer on the surface of glass fabric was continuous and compact. The chemical composition of the copper coatings was investigated by X-ray diffraction, and the microstructures were invested by scanning electron microscopy. It was found that the quality of the copper layer was closely related to the dosage of NaOH and reducing reagent, respectively. These composites possessed excellent conductivity with the volume resistivity up to 2.57 × 10 Ω cm, and can be used as shielding materials. [ABSTRACT FROM AUTHOR]

In order to enhance the oxidation resistance of a copper substrate, silver films were deposited by electroless plating onto pure copper nanopowder. However, the efficiency of electroless plating for nanopowders is very low. Silver-coated copper nanopowders can be successfully achieved by three-times electroless silver plating on copper nanopowder. The microstructure and the chemical composition of the silver-coated copper nanopowders were systematically analyzed. The silver films have shown excellent oxidation resistance, according to the results of accelerated temperature cycling tests. The silver-coated copper nanopowders were characterized using scanning electron microscopy and X-ray diffraction. Following conclusions were obtained under the optimum condition that the reaction temperature was 50 °C, the dosage of EDTA was 4 g/L, hypophosphite (NaHPO) was 20.6 g/L. When the silver content reached 25 %, silver was homogeneously distributed around copper nanopowders. [ABSTRACT FROM AUTHOR]

Conductive Cu patterns were constructed on flexible paper via selectively electroless plating method, which including multistep procedures, namely, 3-aminopropyltrimethoxysilane (APTMS)-modification, selective Cu-seeding and Cu-lines deposition. Herein, the Cu activation process could be divided into two stages: the Cu-absorption in cupric citrate solution and subsequently the Cu-reduction using a roller pen filled with sodium borohydride ink. The interaction of APTMS onto paper was confirmed by FT-IR measurement and the results indicated that the -NH groups originating from APTMS were grafted on the paper. The elemental analysis of the samples in each step was conducted using XPS measurement. Paper-based conductive patterns were investigated by SEM, XRD and Scotch-tape test. SEM images illustrated that the Cu lines on the APTMS modified paper substrate was compact and composed of ball-shaped copper nuclei. Moreover, the Cu lines could be selectively plated on the required area of the paper substrate. XRD analysis showed that the obtained Cu patterns had a structure with Cu (1 1 1) preferred orientation, revealing an excellent electromigration resistivity. The resultant Cu patterns exhibited an admired adhesion to modified paper, while the Cu patterns obtained in absence of APTMS modification suffered a failure in the adhesive Scotch-tape test. The resistivity of copper patterns characterized by the digital four-point probe was 10.3 µΩ cm, which was 6.3 times of the bulk Cu. Meanwhile, paper-based Cu pattern remained excellent conductivity after multifolding. Those results indicated that the method proposed in the present work offered a robust and efficient alternative to manufacture flexible electronics. [ABSTRACT FROM AUTHOR]

In this work, nickel/carbon fiber composites with excellent conductivity were successfully prepared by an electroless plating method in alkaline media, in which sodium hypophosphite was used as reducing agent. The composition, microstructure, electrical, and magnetic properties of samples were investigated by XRD, SEM, VSM, and four-probe meter techniques, respectively. It was found that the volume of aqueous ammonia and concentration of sodium hypophosphite played important roles on the microstructure of nickel coatings. The composites with compact and uniform nickel layer on the surface of carbon fiber possessed face-centered cubic phase, and the volume resistivity could reach 1.49 × 10 Ω cm. In addition, magnetic hysteresis measured at room temperature demonstrated that the nickel-coated carbon fiber composites showed ferromagnetic behavior with saturation magnetization ( M ) and coercivity ( H ) of 5.2 emu/g and 144.9 Oe, respectively. [ABSTRACT FROM AUTHOR]

Cu nanoparticles (CuNPs) were loaded on the surface of hollow glass microspheres (HGMs) by electroless plating technique. The surface morphology and composition of the plated HGMs were characterized by XRD, XPS and SEM. The results show that the size and distribution of the CuNPs varied with the different copper sulfate concentrations and played an important part in photocatalytic hydrogen production. When the concentration was 2 g/L, the hydrogen production reached 3845 μmol/g h with lactic acid as a sacrificial agent and exhibited great stability for at least 20 h, which is better than the freshly synthesized alone CuNPs (1500 μmol/g h). What's more, the photocatalytic degradation rate of methyl orange reached up to 95.75 % after 2 h under light irradiation and the photocatalysts can be recycled for further use. [ABSTRACT FROM AUTHOR]

