Plating Film Research Articles

Palladium composite membranes by electroless plating technique: Relationships between plating kinetics, film microstructure and membrane performance

Thin supported palladium membranes were prepared using electroless plating technique. The intrinsic plating kinetics were determined for hydrazine-based palladium plating baths. Mathematical models were developed to predict film thickness and plating rate as a function of plating parameters (i.e., reactant concentrations, temperature and time). Analyses of film surface microstructure indicate that grain structure is dependent on both plating chemistry and plating rate. The evolution of film morphology during electroless plating was also investigated. Hydrogen permeation study demonstrated that film structure has a significant influence on the permeation performance of the palladium membrane.

６‐ジアリルアミノ‐１，３，５‐トリアジン‐２，４‐ジチオールの有機めっきにおよぽすＮａＮＯ２の促進作用

Organic polymer plating properties of 6-diallylamino-1, 3, 5-triazine-2, 4-dithiol monosodium (DAN) were studied for NaNO2 supporting electrolytes. Supporting electrolytes cause polymer film to form or not. NaNO2 electrolytes particularly accelerated the formation rate of polymer plating. The accelerating effect of NaNO2 was confirmed comparing plating potentials in the presence of NaNO2 and NaCO3. NO2- anions are electrochemically oxidized to yield NO2·radicals that react with DAN to yield thiyl radicals. DAN thilyl radicals between molecules, yielding disulfide bonds that grows into polymer films. Organic polymer plating films contained disulfide and monosulfide bonds produced by the reaction between allyl groups and thiyl radicals and network chains.

パラジウムめっきリードフレームの曲げ特性に及ぼす下地ニッケルめっきの析出条件の影響

In the palladium plating leadframe, nickel and palladium are plated over the whole surface including outerleads in the leadframe manufacturing process. Users have pointed out plating film cracks after bending of outerleads. The most thickness of the plating film is nickel.We changed nickel plating conditions and studied the influence on plating film cracks, with the following results: (1) Nickel plating film from a sulfamate bath produces fewer cracks than that from a Watt's bath and is suitable for the underlayer of palladium plating film. (2) Internal stress in nickel plating film rises abruptly when the sulfamate bath pH exceeds 5.0. Even then, cracks did not grow larger, indicating no correlation between internal stress and crack extent. (3) Plating conditions should be monitored to maintain plating thickness because current efficiency changes with plating conditions. Their influence on cracks is small.

Effects of the alkaline permanganate etching of epoxy on the peel adhesion of electrolessly plated copper on a fibre-reinforced epoxy composite

The adhesion of electroplated copper to a fibre-reinforced epoxy composite is controlled by mechanical keying. Rough surfaces are prepared by chemical etching. Therefore mechanical properties could be degraded if the difference in reactivity of the composite components (fibres and matrix) is not taken into consideration. To eliminate this surface heterogeneity, a plating film (epoxy resin) is applied to the composite, which becomes chemically homogeneous. During the etching process, this plating film will protect the integrity of the composite. Later on, copper can be directly electroplated onto the intermediate layer (epoxy resin). This study describes the influence of the surface geometric characteristics of two composites on the adhesion strength of a copper coating. We have found that the mean peak-to-valley height (Rz) is not sufficient to explain the adhesion level. The technique of profilometric relocation is used for quantifying the etching effect on the surface micro-geometry, which is dependent on the initial composite substrate roughness.

ＢＧＡパッケージ用テープ基板における無電解金めっき厚さとワイヤボンディング性およびはんだボール接合性

Tape carriers have been used as BGA substrates because of their thin, fine circuits and high manufacturing accuracy. Electroless gold plating on tape carriers has become required. Electroless gold plating tape carriers having good gold wire bondability and ball solderability are being developed. We studied the influence of electroless gold plating thickness on wire bondability and ball solderability, with the following results: (1) The pull strength of gold wires on tape carriers with 0.2μm and over gold plating thickness was 0.07N or more. (2) The shear strength of solder balls on tape carriers with 0.2μm and below gold plating thickness was 3N or more after heat aging at 150°C for 500h. (3) Tape carriers with 0.2μm gold plating film had good wire bondability and ball solderability.

電析Ｆｅ‐Ｗ合金めっき膜の切削刃物への応用

Fe-W amorphous alloy films were prepared on an iron substrate by an electroplating method. The hardness of the heat-treated film was greater than 2, 000 (Hv/50g), according to the Vikers hardness test. By coating the surface of a conventional end-mill with this Fe-W plating film, a cutting tool with very high anti-wear properties can be obtained. This hardening mechanism may be explained by the changes in the crystallographic structure of the plated Fe-W alloy film. The structure changed from crystalline to amorphous as the concentration of W in the film increases. At W concentrations of above 50wt%, the film becomes amorphous. This concentration is in agreement the concentration of an intermetallic compound that become very hard by heat-treatment.

