Dali Mao

• Shanghai Jiao Tong University

As the continuous shrinkage of the interconnect line width in microelectronics devices, there is a growing concern about the electromigration (EM) failure of bonding wire. In addition, an innovative Ag-8Au-3Pd alloy wire has shown promise as an economical substitute for gold wire interconnects due to the cost pressure of gold in the last decade. In...

The SiO2–Nafion/sulfonated poly (ether ether ketone) (SPEEK) composite membranes are fabricated by using the simple mechanical ball-milling process to combine SiO2 glass powders with small portion of Nafion, in which SiO2 glass powders are prepared by modified sol–gel progress and Nafion is embedded in situ into a highly porous silica network. The...

An innovative Ag–8Au–3Pd alloy wire has been developed as an alternative to the traditional gold wire bonding. This paper focused on the free air ball (FAB) formation of 0.7 mil Ag–8Au–3Pd alloy wire, which was vital for the yield of the subsequent bonding process. During electric flame-off (EFO) process, the wire tail was melted by a high voltage...

Ag-8Au-3Pd alloy wire has shown promise as an economical substitute for gold wire interconnects from integrated circuits to substrates. This work is undertaken to gain a better understanding on the intermetallic compounds (IMC) formation and evolution at the interface between Ag-8Au-3Pd wire and Al metallization pad. Longitudinal cross-section of b...

AZ31B Mg alloy sheets were rolled by seven passes with pass reduction of 15% at 250 °C. The specimens were deformed by normal cast-rolling and combining energy-field cast-rolling (electromagnetic field and ultrasonic). Both microstructure and texture of two kinds of Mg sheets during whole rolling process were analyzed. The results show that in comp...

Ag-8Au-3Pd alloy wire has great potential of low-cost candidate for traditional gold wire interconnects. This study aims to light the behavior of degradation that took place in Ag-8Au-3Pd alloy wire bond interface. Two layers of intermetallic compound (IMC) at the Ag-8Au-3Pd/Al bond interface were observed by transmission electron microscopy (TEM)....

Influence of Cr alloying on the oxidation behavior of Sn–8Zn–3Bi–xCr (SZBxCr) (x = 0, 0.1, 0.3, 0.5) solders under 250 °C has been investigated. It was found that the poor oxidation resistance of the solders is attributed to the oxidation of Zn–rich phase and other Zn atoms which diffused to the β-Sn matrix grain boundaries which form ZnO. With Cr...

We prepared Pb(Yb1/2Nb1/2)0.10(Zr0.47Ti0.53)0.90O3 (PYN–PZT) piezoelectric ceramics of pure perovskite structure using the columbite precursor method with the addition of 0–0.8 wt% MnO2, and investigated in detail the effects of adding MnO2 on the sinterability, structure, and electrical properties of PYN–PZT ceramics. With a small addition of MnO2...

Based on hydrothermally treated phosphosilicate (SiO2–P2O5) glass and sulfonated poly(ether ether ketone) (SPEEK) polymer, perfluorosulfonate-free SiO2–P2O5/SPEEK composite membranes are prepared. The morphology, thermal and mechanical properties, pore structure, proton conductivity, water uptake, as well as the fuel cell performances of the SiO2–P...

The oxidation failure of a copper alloy lead frame with/without a copper plating layer was investigated. The oxidation rate and adhesion strength of oxide films on copper alloy substrates were studied by measuring the thickness and by carrying out peel tests. The adhesion strength of the oxide film was mainly influenced by the composition but not t...

An ideal low temperature bonding method was studied. Cu cones were prepared by electroless plating. Heating and pressure were used in the bonding process between Cu cones and Sn-3.0Ag-0.5Cu solder. It's a solid state bonding method because the bonding process was performed below the melting point of solder. Shear strength was measured by bonding te...

A simple method to increase the adhesion strength between leadframe and epoxy molding compound (EMC) was reported in this paper. Cone-structured copper film was deposited on copper-based leadframe sheets by electroless plating. SEM observation of the as-prepared film indicates that cone size distinctly depends on plating time. Adhesion strength bet...

