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Electrodeposition has been studied by double potential step chronocoulometry. A method of data analysis has been developed which permits the determination of the electrical charge equivalent to the amount of methyl viologen radical cation present in the precipitate at the switching time. These values in turn were used to calculate the concentrations of methyl viologen radical cation and alkyl sulfate anion prevailing at the electrode surface (i.e., in the vicinity of the deposit and the electrode surface). It was found that the product of these surface concentrations is relatively constant for a range of surfactant concentrations and switching times. In this analysis, it was necessary to assume that the limiting value of the concentration of surfactant monomer equals the cmc when the total surfactant concentration is equal to or greater than the cmc. The concentration product is identified as a solubility product for the salt and the values were 16 X 10 to the -7, 4.8 X 10 to the -7, and 1.6 X 10 to the -7 M squared at 25 degrees C for decyl, undecyl, and dodecyl sulfates, respectively. It is concluded that during the growth of the precipitate, a dynamic equilibrium is maintained in which the concentrations of methyl viologen radical cation and surfactant anion are maintained close to the values dictated by the solubility product constant.

The magnetic properties and crystal structures of alpha-Fe and Fe21Ni79 nanowire arrays fabricated by ac electroforming into self-ordered nanosized pores in anodic aluminum oxide (AAO) are examined. The coercivity of alpha-Fe nanowires was found to be ~2.02 kOe and its squareness was ~0.9 whereas the coercivity of Fe21Ni79 was ~1.20 kOe and its squareness was found to be ~0.99.

Electrodeposition method was utilized in synthesizing composites with nanometer dimension copper particles in a silica gel medium. The diameters of the copper particles in the composites range from 3.2-11.4 nanometer. Using 110 to 300 K temperature, the electrical resistivity of the nanocomposite copper powders was measured. Results revealed that the resistivity was dependent on a temperature with a fractional exponent of 0.25.

Several studies are conducted to explain the impact of the electroforming process on the device stability of the epitaxial Fe-doped SrTi[O.sub.3] resistive switching cells. The cells are shown to be extremely stable at moderate temperatures, hence leading to its interaction with the surrounding atmosphere.

Byline: Tee-Yuan Chen, Dau-Chung Wang The goal of this research is to develop a new additive for Ni-Co-Mn ternary alloy electroforming. Under the new recipe, we can control the composition of Ni-Co-Mn, and prove that electroformed ternary Ni-Co-Mn alloy has better mechanical properties than electroformed Ni-Co alloy. This paper also discusses the effect of the Mn concentration on the resulting mechanical properties of electroformed Ni-Co-Mn alloy.

The switching of electroplated Nickel-pillars with diameters smaller 170 nm and heights greater 300 nm was investigated. The nanomagnets were placed on top of the sensor either individually or in groups of 5 up to 13 in different patterns. The individual pillars show two types of hysteresis loops: one type resembles a perfect rectangular hysteresis trace over a wide temperature range, the other type shows two steps in the Hall-voltage when magnetization direction is reversed. The switching field [H.sub.sw] of a pillar with rectangular hysteresis trace was measured between 1.6 K and 225 K. [H.sub.sw] decreases linearly with increasing temperature. Both results as well as the variation of switching fields of different 'single domain' particles suggest, that oxide layers on the surface of the pillars strongly influence the magnetization reversal. Despite this complication small arrays of Ni pillars placed on the sensor display a well defined switching behavior. Different steps in the Hall-voltage reflect the switching of the individual magnets. Index Terms--2DEG, electrodeposition, Hall-sensors, nanomagnet.

High quality nickel films were electrodeposited directly onto n-GaAs using galvanostatic control. It was seen that by varying the current density the crystallographic orientation of the films could be controlled. For a current density of 15 mA/[cm.sup.2], a highly dominant (220) crystallographic orientation was obtained. Magnetic measurements revealed a strong uniaxial anisotropy in these films. Moreover, Kerr spectroscopy measurements (1.4 to 4.5 eV) showed an enhanced Kerr rotation of -0.17 [degrees] at 3.2 eV, which may be attributed to the strong magnetic anisotropy and the exceptional crystal quality of the films. Index Terms--Anisotropy, Electrodeposition, GaAs, Magneto-optical Kerr spectroscopy, Nickel.

Co-Pd alloy films were prepared by electrodeposition. In order to induce composition modulation in the growth direction, a short, high current pulse for Co-rich layer deposition and a long, low current pulse for Pd-rich layer deposition were alternately applied. Perpendicular magnetization films were successfully prepared by adjusting the duration of current pulses. Though the coercivity exceeded 100 kA/m, layered structure was not confirmed. Further studies on the film structure are necessary in order to clarify the origin of the perpendicular anisotropy. Index Terms--Co-Pd alloy film, composition modulation, electrodeposition, perpendicular magnetic anisotropy.

ASTM International, West Conshohocken, Pa., announces a new Standard Specification for Nickel-Cobalt Alloy Coating. The document outlines requirements for corrosion-resistant coatings of electrodeposited nickel-cobalt on metallic substrates and electrodeposited nickel-cobalt [...]

Photo-electroforming is a new manufacturing process for making microelectromechanical systems (MEMS). Photo-electroforming builds parts by an additive process which defines geometry by depositing powder in layers and creating regions of selective conductivity by laser-enhanced electroless plating. The conductive region is then joined by a second plating to form an integral part. The unmetallized portion is removed by selective etching in one step after all layers are defined and joined. Single-layer and two-layer stand-alone parts made of nickel/silicon carbide composites of overall size 75-100 [[micro]meter] and feature size 25 [[micro]meter] were created. Writing speeds of up to 24 cm/s and in-plane resolution of 15 [[micro]meter] were demonstrated. The high laser-induced plating rates were found to be due to elevated substrate temperatures under the laser spot and enhanced mass transfer due to pumping by the hydrogen bubbles resulting from the plating reaction. In the regimes studied, mass transfer defined the rate limit. The in-plane resolution was found to be limited by a combination of laser spot size, thermal conduction in the substrate, and laser divergence due to gas bubbles. Index Terms - Electroforming, electroless plating, laser-enhanced plating, layered fabrication, microelectromechanical systems, solid freeform fabrication.