Nickel Sulfamate Bath Research Articles

電析ニッケルマイクロプローブの形状制御に及ぼす添加剤構造の影響

The shape of electrodeposited nickel microprobes changed from a flat to an oval shape with the addition of propargyl alcohol in a nickel sulfamate bath ; propargyl alcohol is considered to have the function of the shape control. To research the effect of this organic additive on the function of the shape control, several alcohols having different structures, that is, states of carbon to carbon bonding, numbers of hydroxyl groups bonded to the terminal carbon, and numbers of carbons in the molecule, were investigated.From the result of preparing nickel microprobes electrodeposited from the bath containing the additive, an alcohol with a carbon-to-carbon triple bond and hydroxyl groups was effective to control the shape, and an alcohol without a triple bond did not have the function of shape control.

Performance of Plasma-enhanced Sputter-deposited Nickel–3 wt% Vanadium Alloy Mask Cathode Electrode for Electroforming Nickel Thin Film Nozzle Plate of Piezo Ink-jet Printer Head*

A significant increase in the yield of electroformed nickel nozzle plates of piezo ink-jet printer heads was realized by (1) plasma-enhanced sputter deposition of a nickel–3 wt% vanadium alloy cathode electrode onto a Si (100) substrate wafer maintained at 650°C (2) electroforming nickel nozzle plates on one side of a pre-patterned cathode electrode in a nickel sulfamate bath containing appropriate additives. The electroformed nozzle plates were easily peeled off from the cathode electrode while the cathode electrode adhered quite strongly to the Si (100) wafer substrate. The successful fabrication of the nozzle plates was attributed to (1) compressive stress induced by argon plasmas impinging upon the cathode, (2) improved adhesion of the cathode onto the Si (100) wafer substrate by probable formation at 650°C of a nonmetallic compound, e.g., nickel silicide at the cathode/substrate wafer interface, and (3) proper selection and control of the most suitable electroforming condition which enabled linear correlation of current densities and compressive stress levels in the electroformed substrate wafers, thereby enabling a wider range of current densities for mass-production of nozzle plates.

Effects of boric acid on hydrogen evolution and internal stress in films deposited from a nickel sulfamate bath

The effects of boric acid additions on the pH close to the electrode surface, on the hydrogen evolution reaction and on the internal stress in the plated films were studied for the high speed electroplating of nickel from a nickel sulfamate bath at a current density close to the nickel ion limiting current density. The study was carried out at 50 °C and pH 4.0 using a 1.55 M nickel sulfamate plating bath containing boric acid at concentrations ranging from 0 to 0.81 mol L−1. The variation of the internal strain in the plated nickel films was determined in situ using a resistance wire-type strain gauge fitted to the reverse side of the copper electrode substrate. The solution pH at a distance of 0.1 mm from the depositing nickel film was measured in situ using a miniature pH sensor assembly consisting of a thin wire-type antimony electrode and a Ag/AgCl/sat. KCl electrode housed in a thin Luggin capillary. The addition of boric acid was shown to effectively suppress the hydrogen evolution reaction at nickel electrodeposition rates (18.0 A dm−2) close to the limiting current density (~20 A dm−2). Consequently, the solution pH adjacent to the plating metal surface was maintained at a value close to that in the bulk solution and the development of high internal stresses in the deposited nickel films was avoided.

2817 シリコンインゴット切断用電着ワイヤ工具の高速製造法の開発

An electroplated slicing wire with diamond abrasives is demanded for silicon wafer making process because of its long tool life and high productivity. Although It has a serious problem for its production that the electroplating rate in conventional method is generally very low under 1μm/min. Therefore brush plating method which is one of the high speed plating techbiques has been tried to apply for the wire production. After various kinds of the modifications and tests to fit for wire production, next results were identified. : (1) Nickel sulfamate bath is the most suitable for brush plating. (2) Manufacturing time could be shortened by higher current density in this plating process than that in the conventional. (3) Quality of plating depends on maximum current density of circuit and revolution of brushing wheel. (4) Density of plated abrasives on a wire depends on revolution and felt brush structure of brushing wheel. (5) The wire by this plating method has higher slicing performance than a conventional one.

ニッケル電析抑制機能に及ぼすプロパギルアルコールの拡散速度，被覆率および還元速度の影響

The inhibiting function of propargyl alcohol in nickel electrodeposition was studied by observing the cathodic polarization curves on nickel RDE in nickel sulfamate baths. The behavior of propargyl alcohol inhibiting the electrodeposition was analyzed based on the diffusion-adsorption-reduction model. The variations of the diffusion rate, the interfacial concentration and the coverage of propargyl alcohol with the electrode potential were simulated based on the reduction rate estimated from the model and the experimental results. The results of the simulation explained the experimental results well. Such a simulation gives useful information on the investigation of the additive behavior and the current distribution in the electrodeposition onto a micropatterned substrate.