Levelers have great influence on residual stress of electrodeposited film used in TSV. In this study, 2-MP (2-mercaptopyridine), JGB (Janus green B) and 2-ABT (2-aminobenzothiazole) are used as levelers to study the effects of different levelers on residual stress. The film stress deposited with different levelers decreases in the order of 2-MP, JG...

In this paper, the Sn-3.5Ag solder bumps were prepared successfully by two-step electroplating method. The effect of reflow time on shear property of solder bumps and Cu was investigated. After shear tests, the shear strength of Sn-3.5Ag solder bumps peaked at the reflow time of 60s, and then decreased with further increasing reflow time. It was co...

Photovoltaic (PV) ribbon is one of the PV cell assembly components used to connect cells to form a PV array working at proper current and voltage. It is a copper ribbon coated with tin-lead or lead-free solders, which provide solderable areas to form solder joints and protect the copper ribbon surface from oxidization. Tin-lead solder has been wide...

H2/O2 fuel cells equipped with proton-conducting Nafion®/phosphosilicate (NPS) glass membranes, which are prepared from phosphosilicate glass and a perfluorosulfonic acid polymer, are characterized, and their performances are improved step by step by using Nafion® resin as an adhesive, increasing operation temperature, adopting a thin-film pressure...

In this paper, the effect of trace addition of Cr on the mechanical properties and reliability on Sn–8Zn–3Bi solder alloys was investigated. It has been demonstrated that the microstructure of solder alloys was refined after doping traces of Cr. The elongation reaches up to 40.63% after doping 0.1% Cr; and the fracture mechanism converts from quasi...

In this work, a superhydrophobic nickel surface is fabricated by coupling electro and electroless deposition without chemical modification. SEM study reveals that electrodeposited nickel surface is characterized by nanocone arrays and has a contact angle of about 135°. After adding electroless deposition, as the second step, hemispherically topped...

The weak adhesion between the Epoxy Molding Compound (EMC) and Pd Preplated leadframes (Pd PPF’s) often causes delaminations and reduces the reliability of integrated circuit. This paper reports on a practical method of dramatically improving the adhesion between EMC and Pd PPF’s using electroplating of shaped nickel layers. Button shear tests indi...

Electronic assembly technology is in the transition from traditional tin-lead to lead-free. In comparison with Sn-Pb solders, high melting point and poor wettability of the lead-free solders lead to great challenge to present electronic assembly technologies. Inert nitrogen atmosphere can both widen the process window of reflow and improve the mech...

Co-Ni films are widely used in electronics industry for their excellent magnetic, mechanical and electrical properties. In this work, the influence of substrate type and deposition parameters on the morphologies of electroplating Co-Ni nanostructures was investigated. It was found that scallop shell-like Co-Ni depositions could be fabricated on cop...

In this study, an electroplating method to deposited Ni, crystalline NiW(c-NiW), amorphous NiW (a-NiW) films on P-type Si(1 0 0) were used to form Ni-silicide (NiSi) films. After annealed at various temperatures, sheet resistance of Ni/Cu, c-NiW/Cu and a-NiW/Cu was measured to observe the performance of those diffusion barrier layers. With W added...

Low cost electrodeposited Sn3.5Ag solder bumps fabrication technology was developed for three-dimensional packaging applications. Effect of reflow time on interfacial reaction of electroplated Sn3.5Ag solder bumps with Cu under-bump metallization (UBM) was investigated. The microstructure of eutectic Sn3.5Ag is composed of β-Sn phase and Ag3Sn IMCs...

The effect of polyethylene glycols upon copper electrodeposition in methanesulfonate electrolytes is discussed in this paper. By means of linear sweep voltammetry and electrochemical impedance spectroscopy, it is found that polyethylene glycols in methanesulfonat electrolytes have very different behavior from that in traditional sulfuric electrolyt...

Electroless Sn films have great potential in the lead-free age such as for high-density, fine-pitch, narrow soldering pad and bump interconnection applications. In the present work, electroless Sn were deposited onto lead-frame alloys (C194 and FeNi42). The microstructures of the electroless Sn films and tin whisker growth in thermal/humiditive cha...