熱処理に伴う無電解ニッケル‐リン合金めっき皮膜の変色防止

熱処理に伴う無電解ニッケル‐リン合金めっき皮膜の変色防止

トルメチルアミンボランを還元剤とする無電解パラジウムめっき皮膜の結晶構造

This report describes the crystal structure of and heat-induced structural changes in electroless palladium plating films deposited from an ethylenediamine complex bath using trimethylamine borane as a reducing agent. The boron content of the films and their crystallinity were proportional to the concentration of trimethylamine borane in the bath. X-ray diffraction data showed a diffused pattern, in as-plated films (before heat-treatment), which changed into the sharp crystalline features of PdH0.706 at 400°C, and the sharp crystalline features of the Pd phase after heat-treatment at 600°C. The diffraction angle of the Pd phase shifted to a slightly lower angle following an increase in boron content.

スズめっきした無電解ニッケル‐リン合金めっき皮膜の耐食性

スズめっきした無電解ニッケル‐リン合金めっき皮膜の耐食性

Properties of Low-Resistivity Undoped indium-Oxide Films Grown by Reactive Ion Plating and Electrochromic Tungsten-Oxide Films Grown by Electron-Beam Evaporation

AbstractThe use of gaseous discharge for ion plating and related techniques have been well known to improve coating properties in several ways. IN the arc-induced ion plating (AIIP), the ionization efficiency for the evaporants is so enhanced without any introduction of inert gases that the bias voltage for, and the temperature of the substrate are reduced in the preparation of the coatings. Highly transparent (> 90% transmission in the visible range) and highly conductive (resistivity ≅ 1.5 x 10-4 Ω cm) in-oxide films were deposited at a rate of 500 - 900 Å/min by aIIP of pure in in an O2 atmosphere of 10-4 Torr. Hall-effect measurement revealed that the observed low resistivity is due primarily to the excellent electron mobilty (≥ 70 cm2 / V sec) with carrier density up to 7 х 1020/cm3. Electrochromic WO3 films were also prepared and characterized.

クエン酸系電析金めっき浴でのカチオン性高分子添加物の影響とその金めっき膜の耐食性： 高分子添加物の構造と機能の相関

The effects of cationic polymer additives on gold electrodeposition citric acid baths and the corrosion resistance of gold plating films were investigated by physicochemical methods. In a bath containing a small amount (5ppm) of poly (ethyleneimine) derivative such as ethoxy-modified (PEIEt), film porosity decreased significantly and deposition efficiency decreased slightly. The lower film porosity in the bath with PEIEt is due to the fine structure of grain and the leveling effect of surface. In polymer additives such as PEIEt, the effective property given the lower film porosity and higher deposition efficiency can be obtained by the balance between continuous adsorption ability and steric hindrance of polymer.

クエン酸系電析金めっき浴での有機添加物およびパルスめっき法の相乗効果とその金めっき膜の耐食性 添加物構造と膜耐食性の相関

The synergistic effect of organic additives and pulse-current plating in a gold electrodeposition citric acid bath was investigated. Then the corrosion resistance of the gold plating film was evaluated by physicochemical methods. By the synergistic effect, the bath containing 2, 3-diaminopyridine (23DAmPy) produced both lower film porosity and higher gold deposition efficiency. These properties are due to the moderate physical adsorption of 23-DAmPy, whose structure is susceptible to cation, under pulse-current plating. In any event, the synergistic effect appears in pulse-current plating in the bath containing organic additive.

ウエットプロセスから見ためっき皮膜の密着性

ウエットプロセスから見ためっき皮膜の密着性

置換すずめっき処理によるはんだめっきの改質

The solder plating posttreatment we developed involved immersing the plating film in a tin fluoborate solution and substituting tin for lead as follows:Sn2+(L)+Pb(s) High temp._??_Low temp.Sn(s)+Pb2+(L)where (L) indicates “in solution” and (s) indicates “in solder film”. Increasing the concentration of Sn2+ and the temperature reversed the redox potentials, M2++2e_??_M, toward less noble Sn making the forward reaction dominant.This treatment produced a smooth surface lustrous and enriched in tin content in the outer portions of the film. This resulted in a marked inprovement in antioxidation properties, adhesion to the basis metal, solderability, and heat-humidity stability.Enriched lead in the bath due to the multitreatment was easily removed as PbSO4 precipitate by adding sulfric acid.