Kinetics of electroplating process of nano-sized ceramic particle/Ni composite

Ultra-fine Al 2O 3, ZrO 2 and SiC powders were co-deposited with Ni by electroplating from a nickel sulfamate bath. An electroplating additive Na 3Co(NO 2) 6 can promote the co-deposition of the SiC particles, but the Al 2O 3 and ZrO 2 particles can form composite layers without the assistance of the additive. It suggests that the complex ion Co(NO 2) 6 3− acts as a catalyst during the composite plating. The Guglielmi adsorption mechanism is applied to the electroplating of the ultra-fine SiC with Ni. The ultra-fine SiC particles are more difficult to co-deposit than the coarse SiC, and the rate determination step is controlled by the transferal process of loose adsorption to strong adsorption. The embedded SiC concentration can be increased either by increasing electrical current density or by raising the pH of the suspension to 5. The existence of second ceramic phases in the co-deposited layer changes the grain shape of Ni from columnar to equiaxial, and reduces the average grain size of Ni-matrix to 50 nm.

A study on the mechanism of formation of electrocodeposited Ni–diamond coatings

Co-deposition behavior of diamond particles and nickel onto a steel in nickel sulfamate baths has been investigated using both a rotating disc and wire geometries. Based on the zeta potential measurement and the change of diamond content of the deposits with electrical potential strength, diamond particles attracted to the cathode electrophoretically after adsorption of positive nickel ions. Results of polarization studies showed that since the rate of nickel deposition was controlled by both mass transfer of the nickel ions and electrochemical deposition, diamond content in nickel–diamond deposits decreased with increasing applied potential and stirring speed in the relatively high rotation speed ranges.

Influence of sonication of nickel plating in a nickel sulfamate bath

Influence of sonication of nickel plating in a nickel sulfamate bath

Effects of chloride, bromide and iodide ions on internal stress in films deposited during high speed nickel electroplating from a nickel sulfamate bath

The effects of chloride, bromide and iodide additions on the internal stress developed in nickel films deposited during high speed electroplating from nickel sulfamate baths operated close to the nickel ion limiting current density were investigated. The variations in internal strain in the films were detected in situ using a resistance wire-type strain gauge placed on the reverse side of the copper substrate. The film resistance on the as-plated electrodes was measured using an electronic current interrupter technique. The effects of chloride, bromide, and iodide additions could be classified into two groups: (a) chloride and bromide ions, and (b) iodide ions. For chloride and bromide additions over the concentration range of 0.1 to 0.5 M, the nickel deposits exhibited a block- and pyramid-like texture with a (200) crystal orientation. The internal tensile stress developed in 20 μm thick nickel films deposited in the presence of these two halides was as low as 140–170 MPa. Conversely, for additions of iodide, at iodide concentrations greater than 0.1 M the deposited nickel exhibited a fine granular texture of disordered crystal orientation. The internal tensile stress developed in 20 μm thick nickel films deposited from these latter baths tended to rise with increasing iodide concentration to values considerably higher than those observed at similar concentrations of NiCl2 or NiBr2.

Metal Distribution in Jet Plating

Jet plating is a high‐speed electroplating technique. Due to its special flow characteristics it can be used to localize the electrodeposition reaction on an unmasked cathode. In this process, a jet of plating solution is directed to a cathode surface, and electroplating is done by applying an electric field between the cathode and an anode located in the jet nozzle. The electric current travels along the jet stream to the cathode, and electrodeposition reaction takes places locally only on the area where the jet impinges on the cathode surface. The objective of this study is to find the metal thickness distribution on the cathode surface as a function of current density, electrolyte composition, electrolyte velocity, and nozzle height. Copper plating from an acidic copper sulfate bath and nickel plating from a Watts nickel bath and a nickel sulfamate bath were studied.

Study on Machining Characteristics of Wire Tool with Electrodeposited Diamond Grains.

At present, the demand of hard and brittle materials (e. g. silicon and ceramics) is increasing with the development of electronics technology. The ID-blade which is one of the mechanical processing, has been used mainly in slicing silicon ingots. However silicon ingots become large due to the continuing imprvement of productivity and diminishment of production cost. It is difficult to use the ID-blade in slicing a large-size silicon ingot. Therefore, a wire tool with electrodeposited diamond grains that can slice such a silicon ingot has attracted attention. In this paper, the wire tool with electrodeposited diamond grains is fabricated by means of a nickel sulfamate bath and a copper pyrophosphate bath. Machining characteristics are examined through a series of slicing experiments, and material strength of the diamond wire tool is examined through theoretical and experimental results. This paper also discusses diamond wire tool life.

ト石の製法について

A novel method was proposed for producing the grinding wheel with single layer abrasives. It consists of the process of dipping steel base plate in nickel sulfamate bath, in which abrasive particles are suspended, and then, firmly bonding the particles by electroplating.The process is so simple that any distribution densities and any depths of plated layer (in which abrasive particles are embedded) can readily be regulated.

抵抗線ヒズミ計によるニッケルメッキの電着応力の測定

Internal stress of electro-deposit was measured by electric resistance wire type strain-meter for the purpose of obtaining the deposit of low internal stress in nickel electroforming.Though this method had some points to be improved, was practically satisfactory to get absolute value as expected in nickel electroforming.(1) Extension stress is found in the deposit in nickel sulfamate bath, and the deposit of low internal stress is obtained under the condition for high hardness deposit.(2) Primary brightner generally reduces the internal stress of the deposit, but increases by adding sodium benzil napthalen sulfonate to the bath.(3) It is possible to reduce the internal stress to zero in nickel sulfamate bath including nickel chloride.(4) Some reagents of secondary brightner decrease the internal stress of deposit in proportion to the increase of other additional reagents.