In this study, we used electroless deposition of NiP, NiWP on p-type Si as the barrier layer to prevent the diffusion of Cu into Si. We added different amount of W into the layer, wt% is 11.89% (NiWP-1) and 25.36% (NiWP-2). After annealed at various temperatures, thermal stability of the Si/Ni(W)P/Cu layers were evaluated by measuring the changes o...

The weak adhesion between the Epoxy Molding Compound (EMC) and Pd Preplated leadframes (Pd PPF's) often causes delaminations and reduces the reliability of integrated circuit. This paper reports on a practical method of dramatically improving the adhesion of EMC and Pd PPF's using electroplating shaped nickel layers. Button shear tests indicate tha...

The oxidation behavior of Sn-9Zn-3Bi-xCr(x=0, 0.1, 0.3, 0.5) solders under 250°C has been investigated as a function of exposure time. The evolution of surface and cross-sectional microstructure has been examined through back-scattered electron detector (BSE). Energy-dispersive x-ray spectroscopy (EDX) and x-ray diffractometer analysis (XRD) were a...

Global escalating demand for energy is opening up the opportunities for utilization of solar energy, while photovoltaic (PV) cell is considered as one of the finest ways to harness the solar power. PV ribbon, which is a copper ribbon coated with tin-lead or lead-free solders, is one of the key PV cell components to connect cells. In this paper, ten...

Moisture ingression in plastic packages generally occurs through delaminated interfaces between different materials. So the adhesion strength between molding compound and substrate is crucial to the plastic package reliability. In the present work, a sample preparation device was designed for molding compound adhesion test. A series of experiments...

Molded interconnect system (MIS) is a new generation of substrate technology for traditional QFN, and fine gold wire bonding should be used. While lots of studies focused on the wedge bonding process, the effect of Ni/Pd/Au finish on the bonding force was never verified before. This paper will present a detailed investigation on the wedge bonding o...

Electrochemical corrosion behaviors of Sn-9Zn-3Bi-xCr solder in 3.5 wt.% NaCl solution were investigated in this work through potentiodynamic polarization measurements. After electrochemical testing, fracture surfaces were investigated by scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffractometry. The results show...

Self-organized Ni–Ti–O nanotube arrays were fabricated through a direct anodization of NiTi shape memory alloy in glycerol-based electrolyte. The growth of Ni-doped TiO2 nanotube arrays was mainly affected by anodization voltage and temperature. Higher anodization voltage facilitated the growth of uniform nanotube arrays. Large-area open-ended Ni–T...

Intermetallic compounds (IMCs) growth on the Sn–8Zn–3Bi (–Cr) solder joints with Cu and electroplated Ni substrates was investigated after aging at 150°C. It was found that the IMCs were the Cu5Zn8 and Ni5Zn21 at the solder/Cu and solder/Ni interface, respectively. The IMCs growth rate at the Sn–8Zn–3Bi–Cr/Cu and Ni interface was slower than that a...

In this paper, the effect of sputtering parameters on the interfacial reaction and the electronic properties of the WNx system were reported. The report showed that W and W2 N phases were observed in WNx film on GaAs substrate annealed at 800–900°C, in which no UN phase was found and W2N was the stable phase. Throughout the WNx film, W,N distribute...

The effect of Zn addition on the microstructure, tensile properties and electrochemical properties of as-annealed 3003 Al alloy was investigated through TEM observations, tensile tests and Tafel polarization analysis. High density precipitates are observed in the Zn-containing alloys and the alloy with 1.8% Zn addition also has rod-like precipitate...

A metallic nanocone array by means of a directional electrodeposition method without any template is reported. With the crystallization modifier in the nickelelectroplating solution, the cobalt conical structure can be deposited onto different metal substrates. The morphology of the nanocones can be controlled by changing the electroplating conditi...

Copper electrodeposited on nickel and copper alloys substrates is easy to be oxidized, and the adhesion between the oxides and substrates can be so poor that delamination happens at these interfaces, which may lead to an overall failure to the electronic device. In this work, three different substrates were prepared by applying direct current; of a...