ワット浴より電析されたNi膜の微細構造

The cross-sectional microstructure of the Ni film electroplated from a Watts type bath was observed by transmission electron microscopy in detail and the formation process of a layered structure which had been observed sometimes in the cross-section of the film was discussed. It was found that the layered structure is the alternate structure of large crystal layers and small crystal layers. The reason for the formation of the layered structure is related to the bubbles of hydrogen evoluted at higher current density plating. Namely, when the evoluted hydrogen bubbles rise along the cathode surface, a diffusion layer on the cathode surface is agitated by the bubbles, and then the Ni atoms are deposited and plating is carried out without existence of a diffusion layer. At this time, the large crystal layer is formed. But, after a short time, the diffusion layer is formed again and the deposition of atoms takes place through the diffusion layer. At this time the small crystal layer is formed. The formation of the layered structure observed in the cross-section of the Ni plating film results from alternate occurrence of this behavior in accordance with the chemical reaction change on the Ni plating.The crystallographic relationship between the deposited Ni film and the Cu substrate is also discussed.

Effect of Poly(ethyleneimine) Derivative Additives in the Gold Electrodeposition Acid Bath and the Corrosion Resistance of Gold Plating Film.

Effect of Poly(ethyleneimine) Derivative Additives in the Gold Electrodeposition Acid Bath and the Corrosion Resistance of Gold Plating Film.

ＡｕめっきＣｕ複合ワイヤの超音波ボンディング

Ultrasonic bonding of Cu composite wire with Au coating at room temperature has been investigat-ed for packaging technique of thin film device unaccepted heating. Cu composite wire used in this study consists of Cu core of 44μm in diameter and Au coating of 3pm in thickness. Two kinds of bonding pads are used. One is Au plating film of 5-6μm in thickness on Au/Cu/Cr thin film deposited by sputtering on Cu substrate. Another is Au PVD film of 0.4μm in thickness on Cu/Cr thin film deposited on Cu substrate. Specimen has been bonded under the conditions of various ultrasonic power, bonding load and bonding time. For evaluation of a bonded specimen, the wire deformation and the 90 pull strength have been measured, and fracture surface has been observed by SEM. Main results in this study are as follows;(1) Adhesion and rupture take place alternately and periodically during ultrasonic bonding of Cu composite wire with Au coating. Then the joint strength also increases and decreases according to those. This phenomena is more remarkable on the bonding condition of a lower load and an upper US power, and the periodic time is shorter on that of an upper load and US power.(2) If a wire deformation ratio of squeezing size to initial diameter of wire, is controlled in the range of 40 to 60 percent, the joint strength is obtained more than 0.3 N for Cu composite wire of 50μm in diameter.

Synergistic Effect of Organic Additives and Pulse-Current Plating in a Gold Electrodeposition Acid Bath and Gold Plating Film Corrosion Resistance.

Synergistic Effect of Organic Additives and Pulse-Current Plating in a Gold Electrodeposition Acid Bath and Gold Plating Film Corrosion Resistance.

熱拡散法により作製した光沢スズ‐ニッケル合金皮膜の構造と物性

After nickel plating on copper substrates and tin plating on top of that, the effects of heat treatment on crystal structure, contact resistance and hardness of the double plating films were investigated. X-ray diffraction measurements showed that heating the tin/nickel double plating films at 180°C for one hour resulted in the formation of tin-nickel intermetallic compounds.The contact resistance of the double plating films increased with increasing heat treatment time at 180°C, and showed higher contact resistance than bright nickel films. In a humidity cabinet test at 60°C and 90 percent relative humidity, double plating films after heat treatment at 180°C for four hours showed lower contact resistance than did bright nickel films.The hardness of the double plating films was enhanced by heat treatment, and was greater than that of bright nickel films. The double plating films after heat treatment were similar in appearance to stainless steel, with a slightly pink color.

Strength evaluation and effect of graphite on strength of electroless nickel plating on cast iron

The effect of graphite on the strength of electroless nickel plating on cast iron was studied. Specimens of cast irons with four types of graphite and of 0.4% carbon steel were prepared and machined into plates with dimensions of 10 mm × 3 mm × 80 mm. Electroless nickel plating, about 40 μm thick, was deposited on the test pieces. The plated test pieces were tested by three-point bending tests using both acoustic emission (AE) and microscopic observation to evaluate the strength of the plating film. It was found that the first AE signal was generated when the cracks initiated and the final AE signal was generated when the film was fractured by crack penetration into the film. In addition it was found that film cracks on cast iron were initiated by the graphite existing at the interface between the plating film and the substrate, and propagated to the surface of the film, unlike carbon steel. The strength of the plating film on cast iron measured by this method, decreased more sharply with increasing amount of graphite than with graphite shape. Observations of cast iron surfaces at early stages of plating showed that the nickel was deposited only on the matrix and not on the graphite. It is believed that the non-deposited areas of the cast iron acted as types of defects. It is concluded that the strength of electroless nickel plating film on cast iron is strongly influenced by graphite on the surface.