A high pH citrate electrolyte was used to electrodeposit Ni-Cu alloys and Ni-Cu-␥-Al 2 O 3 nanocomposites into recessed microelectrodes and onto rotating cylinder electrodes. The patterned, recessed substrates were 500 m deep with a 187 ϫ 187 m cross section, produced by X-ray radiation at the LSU synchrotron facility, Center for Advanced Microstructures and Devices. Copper deposition was diffusion controlled and used as a probe to assess changes in mass transport. Nickel deposition was kinetically controlled by keeping the nickel ions in comparable excess to the concentration of copper ions. In the micropost, the copper deposit concentration increased along the height indicative of a changing boundary layer thickness regardless if the particles were present or absent. The addition of alumina nanoparticles in the electrolyte led to an enhancement of copper concentration in the deposit, and hence an enhancement of its mass-transport rate.Electrodeposited alloys and nanocomposites, in numerous applications, have superior properties over their constituent metals. 1-6 In particular, nanocomposites offer an attractive method to combine properties of alloys and nonreactive nanoparticles. For example, nickel-copper alloys have superior corrosion resistance 7 and alumina incorporation is expected to increase hardness and wear resistance as demonstrated by the elemental Cu-Al 2 O 3 8-13 and Ni-Al 2 O 3 13-18systems. While some studies have focused on the parameters that effect particle incorporation, 9,19-21 few involve the influence of the particle on the metal rate. Webb and Robinson 22 have shown that the nickel deposition rate can be inhibited by the presence of low concentrations of submicrometer alumina particles ͑on the order of 10 g/L͒ in the electrolyte. The same has been noted for copper by Stojak and Talbot, 23 for low alumina electrolyte concentrations, but the opposite effect, an enhancement of the copper rate, was also observed with very high particle loadings ͑exceeding 100 g/L͒. The electrodeposition of alloys and composites is favorable for microelectromechanical systems ͑MEMS͒ and high-aspect-ratio deposition due to its cost effective nature and capability for depositing into recessed substrates. There exist few examples of alloy and composite deposition into recessed geometries. A review of alloy electrodeposits realized in recesses can be found by Ehrfeld et al. 24 Electrodeposition of submicrometer SiC-Ni and Al 2 O 3 -Ni composites into LIGA electrodes has been demonstrated by Yeh et al. 25 and Wang, 26 respectively, into LIGA electrodes. Jakob et al. 27 have codeposited nanometric TiO 2 and Al 2 O 3 into microstructures.In this paper, the electrodeposition of graded Ni-Cu alloys and Ni-Cu-Al 2 O 3 nanocomposites into recessed electrodes made using X-ray lithography is presented; and to the authors' knowledge has not been hitherto reported. Experiments using rotating cylinder electrodes ͑RCEs͒ are used to interpret the compositional changes in the recesses. ExperimentalThe electrolyte used for electr...

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A Fe-Co based amorphous magnetic alloy, called FCA is electroplated onto silicon substrates. The electrodeposition is carried out in customized electroplating equipment specifically developed for the FCA chemistry. A micro-inductor utilizing a magnetic core made of FCA is developed and integrated into a dc-dc converter. This work demonstrates the first commercially viable and available product utilizing electroplated magnetic materials on a wafer level in the power management industry.

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