Electroplating matte Sn has attracted much attention in the lead-free age. To prevent a growth of tin whiskers from lead-frame supported matte tin films, various mitigation methods have been reported. In this work, pure matte Sn was electroplated onto C194 alloy, and electroplating Ni film was used as barrier between matte Sn and lead-frame alloy....

There are many factors which will affect the final result of TSV filling, such as ratio of the additives including accelerator, suppresser, leveler and so on. Complicated environment is also hard to control exactly. If we want to form the “bottom up” in the plating, there must be comprehensively consideration of all factors. Many studies have focus...

The microstructual stability of Sn-8Zn-3Bi/Cu and Sn-8Zn-3Bi-0.3Cr/Cu joints has been investigated under 85 °C temperature and 85% humidity conditions as a function of exposure time. The evolution of interface and near surface cross-sectional microstructures during exposure has been examined. A continuous single layer of intermetallic compound (IMC...

Electroplating metallization method for crystalline silicon solar cell was investigated with new diffusion barrier layer, Ni, crystalline NiW (c-NiW), amorphous NiW (a-NiW). After annealed at various temperatures, sheet resistance of Ni/Cu, c-NiW/Cu and a-NiW/Cu was measured to observe the Cu diffusion barrier performance. The rapid increase in she...

In this paper, the effect of 0.1wt.% Cr addition into Sn–9Zn lead-free solder alloys on the growth of intermetallic compound (IMC) with Cu substrate during soldering and subsequent isothermal aging was investigated. During soldering, it was found that 0.1wt.% Cr addition did not contribute to forming the IMC, which was verified as the same phase st...

This paper reports the photoluminescence and afterglow behavior of Eu2+ and Eu3+ in Sr3Al2O6 matrix co-doped with Dy3+. The samples containing Eu2+ and Eu3+ were prepared via solid-state reaction. X-ray diffraction (XRD), photo luminescent spectroscope (PLS) and thermal luminescent spectroscope (TLS) were employed to characterize the phosphors. The...

Super-hydrophobic nickel films were prepared by a simple and low cost electrodepositing method. The surface morphologies of the films characterized by scanning electronic microscope exhibit hierarchical structure with micro-nanocones array, which can be responsible for their super-hydrophobic characteristic (water contact angle over 150°) without c...

We report uniform anodization of biphase Ti35Nb5Zr alloy to form doped nanotube arrays in nonaqueous glycerol-based electrolytes rather than in traditional aqueous electrolytes. The electrolyte type played an important role in determining the formation of uniform nanotube arrays. Through using the glycerol-based electrolytes, phase-dependent anodiz...

The optimum nucleating agent had been investigated in Li2O–Al2O3–SiO2 glass–ceramics system with 2% ZrO2 and different amounts of TiO2 as nucleating agents. The activation energy (E) of crystallization and the Avrami parameter (n) for the LAS glasses obtained from the DTA and results show that the most effective addition of TiO2 was about 2.36wt.%....

TiO₂ nanotubes have wide applications in gas sensing applications such as oxygen sensors and hydrogen sensors. In this work, crystallized TiO₂ nanotubes self-assembled on Ti substrate were fabricated through anodization and heat-treatment. The anodization parameters for fabricating optimized nanostructures were investigated an...

Though silicon vias filled by pulse reversal current, and influences of frequency of pulse current and reverse current density are investigated. Chronopotentiometry was applied to analyze the principle of these effects. It was found that when frequency is too high, the reverse current was mainly consumed in process of charge-discharge of electric d...

Copper electrodeposition in acidic cupric methanesulfonate bath with organic additives is discussed in this paper. The influence of poly(ethylene glycol) (PEG) and bis-(3-sodiumsulfopropyl disulfide) (SPS) on copper deposition were studied by means of linear sweep voltammetry, cyclic voltammetry and chronoamperometry. These electrochemical analysis...