As the electronic devices tend to be miniature and compact, the pitches both between the adjacent leads on printed circuit board (PCB) and between connectors' terminals mating with PCB reduces to the level of one tenth millimeter. With lead-free legislation impacting PCB manufacturing, immersion silver finish is adapted as one of the top finish of copper trace on PCB due to its many advantages. At the same time, driven by cost pressure, the silver electroplating is also considered to replace gold plating on electrical contacts of connectors. Therefore, there is a potential risk for silver finish to form electrochemical migration (ECM) under certain potential bias in high humid environment. The effects of the silver plating processes on PCB and connectors, and the thickness, porosity, defects of silver finish, as well as the underplating and substrate materials will increase the complexity of ECM. In this study, possible chemical reactions happened on the silver electrodes were analyzed theoretically based on the analysis of plating processes and detection of porosity and defects. The time to failure caused by ECM was quantitatively calculated by the change of surface insulation resistance between the electrodes with potential bias. The failure mechanisms of ECM both on electroless silver plated PCB and on silver electroplated conductors were compared by element compositions and growth stages of migration dendrites, as well as polarization performance of different material combinations. The influencing factors on ECM, such as the potential bias, the thickness of silver plating, underplating nickel, substrate copper, were also discussed. [ABSTRACT FROM AUTHOR]

This paper explores the fabrication of embedded resistor materials by acidic and alkaline electroless Ni-P deposition methods. The influences of different reaction parameters on deposition rate and Ni-P layer property are discussed. The alkaline deposition is more favored to fabricate embedded resistors for its better manufacturing controllability and layer corrosion resistance. Process capability is further assessed by fabricating resistors of different patterns. Relative standard deviation (RSD) of the square resistances is found decreasing with the resistor pattern, and can be controlled within applicable range without laser trimming. Furthermore, the fabricated embedded resistors can endure standard environmental reliability tests, which making them potential materials in printed circuit board manufacturing. [ABSTRACT FROM AUTHOR]

Ni-Fe-P ternary alloy coating was deposited on triplochiton sclexcylon veneers by electroless plating to prepare a magnetic, corrosion-resistant and electromagnetic shielding wood-based composite. The effects of solution pH and plating temperature on the deposition rate, surface resistivity, chemical composition and crystal structure of the coatings were investigated. The surface morphologies were observed by using scanning electron microscope and the chemical composition of the coatings were analyzed by energy dispersive spectrometer and X-ray photoelectron spectroscopy. The magnetism and corrosion resistance were measured by vibrating sample magnetometer and potentiodynamic corrosion measurement. The results show that the deposition rate increases with pH value increasing from 8.6 to 9.2 and temperature increasing from 70 to 90 °C. The coatings obtained at experimental condition are all crystalline. The coating is mainly consisted of Ni, Fe and P, but the surface is coated by the component of the plating solution. The coatings are uniform, continuous and compact, and the special structure of wood is still seen clearly. The veneer-based composite exhibits higher corrosion resistance and magnetism. The ESE value reaches 40-60 dB in frequencies from 9 kHz to 1.5 GHz. This work provided a new pathway for producing multifunctional wood-based composite. [ABSTRACT FROM AUTHOR]

Silver-coated glass fibers have been successfully fabricated using a simple electroless silver plating. The structures of the silver/glass fiber composites were characterized by X-ray diffraction, high-resolution transmission electron microscopy, and scanning electron microscopy, respectively. The morphology investigation showed that the silver coatings were compact and continuous. The minimum volume resistivity could reach 4.53 × 10 Ω cm, suggesting excellent electric conductivity. It was found that the quality of silver deposition was influenced by dosage of ammonia solution and plating temperature. Ammonia solution served as complexing reagent and supplied an alkaline media, and higher temperature easily led to metallic oxidation. The current method is simple-handle, inexpensive, large production, and the obtained silver/glass fibers can be used as fillers to fabricate electromagnetic wave shielding materials. [ABSTRACT FROM AUTHOR]

Electroless Ni-P under bump metallization (UBM) has advantages of even surface, low cost and simplicity to deposit, but their mechanical strength, corrosion resistance and stability still face challenges under high soldering temperature. Incorporating carbon nanotubes (CNTs) into electroless Ni-P UBM might be expected to provide Ni-P-CNT composites with high mechanical strength and stability. Ni-P-CNT composite coatings as well as Ni-P coatings were fabricated by electroless plating process. In order to homogeneously disperse CNTs in composite coatings, acid pre-treatment and surfactant dispersant were introduced. During composite electroless plating, the ultrasonic agitation was also employed. In this study, scanning electronic microscopy (SEM) was used to observe the morphology and the CNTs were proved to be uniformly distributed in Ni-P-CNT coatings by SEM and atomic force microscopy. It was verified that the surface of the composite was quite smooth and continuous; CNTs are equably embedded in the matrix, which is advantageous for conductivity, mechanical strength and corrosion resistance. Shear tests were conducted to evaluate the effect of CNT reinforcement on the mechanical properties of joints, and the joints with CNT additions exhibited higher shear strength at different reflow cycles. Moreover, deposition mechanism of CNTs with Ni was analyzed and confirmed by transmission electron microscopy. Factors that affecting plating process was also discussed, and the optimum plating condition was suggested in this study. [ABSTRACT FROM AUTHOR]

