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Micrometer nickel columns were fabricated by a novel process called microanode guided electroplating (MAGE). In the MAGE process, a microanode of platinum (125 µm in diameter) was controlled to move in either continuous or intermittent mode to guide the progress of Ni-electroplating. The microfabrication was guided from the location of a copper substrate that is initially in contact with the microanode to develop a micrometer column and its appearance was determined by the motion mode (i.e., continuous or intermittent) of the microanode. The intermittent MAGE was superior to the continuous one for fabricating micrometer nickel columns with fine surface morphology and uniform diameter. Different models are proposed and they are simulated by the commercial software ANSYS 8.0 to understand the quantitative distribution in the process of MAGE.

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Micrometer nickel columns were fabricated locally on a copper substrate in a Watts bath by microanode guided electroplating which is commonly known as localized electrochemical deposition (LECD). A microanode of platinum (125 µm in diameter) served to move up intermittently, thus guiding the growth of Ni deposit from the substrate. The separation between the microanode and top of the microcolumn was initially set at 10 µm before setting out the electroplating. The electroplating current and local potential near the local region after the LECD were monitored and examined in this work. Surface and transverse morphology of the microcolumns were examined through a scanning electron microscope. LECD performed at biases less than 3.56 ± 0.01 V led to columns with smooth surfaces and circular internal transverse fully compacted, whereas when performed at biases higher than 3.56 ± 0.01 V it led to columns with a rough surface and distorted circular internal transverse with porosity in the center. The higher the bias, the worse the surface smoothness. The less circular the transverse, the less compactness in the transverse center. A compromise between the estimated supplying rate and the consumption rate of the nickel ions in the local region after the LECD is discussed to understand the dependence of the morphologies on the biases.