Deep via filling is one of key technologies of 3D packaging. Vias are commonly filled by electroplating. Since cupric transportation in vias is limited by diffusion, Current density is one of the most influential factors for copper plating in vias. We investigated new additive of accelerator, suppressor and leveler. Simulation of the competitive ad...

Nano-coned array of Cu were prepared by electroless plating with special crystallization conditioning agent. The morphologies of nano-coned array were observed by FE-SEM. The influences of active time in PdCl2, concentration of NiSO4middot6H2O, crystallization conditioning agent, pH and temperature of plating solution were discussed. Then, the poss...

Electroplating Sn plays an important role in the lead-free age because of its excellent solderability and many other advantages. In this work, bright Sn was electroplated onto both C194 and FeNi42 alloys. The plating parameters, substrate effect, barrier layer effect and IMC formation were investigated through detailed microstructural characterizat...

Through silicon via technology is one of the critical and enabling technologies for 3D packaging. 300 mum deep vias with a diameter of 50 mum were filled by copper electroplating with CuSO4 and H2SO4 as base electrolyte. Chloride ions, accelerator and leveler were added. The effect of leveler concentration on filling performance was studied. Electr...

Three-dimensional packaging technology, which requires fine pitch and high density of solder bumps, has been developed recently for system-in-package applications. There are several methods being used for solder bumping process for now. As the sphere pitch decreases to below 100 mum, electrodepositing has an advantage over robotic ball placement an...

This paper has explored the using of Cr micro-alloying method to enhance the corrosion resistance of Sn-Zn-Bi alloy. In addition, the influence of long-term aging on solder corrosion resistance has been studied. The electrochemical corrosion behaviour of Sn-8Zn-3Bi-XCr solder in 3.5% NaCl solution was investigated by using potentiodynamic polarizat...

Super-hydrophobic Nickel films were prepared by a simple and low cost electrodeposition method. The surface morphology of the films characterized by FE-SEM exhibit hierarchical structure with micro-nano cones array, which can be responsible for their super-hydrophobic characteristic (water contact angle is over 120 degree) without any chemical modi...

This work reports on the wetting behavior of electrolyte in fine pitch Cu/Sn bumping process by electroplating. Three methods containing adding complex wetting agent to electrolyte, plasma treatment to photo-resist and ultrasonic vibration were taken to improve the wettability between electrolyte and related materials. Contact angles of electrolyte...

In this paper, Traces of Cr were added into Sn-8Zn-3Bi solder alloys to study the influences of Cr on mechanical properties and high temperature reliability of solder alloys by room temperature tensile test and high-temperature aging treatment. With observation of microstructure and fracture surface analysis, the strengthening mechanisms of Cr in s...

We report anodic formation of Ti-Nb-O nanotubes on top of a Ti35Nb alloy, and in vitro bioactivity and stem cell response of the anodic nanotubes. It was found that the amorphous Ti-Nb-O nanotubes presented a significantly enhanced in vitro bioactivity (in simulated body fluids) compared to those of undoped TiO2 nanotubes and porous Ti-Nb-O without...

We report an alternative hydrothermal process for the preparation of pure phase LiCoO(2) cathode material for potential application under high rates. By adjusting the hydrothermal conditions, nanoplate-like LiCoO(2) crystals were obtained, with grain size about 200 nm. It was found in the experiment that the H(2)O(2) concentration and hydrothermal...

This paper reports the preparation of long persistent Sr2Al2SiO7:Eu2+ and Sr2Al2SiO7:Eu2+, Dy3+ phosphors and the comparison of their photoluminescent properties. The silicate phosphors prepared by solid-state reaction routine showed a broad blue emission peaking at 484 nm when activated by UV illumination. Such a bluish-green emission can be attri...

The influences of crystal orientation on copper oxidation were investigated. The results indicated that crystal orientation of copper substrate has a great effect on the growth rate, the morphology of oxide film and the extent of oxidation failure. Shear test showed the adhesion strength between Cu(110) and its oxide film was the highest, whereas,...