A simple electroless copper plating process was employed to prepare copper-coated glass fibers with excellent conductivity. The glass fibers were pretreated by etching, sensitizing, and activating procedures. Disodium ethylenediamine tetra acetate (EDTA-2Na) and hydrazine hydrate (NH·HO) were employed as complex reagent and reductant, respectively. It was found that the copper deposition was greatly influenced by dosage of EDTA-2Na, concentration of sodium hydroxide (NaOH), temperature, and volume of NH·HO. The optimal temperature for electroless copper plating ranged from 40 to 60 °C. The composites were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques. The result showed that the minimum volume resistivity of 0.0010 Ω cm was obtained for the sample with perfect copper coatings on the surface of glass fibers. This method is simple, low-cost, and large production, and can be extended to fabricate other metal-coated glass fibers with distinct conductivity. [ABSTRACT FROM AUTHOR]

The effects of manganese sulfate monohydrate (denoted as MSM) on the properties of electroless Ni-P thin-film were investigated. The properties of Ni-P thin-film were examined by means of atomic force microscopy (AFM), cyclic voltammetry, scanning electron microscopy (SEM), X-ray diffraction, energy-dispersive X-ray spectrometer and X-ray photoelectron spectroscopy. AFM and SEM results showed that MSM had significant influences on the morphology, including the formation of smaller nodules, nano-size particles boundaries on both surface and inside of nodules. Due to the specific topologies, the resistance of Ni-P thin-film deposited with MSM was increased. Based on the characterization results, we summarized that the Mn or Mn-compound were primarily confirmed to act as the stabilizer in Ni-P electroless process. Moreover, the verification test for Ni-P thin-film in application as embedded resistor was carried out through electrical, thermal stability examination by means of current-voltage (I-V), temperature coefficient of resistance and thermal shock tests, respectively. Experiment results demonstrated the Ni-P thin-film deposited with MSM is qualified for embedded resistors. [ABSTRACT FROM AUTHOR]

An efficient method for the fabrication of flexible copper clad laminate (FCCL) on poly(ethyleneterepthalate) (PET) sheet by electroless plating was developed. This method relies on PET surface grafted 1,2-ethylenediamine (EDA) layer, which is employed as an adhesive interlayer for the manufacture of FCCL. Au catalysts were adsorbed on the EDA treated PET sheet and subsequently initiate the deposition of copper in an electroless plating solution. Attenuated total reflection fourier transformation infrared (ATR-FT-IR) spectroscopy, water contact angle, X-ray photoelectron spectroscopy, and atomic force microscope were employed to trace the surface changes during the grafting process with water, ethanol or dimethyl sulfoxide (DMSO) as solvent. For the PET sheets grafted from ethanol and DMSO solution, the prepared copper layers show strong adhesion to the substrate, which can pass Scotch tape test, while the sample grafted from water solution fail. All results indicate that using ethanol or DMSO as solvent for EDA grafting is benefit for the preparation of FCCL, and the adhesive improvements are due to an increase in the surface roughness of PET sheets and the amount of gold particles adsorbed on PET surface which act as nucleation and anchor sites for copper. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNT) decorated with Ni and Ag performed by electroless plating, and the effect of Ni and Ag nanoparticles and coating distribution on field emission of CNT are studied. The chemical composition, microstructure of CNT/Ni and CNT/Ag nanocomposites are characterized by an energy dispersion X-ray spectroscope (EDS), a transmission electron microscope and a scanning electron microscope. The field emission properties of CNT/Ni and CNT/Ag cathodes are measured using a diode structure under a pressure of 10Pa. The experimental results show that fine and well-dispersed metallic nanoparticles and discontinuous coating of Ni and Ag on the CNT surface can be obtained by electroless plating. Moreover, the enhanced field emission properties of CNT decorated with Ni and Ag can be obtained by lowering the work function of emitters and reducing the contact resistance between cathode and substrate. The field enhancement factors as high as 24264 of CNT/Ni and 25565 of CNT/Ag emitters can be improved by the distributed nano-sized Ni and Ag formed on the CNT surface. [ABSTRACT FROM AUTHOR]