This work investigates the thermal stability and in vitro bioactivity of Ti-Al-V-O nanostructures grown on Ti6Al4V alloy through an anodization method. After anodization of the two-phase Ti6Al4V alloy, there were two different kinds of Ti-Al-V-O nanostructure (nanotube arrays grown in the alpha-phase region and irregular nanopores grown in the beta...

Oxidation of four typical lead frame copper alloys was investigated. The oxidation rate and adhesion strength of oxide films to copper alloy substrates were studied by measuring the thickness and carrying out peel tests. The results show that, although copper alloys C5191 and C7025 have thinner oxide films, a lower adhesion strength and a higher pr...

Influence of Cr on growth of interfacial intermetallic compound (IMC) at the interface of Sn–9Zn/Cu substrate during aging at 85°C/20%RH and 85°C/85%RH for 500h has been investigated. After aging treatment, IMC layer at the Sn–9Zn/Cu joint is much thicker than that at the Sn–9Zn–Cr/Cu joint. Estimation according to experimental data presents that I...

This paper reports a simple one-step hydrothermal routine to prepare orthorhombic LiMnO2 powder for Li ion battery application. Employing Mn2O3 and LiOH as the starting materials, hydrothermal reaction operated under 160 °C for 12 h generated pure-phased o-LiMnO2 powder. The morphological change and reduction in grain size between the reagent and t...

This paper reports a novel hydrothermal method to synthesize nanorod like Gd2O2S:Eu,Ti,Mg persistent phosphor and the characterization of the same. Hydrothermally prepared Gd(OH)3 nanorod precursor, codoped with Eu, Ti and Mg, was converted into the aimed phosphor by calcinating the precursor in CS2 atmosphere. XRD investigation revealed a pure pha...

The interfacial reaction between OSP, electrolytic Ni/Au, and electroless Ni/Pd/Au surface finish and SnAgCu solder on BGA package were investigated. After multiple reflows, IMC morphology and composition is examined by SEM and EDX. Cu₆Sn₅ formed between LF35 and OSP finish, and Ag₃Sn were found disperse in the sold...

Co-Ni alloys have the properties of high hardness, good wear and corrosion resistance. A transition layer of Co-Ni coating will help enhance the hydrogen sensing stability of Pd films. In this work, Pd films were electrodeposited on Co-Ni coated copper substrate and silicon wafers. The influence of deposition parameters on the microstructure of Co-...

This work reports on the fabrication and thermal stability of self-organized titania nanostructures on Ti6Al4V alloy. Ti6Al4V sheets were anodized in 1M NaH 2 PO 4 containing 0.5 wt% HF. And the anodized sheets were heat-treated at different temperatures to test their thermal stability. SEM observations revealed that, for the two-phase Ti6Al4V allo...

In this paper, a novel low-temperature micro-insert bonding technology for 3D package has been reported. Nickel microcone arrays (MCA) fabricated on the bonding pad was used as the under bump metallization (UBM). The bonding temperature is below the melting point of the solder. At certain temperature and pressure, the MCA inserted into the lead-fre...

Li2O–Al2O3–SiO2 glass with CaO, MgO and TiO2 additive were investigated. With more CaO + MgO addition, the crystallization temperature (Tp) and the value of Avrami constant (n) decreased, the activation energy (E) increased. The mechanism of crystallization of the glass ceramics changed from bulk crystallization to surface crystallization. With mor...

The influences of different Cr content to lead (Sn)–Zn solder were investigated. Sn–9Zn–xCr shows finer and more uniform microstructure than Sn–9Zn. Thermal gravimetric analysis (TGA) and Auger electron spectroscopy (AES) results show that adding Cr significantly improves the oxidation resistance of Sn–9Zn solder, and reduces the thickness of oxida...

The peeling resistances of oxide film formed on copper alloy lead frames with and without pre-heat treatment were investigated. With the increase of the heat treatment temperature, the peeling resistances of oxide film of C194 decrease, while C7025 show little variances in contrast. Crystal orientation of copper alloy with and without heat treatmen...

In this paper, the interfacial reactions of Sn-8Zn-3Bi and Sn-8Zn-3Bi-0.3Cr solders with Cu pads and the growth of IMCs during long-term aging treatment were presented and discussed. Less than 3 mum Cu5Zn8 IMC layer was found at the Sn-8Zn-3Bi-(0.3)Cr/Cu during the reflow at 230degC for 1 min. During solid state aging treatment at 150degC for 4, 9,...

The effect of crystal orientation on the oxidation failure of pure copper was investigated. XRD results indicated that the oxide film grown on copper surface was mainly composed of Cu2O. The adhesion strength between Cu(110) and its oxidization film was the highest, whereas, the adhesion strength between Cu (311) and its oxidization film was the lo...

This paper reports a hydrothermal conversion process of a rare earth nanostructure, Gd(OH)3 nanorods, into photoluminescent GdVO4 nanorods, together with the investigation on the morphological changes and related photoluminescent properties. Gd(OH)3 precursor with nanorod shape, uniform diameter, and good crystallinity was prepared by a colloidal h...

Tartaric acid method was introduced to fabricate BiFeO3 ceramics and Re-doped (Re = La, Nd) BiFeO3 ceramics. The X-ray diffraction revealed that after 2 h of calcination at 500°C, the precursors were all turned into pure Bi1-xRexFeO3 powder. The parameter of Bi1-xRexFeO3 unit cell became smaller with the increase of dopant. The formation of impure...

Wollastonite (CaSiO3) ceramics were prepared by a new sintering technology: spark plasma sintering (SPS), using CaSiO3 ultra-fine powders as precursor. The ceramics were sintered at different temperature and different heating rate. The properties of sintered ceramics were discussed detail. All samples have a high relative density, which are close t...

This work reports the synthesis of Ni nanocones by a one-step electrodeposition method without any template. With the addition of ethylenediamine dihydrochloride (EDA2HCl) in the nickel plating solution, the novel Ni conical structure can be easily deposited onto different metal surfaces. The as-prepared nickel nanocones grow preferentially along d...

This paper reports the detailed preparation process and afterglow properties of Eu3+ activated long lasting Gd2O2S phosphor by hydrothermal routine. Rod-like Gd(OH)3 were firstly synthesized by hydrothermal method to serve as the precursor. Long lasting Gd2O2S:Eu3+,Ti4+,Mg2+ phosphor was obtained by calcinating the precursor with co-activators and...

TiO(2)/Al(2)O(3) stacked high k dielectric films were deposited by RF-magneton sputtering. The effect of post-anneal on the morphology, equivalent oxide thickness, fixed charge density and the interfacial diffusion of the films were studied by atomic force microscopy, X ray diffraction, precise impedance analyzer, picoammeter and Auger electron spe...

This paper reports a hydrothermal conversion of MnOOH needles into orthorhombic LiMnO2 nanorods for lithium ion battery application. XRD investigation indicated phase conversion during the Li ion incorporation, and several intermediate phases were formed during the hydrothermal reaction. SEM observation of the sample powder revealed morphological c...

Crystallization, morphology and mechanical properties of a spodumene-diopside glass ceramics with adding different amount of CaO and MgO in Li2O-Al2O3-2SiO2 were investigated. With CaO and MgO addition, the crystallization temperature (T p) decreased, the value of Avrami constant (n) decreased from 3.2±0.3 to 1.4±0.2, the activation energy (E) incr...

Ni nanocones field emission arrays (FEAs) were fabricated by electro deposition. Morphologies of the Ni nanocone arrays were investigated by scanning electron microscope (SEM). Field emission properties of these arrays were tested by a vacuum field emission measurement system. The Ni nanocone arrays had low turn-on fields of 5-6.7 V/mum (correspond...

A transition layer of Ni-P coating will help enhance the hydrogen sensing stability of Pd films supported by silicon wafers. In this work, Pd films were electrodeposited on electroless Ni-P coated silicon wafers. The effect of deposition parameters on the microstructure (especially the morphology) of Ni-P coatings and Pd films were investigated. Ex...

The influence of different Cr content on oxidation resistance, thermal properties, wetting properties, growth of intermetallic compound of Sn-9Zn-3Bi based solder are described herein, and compare with eutectic Sn-9Zn solder. Cr element segregates in the near-surface layer, and improves the oxidation resistance which contributes to better wettabili...

Microcones arrays of cobalt were prepared by electrodeposition with special crystallization conditioning agent. The influence of electrodepositing conditions and form factor effect on the morphology of microcones array is reported. X-ray diffraction result indicated that the Co arrays growing with (110) preferred orientation. The Co array had an ob...

Concentrations of 0.1. 0.3. and 0.5 wt.% of Cr were added to Sn-3Ag-3Bi alloy to produce Sn-Ag-Bi-Cr alloys. The microstmcture is refined with Cr additions, while significantly improves the oxidation resistance. There is no change in the wettability and liquidus temperature after Cr additions. In addition, the effect of Cr addition on the intermeta...

Lhe influences of adding 0.05, 0.1, 0.3, 0.5 wt.% Cr to Sn-9Zn alloy on growth of intermetallic compound layer (IMCs) at the interface of Sn-9Zn-xCr/Cu was investigated during aging treatment at 85degC and relative humidity from 20% to 85% for 100 h, 200 h, 350 h, 500 h. Lhe results show that IMCs thickness of Sn-9Zn-Cr alloys is much thinner than...

Single-crystalline CaSiO3 nanobelts were prepared via a simple solvothermal routine. The synthesized material revealed bioactive response when immersed in a simulated body fluid (SBF) solution, suggesting its potential application as biomedical materials.

Influence of surface electroplated pure copper on oxidation failure of lead frame copper alloys for IC package were investigate. Pure copper layer will benefit the diffusion of copper ion, so the thickness of copper oxide films increase but the velocity of CuO formation decrease and the oxidation only occurs at pure copper layer. As electroplating...

The platelike bainitic ferrite growth rates in different alloy content steels were calculated by Zener-Hillert and Bosze-Trivedi models after optimization of thermodynamic and kinetic parameters. Good agreements between experimental and theoretical results are found in Fe-0.59C, Fe-0.81C and Fe-0.478C-4.87Ni alloys. A slowing down effect due to the...

Nanocrystals of titanium-substituted hydroxyapatite (CTHAp) were prepared with Ti4+ concentrations of x=0, 0.1, 0.2 and 0.5 [x=Ti/(Ca+Ti)] at hydrothermal temperatures of 100, 150, 190 and 230°C. The effects of reaction temperature and titanium concentration on the crystal were investigated by using TEM, XRD, FTIR, ICP and XPS. The obtained CTHAp c...

The effects of surface electroplate pure copper on oxidation failure of lead frame copper alloys for IC package were investigated. Pure copper layer will benefit the diffusion of copper ion, so, the thickness of copper oxide films increases but the velocity of CuO formation decreases and the oxidation only occurs at pure copper layer. As the electr...

With the improvements on the chip integration density, providing effective heat removal solutions for CPU is an essential research project in the electronics industry. Taking aim at the problem caused by heat generation of CPU, this paper mainly discussed the current developments, principles of heat transfer and perspective applications of the thre...

Directional electrodepositing method was introduced originally to fabricate nickel nanocone array material, and the nucleation process of Ni nanocones was studied. The SEM results show that small nuclei quickly form at the very beginning of electrodepositing process. With the process going on, the grains grow much faster at lengthwise direction tha...

This paper reports the synthesis, characterization, and dehydration kinetics of a rare earth hydroxide, Gd(OH)3. Uniform rod-like Gd(OH)3 powder was prepared by a colloidal hydrothermal method. The powder thus obtained dehydrated into its oxide form in a two-step process, where crystalline GdOOH was obtained as the intermediate phase. Crystal struc...

Since Au is used as the end finish on Pd preplated leadframes (Pd PPFs), the weak adhesion between the surface noble metal Au and the epoxy molding compound (EMC) often causes delamination and reduces the reliability of integrated circuit (IC) packages, which greatly limits the application of Pd PPFs. This paper reports on a novel application of ar...